WO2012060012A1

WO2012060012A1 - Control device of internal combustion engine

Info

Publication number: WO2012060012A1
Application number: PCT/JP2010/069706
Authority: WO
Inventors: 卓伊吹
Original assignee: トヨタ自動車株式会社
Priority date: 2010-11-05
Filing date: 2010-11-05
Publication date: 2012-05-10
Also published as: JP5429401B2; JPWO2012060012A1

Abstract

The present invention is a controlling device for a combustion engine provided with a first controlled object (35D) and a second controlled object (52) respectively controlling a first controlled variable (Pim) and a second controlled variable (Regr). The invention pertains to a control device which sets a targeted first manipulated variable (Mv) and a targeted second manipulated variable (Megr) so that the first controlled variable reaches the targeted value (TPim) and the second controlled variable reaches the targeted value (TRegr). The control device controls the first manipulated variable so that the targeted value is achieved, and controls the second manipulated variable so that the target value is achieved, by entering the targeted first manipulated variable in the first controlled object and the targeted second manipulated variable in the second controlled object. During operation of the internal combustion engine (10), an accumulated value (ΣΔPim) of the deviation of the actual first controlled variable in relation to the target first controlled variable is calculated, and an accumulated value (ΣΔRegr) of the deviation of the actual second controlled variable in relation to the target second controlled variable is also calculated. On the basis of the accumulated values, the targeted first manipulated variable and the targeted second manipulated variable are corrected.

Description

Control device for internal combustion engine

The present invention relates to a control device for an internal combustion engine.

Patent Document 1 describes a control device for an internal combustion engine. An internal combustion engine described in Patent Document 1 includes a supercharger that increases the pressure of gas sucked into a combustion chamber, and an exhaust gas recirculation device (hereinafter referred to as exhaust gas recirculation device) that introduces exhaust gas discharged from the combustion chamber into the exhaust passage. This device is referred to as an “EGR device”. The supercharger has a variable nozzle for controlling the pressure of exhaust gas flowing into the exhaust turbine (hereinafter, this pressure is referred to as “exhaust pressure”). Further, the EGR device has a control valve for controlling the amount of exhaust gas (hereinafter referred to as “EGR gas”) introduced into the intake passage (hereinafter referred to as “EGR control valve”). is doing. The control device described in Patent Document 1 controls the pressure of the gas sucked into the combustion chamber by controlling the opening of the variable nozzle (hereinafter, this pressure is referred to as “supercharging pressure”), and EGR control. The amount of EGR gas (in other words, the so-called EGR rate) is controlled by controlling the opening of the valve.

Incidentally, as described in Patent Document 1, in an internal combustion engine having a supercharger and an EGR device, if the opening of the variable nozzle of the supercharger is changed in order to change the supercharging pressure, EGR Even if the opening degree of the EGR control valve of the apparatus is not changed, the EGR rate changes. On the other hand, when the opening degree of the EGR control valve of the EGR device is changed in order to change the EGR rate, the supercharging pressure changes even if the opening degree of the variable nozzle of the supercharger is not changed.

Therefore, in order to accurately control the EGR rate to the target EGR rate when trying to change the supercharging pressure by the supercharger in order to control the supercharging pressure to the target boost pressure, It is preferable to consider the effect of changes in the supply pressure, and when trying to change the EGR rate by the EGR device in order to control the EGR rate to the target EGR rate, the boost pressure is accurately set to the target boost pressure. In order to control, it is preferable to consider the influence of the change in the EGR rate on the supercharging pressure.

For this reason, the control device described in Patent Document 1 controls the supercharging pressure to the target supercharging pressure while considering the influence of the change in supercharging pressure on the EGR rate and the influence of the change in EGR rate on the supercharging pressure. In addition, the opening of the variable nozzle of the supercharger and the opening of the EGR control valve of the EGR device are controlled so that the EGR rate is controlled to the target EGR rate.

JP 2001-59447 A JP 2005-299424 A

By the way, as described above, when considering the effect of the change in the supercharging pressure on the EGR rate and the effect of the change in the EGR rate on the supercharging pressure, the response of the variable nozzle of the supercharger is also the EGR control valve of the EGR device. These effects are considered on the assumption that the response is also the intended response. Therefore, if the response of the variable nozzle is slower or faster than the intended response, or if the response of the EGR control valve is slower or faster than the intended response, the response of the variable nozzle and the response of the EGR control valve. Even if the influence of the change of the supercharging pressure on the EGR rate and the influence of the change of the EGR rate on the supercharging pressure are considered on the assumption that the response is an expected response, the supercharging pressure is not controlled to the target supercharging pressure Or, at least, the supercharging pressure is not controlled with a predetermined followability to the target supercharging pressure, and the EGR rate is not controlled to the target EGR rate, or at least the EGR rate is predetermined to the target EGR rate. It will not be controlled with the following ability. Alternatively, the supercharging pressure and the EGR rate are not controlled with good balance with respect to the target supercharging pressure and the target EGR rate, respectively.

That is, in order to control the supercharging pressure and the EGR rate that influence each other with a predetermined followability to the target supercharging pressure and the target EGR rate, respectively, the response of the variable nozzle or the response of the EGR control valve is expected. If not, the supercharging pressure and the EGR rate are controlled so as to control the target supercharging pressure and the EGR rate with a predetermined follow-up according to the response of the variable nozzle or the response of the EGR control valve, respectively. Control of supply pressure and EGR rate should be changed.

This is equally true when two controlled variables that affect each other are controlled with a predetermined followability to each target controlled variable. That is, in order to control these two control valve amounts with the target follow-up amount with a predetermined followability, if the response of the control object that controls each control amount is not the intended response, these controls The control of each control amount should be changed so that the control amount is controlled with a predetermined followability according to the response of the target.

Accordingly, an object of the present invention is to control two control amounts that affect each other with a predetermined followability to each target control amount, or to control two control amounts that affect each other in a balanced manner with respect to each target control amount. There is to do.

1st invention of this application is the 1st control object which controls the 1st control amount which is one of the 2 control amounts which mutually affect, and the remaining 1 of the 2 control amounts which mutually affect The present invention relates to a control device for an internal combustion engine including a second control target that controls a second control amount.

The control device of the present invention sets the first control amount to be targeted as the target first control amount and sets the second control amount to be targeted as the target second control amount. Then, an operation amount to be input to the first control target in order to make the first control amount reach the target first control amount and make the second control amount reach the target second control amount is set as the target first operation amount. At the same time, the operation amount to be input to the second control target is set as the target second operation amount. Then, an operation amount corresponding to the target first operation amount is input to the first control object, and an operation amount corresponding to the target second operation amount is input to the second control object, thereby setting the first control amount to the target first control. And the second control amount is controlled to the target second control amount.

Here, in the control device of the present invention, during the operation of the internal combustion engine, the integrated value of the deviation of the actual first control amount with respect to the target first control amount is calculated as the first control amount deviation integrated value and the target second control. The integrated value of the deviation of the actual second control amount with respect to the amount is calculated as the second controlled variable deviation integrated value. Then, the target first operation amount and the target second operation amount are corrected based on the first control amount deviation integrated value and the second control amount deviation integrated value.

According to the present invention, the first control amount can be controlled to the target first control amount with a predetermined followability, and the second control amount can be controlled to the target second control amount with a predetermined followability. Or at least the first control amount and the second control amount can be controlled in a balanced manner with respect to the target first control amount and the target second control amount, respectively.

That is, the first control amount is affected by the second control amount. Therefore, the first control amount deviation integrated value includes not only the continuous shift of the first control amount with respect to the target first control amount (that is, the shift of the response of the first control target to the intended response), but also the target first control amount. The deviation of the second controlled variable with respect to the two controlled variables (that is, the deviation of the response of the second controlled object with respect to the intended response) is also reflected. Similarly, in the second control amount deviation integrated value, not only the continuous shift of the second control amount with respect to the target second control amount (that is, the shift of the response of the second control target to the intended response), but also the target The deviation of the first control amount with respect to the first control amount (that is, the deviation of the response of the first control object with respect to the intended response) is also reflected.

Accordingly, in consideration of the relationship between the first control amount deviation integrated value and the second control amount deviation integrated value, is the response of the first control target slower than the intended response or the expected response? Or grasping whether the response of the second control target is faster than the intended response, and whether the response of the second control target is slower than the intended response, is the intended response, or is faster than the intended response Can do.

According to the present invention, based on the first controlled variable deviation integrated value and the second controlled variable deviation integrated value (that is, considering the first controlled variable deviation integrated value and the second controlled variable deviation integrated value). Also, the target first operation amount and the target second operation amount are corrected. That is, whether the response of the first controlled object is slower than the intended response, is the intended response, or is faster than the intended response, and the response of the second controlled object is the expected response The target first manipulated variable and the target second manipulated variable are corrected according to whether the response is slower than the intended response or faster than the intended response. Therefore, if an operation amount corresponding to the corrected target first operation amount is input to the first control object and an operation amount corresponding to the corrected target second operation amount is input to the second control object, The one control amount is controlled with a predetermined followability to the target first control amount and the second control amount is controlled with a predetermined followability to the target second control amount, or at least the first control amount and the first control amount The two control amounts are controlled in a balanced manner with respect to the target first control amount and the target second control amount, respectively.

Since the first control amount and the second control amount are control amounts that influence each other, is the response of the first control target slower than the intended response based only on the first control amount deviation integrated value? Alternatively, it is impossible to accurately grasp whether the response is an intended response or is faster than the intended response. Therefore, when the target first operation amount is corrected in consideration of only the first control amount deviation integrated value, the correction of the target first operation amount includes a deviation of the response of the first control target with respect to the intended response. It is not reflected accurately, and the deviation of the response of the second control object with respect to the intended response is not reflected at all. For this reason, even if the corrected target first operation amount is input to the first control target, the first control amount is not controlled with a predetermined followability to the target first control amount, and at least the first control amount. And the second control amount are not controlled in a balanced manner with respect to the target first control amount and the target second control amount.

On the other hand, whether the response of the second controlled object is slower than the intended response, the expected response, or faster than the intended response based on only the second controlled variable deviation integrated value. I can't figure it out. Therefore, when the target second operation amount is corrected in consideration of only the second control amount deviation integrated value, the correction of the target second operation amount includes a deviation of the response of the second control target with respect to the intended response. Not only is not accurately reflected, but also the deviation of the response of the first control object with respect to the intended response is not reflected at all, so that the corrected target second operation amount is input to the second control object. However, the second control amount is not controlled with a predetermined followability to the target second control amount, and at least the first control amount and the second control amount are less than the target first control amount and the target second control amount. Are not well balanced.

Further, when the first control amount or the second control amount is a control amount that affects the emission discharged from the internal combustion engine, according to the present invention, it is possible to reduce the emission discharged from the internal combustion engine. can get. That is, when the first control amount affects the emission, generally, the emission is reduced as much as possible on the assumption that the first control amount is controlled with a predetermined followability to the target first control amount. When the structure of the internal combustion engine and the control related to the internal combustion engine are determined and the second control amount affects the emission, it is generally determined that the second control amount is controlled with a predetermined followability to the target second control amount. The structure of the internal combustion engine and the control related to the internal combustion engine are determined so as to reduce emissions as much as possible. In addition, when the first control amount affects the emission, the followability of the first control amount with respect to the target first control amount may be determined so that the emission becomes as small as possible, and the second control amount becomes the emission. In the case of influence, the followability of the second control amount with respect to the target second control amount may be determined so that the emission is reduced as much as possible.

In the present invention, as described above, the first control amount is controlled to the target first control amount with a predetermined followability, and the second control amount is controlled to the target second control amount with the predetermined followability. it can. For these reasons, according to the present invention, the emission discharged from the internal combustion engine can be reduced.

In the second invention of the present application, in the first invention, a first control amount deviation integrated value to be compared with the first control amount deviation integrated value is prepared as a first threshold value, and the second A second controlled variable deviation integrated value to be compared with the controlled variable deviation integrated value is prepared as a second threshold value. When the target first manipulated variable and the target second manipulated variable are corrected based on the first controlled variable deviation integrated value and the second controlled variable deviation integrated value, the first controlled variable deviation integrated value is The second control amount deviation integrated value is compared with the second threshold value while being compared with the first threshold value. Then, based on the comparison result of the first control amount deviation integrated value with respect to the first threshold and the comparison result of the second control amount deviation integrated value with respect to the second threshold, the target first operation amount and the target second operation amount. And are corrected.

According to the present invention, the first control amount can be reliably controlled to the target first control amount with a predetermined followability, and the second control amount can be reliably controlled to the target second control amount with the predetermined followability. The effect that it can control is acquired. That is, in the present invention, the correction result of the target first manipulated variable and the target second manipulated variable is a comparison result of the first control variable deviation integrated value with respect to the first threshold value and a comparison result of the second control variable deviation integrated value with respect to the second threshold value. Is used. Therefore, by appropriately setting the first threshold value and the second threshold value, it is possible to reliably control the first control amount with the target first control amount with a predetermined followability and to set the second control amount to the target second value. The target first operation amount and the target second operation amount can be corrected so that the control amount can be reliably controlled with a predetermined followability.

In the third invention of the present application, in the second invention, a comparison result of the first control amount deviation integrated value with respect to the first threshold value and a comparison result of the second control amount deviation integrated value with respect to the second threshold value. When the target first manipulated variable and the target second manipulated variable are corrected based on the above, the first controlled variable deviation integrated value matches the first threshold value, and the second controlled variable deviation integrated value is 2 so that the ratio of the first controlled variable deviation integrated value and the second controlled variable deviation integrated value matches the ratio of the first threshold value to the second threshold value. The first operation amount and the target second operation amount are corrected.

According to the present invention, the first control amount can be controlled more reliably with a predetermined followability to the target first control amount, and the second control amount can be controlled with a predetermined followability to the target second control amount. The effect that it can control reliably is acquired. In other words, in the present invention, the target first manipulated variable and the target second manipulated variable are corrected, so that the first control variable deviation integrated value matches the first threshold value and the second control variable deviation integrated value is the second. It corresponds to the threshold value, or the ratio between the first control amount deviation integrated value and the second control amount deviation integrated value matches the ratio between the first threshold value and the second threshold value. Therefore, the first threshold value and the second threshold value are controlled by the first control amount with the predetermined followability to the target first control amount, and the second control amount is controlled with the predetermined followability to the target second control amount. By setting the threshold value to be set, the first control amount can be more reliably controlled with the target first control amount with the predetermined followability, and the second control amount can be controlled with the target second control amount with the predetermined followability. Therefore, it can control more reliably.

The fourth invention of the present application is a first control object that controls a first control amount that is one of two control amounts that affect each other, and one of the remaining two control amounts that affect each other. The present invention relates to a control device for an internal combustion engine including a second control target that controls a second control amount.

Then, the control device of the present invention sets the control amount to be targeted as the first control amount as the target first control amount, and sets the control amount to be targeted as the second control amount as the target second control amount. . Then, the operation state of the first control target that should be set to reach the first control amount to the target first control amount and the second control amount to the target second control amount is set as the target first operation state. In addition, the operation state of the second control target to be targeted is set as the target second operation state. Then, the second control is performed such that the operation state of the first control object is controlled so that the operation state of the first control object becomes the target first operation state, and the operation state of the second control object becomes the target second operation state. By controlling the operation state of the target, the first control amount is controlled to the target first control amount and the second control amount is controlled to the target second control amount.

Here, in the control device of the present invention, during the operation of the internal combustion engine, the integrated value of the deviation of the actual first control amount with respect to the target first control amount is calculated as the first control amount deviation integrated value and the target second control. The integrated value of the deviation of the actual second control amount with respect to the amount is calculated as the second controlled variable deviation integrated value. Then, the target first operation state and the target second operation state are corrected based on the first control amount deviation integrated value and the second control amount deviation integrated value.

According to the present invention, the first control amount can be controlled to the target first control amount with a predetermined followability, and the second control amount can be controlled to the target second control amount with a predetermined followability. The effect that it can do, or the effect that at least 1st control amount and 2nd control amount can be controlled with sufficient balance with respect to each target 1st control amount and target 2nd control amount is acquired.

That is, as explained in relation to the effect obtained from the first invention, the response of the first control target is determined by considering the relationship between the first control amount deviation integrated value and the second control amount deviation integrated value. Whether the response is slower than the initial response, is the intended response, or is faster than the intended response, and whether the response of the second controlled object is slower than the intended response or the expected response It is possible to grasp whether it is faster than the intended response.

According to the present invention, based on the first controlled variable deviation integrated value and the second controlled variable deviation integrated value (that is, considering the first controlled variable deviation integrated value and the second controlled variable deviation integrated value). The target first operation state and the target second operation state are corrected. That is, whether the response of the first controlled object is slower than the intended response, is the intended response, or is faster than the intended response, and the response of the second controlled object is the expected response The target first operation state and the target second operation state are corrected depending on whether the response is slower than the intended response, or is faster than the intended response. Therefore, if the operation state of the first control object is controlled to the corrected target first operation state and the operation state of the second control object is controlled to the corrected target second operation state, the first control amount is The target controllable amount is controlled with a predetermined followability and the second control amount is controlled with a target followable control amount with a predetermined followability, or at least the first control amount and the second control amount Are controlled in a balanced manner with respect to the target first control amount and the target second control amount.

Since the first control amount and the second control amount are control amounts that influence each other, is the response of the first control target slower than the intended response based only on the first control amount deviation integrated value? Alternatively, it is impossible to accurately grasp whether the response is an intended response or is faster than the intended response. Therefore, when the target first operation state is corrected in consideration of only the first control amount deviation integrated value, the correction of the target first operation state includes a deviation of the response of the first control target with respect to the intended response. In addition to not being accurately reflected, since the deviation of the response of the second control object with respect to the intended response is not reflected at all, the operation state of the first control object is controlled in the corrected target first operation state. Even if this is done, the first control amount is not controlled with a predetermined followability to the target first control amount, and at least the first control amount and the second control amount are the target first control amount and the target second control amount. Are not controlled in a well-balanced manner.

On the other hand, whether the response of the second controlled object is slower than the intended response, the expected response, or faster than the intended response based on only the second controlled variable deviation integrated value. I can't figure it out. Therefore, when the target second operation state is corrected only in consideration of the second control amount deviation integrated value, the correction of the target second operation state includes a deviation of the response of the second control target with respect to the intended response. In addition to not being reflected accurately, since the deviation of the response of the first control object with respect to the intended response is not reflected at all, the operation state of the second control object is controlled in the corrected target second operation state. Even if the second control amount is not controlled with a predetermined followability to the target second control amount, at least the first control amount and the second control amount are the target first control amount and the target second control amount. Are not controlled in a well-balanced manner.

Further, when the first control amount or the second control amount is a control amount that affects the emission discharged from the internal combustion engine, according to the present invention, the reason described in relation to the effect obtained from the first invention and For the same reason, it is possible to reduce the emission discharged from the internal combustion engine.

In the fifth invention of the present application, in the fourth invention, a first control amount deviation integrated value to be compared with the first control amount deviation integrated value is prepared as a first threshold value, and the second A second controlled variable deviation integrated value to be compared with the controlled variable deviation integrated value is prepared as a second threshold value. When the target first operation state and the target second operation state are corrected based on the first control amount deviation integrated value and the second control amount deviation integrated value, the first control amount deviation integrated value is The second control amount deviation integrated value is compared with the second threshold value while being compared with the first threshold value. Then, based on the comparison result of the first control amount deviation integrated value with respect to the first threshold and the comparison result of the second control amount deviation integrated value with respect to the second threshold, the target first operation state and the target second operation state And are corrected.

According to the present invention, the first control amount can be reliably controlled with a predetermined followability to the target first control amount for the same reason as described in relation to the effect obtained from the second invention. In addition, there is an effect that the second control amount can be reliably controlled to the target second control amount with a predetermined followability.

According to a sixth aspect of the present invention, in the fifth aspect, a comparison result of the first control amount deviation integrated value with respect to the first threshold value and a comparison result of the second control amount deviation integrated value with respect to the second threshold value. When the target first operation state and the target second operation state are corrected based on the above, the first control amount deviation integrated value matches the first threshold value, and the second control amount deviation integrated value is 2 so that the ratio of the first controlled variable deviation integrated value and the second controlled variable deviation integrated value matches the ratio of the first threshold value to the second threshold value. The first operation state and the target second operation state are corrected.

According to the present invention, the supercharging pressure can be more reliably controlled with a predetermined followability to the target supercharging pressure for the same reason as described in relation to the effect obtained from the third invention. There is an effect that the EGR rate can be more reliably controlled to the target EGR rate with a predetermined followability.

In the seventh invention of the present application, in any one of the second, third, fifth, and sixth inventions, the first threshold value and the second threshold value are predetermined responses of the first control target. It is set to a value that is a response and can be taken when the response of the second control target is a predetermined response.

According to the present invention, the first control amount can be controlled more reliably with a predetermined followability to the target first control amount, and the second control amount can be controlled with a predetermined followability to the target second control amount. The effect that it can control reliably is acquired. That is, in the present invention, the first threshold value and the second threshold value are set to values that can be taken when the response of the first control target is a predetermined response and the response of the second control target is a predetermined response. . Here, since the first control amount and the second control amount are control amounts that influence each other, the first control amount is controlled to the target first control amount and the second control amount is set to the target second control amount. The control system for controlling is constructed on the assumption that the response of the first control target is a predetermined response and the response of the second control target is a predetermined response. For this reason, the first threshold value and the second threshold value are set to values that can be taken when the response of the first control target is a predetermined response and the response of the second control target is a predetermined response. Based on the comparison result between the first threshold value and the first control amount deviation threshold value and the comparison result between the second threshold value and the second control amount deviation threshold value thus set, the target first operation amount and the target second operation If the amount or the target first operation state and the target second operation state are corrected, the first control object is operated so that the response of the first control object becomes a predetermined response, and the response of the second control object is predetermined. Thus, the second control object is operated so as to be a response to the above. Therefore, the first control amount can be more reliably controlled with a predetermined followability to the target first control amount, and the second control amount can be more reliably controlled with a predetermined followability to the target second control amount. It can be done.

1 is a schematic view of an internal combustion engine to which a control device of the present invention is applied. It is the figure which showed the inside of the exhaust turbine of the supercharger of the internal combustion engine shown by FIG. (A) is the figure which showed the map utilized in order to determine a target supercharging pressure, (B) is the figure which showed the map utilized in order to determine a target EGR rate. It is the figure which showed an example of the routine which performs the setting of the target vane operation amount and target EGR control valve operation amount according to 1st Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to 1st Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to 1st Embodiment of this invention. It is the figure which showed an example of the routine which performs the setting of the target vane manipulated variable and the target EGR control valve manipulated variable according to 2nd Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane opening proportional gain and EGR control valve opening proportional gain according to 2nd Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane opening proportional gain and EGR control valve opening proportional gain according to 2nd Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to 4th Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to 4th Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to 4th Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to 4th Embodiment of this invention. It is the figure which showed an example of the routine which performs the setting of the target vane manipulated variable, the target EGR control valve manipulated variable, and the target throttle valve manipulated variable according to 5th Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the supercharging pressure weight gain and EGR rate weight gain according to 5th Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the supercharging pressure weight gain and EGR rate weight gain according to 5th Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to 6th Embodiment of this invention. It is the figure which showed a part of example of the routine which performs correction | amendment of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to 6th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an internal combustion engine 10 to which the control device of the present invention is applied. The internal combustion engine 10 includes an internal combustion engine main body (hereinafter referred to as “engine main body”) 20, fuel injection valves 21 disposed corresponding to the four combustion chambers of the engine main body, and fuel supply to the fuel injection valves 21. And a fuel pump 22 for supplying fuel via a pipe 23. The internal combustion engine 10 further includes an intake system 30 that supplies air to the combustion chamber from the outside, and an exhaust system 40 that exhausts exhaust gas discharged from the combustion chamber to the outside. The internal combustion engine 10 is a compression self-ignition internal combustion engine (so-called diesel engine).

The intake system 30 includes an intake branch pipe 31 and an intake pipe 32. In the following description, the intake system 30 may be referred to as an “intake passage”. One end portion (that is, a branch portion) of the intake branch pipe 31 is connected to an intake port (not shown) formed in the engine body 20 corresponding to each combustion chamber. On the other hand, the other end of the intake branch pipe 31 is connected to the intake pipe 32. A throttle valve 33 that controls the amount of air flowing through the intake pipe is disposed in the intake pipe 32. Further, an intercooler 34 for cooling the air flowing through the intake pipe is disposed in the intake pipe 32. Further, an air cleaner 36 is disposed at an end facing the outside of the intake pipe 32.

The throttle valve 33 controls the operating state (specifically, its opening, which will be referred to as “throttle valve opening” hereinafter). The amount can be controlled variably.

On the other hand, the exhaust system 40 includes an exhaust branch pipe 41 and an exhaust pipe 42. In the following description, the exhaust system 40 may be referred to as an “exhaust passage”. One end portion (that is, a branch portion) of the exhaust branch pipe 41 is connected to an exhaust port (not shown) formed in the engine body 20 corresponding to each combustion chamber. On the other hand, the other end of the exhaust branch pipe 41 is connected to the exhaust pipe 42. In the exhaust pipe 42, a catalytic converter 43 having an exhaust purification catalyst 43A for purifying a specific component in the exhaust gas is disposed.

Further, the internal combustion engine 10 includes a supercharger 35. The supercharger 35 includes a compressor 35A disposed in the intake pipe 32 upstream of the intercooler 34, and an exhaust turbine 35B disposed in the exhaust pipe 42 upstream of the catalytic converter 43. As shown in FIG. 2, the exhaust turbine 35B includes an exhaust turbine main body 35C and a plurality of blade-like vanes 35D.

The exhaust turbine 35B (strictly, the exhaust turbine main body 35C) is connected to the compressor 35A via a shaft (not shown). When the exhaust turbine main body 35C is rotated by the exhaust gas, the rotation is transmitted to the compressor 35A via the shaft, whereby the compressor 35A is rotated. The rotation of the compressor 35A compresses the gas in the intake pipe 32 downstream of the compressor, and as a result, the pressure of the gas (hereinafter, this pressure is referred to as “supercharging pressure”) is increased.

On the other hand, the vanes 35D are radially arranged at equiangular intervals around the rotation center axis R1 of the exhaust turbine body so as to surround the exhaust turbine body 35C. Each vane 35D is disposed so as to be rotatable around a corresponding axis indicated by reference numeral R2 in FIG. The direction in which each vane 35D extends (ie, the direction indicated by symbol E in FIG. 2) is referred to as the “extending direction”, and the rotation center axis R1 of the exhaust turbine main body 35C and the rotation of the vane 35D. When a line connecting to the movement axis R2 (that is, a line indicated by a symbol A in FIG. 2) is referred to as a “reference line”, each vane 35D has an extending direction E and a corresponding reference line A. Is rotated so that the angles formed by the two are equal for all the vanes 35D. When each vane 35D is rotated so that the angle formed by the extending direction E and the corresponding reference line A is small, that is, the flow area between the adjacent vanes 35D is small, The pressure in the exhaust passage 40 upstream of the exhaust turbine body 35C (hereinafter, this pressure is referred to as “exhaust pressure”) increases, and as a result, the flow rate of the exhaust gas supplied to the exhaust turbine body 35C increases. For this reason, the rotational speed of the exhaust turbine body 35C is increased, and as a result, the rotational speed of the compressor 35A is also increased. Therefore, the gas flowing in the intake pipe 32 is greatly compressed by the compressor 35A. For this reason, the gas flowing through the intake pipe 32 is compressed by the compressor 35A as the angle formed between the extending direction E of each vane 35D and the corresponding reference line (hereinafter, this angle is referred to as “vane opening degree”) becomes smaller. (That is, the supercharging pressure increases).

Therefore, the supercharger 35 can variably control the supercharging pressure by controlling the operating state (specifically, the vane opening degree) of the vane 35D.

In addition, the internal combustion engine 10 includes an exhaust gas recirculation device (hereinafter referred to as “EGR device”) 50. The EGR device 50 includes an exhaust gas recirculation pipe (hereinafter referred to as “EGR passage”) 51. One end of the EGR passage 51 is connected to the exhaust branch pipe 41. That is, one end of the EGR passage 51 is connected to a portion of the exhaust passage 40 upstream of the exhaust turbine 35B. On the other hand, the other end of the EGR passage 51 is connected to the intake branch pipe 31. That is, the other end of the EGR passage 51 is connected to a portion of the intake passage downstream of the compressor 35A. Further, an exhaust gas recirculation control valve (hereinafter, this exhaust gas recirculation control valve is referred to as an “EGR control valve”) 52 that controls the flow rate of exhaust gas flowing through the EGR passage is disposed in the EGR passage 51. In the internal combustion engine 10, the flow rate of the exhaust gas flowing through the EGR passage 51 increases as the opening degree of the EGR control valve 52 (hereinafter, this opening degree is referred to as “EGR control valve opening degree”). Further, an exhaust gas recirculation cooler 53 for cooling the exhaust gas flowing in the EGR passage is disposed in the EGR passage 51.

The EGR device 50 controls the operating state of the EGR control valve 52 (specifically, the opening degree of the EGR control valve 52, which is hereinafter referred to as “EGR control valve opening degree”). The amount of exhaust gas introduced into the intake passage 30 via the EGR passage 51 (hereinafter, this exhaust gas is referred to as “EGR gas”) can be variably controlled.

Further, an air flow meter 71 for detecting the flow rate of the air flowing in the intake pipe is attached to the intake pipe 32 downstream of the air cleaner 36 and upstream of the compressor 35A. Further, a pressure sensor (hereinafter referred to as “supercharging pressure sensor”) 72 for detecting the pressure of the gas in the intake branch pipe (that is, the supercharging pressure) is attached to the intake branch pipe 31. The engine body 20 is provided with a crank position sensor 74 for detecting the rotational phase of the crankshaft.

In addition, the internal combustion engine 10 includes an electronic control device 60. The electronic control device 60 includes a microprocessor (CPU) 61, a read only memory (ROM) 62, a random access memory (RAM) 63, a backup RAM (Back up RAM) 64, and an interface 65. The fuel injection valve 21, the fuel pump 22, the throttle valve 33, the vane 35 </ b> D, and the EGR control valve 52 are connected to the interface 65, and control signals for controlling these operations are transmitted via the interface 65 to the electronic control device. 60. The interface 65 includes an air flow meter 71, a supercharging pressure sensor 72, a crank position sensor 74, and an opening degree of the accelerator pedal AP (that is, an amount of depression of the accelerator pedal AP. An accelerator pedal opening sensor 75 for detecting the degree of pressure) is also connected, a signal corresponding to the flow rate detected by the air flow meter 71, a signal corresponding to the pressure detected by the supercharging pressure sensor 72, a crank position sensor A signal corresponding to the rotational phase of the crankshaft detected by 74 and a signal corresponding to the depression amount of the accelerator pedal AP detected by the accelerator pedal opening sensor 75 are input to the interface 65.

The supercharging pressure is calculated by the electronic control unit 60 based on the signal corresponding to the pressure detected by the supercharging pressure sensor 72 and is based on the signal corresponding to the rotational phase of the crankshaft detected by the crank position sensor 74. Then, the engine speed (that is, the speed of the internal combustion engine 10) is calculated by the electronic control unit 60, and the accelerator pedal opening degree is based on a signal corresponding to the depression amount of the accelerator pedal AP detected by the accelerator pedal opening degree sensor 75. Is calculated by the electronic control unit 60.

By the way, in the present embodiment (hereinafter referred to as “first embodiment”), an actual boost pressure is set to a target value of boost pressure (hereinafter referred to as “target boost pressure”) set as described later. (Hereinafter, this supercharging pressure is also referred to as “actual supercharging pressure”). Further, when the ratio of the amount of EGR gas contained in the gas to the amount of gas sucked into the combustion chamber is referred to as “EGR rate”, in the first embodiment, the EGR rate set as described later is set. The actual EGR rate (hereinafter, this EGR rate is also referred to as “actual EGR rate”) is controlled to the target value (hereinafter, this target value is referred to as “target EGR rate”).

Next, setting of the target boost pressure and the target EGR rate according to the first embodiment will be described. In the following description, the “engine operating state” is “the operating state of the internal combustion engine 10”, the “engine load” is “the load of the internal combustion engine 10”, and the “engine speed” is “the engine rotational speed”. “Rotational speed”, and “During engine operation” is “During operation of internal combustion engine 10”.

In the first embodiment, when an engine operating state in which the change amount of the engine speed per unit time is substantially zero and the change amount of the engine load per unit time is substantially zero is referred to as a steady operation state, The supercharging pressure that should be the target when the operating state is in the steady operating state is obtained in advance by experiments or the like, and these supercharging pressures are used as the target supercharging pressure TPim as shown in FIG. It is stored in the electronic control unit 60 in the form of a function map of the number N and the engine load L (hereinafter, this map is also referred to as “target boost pressure map”). During engine operation, the target boost pressure TPim is acquired from the boost pressure map based on the engine speed N and the engine load L, and the acquired target boost pressure TPim is set as the target boost pressure. The

Further, the oxygen concentration in the intake gas to be targeted when the engine operation state is in the steady operation state is obtained in advance by experiments or the like, and these oxygen concentrations are the target oxygen concentration as shown in FIG. It is stored in the electronic control unit 60 in the form of a function map of the engine speed N and the engine load L (hereinafter, this map is also referred to as “target oxygen concentration map”) as TO2. During engine operation, the target oxygen concentration TO2 is acquired from the target oxygen concentration map based on the engine speed N and the engine load L, and the acquired target oxygen concentration TO2 is set as the target oxygen concentration.

When the actual boost pressure is controlled to the target boost pressure TPim, the actual oxygen concentration in the intake gas (hereinafter, this oxygen concentration is also referred to as “actual oxygen concentration”) is set to the target oxygen concentration TO2. A possible EGR rate is calculated as the target EGR rate. In other words, the target EGR rate is calculated based on the actual supercharging pressure and the target oxygen concentration TO2.

By the way, in the first embodiment, the operation amount to be input to the vane 35D in order to set the actual supercharging pressure to the target supercharging pressure is calculated (ie, set) as the target vane operation amount, and this calculated target An operation amount corresponding to the vane operation amount is input to the vane 35D. As a result, the actual boost pressure is controlled to the target boost pressure.

In the first embodiment, the operation amount to be input to the EGR control valve 52 in order to set the actual EGR rate to the target EGR rate is calculated (that is, set) as the target EGR control valve operation amount. The operation amount corresponding to the target EGR control valve operation amount is input to the EGR control valve 52. As a result, the actual EGR rate is controlled to the target EGR rate.

Next, setting of the target vane operation amount according to the first embodiment will be described. In the first embodiment, so-called PID control (that is, proportional-integral-derivative control) that is feedback control based on the deviation of the actual supercharging pressure with respect to the target supercharging pressure is used for setting the target vane operation amount. Specifically, the actual boost pressure is acquired during engine operation, and the deviation of the acquired actual boost pressure with respect to the target boost pressure is calculated as the boost pressure deviation. Then, the supercharging pressure deviation integrated value is calculated by integrating the supercharging pressure deviation thus calculated.

The supercharging pressure deviation calculated as described above is represented by “ΔPim”, the supercharging pressure deviation integrated value calculated as described above is represented by “ΣΔPim”, and the target vane operation amount is represented by “Mv”. The so-called proportional gain is represented by “GPp”, the so-called integral gain is represented by “GPi”, the so-called differential gain is represented by “GPd”, and the so-called reference vane operation amount is represented by “Mvbse”. A vane operation amount Mv is calculated. The reference vane operation amount is a vane operation amount when the engine operating state is in a steady operation state, and is obtained in advance through experiments or the like, and is an electronic control device in the form of a map of a function of the engine speed N and the engine load L. 60.
Mv = GPp × ΔPim + GPi × ΣΔPim + GPd × d (ΔPim) / dt + Mvbse (1)

In the first embodiment, the target vane operation amount Mv calculated from Equation 1 is set as the target vane operation amount, and the operation amount corresponding to the set target vane operation amount is transferred from the electronic control device 60 to the vane 35D. Is input.

Next, the setting of the target EGR control valve operation amount according to the first embodiment will be described. In the first embodiment, so-called PID control, which is feedback control based on the deviation of the actual EGR rate with respect to the target EGR rate, is used for setting the target EGR control valve operation amount. Specifically, the actual EGR rate is acquired during engine operation, and the deviation of the acquired actual EGR rate with respect to the target EGR rate is calculated as the EGR rate deviation. Then, the EGR rate deviation integrated value is calculated by integrating the EGR rate deviation thus calculated.

Then, the EGR rate deviation calculated as described above is represented by “ΔRegr”, the EGR rate deviation integrated value calculated as described above is represented by “ΣΔRegr”, the target EGR control valve operation amount is represented by “Megr”, When a so-called proportional gain is represented by “GEp”, a so-called integral gain is represented by “GEi”, a so-called differential gain is represented by “GPd”, and a so-called reference EGR control valve operation amount is represented by “Megrbse”, A target EGR control valve operation amount Megr is calculated. The reference EGR control valve operation amount is an EGR control valve operation amount when the engine operation state is in a steady operation state, and is obtained in advance by an experiment or the like and forms a function map of the engine speed N and the engine load L. Is stored in the electronic control unit 60.
Megr = GEp × ΔRegr + GEi × ΣΔRegr + GEd × d (ΔRegr) / dt + Megrbse (2)

In the first embodiment, the target EGR control valve operation amount Megr calculated from Equation 2 is set as the target EGR control valve operation amount, and the operation amount corresponding to the set target EGR control valve operation amount is an electronic value. It is input from the control device 60 to the EGR control valve 52.

By the way, in the first embodiment, in order to control the actual supercharging pressure to the target supercharging pressure with a predetermined followability and to control the actual EGR rate to the target EGR rate with a predetermined followability, the target vane operation amount The proportional gain of the above equation 1 (hereinafter referred to as “vane operation amount proportional gain”) and the proportional gain of the above equation 2 (hereinafter referred to as this gain) used to set the target EGR control valve operation amount. "EGR control valve operation amount proportional gain") is corrected based on the supercharging pressure deviation integrated value and the EGR rate deviation integrated value, and the corrected vane operation amount proportional gain is used as the proportional gain of Equation 1 above. Thus, the target vane operation amount is set, and the corrected EGR control valve operation amount proportional gain is used as the proportional gain of the above equation 2 to set the target EGR control valve operation amount. In other words, in the first embodiment, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are learned based on the boost pressure deviation integrated value and the EGR rate deviation integrated value, and these are learned. The vane operation amount proportional gain and the EGR control valve operation amount proportional gain are used for setting the target vane operation amount and setting the target EGR control valve operation amount.

Next, correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain will be described.

In the first embodiment, the supercharging pressure deviation integrated value calculated during engine operation is compared with a reference value (hereinafter, this value is referred to as “reference value”) and is calculated during engine operation. The EGR rate deviation integrated value is compared with a reference value (hereinafter referred to as “reference value”).

Here, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, a predetermined value (hereinafter referred to as this value) is set so that the vane operation amount proportional gain is increased. (The first correction value) is added to the vane operation amount proportional gain so that the gain is corrected and the EGR control valve operation amount becomes smaller so that the EGR control valve operation amount proportional gain becomes smaller. By subtracting from the proportional gain, the gain is corrected.

Further, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, a predetermined value larger than 1 is set so that the EGR control valve operation amount proportional gain becomes large. By multiplying the value (hereinafter referred to as “second correction value”) by the EGR control valve operation amount proportional gain, the second correction value is adjusted so that the gain is corrected and the vane operation amount proportional gain is increased. The gain is corrected by multiplying the vane operation amount proportional gain.

Further, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to (or equal to) the reference value, the vane operation amount proportional gain is increased. The gain is corrected by multiplying the vane manipulated variable proportional gain by a predetermined value greater than 1 (hereinafter referred to as “third correction value”) and the EGR control valve manipulated variable proportional gain is increased. In this way, the third correction value is multiplied by the EGR control valve operation amount proportional gain to correct the gain.

In addition, when the relationship between the supercharging pressure deviation integrated value with respect to the reference value and the relationship between the EGR rate deviation integrated value with respect to the reference value is other than the above-mentioned relationship, the vane operation amount proportional gain is also proportional to the EGR control valve operation amount proportional. Gain is not corrected.

In the first embodiment, for example, the supercharging pressure deviation integrated value and the EGR rate deviation integrated value that can be taken when the response of the vane is the highest and the response of the EGR control valve is the highest are obtained in advance through experiments or the like. These values are used as a reference value for the supercharging pressure deviation integrated value and a reference value for the EGR rate deviation integrated value, respectively.

As described above, when the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected, and these corrected gains are used for setting the target vane operation amount and the target EGR control valve operation amount, respectively, The effect that the supply pressure can be controlled to the target supercharging pressure with predetermined followability and the EGR rate can be controlled to the target EGR rate with predetermined followability, or the supercharging pressure and the EGR rate Can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate.

That is, the EGR device 50 can variably control the amount of EGR gas by controlling the EGR control valve opening. That is, the EGR device 50 can variably control the actual EGR rate by controlling the EGR control valve opening. Here, if the EGR control valve opening is increased in order to increase the EGR rate, the amount of EGR gas increases. Therefore, the exhaust pressure 40 (ie, the exhaust passage 40 upstream of the exhaust turbine 35B of the supercharger 35). The pressure of the exhaust gas in the inside is reduced. For this reason, the compression effect of the supercharger 35 on the gas flowing in the intake pipe 32 is reduced, and as a result, the supercharging pressure is reduced. On the other hand, if the EGR control valve opening is reduced in order to reduce the EGR rate, the amount of EGR gas decreases, so that the exhaust pressure increases. For this reason, the compression effect of the supercharger 35 with respect to the gas flowing through the intake pipe 32 increases, and as a result, the supercharging pressure increases. That is, the control of the EGR gas amount by the EGR device 50 (as a result, the control of the EGR rate by the EGR device 50) affects the supercharging pressure.

Therefore, when the supercharger 35 tries to control the supercharging pressure with a predetermined followability to the target supercharging pressure, the influence of the supercharging pressure control by the supercharger 35 on the supercharging pressure. It is advantageous to consider the influence of the control of the EGR rate by the EGR device 50 on the supercharging pressure as well.

On the other hand, the supercharger 35 can variably control the supercharging pressure by controlling the vane opening. Here, if the vane opening is made small in order to increase the supercharging pressure, the exhaust pressure increases, so the differential pressure between the supercharging pressure and the exhaust pressure increases, and as a result, the amount of EGR gas increases. . On the other hand, if the vane opening is increased in order to reduce the supercharging pressure, the exhaust pressure decreases, so that the differential pressure between the supercharging pressure and the exhaust pressure decreases, and as a result, the EGR gas amount decreases. That is, the control of the supercharging pressure by the supercharger 35 affects the EGR gas amount (as a result, the EGR rate).

Therefore, when the EGR device 50 tries to control the EGR rate to the target EGR rate with a predetermined followability, not only the influence of the control of the EGR rate by the EGR device 50 on the EGR rate but also the excess on the EGR rate is considered. It is advantageous to consider the influence of supercharging pressure control by the feeder 35.

Thus, the supercharging pressure and the EGR rate are control amounts that influence each other. Therefore, when trying to control the supercharging pressure to the target supercharging pressure with a predetermined followability by the supercharger 35, only the influence of the control of the supercharging pressure by the supercharger 35 on the supercharging pressure is considered. In addition, considering the influence of the control of the EGR rate by the EGR device 50 on the supercharging pressure is advantageous from the viewpoint of controlling the supercharging pressure to the target supercharging pressure with higher accuracy. Further, when the EGR device 50 tries to control the EGR rate with a predetermined followability to the target EGR rate, not only the influence of the control of the EGR rate by the EGR device 50 on the EGR rate but also the EGR rate is not considered. Considering the influence of supercharging pressure control by the supercharger 35 is advantageous from the viewpoint of controlling the EGR rate to the target EGR rate with higher accuracy.

Here, in general, the proportional gain, integral gain, and differential gain of the above equation 1 are set so that the supercharging pressure becomes the target excess when the target vane operation amount Mv calculated from the above equation 1 is input to the vane. A target vane operation amount that is appropriately controlled with predetermined followability to the supply pressure is obtained in advance by experiments or the like as a value calculated from the above equation 1. In this regard, as described above, since the supercharging pressure is affected by the EGR rate, a proportional gain, an integral gain, and a derivative gain (hereinafter referred to as “reference proportional gain”, “ It can be said that the “reference integral gain” and the “reference differential gain” are values based on the premise that the EGR rate is appropriately controlled with a predetermined followability to the target EGR rate. Therefore, the target vane operation amount calculated from the above equation 1 that employs the reference proportional gain, the reference integral gain, and the reference differential gain is controlled with a predetermined followability of the supercharging pressure to the target supercharging pressure. It is set on the assumption that the EGR rate is controlled with a predetermined followability to the target EGR rate. Therefore, when the target vane operation amount calculated from the above equation 1 that employs the reference proportional gain, the reference integral gain, and the reference differential gain is input to the vane, the supercharging pressure has a predetermined followability to the target supercharging pressure. Therefore, as long as it is controlled and the EGR rate is controlled with a predetermined followability to the target EGR rate, the supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

In other words, when the supercharging pressure is not controlled with a predetermined followability to the target supercharging pressure, the target vane calculated from the above equation 1 that employs the reference proportional gain, the reference integral gain, and the reference differential gain. Even if the operation amount is input to the vane, it is natural that the supercharging pressure is not controlled with a predetermined followability to the target supercharging pressure. Further, even when the EGR rate is not controlled with a predetermined followability to the target EGR rate, the target vane operation amount calculated from the above equation 1 that employs the reference proportional gain, the reference integral gain, and the reference differential gain is the vane. Even if it is input to the supercharging pressure, the supercharging pressure is not controlled with a predetermined followability to the target supercharging pressure.

Similarly, generally, the proportional gain, integral gain, and differential gain of the above equation 2 are the EGR rate when the target EGR control valve operation amount Megr calculated from the above equation 4 is input to the EGR control valve. The target EGR control valve operation amount that is appropriately controlled with a predetermined followability to the target EGR rate is obtained in advance by experiments or the like as a value calculated from the above equation 2. In this regard, since the EGR rate is affected by the supercharging pressure as described above, the proportional gain, integral gain, and derivative gain (hereinafter referred to as “reference proportional gain”, “ It can also be said that the “reference integral gain” and “reference differential gain” are values based on the premise that the supercharging pressure is appropriately controlled with a predetermined followability to the target supercharging pressure. Therefore, the target EGR control valve operation amount calculated from the above equation 2 that employs the reference proportional gain, the reference integral gain, and the reference differential gain is controlled with a predetermined followability of the EGR rate to the target EGR rate. At the same time, the supercharging pressure is set on the premise that the supercharging pressure is controlled with a predetermined followability to the target supercharging pressure. Therefore, when the target EGR control valve operation amount calculated from the above equation 2 that employs the reference proportional gain, the reference integral gain, and the reference differential gain is input to the EGR control valve, the EGR rate is set to the target EGR rate. As long as it is controlled with follow-up and the supercharging pressure is controlled with a predetermined follow-up to the target supercharging pressure, the EGR rate is controlled with a predetermined follow-up with respect to the target EGR rate.

In other words, when the EGR rate is not controlled with a predetermined followability to the target EGR rate, the target EGR control valve calculated from the above equation 2 adopting the reference proportional gain, the reference integral gain, and the reference differential gain. Even if the operation amount is input to the EGR control valve, as a matter of course, the EGR rate is not controlled with a predetermined followability to the target EGR rate. Further, even when the supercharging pressure is not controlled with a predetermined followability to the target supercharging pressure, the target EGR control valve calculated from the above equation 2 that employs the reference proportional gain, the reference integral gain, and the reference differential gain. Even if the operation amount is input to the EGR control valve, the EGR rate is not controlled with a predetermined followability to the target EGR rate.

If the supercharging pressure is not controlled with the target supercharging pressure with a predetermined followability, or the EGR rate is not controlled with the target EGR rate with a predetermined followability, the supercharging pressure follows the target supercharging pressure with a predetermined followability. Therefore, if the EGR rate is controlled with the predetermined EGR rate and the target EGR rate is controlled with a predetermined followability, the desired internal combustion engine characteristics cannot be obtained.

Here, if the response of the vane is slower than the intended response although the response of the EGR control valve is the intended response, the boost pressure deviation integrated value is larger than the reference value and the EGR The rate deviation integrated value becomes smaller than the reference value. Next, this will be described.

That is, when the target supercharging pressure is increased, the target EGR rate is decreased. Therefore, at this time, the vane opening is made small in order to increase the actual supercharging pressure toward the target supercharging pressure, and at the same time, the EGR control valve opening is used to decrease the actual EGR rate toward the target EGR rate. Is reduced.

Here, as described above, when the vane opening is decreased, the exhaust pressure increases, and as a result, the supercharging pressure increases. On the other hand, even if the EGR control valve opening is reduced, the exhaust pressure increases, and as a result, the supercharging pressure increases. That is, when the vane opening and the EGR control valve opening are simultaneously reduced, the supercharging is caused by the increase in the exhaust pressure due to the decrease in the vane opening and the increase in the exhaust pressure due to the decrease in the EGR control valve opening. The pressure will be raised. Here, when the response of the vane is slower than the intended response even though the response of the EGR control valve is the intended response, the rate of increase of the exhaust pressure due to the decrease in the opening degree of the EGR control valve is In spite of this speed, the exhaust pressure increase rate due to the decrease in the vane opening becomes slower than the intended speed. For this reason, as a whole, the increase speed of the supercharging pressure becomes slower than the intended speed. Therefore, when the actual supercharging pressure is to be increased when the response of the EGR control valve is the intended response but the vane response is slower than the intended response, the supercharging pressure deviation integrated value is It becomes larger than the reference value.

On the other hand, as described above, when the vane opening is reduced, the exhaust pressure increases, and as a result, the differential pressure between the exhaust pressure and the supercharging pressure increases, and the EGR gas amount increases. On the other hand, when the EGR control valve opening is reduced, the EGR gas amount naturally decreases. That is, when the vane opening and the EGR control valve opening are simultaneously reduced, an increase in the EGR gas amount due to the decrease in the vane opening and a decrease in the EGR gas amount due to the decrease in the EGR control valve opening. It occurs at the same time. Here, when the response of the vane is slower than the intended response even though the response of the EGR control valve is the intended response, the rate of decrease of the EGR gas amount due to the decrease in the opening degree of the EGR control valve is The increase rate of the EGR gas amount due to the decrease in the vane opening degree is slower than the intended speed, regardless of the intended speed. For this reason, as a whole, the rate of decrease of the EGR gas amount becomes faster than the intended rate. Therefore, when the actual EGR rate is to be reduced when the response of the vane is slower than the intended response even though the response of the EGR control valve is the intended response, the integrated value of the EGR rate deviation is the reference value. Smaller than the value.

Also, when the target supercharging pressure is lowered, the target EGR rate is raised. Accordingly, at this time, the vane opening is increased in order to decrease the actual supercharging pressure toward the target supercharging pressure, and at the same time, the EGR control valve opening is increased in order to increase the actual EGR rate toward the target EGR rate. Is also enlarged.

Here, as described above, when the vane opening degree is increased, the exhaust pressure is decreased, and as a result, the supercharging pressure is decreased. On the other hand, even if the EGR control valve opening is increased, the exhaust pressure decreases, and as a result, the supercharging pressure decreases. That is, when the vane opening and the EGR control valve opening are simultaneously increased, supercharging is caused by a decrease in the exhaust pressure due to the increase in the vane opening and a decrease in the exhaust pressure due to the increase in the EGR control valve opening. The pressure will be reduced. Here, when the response of the vane is slower than the intended response although the response of the EGR control valve is the intended response, the rate of decrease in the exhaust pressure due to the increase in the opening degree of the EGR control valve is In spite of this speed, the exhaust pressure lowering speed due to the increase in the vane opening becomes slower than the intended speed. For this reason, as a whole, the decrease speed of the supercharging pressure becomes slower than the intended speed. Therefore, when the actual boost pressure is to be reduced when the response of the EGR control valve is the intended response but the vane response is slower than the intended response, the boost pressure deviation integrated value is It becomes larger than the reference value.

On the other hand, as described above, when the vane opening degree is increased, the exhaust pressure is decreased, and as a result, the differential pressure between the exhaust pressure and the supercharging pressure is decreased, so that the EGR gas amount is decreased. On the other hand, when the EGR control valve opening is increased, the amount of EGR gas naturally increases. That is, when the vane opening and the EGR control valve opening are increased simultaneously, the decrease in the EGR gas amount due to the increase in the vane opening and the increase in the EGR gas amount due to the increase in the EGR control valve opening. It occurs at the same time. Here, when the response of the vane is slower than the intended response although the response of the EGR control valve is the intended response, the increase rate of the EGR gas amount due to the increase of the EGR control valve opening degree is Despite the initial speed, the rate of decrease in the EGR gas amount due to the increase in the vane opening becomes slower than the intended speed. For this reason, as a whole, the increasing rate of the EGR gas amount becomes faster than the intended rate. Accordingly, when the actual EGR rate is to be increased when the response of the vane is slower than the intended response even though the response of the EGR control valve is the intended response, the EGR rate deviation integrated value is the reference value. Smaller than the value.

Thus, when the response of the EGR control valve is the intended response but the vane response is slower than the intended response, the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation The integrated value becomes smaller than the reference value.

Here, if the amount of vane operation is increased, the response of the vanes becomes faster. Therefore, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, if the vane operation amount is increased, the response of the vane becomes faster. The actual turbocharging pressure change speed (that is, the actual turbocharging pressure increasing speed when increasing the actual turbocharging pressure, or the actual turbocharging pressure decreasing speed when decreasing the actual turbocharging pressure) It will approach speed. Therefore, in the first embodiment, in this case, the first correction value is added to the vane operation amount proportional gain so as to increase the vane operation amount proportional gain. Thus, if the vane operation amount proportional gain is increased, the set target vane operation amount is increased. According to this, the response of the vane becomes faster, and as a result, the change speed of the actual supercharging pressure becomes faster and approaches the intended speed. Then, if the correction of the vane operation amount proportional gain is repeated, the change speed of the actual supercharging pressure finally reaches the intended speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

On the other hand, if the operation amount of the EGR control valve is reduced, the response of the EGR control valve is delayed. Therefore, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, if the EGR control valve operation amount is reduced, the response of the EGR control valve is delayed. As a result, the change rate of the actual EGR rate (that is, the decrease rate of the actual EGR rate when the actual EGR rate is decreased or the increase rate of the actual EGR rate when the actual EGR rate is increased) is an intended rate. Will approach. Therefore, in the first embodiment, in this case, the first correction value is subtracted from the EGR control valve operation amount proportional gain so that the EGR control valve operation amount proportional gain becomes smaller. Thus, if the EGR control valve operation amount proportional gain is decreased, the set target EGR control valve operation amount is decreased. According to this, the response of the EGR control valve becomes slow, and as a result, the change speed of the actual EGR rate becomes slow and approaches the intended speed. Then, if the correction of the EGR control valve operation amount proportional gain is repeated, the actual EGR rate change speed finally reaches the intended speed. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

In addition, according to the correction | amendment of the vane operation amount proportional gain using the 1st correction value mentioned above, since the response of a vane becomes quick, the speed of the change of the EGR gas amount resulting from the change of a vane opening degree becomes quick. Also from this, the rate of change of the actual EGR rate becomes slow and approaches the intended rate. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate earlier.

Thus, according to the first embodiment, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, and therefore the response of the EGR control valve is expected. Even when the response of the vane is slower than the intended response, the actual supercharging pressure can be controlled to the target supercharging pressure with a predetermined followability, and the actual EGR rate can be set to the target EGR. The rate can be controlled with a predetermined followability, or at least the actual boost pressure and the actual EGR rate can be controlled in good balance with the target boost pressure and the target EGR rate, respectively.

The first correction value used for correcting the proportional gain is the target boost pressure when the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value. The followability can be set to a value that can reach the predetermined followability as early as possible and the target EGR rate followability is not lower than the predetermined followability.

Further, the correction of the proportional gain using the first correction value is that the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value. It is performed that the response of the EGR control valve is an expected response later than the intended response. In other words, the vane manipulated variable proportional gain and the EGR control valve manipulated variable proportional gain are corrected without considering how much the boost pressure deviation accumulated value and the EGR rate deviation accumulated value deviate from their reference values. . Therefore, the first correction value is obtained by correcting the target boost pressure follow-up significantly beyond the predetermined follow-up by the correction of the one-time vane manipulated variable proportional gain and the EGR control valve manipulated variable proportional gain, and the target EGR rate follow-up. It is considered that it is preferable to set the value to such a small value that the performance does not greatly exceed the predetermined followability.

In the first embodiment, the correction of the proportional gain is performed from the viewpoint of simplifying the correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain and correcting the proportional gain in a balanced manner. The same first correction value is used as the correction value. However, if necessary, the correction values for correcting each proportional gain may be different from each other.

In the first embodiment, the gain is corrected by adding the first correction value to the vane operation amount proportional gain. However, if necessary, a specific value larger than 1 is set to a vane operation amount proportional gain. The gain may be corrected by multiplying by. In the first embodiment, the gain is corrected by subtracting the first correction value from the EGR control valve operation amount proportional gain. However, if necessary, a specific value smaller than 1 is set to an EGR control valve. The gain may be corrected by multiplying the manipulated variable proportional gain. In this case, in terms of correcting these proportional gains in a well-balanced manner, the specific values multiplied by these proportional gains are set such that the sum of the specific values becomes a constant value, or It is considered preferable that the ratio of the values is set to a constant value.

Further, when the response of the EGR control valve is slower than the intended response although the vane response is the intended response, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate The deviation integrated value becomes larger than the reference value. Next, this will be described.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the exhaust pressure increases due to the decrease in the vane opening and the exhaust pressure due to the decrease in the EGR control valve opening. As a result, the boost pressure is increased. Here, when the response of the EGR control valve is slower than the intended response although the response of the vane is the intended response, the exhaust pressure increase rate due to the decrease in the vane opening is the expected speed. In spite of this, the exhaust pressure increase rate due to the decrease in the opening degree of the EGR control valve becomes slower than the intended speed. For this reason, as a whole, the increase speed of the supercharging pressure becomes slower than the intended speed. Therefore, when the actual boost pressure is to be increased when the response of the EGR control valve is slower than the expected response even though the vane response is the expected response, the boost pressure deviation integrated value is It becomes larger than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the EGR gas increases due to the decrease in the vane opening and the EGR gas due to the decrease in the EGR control valve opening. A decrease in volume occurs at the same time. Here, when the response of the EGR control valve is slower than the intended response although the response of the vane is the intended response, the increase rate of the EGR gas amount due to the decrease in the vane opening is the desired response. Regardless of the speed, the rate of decrease in the amount of EGR gas caused by the decrease in the opening degree of the EGR control valve becomes slower than the intended rate. For this reason, as a whole, the rate of decrease in the amount of EGR gas becomes slower than the intended rate. Therefore, when the actual EGR rate is to be lowered when the response of the EGR control valve is slower than the intended response even though the vane response is the intended response, the EGR rate deviation integrated value is the reference value. Larger than the value.

Further, when the target supercharging pressure is lowered, the target EGR rate is raised. Accordingly, at this time, the vane opening is increased in order to decrease the actual supercharging pressure toward the target supercharging pressure, and at the same time, the EGR control valve opening is increased in order to increase the actual EGR rate toward the target EGR rate. Is also enlarged.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the exhaust pressure decreases due to the increase in the vane opening and the exhaust pressure due to the increase in the EGR control valve opening. As a result, the supercharging pressure is reduced. Here, when the response of the EGR control valve is slower than the intended response although the response of the vane is the intended response, the rate of decrease in the exhaust pressure due to the increase in the vane opening is the desired rate. In spite of this, the exhaust pressure reduction rate due to the increase in the EGR control valve opening becomes slower than the intended rate. For this reason, as a whole, the decrease speed of the supercharging pressure becomes slower than the intended speed. Therefore, when the actual supercharging pressure is to be reduced when the response of the EGR control valve is slower than the intended response even though the vane response is the intended speed, the supercharging pressure deviation integrated value is It becomes larger than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the EGR gas is decreased due to the increase in the vane opening and the EGR gas is increased due to the increase in the EGR control valve opening. An increase in quantity occurs simultaneously. Here, when the response of the EGR control valve is slower than the intended response even though the response of the vane is the intended response, the rate of decrease in the EGR gas amount due to the increase in the vane opening is the desired response. Regardless of the speed, the increase rate of the EGR gas amount due to the increase in the opening degree of the EGR control valve becomes slower than the intended speed. For this reason, as a whole, the rate of increase in the amount of EGR gas is slower than the intended rate. Therefore, when the actual EGR rate is to be increased when the response of the EGR control valve is slower than the intended response even though the vane response is the intended response, the EGR rate deviation integrated value is the reference value. Larger than the value.

As described above, when the response of the EGR control valve is slower than the intended response although the vane response is the intended response, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation The integrated value becomes larger than the reference value.

Here, if the operation amount of the EGR control valve is increased, the response of the EGR control valve becomes faster. Therefore, when the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, if the EGR control valve operation amount is increased, the response of the EGR control valve becomes faster. As a result, the deviation speed of the actual EGR rate approaches the intended speed. Therefore, in the first embodiment, in this case, the EGR control valve operation amount proportional gain is multiplied by the second correction value so that the EGR control valve operation amount proportional gain is increased. Thus, if the EGR control valve operation amount proportional gain is increased, the set target EGR control valve operation amount is increased. According to this, the response of the EGR control valve becomes faster, and as a result, the rate change rate of the actual EGR becomes faster and approaches the intended speed. Then, if the correction of the EGR control valve operation amount proportional gain is repeated, the actual EGR rate change speed finally reaches the intended speed. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

On the other hand, if the vane operation amount is increased, the response of the vanes becomes faster. Therefore, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, if the vane operation amount is increased, the response of the vane becomes faster. The change speed of the actual supercharging pressure approaches the expected speed. Therefore, in the first embodiment, in this case, the vane operation amount proportional gain is multiplied by the second correction value so that the vane operation amount proportional gain is increased. Thus, if the vane operation amount proportional gain is increased, the set target vane operation amount is increased. According to this, the response of the vane becomes faster, and as a result, the change speed of the actual supercharging pressure becomes faster and approaches the intended speed. If the correction of the vane operation amount gain is repeated, the change speed of the actual supercharging pressure finally reaches the intended speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

In addition, according to the correction of the EGR control valve operation amount proportional gain using the second correction value described above, the response of the EGR control valve becomes faster, so that the change of the exhaust pressure due to the change of the EGR control valve opening degree is reduced. The speed is slow. Also from this, the change speed of the actual supercharging pressure increases and approaches the expected speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure earlier.

Thus, according to the first embodiment, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, and therefore the vane response is the desired response. Nevertheless, even when the response of the EGR control valve is slower than the intended response, the actual boost pressure can be controlled with a predetermined follow-up to the target boost pressure and the actual EGR rate can be set to the target EGR rate. The rate can be controlled with a predetermined followability, or the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively.

Note that the second correction value used for correcting the proportional gain is the target boost pressure when the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value. The followability can be set to a value that can reach the predetermined followability as early as possible and the target EGR rate followability can reach the predetermined followability as early as possible.

Further, the correction of the proportional gain using the second correction value is based on the fact that the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value. The predetermined response is performed when the response of the EGR control valve is slower than the predetermined response. In other words, the vane manipulated variable proportional gain and the EGR control valve manipulated variable proportional gain are corrected without considering how much the boost pressure deviation accumulated value and the EGR rate deviation accumulated value deviate from their reference values. . Therefore, the second correction value does not increase the target boost pressure follow-up performance and the target EGR rate follow-up performance greatly beyond the predetermined follow-up performance by correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain once. It is considered preferable to set a value as small as possible.

In the first embodiment, the correction of the proportional gain is performed from the viewpoint of simplifying the correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain and correcting the proportional gain in a well-balanced manner. The same second correction value is used as the correction value. However, if necessary, the correction values for correcting each proportional gain may be different from each other.

In the first embodiment, the gain is corrected by multiplying the vane operation amount proportional gain by the second correction value. However, if necessary, a specific value is set so that the vane operation amount proportional gain is increased. May be added to the vane manipulated variable proportional gain to correct the gain. In the first embodiment, the EGR control valve operation amount proportional gain is corrected by multiplying the second correction value by the EGR control valve operation amount proportional gain. However, if necessary, the EGR control valve operation amount proportional gain is increased. Alternatively, the gain may be corrected by adding a specific value to the EGR control valve operation amount proportional gain. In this case, from the viewpoint of correcting these proportional gains in a well-balanced manner, it is considered preferable that specific values added to these proportional gains are set to the same value.

Further, when the response of the vane is slower than the intended response and the response of the EGR control valve is also slower than the intended response, the supercharging pressure deviation integrated value is larger than the reference value (in detail, The EGR rate deviation integrated value is larger than the supercharging pressure deviation integrated value when the response of the EGR control valve is slower than the intended response although the vane response is the desired response). Is approximately equal to the reference value (or, in some cases, is equal to the reference value). Next, this will be described.

That is, when the target supercharging pressure is increased, the target EGR rate is decreased. Therefore, at this time, the vane opening is made small in order to increase the actual supercharging pressure toward the target supercharging pressure, and at the same time, the EGR control valve opening is used to decrease the actual EGR rate toward the target EGR rate. Is also made smaller.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the exhaust pressure increases due to the decrease in the vane opening and the exhaust pressure due to the decrease in the EGR control valve opening. As a result, the boost pressure is increased. Here, when the response of the vane and the response of the EGR control valve are slower than the intended response, the exhaust pressure increase rate due to the decrease in the vane opening degree also increases the exhaust pressure due to the decrease in the EGR control valve opening degree. The speed is also slower than the intended speed. For this reason, the increasing speed of the supercharging pressure is significantly slower than the intended speed. Therefore, when the actual supercharging pressure is to be increased when both the vane response and the EGR control valve response are slower than the intended response, the supercharging pressure deviation integrated value becomes significantly larger than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the EGR gas increases due to the decrease in the vane opening and the EGR gas due to the decrease in the EGR control valve opening. A decrease in volume occurs at the same time. Here, when both the response of the vane and the response of the EGR control valve are slower than the intended response, the increase rate of the EGR gas amount due to the decrease in the vane opening degree is also the EGR gas amount due to the decrease in the EGR control valve opening degree. The rate of decrease of is also slower than the expected rate. For this reason, the decrease in the increase rate of the EGR gas amount due to the decrease in the vane opening degree and the decrease in the decrease rate of the EGR gas amount due to the decrease in the EGR control valve opening amount cancel each other. The rate of decrease in the EGR rate is substantially the expected rate, and in some cases, the expected rate. Therefore, when the actual EGR rate is to be reduced when both the vane response and the EGR control valve response are slower than the intended response, the EGR rate deviation integrated value becomes substantially equal to the reference value (or in some cases Is equal to its reference value).

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the exhaust pressure decreases due to the increase in the vane opening and the exhaust pressure due to the increase in the EGR control valve opening. As a result, the supercharging pressure is reduced. Here, when the response of the vane and the response of the EGR control valve are slower than the intended response, the exhaust pressure decrease rate due to the increase in the vane opening degree also decreases the exhaust pressure due to the increase in the EGR control valve opening degree. The speed is also slower than the intended speed. For this reason, as a whole, the decrease rate of the supercharging pressure is significantly slower than the intended speed. Therefore, when the actual supercharging pressure is to be reduced when both the vane response and the EGR control valve response are slower than the intended response, the supercharging pressure deviation integrated value becomes significantly larger than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the EGR gas is decreased due to the increase in the vane opening and the EGR gas is increased due to the increase in the EGR control valve opening. An increase in quantity occurs simultaneously. Here, when the response of the vane and the response of the EGR control valve are slower than the intended response, the rate of decrease in the EGR gas amount due to the increase in the vane opening is also the amount of EGR gas due to the increase in the EGR control valve opening. The increase speed of the speed is also slower than the expected speed. For this reason, the decrease in the decrease rate of the EGR gas amount due to the increase in the vane opening degree and the decrease in the increase rate of the EGR gas amount due to the increase in the EGR control valve opening amount are offset, and as a result, as a whole The rate of decrease in the EGR rate is substantially the expected rate, and in some cases, the expected rate. Therefore, when the actual EGR rate is to be reduced when both the vane response and the EGR control valve response are slower than the intended response, the EGR rate deviation integrated value becomes substantially equal to the reference value (or in some cases Is equal to its reference value).

As described above, when the response of the vane and the response of the EGR control valve are slower than the intended response, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value becomes the reference value. It is approximately equal (or equal to the reference value).

Here, if the amount of vane operation is increased, the response of the vanes becomes faster. Therefore, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, if the vane operation amount is increased, the response of the vane becomes faster. The change speed of the actual supercharging pressure approaches the intended speed. Therefore, in the first embodiment, in this case, the third correction value is multiplied by the vane operation amount proportional gain so that the vane operation amount proportional gain is increased. Thus, if the vane operation amount proportional gain is increased, the set target vane operation amount is increased. According to this, the response of the vane becomes faster, and as a result, the change speed of the actual supercharging pressure becomes faster and approaches the intended speed. Then, if the correction of the vane operation amount proportional gain is repeated, the change speed of the actual supercharging pressure finally reaches the intended speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

On the other hand, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, it is considered that the actual EGR rate is controlled to the target EGR rate with a predetermined followability. be able to. However, as described above, in this case, since the vane operation amount proportional gain is increased and the response of the vane is accelerated, the EGR gas amount caused by the change in the vane opening (that is, the increase or decrease in the vane opening). Change rate (that is, the rate of decrease or increase of the EGR gas amount) becomes faster. In this case, the target EGR rate followability becomes lower than the predetermined followability. On the other hand, if the operation amount of the EGR control valve is increased, the response of the EGR control valve becomes faster, so that it is possible to suppress the target EGR rate tracking performance from becoming lower than the predetermined tracking performance. Therefore, in the first embodiment, when the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, the EGR control valve operation amount proportional gain is increased. The third correction value is multiplied by the EGR control valve operation amount proportional gain. Thus, if the EGR control valve operation amount proportional gain is increased, the set target EGR control valve operation amount is increased. For this reason, it can suppress that target EGR rate followability becomes lower than predetermined followability. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

In addition, according to the correction of the EGR control valve operation amount proportional gain using the third correction value described above, the response of the EGR control valve becomes faster, so that the change in the exhaust pressure caused by the change in the EGR control valve opening degree is reduced. Increases speed. Also from this, the change speed of the actual supercharging pressure increases and approaches the expected speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure earlier.

Thus, according to the first embodiment, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, and therefore the vane response is also the response of the EGR control valve. Even when the response is slower than the intended response, the actual supercharging pressure can be controlled to the target supercharging pressure with a predetermined followability, and the actual EGR rate can be controlled to the target EGR rate with a predetermined followability. Alternatively, the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively.

The third correction value used for correcting the proportional gain is the target boost pressure when the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value. The followability can be set to a value that can reach the predetermined followability as early as possible, and the target EGR rate followability can reach the predetermined followability as early as possible.

Further, the correction of the proportional gain using the third correction value is based on the fact that the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value. This is performed with a slower response than the predetermined response and a response of the EGR control valve slower than the predetermined response. In other words, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected without considering how much the accumulated value of the supercharging pressure deviation deviates from the reference value. Therefore, the third correction value does not increase the target boost pressure follow-up performance and the target EGR rate follow-up performance greatly beyond the predetermined follow-up performance by correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain once. It is considered preferable to set a value as small as possible.

In the first embodiment, the correction of the proportional gain is performed from the viewpoint of simplifying the correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain and correcting the proportional gain in a well-balanced manner. The correction value is the same third correction value. However, if necessary, the correction values for correcting each proportional gain may be different from each other.

In the first embodiment, the gain is corrected by multiplying the vane operation amount proportional gain by the third correction value. However, if necessary, a specific value is set so that the vane operation amount proportional gain is increased. May be added to the vane manipulated variable proportional gain to correct the gain. In the first embodiment, the gain is corrected by multiplying the EGR control valve operation amount proportional gain by the third correction value. However, if necessary, the EGR control valve operation amount proportional gain is increased. Alternatively, the gain may be corrected by adding a specific value to the EGR control valve operation amount proportional gain. In this case, from the viewpoint of correcting these proportional gains in a well-balanced manner, it is considered preferable that specific values added to these proportional gains are set to the same value.

In the first embodiment, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected based on the deviation of the supercharging pressure deviation integrated value with respect to the reference value and the deviation of the EGR rate deviation integrated value with respect to the reference value. The Therefore, in the first embodiment, the target vane operation amount and the target EGR control valve operation amount are corrected so that the supercharging pressure deviation integrated value matches the reference value and the EGR rate deviation integrated value matches the reference value. It can be said that it is a thing.

In the first embodiment, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected based on the boost pressure deviation integrated value and the EGR rate deviation integrated value. Instead of or in addition to the above, the integral gain, differential gain, or integral gain and differential gain of the above equation 1 may be corrected, and instead of or in addition to the correction of the EGR control valve operation amount proportional gain. The integral gain or differential gain of the above equation 2 or the integral gain and the differential gain may be corrected.

Further, in the first embodiment, in an internal combustion engine including a supercharger that controls a supercharging pressure and an EGR device that controls an EGR rate, the supercharging pressure and the EGR rate are converted into a target supercharging pressure and a target EGR rate. This is an embodiment to which the present invention is applied in order to control with a predetermined followability, or when controlling the supercharging pressure and the EGR rate in a balanced manner with respect to the target supercharging pressure and the target EGR rate. However, the idea of the present invention described in relation to the first embodiment is that, in an internal combustion engine provided with a control object that controls two control amounts that influence each other, these two control amounts are set as target control amounts, respectively. The present invention can also be applied to control with a predetermined followability, or to control these two control amounts in a balanced manner with respect to the target control amount.

In consideration of the above, the control device for an internal combustion engine of the present invention described in relation to the first embodiment has a first control amount (for example, a first control amount) that is one of two control amounts that influence each other. The first control object (for example, the vane of the first embodiment) that controls the supercharging pressure of the embodiment and the second control amount (for example, the first control amount that is the remaining one of the two control amounts that influence each other). In a control device for an internal combustion engine including a second control target (for example, an EGR control valve according to the first embodiment) that controls an EGR rate according to the first embodiment, a target first control amount is set as a target first control amount Set as the amount (for example, the target boost pressure of the first embodiment) and the second control amount to be targeted is set as the target second control amount (for example, the target EGR rate of the first embodiment), and the first The control amount is made to reach the target first control amount, and the second control amount is set to the target second. The operation amount to be input to the first control object in order to reach the control amount is set as the target first operation amount (for example, the target vane operation amount of the first embodiment) and the operation amount to be input to the second control object Is set as the target second operation amount (for example, the target EGR control valve operation amount of the first embodiment), and the operation amount corresponding to the target first operation amount is input to the first control target and the target second operation amount is set. A control device that controls a first control amount to a target first control amount by inputting a corresponding operation amount to a second control target, and controls the second control amount to a target second control amount, during engine operation In addition, the integrated value of the deviation of the actual first control amount with respect to the target first control amount is calculated as the first control amount deviation integrated value (for example, the boost pressure deviation integrated value of the first embodiment) and the target second control amount. Integrated value of deviation of actual second controlled variable with respect to A second control amount deviation integrated value (for example, an EGR rate deviation integrated value of the first embodiment) is calculated, and a target first operation is performed based on the first control amount deviation integrated value and the second control amount deviation integrated value. It can be said that the control device corrects the amount and the target second operation amount.

Also, the supercharging pressure and the EGR rate are control amounts that affect the emissions discharged from the internal combustion engine. Accordingly, the control of the internal combustion engine structure and the internal combustion engine is based on the premise that the supercharging pressure is controlled with a predetermined followability to the target supercharging pressure and the EGR rate is controlled with a predetermined followability to the target EGR rate. It has been decided to reduce emissions as much as possible. Here, in the first embodiment, even when at least one of the response of the vane and the response of the EGR control valve becomes slower than the intended response, the supercharging pressure follows the target supercharging pressure for a predetermined amount. And the EGR rate is controlled with a predetermined followability to the target EGR rate. Therefore, according to the first embodiment, the emission discharged from the internal combustion engine is reliably maintained at a low level.

Further, in the first embodiment, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, the response of the EGR control valve is an intended response, and the target Although the EGR rate followability is higher than the predetermined followability, the response of the EGR control valve is delayed by reducing the EGR control valve operation amount proportional gain. According to this, even if temporarily, the target EGR rate followability may be lower than the predetermined followability. However, the reason why the response of the EGR control valve is delayed in this way is determined that it is appropriate to delay the response of the EGR control valve in order to improve the target boost pressure tracking performance to a predetermined tracking performance. Because it was done. In other words, it can be said that priority was given to improving the target boost pressure followability rather than maintaining the target EGR rate followability high. That is, according to the first embodiment, it can be said that it can be determined which of the target boost pressure followability and the target EGR rate followability is prioritized.

Next, an example of a routine for setting the target vane operation amount and the target EGR control valve operation amount according to the first embodiment will be described. This routine is shown in FIG. 4 and is executed at predetermined time intervals.

4 is started, first, at step 10, the engine speed N, the engine load L, the current boost pressure Pim, and the current EGR rate Regr are acquired. Next, at step 11, the target boost pressure TPim is acquired from the target boost pressure map of FIG. 3A based on the engine speed N and the engine load L acquired at step 10, and at step 10, Based on the acquired engine speed N and engine load L, the target oxygen concentration TO2 is acquired from the target oxygen concentration map of FIG. Next, at step 12, the target EGR rate TRegr is calculated based on the current supercharging pressure Pim acquired at step 10 and the target oxygen concentration TO2 acquired at step 11. Next, in step 13, a deviation (ie, supercharging pressure deviation) ΔPim of the current supercharging pressure Pim acquired in step 10 with respect to the target supercharging pressure TPim acquired in step 11 is calculated, and in step 12. A deviation (ie, EGR rate deviation) ΔRegr of the current EGR rate Regr acquired in step 10 with respect to the calculated target EGR rate TRegr is calculated.

Next, at step 14, the supercharging pressure deviation ΔPim calculated at step 13 is added to the supercharging pressure deviation integrated value ΣΔPim stored at step 15 when the routine of FIG. The pressure deviation integrated value ΣΔPim is calculated, and the EGR rate deviation ΔRegr calculated in step 13 is added to the EGR rate deviation integrated value ΣΔRegr stored in step 15 when the routine of FIG. An EGR rate deviation integrated value ΣΔRegr is calculated. Next, in step 15, the new boost pressure deviation integrated value ΣΔPim calculated in step 14 and the new EGR rate deviation integrated value ΣΔRegr are stored.

Next, at step 16, the target vane operation amount Mv is calculated from the above equation 1 using the boost pressure deviation ΔPim calculated at step 13 and the boost pressure deviation integrated value ΣΔPim calculated at step 14. Using the EGR rate deviation ΔRegr calculated in step 13 and the EGR rate deviation integrated value ΣΔRegr calculated in step 14, the target EGR control valve operation amount Megr is calculated from the above equation 2, and the routine ends.

Next, an example of a routine for correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to the first embodiment will be described. This routine is shown in FIGS. 5 and 6, and is executed at predetermined time intervals.

When the routines of FIGS. 5 and 6 are started, first, at step 100, the current supercharging pressure deviation integrated value ΣΔPim (k) stored at step 15 of FIG. 4 and the current EGR rate deviation integrated value ΣΔRegr are stored. (K) is acquired. Next, in step 101, the current supercharging pressure deviation integrated value ΣΔPim (k) acquired in step 100 is larger than the reference value THpim (ΣΔPim (k)> THpim) and the current EGR acquired in step 100. Whether the rate deviation integrated value ΣΔRegr (k) is smaller than the lower limit value (that is, the value obtained by subtracting the predetermined value α from the reference value THegr) (THegr−α) (ΣΔRegr (k) <THegr−α). Determined. Here, when it is determined that ΣΔPim (k)> THpim and ΣΔRegr (k) <THegr−α, the routine proceeds to step 102. On the other hand, if it is determined that ΣΔPim (k)> THpim and ΣΔRegr (k) <THegr−α is not established, the routine proceeds to step 104.

Note that the value obtained by subtracting the predetermined value α from the reference value THegr of the EGR rate deviation integrated value is used as the lower limit value compared with the current EGR rate deviation integrated value ΣΔRegr (k) in step 101. In step 107 of FIG. 6, in order to determine whether the current EGR rate deviation integrated value ΣΔRegr (k) is substantially equal to the reference value THegr, a predetermined value α is subtracted from the reference value THegr of the EGR rate deviation integrated value. This is because the value is used. Further, since the lower limit value is used to determine whether or not the current EGR rate deviation integrated value ΣΔRegr (k) is substantially equal to the reference value, the predetermined value α is set to an extremely small value.

When it is determined in step 101 that ΣΔPim (k)> THpim and ΣΔRegr (k) <THegr−α, and the routine proceeds to step 102, the current vane manipulated variable proportional gain GPp (k) and the current EGR The control valve operation amount proportional gain GEp (k) is acquired. Next, in step 103, a value (GPp (k) + K1) obtained by adding the first correction value K1 to the current vane operation amount proportional gain GPp (k) acquired in step 102 is a new vane operation amount proportional. A value obtained by subtracting the first correction value K1 from the current EGR control valve operation amount proportional gain GEp (k) acquired in step 102 and being set to the gain GPp (k + 1) (GEp (k) −K1) ) Is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 103, and step 103 The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

On the other hand, when it is determined in step 101 that ΣΔPim (k)> THpim and ΣΔRegr (k) <THegr−α are not satisfied, and the routine proceeds to step 104, the current supercharging pressure deviation accumulated in step 100 is obtained. The value ΣΔPim (k) is larger than its reference value THpim (ΣΔPim (k)> THpim), and the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 100 is its upper limit value (that is, its reference value THegr). It is determined whether or not (ΣΔRegr (k)> THegr + α) is greater than (THegr + α), which is a value obtained by adding a predetermined value α to. Here, when it is determined that ΣΔPim (k)> THpim and ΣΔRegr (k)> THegr + α, the routine proceeds to step 105. On the other hand, if it is determined that ΣΔPim (k)> THpim and ΣΔRegr (k)> THegr + α is not established, the routine proceeds to step 107 in FIG.

Note that the value obtained by adding the predetermined value α to the reference value THegr of the EGR rate deviation integrated value is used as the upper limit value compared with the current EGR rate deviation integrated value ΣΔRegr (k) in step 104. In step 107 of FIG. 6, a predetermined value α is added to the reference value THegr of the EGR rate deviation integrated value to determine whether or not the current EGR rate deviation integrated value ΣΔRegr (k) is substantially equal to the reference value THegr. This is because the value is used. Further, since the upper limit value is used to determine whether or not the current EGR rate deviation integrated value ΣΔRegr (k) is substantially equal to the reference value, as described above, the predetermined value α is set to a very small value. Has been.

When it is determined in step 104 that ΣΔPim (k)> THpim and ΣΔRegr (k)> THegr + α, and the routine proceeds to step 105, the current vane operation amount proportional gain GPp (k) and the current EGR control valve The manipulated variable proportional gain GEp (k) is acquired. Next, in step 106, a value (GPp (k) × K2) obtained by multiplying the current vane operation amount proportional gain GPp (k) acquired in step 105 by the second correction value K2 is a new vane operation amount. A value obtained by multiplying the current EGR control valve operation amount proportional gain GEp (k) acquired in step 105 by the second correction value K2 while being set to the proportional gain GPp (k + 1) (GEp (k) × K2) is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 106, and step 106 The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

On the other hand, if it is determined in step 104 that ΣΔPim (k)> THpim and ΣΔRegr (k)> THegr + α is not established and the routine proceeds to step 107 in FIG. 6, the current boost pressure deviation obtained in step 100 is determined. The integrated value ΣΔPim (k) is larger than the reference value THpim (ΣΔPim (k)> THpim), and the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 100 is substantially equal to the reference value THegr, that is, The current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 100 is not less than the lower limit value (THegr−α) and not more than the upper limit value (THegr + α) (THegr−α ≦ ΣΔRegr (k)). It is determined whether or not ≦ THegr + α). Here, when it is determined that ΣΔPim (k)> THpim and THegr−α ≦ ΣΔRegr (k) ≦ THegr + α, the routine proceeds to step 108. On the other hand, when it is determined that ΣΔPim (k)> THpim and that THegr−α ≦ ΣΔRegr (k) ≦ THegr + α is not established, the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the current vane operation amount proportional gain GPp (k), and the current EGR control valve operation amount is proportional. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the gain GEp (k).

In step 107, it is determined that ΣΔPim (k)> THpim and THegr−α ≦ ΣΔRegr (k) ≦ THegr + α. When the routine proceeds to step 108, the current vane operation amount proportional gain GPp (k) and the current EGR control valve operation amount proportional gain GEp (k) is acquired. Next, in step 109, a value (GPp (k) × K3) obtained by multiplying the current vane operation amount proportional gain GPp (k) acquired in step 108 by the third correction value K3 is a new vane operation amount. A value obtained by multiplying the current EGR control valve operation amount proportional gain GEp (k) acquired in step 108 by the third correction value K3, while being set to the proportional gain GPp (k + 1) (GEp (k) × K3) is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 108, and step 108. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

Next, a second embodiment of the present invention will be described. As described above, in the first embodiment, the target vane operation amount and the target EGR control valve operation amount for setting the actual supercharging pressure to the target supercharging pressure and the EGR rate to the target EGR rate are expressed by the above equation 1 respectively. The operation amount corresponding to the calculated target vane operation amount is input to the vane 35D, and the operation amount corresponding to the calculated target EGR control valve operation amount is calculated using the EGR control. This is input to the valve 52, whereby the actual supercharging pressure is controlled to the target supercharging pressure and the actual EGR rate is controlled to the target EGR rate. On the other hand, in the second embodiment, the actual supercharging pressure is controlled to the target supercharging pressure by the control different from the control of the actual supercharging pressure and the actual EGR rate in the first embodiment, and the actual EGR rate is reduced. Controlled to the target EGR rate.

That is, in the second embodiment, the amount of change in the vane opening that should be the target in order to set the actual supercharging pressure to the target supercharging pressure and the actual EGR rate to the target EGR rate is calculated as the target vane opening change amount. The amount of change in the opening degree of the EGR control valve to be targeted is calculated as the target amount of change in the opening degree of the EGR control valve. Then, using a target vane opening change amount conversion formula (that is, a conversion formula determined in advance to calculate the target vane opening change amount corresponding to the target vane opening change amount from the target vane opening change amount). A target vane operation amount is calculated from the calculated target vane opening change amount, and a target EGR control valve operation amount corresponding to the target EGR control valve opening change amount is calculated from the target EGR control valve opening change amount. Therefore, the target EGR control valve operation amount is calculated from the calculated target EGR control valve opening change amount using a predetermined conversion equation). An operation amount corresponding to the calculated target vane operation amount is input from the electronic control device 60 to the vane 35D, and an operation amount corresponding to the calculated target EGR control valve operation amount is input from the electronic control device 60. Input to the EGR control valve 52. As a result, the actual boost pressure is controlled to the target boost pressure, and the actual EGR rate is controlled to the target EGR rate.

Next, setting of the target vane opening change amount according to the second embodiment will be described. In the second embodiment, PID control using the supercharging pressure deviation is used for setting the target vane opening change amount. Specifically, the actual supercharging pressure is acquired during engine operation, and a deviation (that is, a supercharging pressure deviation) of the acquired actual supercharging pressure with respect to the target supercharging pressure is calculated. Then, the supercharging pressure deviation integrated value is calculated by integrating the supercharging pressure deviation thus calculated.

The supercharging pressure deviation calculated as described above is represented by “ΔPim”, the supercharging pressure deviation integrated value calculated as described above is represented by “ΣΔPim”, and the target vane opening change amount is represented by “TDv”. When the proportional gain in PID control is represented by “GPp”, the integral gain in PID control is represented by “GPi”, and the differential gain in PID control is represented by “GPd”, the change in target vane opening according to the following equation 3 A quantity TDv is calculated (ie set).
TDv = GPp × ΔPim + GPi × ΣΔPim + GPd × d (ΔPim) / dt (3)

As described above, in the second embodiment, the target vane opening change amount corresponding to the target vane opening change amount calculated from the above equation 3 is calculated from the target vane opening change amount conversion formula, and this calculation is performed. An operation amount corresponding to the target vane operation amount is input from the electronic control device 60 to the vane 35D.

Next, the setting of the target EGR control valve opening change amount according to the second embodiment will be described. In the second embodiment, PID control using the EGR rate deviation is used for setting the target EGR control valve opening change amount. Specifically, the actual EGR rate is acquired during engine operation, and a deviation (that is, EGR rate deviation) of the acquired actual EGR rate with respect to the target EGR rate is calculated. Then, the EGR rate deviation integrated value is calculated by integrating the EGR rate deviation thus calculated.

The EGR rate deviation calculated as described above is represented by “ΔRegr”, the EGR rate deviation integrated value calculated as described above is represented by “ΣΔRegr”, and the target EGR control valve opening change amount is represented by “TDegr”. When the proportional gain in PID control is represented by “GEp”, the integral gain in PID control is represented by “GEi”, and the differential gain in PID control is represented by “GEd”, the target EGR control valve is opened according to the following equation 4. A degree change amount TDegr is calculated.
TDegr = GPp × ΔRegr + GPi × ΣΔRegr + GPd × d (ΔRegr) / dt (4)

As described above, in the second embodiment, the target EGR control valve operation amount corresponding to the target EGR control valve opening change amount calculated from the above equation 4 is calculated from the target EGR control valve opening change amount conversion equation. Then, an operation amount corresponding to the calculated target EGR control valve operation amount is input from the electronic control device 60 to the EGR control valve 52.

By the way, in the second embodiment, in order to control the actual supercharging pressure with the target supercharging pressure with a predetermined followability and to control the actual EGR rate with the predetermined followability with the target EGR rate, The proportional gain of Equation 3 used for setting the change amount (hereinafter, this gain is referred to as “vane opening proportional gain”) and the proportional gain of Equation 4 used for setting the target EGR opening change amount (hereinafter referred to as this gain). The gain is referred to as “EGR control valve opening proportional gain”) is corrected based on the supercharging pressure deviation integrated value and the EGR rate deviation integrated value, and the corrected vane opening proportional gain is the proportional gain of Equation 3 above. Is used to set the target vane opening change amount, and the corrected EGR control valve opening proportional gain is used as the proportional gain of Equation 4 to set the target EGR control valve change amount. In other words, in the second embodiment, the vane opening proportional gain and the EGR control valve opening proportional gain are learned based on the boost pressure deviation integrated value and the EGR rate deviation integrated value, and these are learned. The vane opening proportional gain and the EGR control valve proportional gain are used for setting the target vane opening change amount and setting the target EGR control valve opening change amount.

Next, correction of the vane opening proportional gain and the EGR control valve opening proportional gain based on the supercharging pressure deviation integrated value and the EGR rate deviation integrated value will be described.

In the second embodiment, the supercharging pressure deviation integrated value calculated during engine operation is compared with a reference value (that is, the reference value), and the EGR rate deviation integrated value calculated during engine operation. The value is compared with a certain reference value (ie its reference value).

Here, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, a predetermined value (hereinafter referred to as this value) is set so that the vane opening proportional gain is increased. Is added to the vane opening proportional gain, the gain is corrected and the EGR control valve opening is adjusted so that the EGR control valve opening proportional gain is reduced. By subtracting from the proportional gain, the gain is corrected.

Further, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, a predetermined value larger than 1 is set so that the EGR control valve opening proportional gain is increased. By multiplying the value (hereinafter referred to as “second correction value”) by the EGR control valve opening proportional gain, the second correction value is set so that the gain is corrected and the vane opening proportional gain is increased. The gain is corrected by multiplying the vane opening proportional gain.

Further, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to (or equal to) the reference value, the vane opening proportional gain is increased. The gain is corrected by multiplying the vane opening proportional gain by a predetermined value greater than 1 (hereinafter, this value is referred to as a “third correction value”) and the EGR control valve opening proportional gain is increased. As described above, the gain is corrected by multiplying the EGR control valve opening proportional gain by the third correction value.

Further, when the relationship between the supercharging pressure deviation integrated value with respect to the reference value and the relationship between the EGR rate deviation integrated value with respect to the reference value is other than the relationship mentioned above, the vane opening proportional gain is also set to open the EGR control valve. The degree proportional gain is not corrected.

Also in the second embodiment, for example, the supercharging pressure deviation integrated value and the EGR rate deviation integrated value that can be taken when the response of the vane is the highest and the response of the EGR control valve is the highest are obtained in advance through experiments or the like. The obtained values are used as a reference value for the supercharging pressure deviation integrated value and a reference value for the EGR rate deviation integrated value, respectively.

As described above, the vane opening proportional gain and the EGR control valve opening proportional gain are corrected, and these corrected gains are used for setting the target vane opening change amount and setting the target EGR control valve opening change amount, respectively. Then, the supercharging pressure can be controlled to the target supercharging pressure with a predetermined followability and the EGR rate can be controlled to the target EGR rate with a predetermined followability, or the actual supercharging. An effect is obtained that the pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target supercharging pressure and the target EGR rate, respectively.

That is, as described in relation to the first embodiment, the supercharging pressure and the EGR rate are control amounts that influence each other. Therefore, when the supercharging pressure is controlled by the supercharger 35, when the supercharging pressure is controlled with a predetermined followability to the target supercharging pressure, the same supercharging pressure by the supercharger 35 with respect to the supercharging pressure. Considering the influence of the control of the EGR rate by the EGR device 50 on the supercharging pressure as well as the influence of the control of the supercharging pressure is advantageous from the viewpoint of controlling the supercharging pressure to the target supercharging pressure with higher accuracy. There is. Further, when the EGR rate is controlled by the EGR device 50, the control of the EGR rate by the EGR device 50 on the EGR rate is taken into account when the EGR rate is to be controlled with a predetermined followability to the target EGR rate. In addition, considering the influence of the supercharging pressure control by the supercharger 35 on the EGR rate is advantageous from the viewpoint of controlling the EGR rate to the target EGR rate with higher accuracy.

Here, in general, the proportional gain, integral gain, and differential gain of Equation 3 are calculated from the target vane opening change amount TDv calculated from Equation 3 according to the target vane opening change amount conversion equation. A value such that a target vane opening change amount is calculated from the above equation 3 so that the supercharging pressure is appropriately controlled with a predetermined followability to the target supercharging pressure when an operation amount is input to the vane. It is calculated | required by experiment etc. previously. In this regard, as described above, since the supercharging pressure is affected by the EGR rate, a proportional gain, an integral gain, and a derivative gain (hereinafter referred to as “reference proportional gain”, “ It can be said that the “reference integral gain” and the “reference differential gain” are values based on the premise that the EGR rate is appropriately controlled with a predetermined followability to the target EGR rate. Therefore, the target vane opening change amount calculated from the above equation 3 that employs the reference proportional gain, the reference integral gain, and the reference differential gain is controlled with a predetermined followability of the supercharging pressure to the target supercharging pressure. The EGR rate is set on the assumption that the target EGR rate is controlled with a predetermined followability. Therefore, when the operation amount calculated based on the target vane opening change amount calculated from the above equation 3 using the reference proportional gain, the reference integral gain, and the reference differential gain is input to the vane, the boost pressure As long as the EGR rate is controlled with a predetermined followability to the target supercharging pressure and the EGR rate is controlled with a predetermined followability to the target EGR rate, the supercharging pressure has a predetermined followability to the target supercharging pressure. Be controlled.

In other words, when the supercharging pressure is not controlled with a predetermined followability to the target supercharging pressure, the target vane calculated from the above equation 3 adopting the reference proportional gain, the reference integral gain, and the reference differential gain. Even if an operation amount calculated based on the amount of change in opening is input to the vane, it is natural that the supercharging pressure is not controlled with a predetermined followability to the target supercharging pressure. Further, even when the EGR rate is not controlled with a predetermined followability to the target EGR rate, the target vane opening change amount calculated from the above equation 3 that employs the reference proportional gain, the reference integral gain, and the reference differential gain. Even if the operation amount calculated based on the above is input to the vane, the supercharging pressure is not controlled with a predetermined followability to the target supercharging pressure.

Similarly, in general, the proportional gain, integral gain, and differential gain of the above equation 4 are converted from the target EGR control valve opening change amount TDegr calculated from the above equation 4 to the target EGR control valve opening change amount. The target EGR control valve opening change amount that the EGR rate is appropriately controlled with a predetermined followability to the target EGR rate when the operation amount calculated according to the equation is input to the EGR control valve from the above equation 4. As a value to be calculated, it is obtained in advance by experiments or the like. In this regard, since the EGR rate is affected by the supercharging pressure as described above, the proportional gain, integral gain, and derivative gain (hereinafter referred to as “reference proportional gain”, “ It can also be said that the “reference integral gain” and “reference differential gain” are values based on the premise that the supercharging pressure is appropriately controlled with a predetermined followability to the target supercharging pressure. Accordingly, the target EGR control valve opening change amount calculated from the above equation 4 that employs the reference proportional gain, the reference integral gain, and the reference differential gain is controlled by the EGR rate with a predetermined followability to the target EGR rate. In addition, the supercharging pressure is set on the premise that the supercharging pressure is controlled with a predetermined followability to the target supercharging pressure. Therefore, when the operation amount calculated based on the target EGR control valve opening change amount calculated from the above equation 4 adopting the reference proportional gain, the reference integral gain, and the reference differential gain is input to the EGR control valve. As long as the EGR rate is controlled with a predetermined followability to the target EGR rate and the supercharging pressure is controlled with a predetermined followability to the target supercharging pressure, the EGR rate has a predetermined followability to the target EGR rate. So it is controlled.

In other words, when the EGR rate is not controlled with a predetermined followability to the target EGR rate, the target EGR control valve calculated from the above equation 4 adopting the reference proportional gain, the reference integral gain, and the reference differential gain. Even if the operation amount calculated based on the amount of change in opening is input to the EGR control valve, it is natural that the EGR rate is not controlled with a predetermined followability to the target EGR rate. Further, even when the supercharging pressure is not controlled with a predetermined followability to the target supercharging pressure, the target EGR control valve calculated from the above equation 4 that employs the reference proportional gain, the reference integral gain, and the reference differential gain. Even if the operation amount calculated based on the opening change amount is input to the EGR control valve, the EGR rate is not controlled with a predetermined followability to the target EGR rate.

Here, as explained in relation to the first embodiment, when the response of the vane is slower than the intended response although the response of the EGR control valve is the intended response, supercharging The pressure deviation integrated value is larger than the reference value, and the EGR rate deviation integrated value is smaller than the reference value.

Here, if the amount of vane operation is increased, the response of the vanes becomes faster. Therefore, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, if the vane operation amount is increased, the response of the vane becomes faster. The actual turbocharging pressure change speed (that is, the actual turbocharging pressure increasing speed when increasing the actual turbocharging pressure, or the actual turbocharging pressure decreasing speed when decreasing the actual turbocharging pressure) It will approach speed. Therefore, in the second embodiment, in this case, the first correction value is added to the vane opening proportional gain so that the vane opening proportional gain is increased. When the vane opening proportional gain is increased in this way, the set target vane opening change amount increases, and therefore the target vane operation amount calculated based on the target vane opening change amount also increases. According to this, the response of the vane becomes faster, and as a result, the change speed of the actual supercharging pressure becomes faster and approaches the intended speed. If the correction of the vane opening proportional gain is repeated, the change speed of the actual supercharging pressure finally reaches the desired speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

On the other hand, if the operation amount of the EGR control valve is reduced, the response of the EGR control valve is delayed. Therefore, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, if the EGR control valve operation amount is reduced, the response of the EGR control valve is delayed. As a result, the change rate of the actual EGR rate (that is, the decrease rate of the actual EGR rate when the actual EGR rate is decreased or the increase rate of the actual EGR rate when the actual EGR rate is increased) is an intended rate. Will approach. Therefore, in the second embodiment, in this case, the first correction value is subtracted from the EGR control valve opening proportional gain so that the EGR control valve opening proportional gain becomes small. If the EGR control valve opening proportional gain is reduced in this way, the set target EGR control valve opening change amount becomes small, and therefore, the target EGR control calculated based on the target EGR control valve opening change amount. The valve operation amount is also reduced. According to this, the response of the EGR control valve becomes slow, and as a result, the change speed of the actual EGR rate becomes slow and approaches the intended speed. If the correction of the EGR control valve opening proportional gain is repeated, finally, the actual EGR rate change speed reaches the desired speed. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

In addition, according to the correction of the vane opening proportional gain using the first correction value described above, the response of the vane becomes faster, so that the rate of change in the EGR gas amount due to the change in the vane opening becomes faster. Also from this, the rate of change of the actual EGR rate becomes slow and approaches the intended rate. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate earlier.

Thus, according to the second embodiment, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, and therefore the response of the EGR control valve is expected. Even when the response of the vane is slower than the intended response, the actual supercharging pressure can be controlled to the target supercharging pressure with a predetermined followability and the actual EGR rate can be set to the target EGR. The rate can be controlled with a predetermined followability, or the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively.

The first correction value used for correcting the vane opening proportional gain and the EGR control valve opening proportional gain is set based on the same concept as that for setting the first correction value in the first embodiment. The

Further, as described in relation to the first embodiment, when the response of the EGR control valve is slower than the intended response although the vane response is the intended response, the boost pressure The integrated deviation value is larger than the reference value, and the EGR rate deviation integrated value is larger than the reference value.

Here, if the operation amount of the EGR control valve is increased, the response of the EGR control valve becomes faster. Therefore, when the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, if the EGR control valve operation amount is increased, the response of the EGR control valve becomes faster. As a result, the deviation speed of the actual EGR rate approaches the intended speed. Therefore, in the second embodiment, in this case, the EGR control valve opening proportional gain is multiplied by the second correction value so that the EGR control valve opening proportional gain is increased. Thus, if the EGR control valve opening proportional gain is increased, the set target EGR control valve opening change amount is increased, and therefore the target EGR control calculated based on the target EGR control valve opening change amount is increased. The valve operation amount is also increased. According to this, the response of the EGR control valve becomes faster, and as a result, the change speed of the actual EGR becomes faster and approaches the intended speed. If the correction of the EGR control valve opening proportional gain is repeated, finally, the actual EGR rate change speed reaches the desired speed. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

On the other hand, if the vane operation amount is increased, the response of the vanes becomes faster. Therefore, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, if the vane operation amount is increased, the response of the vane becomes faster. The change speed of the actual supercharging pressure approaches the intended speed. Therefore, in the second embodiment, in this case, the vane opening proportional gain is multiplied by the second correction value so that the vane opening proportional gain is increased. If the vane opening proportional gain is increased in this way, the set target vane opening change amount increases, and therefore the target vane operation amount calculated based on the target vane opening change amount also increases. According to this, the response of the vanes becomes faster, and as a result, the change speed of the actual supercharging pressure becomes faster and approaches the intended speed. If the correction of the vane opening gain is repeated, finally, the change speed of the actual supercharging pressure reaches the intended speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

In addition, according to the correction of the EGR control valve opening proportional gain using the second correction value described above, the response of the EGR control valve becomes faster, so that the change in the exhaust pressure due to the change in the EGR control valve opening is reduced. The speed is slow. Also from this, the change speed of the actual supercharging pressure increases and approaches the expected speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure earlier.

Thus, according to the second embodiment, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, and therefore the vane response is the expected response. Even when the response of the EGR control valve is slower than the intended response, the actual supercharging pressure can be controlled with a predetermined followability to the target supercharging pressure and the actual EGR rate can be set to the target EGR. The rate can be controlled with a predetermined followability, or the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively.

The second correction value used for correcting the vane opening proportional gain and the EGR control valve opening proportional gain is set based on the same concept as that for setting the second correction value in the first embodiment. The

Further, as described in connection with the first embodiment, when the response of the vane is slower than the intended response and the response of the EGR control valve is also slower than the intended response, the boost pressure deviation integration is performed. Value is larger than the reference value (specifically, the supercharging pressure when the response of the EGR control valve is slower than the intended response although the vane response is the intended response) The EGR rate deviation integrated value becomes substantially equal to the reference value (or, in some cases, becomes equal to the reference value).

Here, if the amount of vane operation is increased, the response of the vanes becomes faster. Therefore, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, if the vane operation amount is increased, the response of the vane becomes faster. The change speed of the actual supercharging pressure approaches the intended speed. Therefore, in the second embodiment, in this case, the vane opening proportional gain is multiplied by the third correction value so that the vane opening proportional gain is increased. When the vane opening proportional gain is increased in this way, the set target vane opening change amount increases, and therefore the target vane operation amount calculated based on the target vane opening change amount also increases. According to this, the response of the vane becomes faster, and as a result, the change speed of the actual supercharging pressure becomes faster and approaches the intended speed. If the correction of the vane opening proportional gain is repeated, the change speed of the actual supercharging pressure finally reaches the desired speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

On the other hand, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, it is considered that the actual EGR rate is controlled to the target EGR rate with a predetermined followability. be able to. However, as described above, in this case, since the vane opening proportional gain is increased and the response of the vane is accelerated, the amount of EGR gas caused by the change in the vane opening (that is, the increase or decrease in the vane opening). Change rate (that is, the rate of decrease or increase of the EGR gas amount) becomes faster. In this case, the target EGR rate followability becomes lower than the predetermined followability. On the other hand, if the EGR control valve operation amount is increased, the response of the EGR control valve becomes faster, so that it is possible to suppress the target EGR rate tracking performance from becoming lower than the predetermined tracking performance. Therefore, in the second embodiment, when the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, the EGR control valve opening proportional gain is increased. The EGR control valve opening proportional gain is multiplied by the third correction value. Thus, if the EGR control valve opening proportional gain is increased, the set target EGR control valve change amount becomes large, and therefore, the target EGR control valve operation amount calculated based on the target EGR control valve change amount becomes smaller. growing. For this reason, it can suppress that target EGR rate followability becomes lower than predetermined followability. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

According to the correction of the EGR control valve opening proportional gain using the third correction value described above, the response of the EGR control valve becomes faster. Increases speed. Also from this, the change speed of the actual supercharging pressure becomes faster and approaches the expected speed. Thus, at an earlier stage, so that the actual boost pressure is controlled with a predetermined follow-up property to the target supercharging pressure.

Thus, according to the second embodiment, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, and therefore the vane response is also the response of the EGR control valve. Even when the response is slower than the intended response, the actual supercharging pressure can be controlled to the target supercharging pressure with a predetermined followability, and the actual EGR rate can be controlled to the target EGR rate with a predetermined followability. Alternatively, the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively.

Note that the third correction value used for correcting the vane opening proportional gain and the EGR control valve opening proportional gain is set based on the same concept as that for setting the third correction value in the first embodiment. The

In the second embodiment, the vane opening proportional gain and the EGR control valve opening proportional gain are corrected based on the deviation of the boost pressure deviation integrated value with respect to the reference value and the deviation of the EGR rate deviation integrated value with respect to the reference value. The Therefore, in the second embodiment, the target vane opening change amount and the target EGR control valve opening change so that the supercharging pressure deviation integrated value matches the reference value and the EGR rate deviation integrated value matches the reference value. It can be said that it corrects the amount.

In the second embodiment, the vane opening proportional gain and the EGR control valve opening proportional gain are corrected based on the supercharging pressure deviation integrated value and the EGR rate deviation integrated value, but the vane opening proportional gain is corrected. Instead of or in addition to the above, the integral gain, differential gain, or integral gain and differential gain of the above equation 3 may be corrected, and instead of or in addition to the correction of the EGR control valve opening proportional gain. The integral gain or differential gain of the above equation 4 or the integral gain and the differential gain may be corrected.

In addition, the first correction value to the third correction value in the second embodiment are not necessarily the same values as the first correction value to the third correction value in the first embodiment, respectively.

In the second embodiment, in the internal combustion engine including the supercharging pressure for controlling the supercharging pressure and the EGR device for controlling the EGR rate, the supercharging pressure and the EGR rate are changed to the target supercharging pressure and the target EGR rate. This embodiment is an embodiment to which the present invention is applied in order to control with a predetermined followability or when the supercharging pressure and the EGR rate are controlled with good balance with respect to the target supercharging pressure and the target EGR rate. However, the idea of the present invention described in relation to the first embodiment is that, in an internal combustion engine provided with a control object that controls two control amounts that affect each other, these two control amounts are set as target control amounts, respectively. The present invention can also be applied to control with a predetermined followability, or to control these two control amounts in a balanced manner with respect to the target control amount.

In view of the above, the control device for an internal combustion engine of the present invention described in relation to the second embodiment has a first control amount (for example, a second control amount) that is one of two control amounts that influence each other. The first control target (for example, the vane of the second embodiment) that controls the supercharging pressure of the embodiment and the second control amount (for example, the first control amount that is the remaining one of the two control amounts that affect each other). In a control device for an internal combustion engine that includes a second control target (for example, an EGR control valve according to the second embodiment) that controls the EGR rate of the second embodiment, the target first control amount is a target first control amount. Set as the amount (for example, the target boost pressure of the second embodiment) and the second control amount to be targeted is set as the target second control amount (for example, the target EGR rate of the second embodiment), and the first The control amount is made to reach the target first control amount, and the second control amount is set to the target second. The operation state (for example, the vane opening degree of the second embodiment) of the first control object to be targeted in order to reach the control amount is set as the target first operation state (for example, the target vane opening degree of the second embodiment). The operation state (for example, the EGR control valve opening degree of the second embodiment) to be set and set as the target is set as the target second operation state (for example, the target EGR control valve opening degree of the second embodiment). The second control is performed so that the operation state of the first control object is controlled so that the operation state of the first control object becomes the target first operation state and the operation state of the second control object becomes the target second operation state. A control device that controls a first control amount to a target first control amount by controlling an operation state of a control target, and controls a second control amount to a target second control amount. Deviation of actual first controlled variable from controlled variable Is calculated as the first control amount deviation integrated value (for example, the boost pressure deviation integrated value of the second embodiment), and the integrated value of the actual second control amount deviation with respect to the target second control amount is calculated as the second integrated value. A control device that calculates the control amount deviation integrated value and corrects the target first operation state and the target second operation state based on the first control amount deviation integrated value and the second control amount deviation integrated value. I can say that.

Also, for the same reason as described in relation to the first embodiment, according to the second embodiment, the emission discharged from the internal combustion engine is reliably maintained at a low level.

In the second embodiment, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, the response of the EGR control valve is an intended response and the target Although the EGR rate followability is higher than the predetermined followability, the response of the EGR control valve is delayed by reducing the EGR control valve opening proportional gain. According to this, even if temporarily, the target EGR rate followability may be lower than the predetermined followability. However, the reason why the response of the EGR control valve is delayed in this way is determined that it is appropriate to delay the response of the EGR control valve in order to improve the target boost pressure tracking performance to a predetermined tracking performance. Because it was done. In other words, it can be said that priority was given to improving the target boost pressure followability rather than maintaining the target EGR rate followability high. That is, according to the second embodiment, it can be said that it is possible to determine which of the target boost pressure followability and the target EGR rate followability is prioritized.

Next, an example of a routine for setting the target vane operation amount and the target EGR control valve operation amount according to the second embodiment will be described. This routine is shown in FIG. 7, and is executed at predetermined time intervals. Note that steps 20 to 25 in FIG. 7 are the same as steps 10 to 15 in FIG. 4, respectively, and thus description of these steps is omitted.

In the routine of FIG. 7, when the routine proceeds from step 25 to step 26, the above equation 3 is obtained using the boost pressure deviation ΔPim calculated in step 23 and the boost pressure deviation integrated value ΣΔPim calculated in step 24. The target vane opening change amount TDv is calculated from the above equation 4, and the target EGR control valve is calculated from the above equation 4 using the EGR rate deviation ΔRegr calculated in step 23 and the EGR rate deviation integrated value ΣΔRegr calculated in step 24. An opening change amount TDegr is calculated. Next, in step 27, the target vane opening amount TDv calculated in step 26 is multiplied by a constant conversion coefficient to calculate the target vane operation amount Mv, and the target EGR control valve calculated in step 26 is calculated. The target EGR control valve operation amount Megr is calculated by multiplying the opening change amount TDegr by a constant conversion coefficient, and the routine ends.

As an example of a routine for executing the correction of the vane opening proportional gain and the EGR control valve opening proportional gain according to the second embodiment, step 102, step 103, step 105 of the routine of FIGS. The routine which modified step 106, step 108, and step 109 as follows can be mentioned.

That is, when the routines of FIGS. 5 and 6 are used as routines for correcting the vane opening proportional gain and the EGR control valve opening proportional gain according to the second embodiment, in step 102, the current vane is calculated. The opening proportional gain GPp (k) and the current EGR control valve opening proportional gain GEp (k) are acquired. In step 103, a value (GPp (k) + K1) obtained by adding the first correction value K1 to the current vane opening proportional gain GPp (k) acquired in step 102 is a new vane opening proportional. A value obtained by subtracting the first correction value K1 from the current EGR control valve opening proportional gain GEp (k) acquired in step 102 and being set to the gain GPp (k + 1) (GEp (k) −K1) ) Is set to a new EGR control valve opening proportional gain GEp (k + 1), and the routine ends. In this case, in step 26 of FIG. 7, the target vane opening change amount TDv is calculated from the above equation 3 using the new vane opening proportional gain GPp (k + 1) set in step 103, and Using the new EGR control valve opening proportional gain GEp (k + 1) set in step 103, the target EGR control valve opening change amount TDegr is calculated from the above equation 4.

In step 105, the current vane opening proportional gain GPp (k) and the current EGR control valve opening proportional gain GEp (k) are acquired. In step 106, a value (GPp (k) × K2) obtained by multiplying the current vane opening proportional gain GPp (k) acquired in step 105 by the second correction value K2 is a new vane opening. The proportional gain GPp (k + 1) is set, and the current EGR control valve opening proportional gain GEp (k) acquired in step 105 is multiplied by the second correction value K2 to obtain a value (GEp (k) × K2). Is set to a new EGR control valve opening proportional gain GEp (k + 1), and the routine ends. In this case, in step 26 of FIG. 7, the target vane opening change amount TDv is calculated from the above equation 3 using the new vane opening proportional gain GPp (k + 1) set in step 106, and Using the new EGR control valve opening proportional gain GEp (k + 1) set in step 106, the target EGR control valve opening change amount TDegr is calculated from the above equation 4.

In step 108, the current vane opening proportional gain GPp (k) and the current EGR control valve opening proportional gain GEp (k) are acquired. In step 109, a value (GPp (k) × K2) obtained by multiplying the current vane opening proportional gain GPp (k) acquired in step 108 by the third correction value K3 is a new vane opening. A value obtained by multiplying the current EGR control valve opening proportional gain GEp (k) acquired in step 108 by the third correction value K3 is set to the proportional gain GPp (k + 1) (GEp (k) × K3) is set to a new EGR control valve opening proportional gain GEp (k + 1), and the routine ends. In this case, in step 26 of FIG. 7, the target vane opening change amount TDv is calculated from the above equation 3 using the new vane opening proportional gain GPp (k + 1) set in step 109, and Using the new EGR control valve opening proportional gain GEp (k + 1) set in step 109, the target EGR control valve opening change amount TDegr is calculated from the above equation 4.

Next, a third embodiment of the present invention will be described. As described above, in the first embodiment, the supercharging pressure deviation integrated value and its reference value are compared regardless of the engine operating state, and the EGR rate deviation integrated value and its reference value are compared. Based on the result, it is determined whether or not to correct the vane operation amount proportional gain or whether to correct the EGR control valve operation amount proportional gain. On the other hand, when the accelerator pedal opening increases and the engine operating state becomes the acceleration operating state, the target boost pressure and the target EGR rate are greatly changed. Therefore, the boost pressure deviation integrated value is also the EGR rate deviation integrated value. Also grows. Therefore, when the response of the vane is slower than the intended response or when the EGR control valve is slower than the intended response, the supercharging pressure deviation integrated value deviation from the reference value or the EGR rate deviation from the reference value The deviation of the integrated value increases. Therefore, when the supercharging pressure deviation integrated value is compared with the reference value or when the EGR rate deviation integrated value is compared with the reference value, the response of the vane is based on the result of the comparison. It is possible to accurately determine that the response is slower than the response or that the response of the EGR control valve is slower than the intended response. Therefore, in the third embodiment, the actual boost pressure and the actual EGR rate are controlled as follows.

That is, in the third embodiment, the engine speed and the engine load are stored during engine operation, and the acceleration state of the engine operation state is grasped based on the stored engine speed and engine load. Here, when it is determined that the acceleration state of the engine operation state is the predetermined acceleration state, the supercharging pressure deviation integrated value and the reference value thereof are compared and the EGR rate deviation as in the first embodiment. The integrated value is compared with its reference value.

Then, according to the comparison result, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected in the same manner as in the first embodiment. Of course, in this case, as in the first embodiment, neither the vane operation amount proportional gain nor the EGR control valve operation amount proportional gain may be corrected.

Of course, in the third embodiment, when it is determined that the acceleration state in the engine operating state is the predetermined acceleration state, the boost pressure deviation integrated value and the reference value thereof are compared as in the second embodiment. At the same time, the EGR rate deviation integrated value is compared with the reference value, and the vane opening proportional gain and the EGR control valve opening proportional gain are corrected according to the comparison result, as in the second embodiment. Also good. Of course, in this case as well, as in the second embodiment, neither the vane opening proportional gain nor the EGR control valve opening proportional gain may be corrected.

As a routine for executing the setting of the target vane operation amount and the target EGR control valve operation amount according to the third embodiment, for example, the same routine as that shown in FIG. Further, examples of routines for correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to the third embodiment include the routines of FIGS. 8 and 9.

Next, the routines of FIGS. 8 and 9 will be described. This routine is executed at predetermined time intervals.

When the routines of FIGS. 8 and 9 are started, first, the current engine speed N and the current engine load L are acquired in step 200A of FIG. Next, at step 200B, the current engine speed N and the current engine load L acquired at step 200A are stored. Next, at step 200C, the current engine speed N, the current engine load L acquired at step 200A, and the engine speed N stored at step 200B of this routine prior to the execution of this routine. Based on the engine load L, it is determined whether or not the engine operation state up to the present is a predetermined acceleration operation state. Here, when it is determined that the engine operating state up to now has been in a predetermined acceleration state, the routine proceeds to step 200. On the other hand, when it is determined that the engine operating state up to the present is not in the predetermined acceleration state, the routine ends as it is. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the current vane operation amount proportional gain GPp (k), and the current EGR control valve operation amount is proportional. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the gain GEp (k).

Note that steps 200 to 209 in FIGS. 8 and 9 are the same as steps 100 to 109 in FIGS. 5 and 6, respectively, and thus description of these steps is omitted.

Next, a fourth embodiment of the present invention will be described. As described above, in the first embodiment, the supercharging pressure deviation integrated value and the EGR rate deviation integrated value that can be taken when the response of the vane is the highest and the response of the EGR control valve is the highest are obtained in advance by experiments or the like. The obtained values are used as a reference value for the integrated value of supercharging pressure deviation and a reference value for the integrated value of EGR rate deviation. However, as the reference value of the supercharging pressure deviation integrated value and the reference value of the EGR rate deviation integrated value, the supercharging pressure deviation integrated value and EGR that can be taken when the response of the vane is relatively high and the response of the EGR control valve is relatively high. It may be preferable to adopt the rate deviation integrated value.

Therefore, in the fourth embodiment, the supercharging pressure deviation that can be taken when the response of the vane is the highest and the response of the EGR control valve is the highest as the reference value of the supercharging pressure deviation integrated value and the reference value of the EGR rate deviation integrated value. Instead of the integrated value and the EGR rate deviation integrated value, a supercharging pressure deviation integrated value and an EGR rate deviation integrated value that can be taken when the response of the vane is relatively high and the response of the EGR control valve is relatively high are adopted. In this case, the actual supercharging pressure and the actual EGR rate are controlled as follows.

That is, in the fourth embodiment, the boost pressure deviation integrated value calculated during engine operation is compared with the reference value, and the EGR rate deviation integrated value calculated during engine operation is compared with the reference value. The

Here, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, a predetermined value (hereinafter referred to as this value) is set so that the vane operation amount proportional gain is increased. (The first correction value) is added to the vane operation amount proportional gain so that the gain is corrected and the EGR control valve operation amount is reduced so that the EGR control valve operation amount proportional gain becomes small. By subtracting from the proportional gain, the gain is corrected.

Further, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, a predetermined value larger than 1 is set so that the EGR control valve operation amount proportional gain becomes large. By multiplying the value (hereinafter referred to as “second correction value”) by the EGR control valve operation amount proportional gain, the second correction value is adjusted so that the gain is corrected and the vane operation amount proportional gain is increased. The gain is corrected by multiplying the vane manipulated variable proportional gain.

Further, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to (or equal to) the reference value, the vane operation amount proportional gain is increased. By multiplying the vane operation amount proportional gain by a predetermined value (hereinafter referred to as “third correction value”), the gain is corrected and the EGR control valve operation amount proportional gain is increased. The gain is corrected by multiplying the correction value by the EGR control valve operation amount proportional gain.

Further, when the boost pressure deviation integrated value is substantially equal to (or equal to) the reference value and the EGR rate deviation integrated value is smaller than the reference value, the vane operation amount proportional gain is increased. A predetermined value (hereinafter referred to as a “fourth correction value”) is added to the vane manipulated variable proportional gain, so that the gain is corrected and the EGR control valve manipulated variable proportional gain is decreased. The gain is corrected by subtracting the correction value from the EGR control valve operation amount proportional gain.

Further, when the supercharging pressure deviation integrated value is substantially equal to (or equal to) the reference value and the EGR rate deviation integrated value is larger than the reference value, the vane operation amount proportional gain is decreased. A predetermined value (hereinafter referred to as “fifth correction value”) is subtracted from the vane manipulated variable proportional gain, thereby correcting the gain and increasing the EGR control valve manipulated variable proportional gain. The gain is corrected by adding the correction value to the EGR control valve operation amount proportional gain.

Further, when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is smaller than the reference value, a predetermined value (less than 1) is set so that the vane operation amount proportional gain becomes small. This value is hereinafter referred to as a “sixth correction value” and multiplied by the vane operation amount proportional gain so that the gain is corrected and the sixth correction value is EGR controlled so that the EGR control valve operation amount proportional gain becomes small. The gain is corrected by multiplying the valve operation amount proportional gain.

Further, when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is larger than the reference value, a predetermined value (hereinafter referred to as this value) is set so that the vane operation amount proportional gain becomes small. The seventh correction value is proportional to the EGR control valve operation amount so that the gain is corrected by subtracting the "seventh correction value" from the vane operation amount proportional gain and the EGR control valve operation amount proportional gain is increased. The gain is corrected by being added to the gain.

Further, when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is substantially equal to (or equal to) the reference value, the vane operation amount proportional gain is reduced. The gain is corrected by multiplying the vane manipulated variable proportional gain by a predetermined value smaller than 1 (hereinafter referred to as “eighth correction value”), and the EGR control valve manipulated variable proportional gain is reduced. Thus, the gain is corrected by multiplying the EGR control valve operation amount proportional gain by the eighth correction value.

Further, when the relationship between the supercharging pressure deviation integrated value with respect to the reference value and the relationship between the EGR rate deviation integrated value with respect to the reference value is other than the relationship mentioned above, the vane operation amount proportional gain is also proportional to the EGR control valve operation amount. Gain is not corrected.

As described above, when the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected, and these corrected gains are used for setting the target vane operation amount and the target EGR control valve operation amount, respectively, The effect that the supply pressure can be controlled to the target boost pressure with a predetermined followability and the EGR rate can be controlled to the target EGR rate with the predetermined followability, or the actual boost pressure and the actual EGR The rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively.

That is, as described in relation to the first embodiment, the supercharging pressure and the EGR rate are control amounts that influence each other. Accordingly, when the supercharging pressure is controlled by the supercharger 35, the supercharging pressure by the supercharger 35 with respect to the supercharging pressure when the supercharging pressure is to be controlled with the target supercharging pressure with a predetermined followability. Considering the influence of the control of the EGR rate by the EGR device 50 on the supercharging pressure as well as the influence of the control of the supercharging pressure is advantageous from the viewpoint of controlling the supercharging pressure to the target supercharging pressure with higher accuracy. There is. Further, when the EGR rate is controlled by the EGR device 50, the control of the EGR rate by the EGR device 50 with respect to the EGR rate is taken into account when the EGR rate is controlled with a predetermined followability to the target EGR rate. In addition, considering the effect of supercharging pressure control by the supercharger 35 on the EGR rate is advantageous from the viewpoint of controlling the EGR rate to the target EGR rate with higher accuracy.

At this time, in the fourth embodiment, the first correction value is added to the vane operation amount proportional gain so that the vane operation amount proportional gain is increased, and the EGR control valve operation amount proportional gain is decreased. The first correction value is subtracted from the manipulated variable proportional gain. According to this, for the same reason as described in relation to the first embodiment, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure, and the actual EGR rate is predetermined to the target EGR rate. It is controlled with the following ability.

It should be noted that the first correction value used for correcting the proportional gain is set based on the same concept as that for setting the first correction value in the first embodiment.

At this time, in the fourth embodiment, the second correction value is multiplied by the vane operation amount proportional gain so that the vane operation amount proportional gain is increased, and the EGR control valve operation amount proportional gain is increased. The operation amount proportional gain is multiplied by the second correction value. According to this, for the same reason as described in relation to the first embodiment, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure, and the actual EGR rate is predetermined to the target EGR rate. It is controlled with the following ability.

It should be noted that the second correction value used for correcting the proportional gain is set based on the same concept as that for setting the second correction value in the first embodiment.

Further, as described in connection with the first embodiment, when the response of the vane is slower than the intended response and the response of the EGR control valve is also slower than the intended response, the boost pressure deviation integration is performed. The value is larger than the reference value, and the EGR rate deviation integrated value becomes substantially equal to the reference value (or, in some cases, becomes equal to the reference value).

At this time, in the fourth embodiment, the third correction value is multiplied by the vane operation amount proportional gain so that the vane operation amount proportional gain is increased, and the EGR control valve operation amount proportional gain is increased. The operation amount proportional gain is multiplied by the third correction value. According to this, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure and the actual EGR rate is predetermined to the target EGR rate from the same reason as described in relation to the first embodiment. It is controlled with the following ability.

It should be noted that the third correction value used for correcting the proportional gain is set based on the same concept as that for setting the third correction value in the first embodiment.

Further, when the response of the vane is slower than the intended response and the response of the EGR control valve is faster than the intended response, the boost pressure deviation integrated value is substantially equal to the reference value (or the reference value). The EGR rate deviation integrated value becomes smaller than the reference value. Next, this will be described.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the exhaust pressure increases due to the decrease in the vane opening and the exhaust pressure due to the decrease in the EGR control valve opening. As a result, the boost pressure is increased. Here, when the response of the vane is slower than the intended response, the exhaust pressure increase rate due to the decrease in the vane opening becomes slower than the intended rate. On the other hand, when the response of the EGR control valve is faster than the intended response, the exhaust pressure increase rate due to the decrease in the EGR control valve opening becomes faster than the intended rate. For this reason, the decrease in the exhaust pressure increase rate due to the decrease in the vane opening and the increase in the exhaust pressure increase rate due to the decrease in the EGR control valve opening cancel each other. As a result, as a whole, The increase speed of the supercharging pressure is substantially the expected speed, and in some cases, the expected speed. Therefore, when the actual boost pressure is to be increased when the response of the vane is slower than the expected response and the response of the EGR control valve is faster than the expected response, the boost pressure deviation integrated value Is approximately equal to the reference value (or, in some cases, is equal to the reference value).

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the EGR gas amount increases due to the decrease in the vane opening and the EGR gas due to the decrease in the EGR control valve opening. A decrease in volume occurs at the same time. Here, when the response of the vane is slower than the intended response, the increasing rate of the EGR gas amount due to the decrease in the vane opening becomes slower than the intended rate. On the other hand, when the response of the EGR control valve is faster than the intended response, the rate of decrease in the EGR gas amount due to the decrease in the EGR control valve opening becomes faster than the intended rate. For this reason, as a whole, the rate of decrease of the EGR gas amount becomes faster than the intended rate. Therefore, if the actual EGR rate is to be reduced when the vane response is slower than the intended response and the EGR control valve response is faster than the intended response, the integrated EGR rate deviation value is It becomes smaller than the reference value.

Also, when the target supercharging pressure is lowered, the target EGR rate is raised. Therefore, at this time, the vane opening is increased in order to decrease the actual supercharging pressure toward the target supercharging pressure, and at the same time, the EGR control valve opening is increased in order to increase the actual EGR rate toward the target EGR rate. Is increased.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the exhaust pressure decreases due to the increase in the vane opening and the exhaust pressure due to the increase in the EGR control valve opening. As a result, the supercharging pressure is reduced. Here, when the response of the vane is slower than the intended response, the exhaust pressure decrease rate due to the increase in the vane opening becomes slower than the intended rate. On the other hand, when the response of the EGR control valve is faster than the intended response, the exhaust pressure decreasing rate due to the increase in the EGR control valve opening becomes faster than the intended rate. For this reason, the decrease in the exhaust pressure decrease rate due to the increase in the vane opening and the increase in the exhaust pressure decrease rate due to the increase in the EGR control valve opening cancel each other. As a result, as a whole, The decreasing speed of the supercharging pressure is substantially the expected speed, and in some cases, the expected speed. Therefore, when the actual supercharging pressure is to be reduced when the response of the vane is slower than the intended response and the response of the EGR control valve is faster than the intended response, the supercharging pressure deviation integrated value Is approximately equal to the reference value (or, in some cases, is equal to the reference value).

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the EGR gas is decreased due to the increase in the vane opening and the EGR gas is increased due to the increase in the EGR control valve opening. An increase in quantity occurs simultaneously. Here, when the response of the vane is slower than the intended response, the rate of decrease in the EGR gas amount due to the increase in the vane opening becomes slower than the intended rate. On the other hand, when the response of the EGR control valve is faster than the intended response, the increasing speed of the EGR gas amount due to the increase in the EGR control valve opening degree becomes faster than the intended speed. For this reason, as a whole, the increasing rate of the EGR gas amount becomes faster than the intended rate. Therefore, the EGR rate deviation integrated value is also obtained when the actual EGR rate is increased when the response of the vane is slower than the intended response and the response of the EGR control valve is faster than the intended response. Becomes smaller than the reference value.

Thus, when the response of the vane is slower than the intended response and the response of the EGR control valve is faster than the intended response, the boost pressure deviation integrated value is substantially equal to the reference value (or The EGR rate deviation integrated value becomes smaller than the reference value).

Here, if the operation amount of the EGR control valve is reduced, the response of the EGR control valve is delayed. Therefore, when the supercharging pressure deviation integrated value is substantially equal to (or equal to) the reference value and the EGR rate deviation integrated value is smaller than the reference value, the EGR control valve operation amount is reduced. As a result, the response of the EGR control valve becomes slow, and as a result, the rate of change of the actual EGR rate approaches the intended rate. Therefore, in the fourth embodiment, in this case, the fourth correction value is subtracted from the EGR control valve operation amount proportional gain so that the EGR control valve operation amount proportional gain becomes smaller. Thus, if the EGR control valve operation amount proportional gain is decreased, the set target EGR control valve operation amount is decreased. According to this, the response of the EGR control valve becomes slow, and as a result, the change speed of the actual EGR rate becomes slow and approaches the intended speed. Then, if the correction of the EGR control valve operation amount proportional gain is repeated, the actual EGR rate change speed finally reaches the intended speed. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

On the other hand, when the supercharging pressure deviation integrated value is approximately equal to (or equal to) the reference value and the EGR rate deviation integrated value is smaller than the reference value, the actual supercharging pressure has a predetermined followability. It can be seen that the target boost pressure is controlled. However, as described above, in this case, since the EGR control valve operation amount proportional gain is reduced and the response of the EGR control valve is delayed, the rate of change of the exhaust pressure due to the change of the EGR control valve becomes slow. In this case, the target supercharging pressure followability becomes lower than the predetermined followability. On the other hand, if the vane operation amount is increased, the response of the vanes becomes faster, so that it is possible to suppress the target boost pressure followability from becoming lower than the predetermined followability. Therefore, in the fourth embodiment, when the boost pressure deviation integrated value is substantially equal to (or equal to) the reference value, and the EGR rate deviation integrated value is smaller than the reference value, the vane operation amount The fourth correction value is added to the vane operation amount proportional gain so as to increase the proportional gain. Thus, if the vane operation amount proportional gain is increased, the set target vane operation amount is increased. For this reason, it can suppress that target supercharging pressure followability becomes lower than predetermined followability. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

Thus, according to the fourth embodiment, the supercharging pressure deviation integrated value is substantially equal to (or equal to) the reference value, and the EGR rate deviation integrated value is smaller than the reference value. Even when the response of the vane is slower than the predetermined response and the response of the EGR control valve is faster than the predetermined response, the actual supercharging pressure can be controlled to the target supercharging pressure with a predetermined follow-up performance. The EGR rate can be controlled with a predetermined followability to the target EGR rate, or the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively. It can be done.

The fourth correction value used for correcting the proportional gain is that the boost pressure deviation integrated value is substantially equal to (or equal to) the reference value, and the EGR rate deviation integrated value is the reference value. Is set to a value that allows the target boost pressure followability to reach the predetermined followability as early as possible and does not lower the target EGR rate followability below the predetermined followability.

Further, in the correction of the proportional gain using the fourth correction value, the boost pressure deviation integrated value is substantially equal to (or equal to) the reference value, and the EGR rate deviation integrated value is smaller than the reference value. In other words, the response of the vane is slower than the predetermined response and the response of the EGR control valve is faster than the predetermined response. In other words, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected without considering how much the vane response and the EGR control valve response deviate from the predetermined responses. Accordingly, the fourth correction value is obtained by correcting the target boost pressure follow-up significantly beyond the predetermined follow-up by the correction of the one-time vane operation amount proportional gain and the EGR control valve operation amount proportional gain, and the target EGR rate follow-up. It is considered that it is preferable to set the value to such a small value that the performance does not greatly exceed the predetermined followability.

In the fourth embodiment, correction of the proportional gain is performed from the viewpoint of simplifying the correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain and correcting the proportional gain in a well-balanced manner. The same fourth correction value is used as the correction value. However, if necessary, the correction values for correcting each proportional gain may be different from each other.

In the fourth embodiment, the gain is corrected by adding the fourth correction value to the vane operation amount proportional gain. However, if necessary, a specific value larger than 1 is set to a vane operation amount proportional gain. The gain may be corrected by multiplying by. In the fourth embodiment, the fourth correction value is corrected by subtracting the fourth correction value from the EGR control valve operation amount proportional gain. However, if necessary, a specific value smaller than 1 is set to an EGR control valve. The gain may be corrected by multiplying the manipulated variable proportional gain. In this case, in terms of correcting these proportional gains in a well-balanced manner, the specific values multiplied by these proportional gains are set so that the sum of the specific values becomes a constant value, or It is considered preferable that the ratio of specific values is set to be a constant value.

In addition, when the response of the vane is faster than the intended response and the response of the EGR control valve is slower than the intended response, the boost pressure deviation integrated value is substantially equal to the reference value (or the reference value). The EGR rate deviation integrated value becomes larger than the reference value. Next, this will be described.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the exhaust pressure increases due to the decrease in the vane opening and the exhaust pressure due to the decrease in the EGR control valve opening. As a result, the boost pressure is increased. Here, when the response of the vane is faster than the intended response, the exhaust pressure increase rate due to the decrease in the vane opening becomes faster than the intended rate. On the other hand, when the response of the EGR control valve is slower than the intended response, the exhaust pressure increase rate due to the decrease in the EGR control valve opening becomes slower than the intended rate. For this reason, the increase in the exhaust pressure increase rate due to the decrease in the vane opening and the decrease in the exhaust pressure increase rate due to the decrease in the EGR control valve opening cancel each other. As a result, as a whole, The increase speed of the supercharging pressure is substantially the expected speed, and in some cases, the expected speed. Therefore, when an attempt is made to increase the actual boost pressure when the response of the vane is faster than the expected response and the response of the EGR control valve is slower than the expected response, the supercharging pressure deviation integrated value Is approximately equal to the reference value (or, in some cases, is equal to the reference value).

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the EGR gas increases due to the decrease in the vane opening and the EGR gas due to the decrease in the EGR control valve opening. A decrease in volume occurs at the same time. Here, when the response of the vane is faster than the intended response, the increasing speed of the EGR gas amount due to the decrease in the vane opening becomes faster than the intended speed. On the other hand, when the response of the EGR control valve is slower than the intended response, the rate of decrease in the EGR gas amount due to the decrease in the EGR control valve opening becomes slower than the intended rate. For this reason, as a whole, the rate of decrease in the amount of EGR gas becomes slower than the intended rate. Accordingly, when the actual EGR rate is to be reduced when the vane response is faster than the intended response and the EGR control valve response is slower than the intended response, the EGR rate deviation integrated value is less than the reference value. Also grows.

Also, when the target supercharging pressure is lowered, the target EGR rate is raised. Accordingly, at this time, the vane opening is increased in order to decrease the actual supercharging pressure toward the target supercharging pressure, and at the same time, the EGR control valve opening is increased in order to increase the actual EGR rate toward the target EGR rate. Is increased.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the exhaust pressure decreases due to the increase in the vane opening and the exhaust pressure due to the increase in the EGR control valve opening. As a result, the supercharging pressure is reduced. Here, when the response of the vane is faster than the intended response, the exhaust pressure lowering rate due to the increase in the vane opening becomes faster than the intended rate. On the other hand, when the response of the EGR control valve is slower than the intended response, the exhaust pressure decrease rate due to the increase in the EGR control valve opening becomes slower than the intended rate. For this reason, the increase in the exhaust pressure decrease rate due to the increase in the vane opening and the decrease in the exhaust pressure decrease rate due to the increase in the EGR control valve opening cancel each other. As a result, as a whole, The decreasing speed of the supercharging pressure is substantially the expected speed, and in some cases, the expected speed. Therefore, when the actual supercharging pressure is to be reduced when the response of the vane is faster than the intended response and the response of the EGR control valve is slower than the intended response, the supercharging pressure deviation integrated value Is approximately equal to the reference value (or, in some cases, is equal to the reference value).

Thus, when the response of the vane is faster than the intended response and the response of the EGR control valve is slower than the intended response, the boost pressure deviation integrated value is approximately equal to the reference value (or The EGR rate deviation integrated value becomes larger than the reference value.

Here, if the operation amount of the EGR control valve is increased, the response of the EGR control valve becomes faster. Therefore, when the supercharging pressure deviation integrated value is substantially equal to (or equal to) the reference value and the EGR rate deviation integrated value is larger than the reference value, the EGR control valve operation amount is increased. As a result, the response of the EGR control valve becomes faster, and as a result, the change rate of the actual EGR rate approaches the intended speed. Therefore, in the fourth embodiment, in this case, the fifth correction value is added to the EGR control valve operation amount proportional gain so that the EGR control valve operation amount proportional gain is increased. Thus, if the EGR control valve operation amount proportional gain is increased, the set target EGR control valve operation amount is increased. According to this, the response of the EGR control valve becomes faster, and as a result, the change speed of the actual EGR rate becomes faster and approaches the intended speed. Then, if the correction of the EGR control valve operation amount proportional gain is repeated, the actual EGR rate change speed finally reaches the intended speed. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

On the other hand, when the supercharging pressure deviation integrated value is substantially equal to (or equal to) the reference value and the EGR rate deviation integrated value is larger than the reference value, the actual supercharging pressure has a predetermined followability. It can be seen that the target boost pressure is controlled. However, as described above, in this case, the EGR control valve operation amount proportional gain is increased, and the response of the EGR control valve is increased, so that the exhaust pressure change rate due to the change of the EGR control valve is increased. In this case, the target boost pressure followability is higher than the predetermined followability. On the other hand, if the vane operation amount is reduced, the response of the vane is delayed, so that the target boost pressure followability can be suppressed from becoming higher than the predetermined followability. Therefore, in the fourth embodiment, when the supercharging pressure deviation integrated value is substantially equal to (or equal to) the reference value and the EGR rate deviation integrated value is larger than the reference value, the vane operation amount The fifth correction value is subtracted from the vane operation amount proportional gain so that the proportional gain becomes smaller. Thus, if the vane operation amount proportional gain is reduced, the set target vane operation amount is reduced. For this reason, it can suppress that target supercharging pressure followability becomes higher than predetermined followability. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

Thus, according to the fourth embodiment, the boost pressure deviation integrated value is substantially equal to (or equal to) the reference value, and the EGR rate deviation integrated value is larger than the reference value. Even when the response of the vane is faster than the predetermined response and the response of the EGR control valve is slower than the predetermined response, the actual supercharging pressure can be controlled to the target supercharging pressure with a predetermined follow-up performance. The EGR rate can be controlled with a predetermined followability to the target EGR rate, or the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively. It can be done.

The fifth correction value used for correcting the proportional gain is that the boost pressure deviation integrated value is substantially equal to (or equal to) the reference value and the EGR rate deviation integrated value is the reference value. Is set to a value that allows the target boost pressure followability to reach the predetermined followability as early as possible and does not lower the target EGR rate followability below the predetermined followability.

Further, in the correction of the proportional gain using the fifth correction value, the boost pressure deviation integrated value is substantially equal to (or equal to) the reference value, and the EGR rate deviation integrated value is larger than the reference value. In other words, the vane response is faster than the predetermined response and the EGR control valve response is slower than the predetermined response. In other words, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected without considering how much the vane response and the EGR control valve response deviate from the predetermined responses. Therefore, the fifth correction value is obtained by making the target boost pressure follow-up performance not significantly lower than the predetermined follow-up performance and correcting the target EGR rate follow-up by correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain once. It is considered that it is preferable to set the value to such a small value that the performance does not greatly exceed the predetermined followability.

In the fourth embodiment, correction of the proportional gain is performed from the viewpoint of simplifying the correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain and correcting the proportional gain in a well-balanced manner. The same fifth correction value is used as the correction value. However, if necessary, the correction values for correcting each proportional gain may be different from each other.

In the fourth embodiment, the fifth correction value is corrected by subtracting the fifth correction value from the vane operation amount proportional gain. However, if necessary, a specific value smaller than 1 is set to a vane operation amount proportional gain. The gain may be corrected by multiplying by. In the fourth embodiment, the fifth correction value is corrected by adding the fifth correction value to the EGR control valve operation amount proportional gain. However, if necessary, a specific value greater than 1 is set to an EGR control valve. The gain may be corrected by multiplying the manipulated variable proportional gain. In this case, in terms of correcting these proportional gains in a well-balanced manner, the specific values multiplied by these proportional gains are set so that the sum of the specific values becomes a constant value, or It is considered preferable that the ratio of specific values is set to be a constant value.

Further, when the response of the vane is the intended response and the response of the EGR control valve is faster than the intended speed, the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value. Becomes smaller than the reference value. Next, this will be described.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the exhaust pressure increases due to the decrease in the vane opening and the exhaust pressure due to the decrease in the EGR control valve opening. As a result, the boost pressure is increased. Here, when the response of the vane is an intended response, the exhaust pressure increasing speed resulting from the decrease in the vane opening becomes the intended speed. On the other hand, when the response of the EGR control valve is faster than the intended response, the exhaust pressure increase rate due to the decrease in the EGR control valve opening becomes faster than the intended rate. For this reason, as a whole, the increase speed of the supercharging pressure becomes faster than the intended speed. Therefore, when the actual boost pressure is to be increased when the vane response is the desired response and the EGR control valve response is faster than the expected response, the boost pressure deviation integrated value is It becomes smaller than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the EGR gas amount increases due to the decrease in the vane opening and the EGR gas due to the decrease in the EGR control valve opening. A decrease in volume occurs at the same time. Here, when the response of the vane is an intended response, the increase rate of the EGR gas amount due to the decrease in the vane opening becomes the intended rate. On the other hand, when the response of the EGR control valve is faster than the intended response, the rate of decrease in the EGR gas amount due to the decrease in the EGR control valve opening becomes faster than the intended rate. For this reason, as a whole, the rate of decrease of the EGR gas amount becomes faster than the intended rate. Therefore, when the actual EGR rate is to be reduced when the vane response is the intended response and the EGR control valve response is faster than the intended response, the EGR rate deviation integrated value is less than the reference value. Get smaller.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the exhaust pressure decreases due to the increase in the vane opening and the exhaust pressure due to the increase in the EGR control valve opening. As a result, the supercharging pressure is reduced. Here, when the response of the vane is an intended response, the exhaust pressure lowering speed resulting from the increase in the vane opening becomes the intended speed. On the other hand, when the response of the EGR control valve is faster than the intended response, the exhaust pressure decreasing rate due to the increase in the EGR control valve opening becomes faster than the intended rate. For this reason, as a whole, the reduction speed of the supercharging pressure becomes faster than the intended speed. Therefore, when the actual boost pressure is to be reduced when the vane response is the desired response and the EGR control valve response is faster than the expected response, the boost pressure deviation integrated value is It becomes smaller than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the EGR gas caused by the decrease in the EGR gas amount due to the increase in the vane opening and the increase in the EGR control valve opening. An increase in quantity occurs simultaneously. Here, when the response of the vane is an intended response, the rate of decrease in the EGR gas amount due to the increase in the vane opening becomes the intended rate. On the other hand, when the response of the EGR control valve is faster than the intended response, the increasing speed of the EGR gas amount due to the increase in the EGR control valve opening degree becomes faster than the intended speed. For this reason, as a whole, the rate of increase in the amount of EGR gas is faster than the intended rate. Accordingly, when the actual EGR rate is to be increased when the vane response is the intended response and the EGR control valve response is faster than the intended response, the EGR rate deviation integrated value is less than the reference value. Get smaller.

Thus, when the response of the vane is the intended response and the response of the EGR control valve is faster than the intended speed, the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation The integrated value becomes smaller than the reference value.

Here, if the operation amount of the EGR control valve is reduced, the response of the EGR control valve is delayed. Therefore, if the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is smaller than the reference value, the response of the EGR control valve is delayed if the EGR control valve operation amount is reduced. As a result, the deviation speed of the actual EGR rate approaches the intended speed. Therefore, in the fourth embodiment, in this case, the EGR control valve operation amount proportional gain is multiplied by the sixth correction value so that the EGR control valve operation amount proportional gain becomes smaller. Thus, if the EGR control valve operation amount proportional gain is decreased, the set target EGR control valve operation amount is decreased. According to this, the response of the EGR control valve becomes slow, and as a result, the change speed of the actual EGR rate becomes slow and approaches the intended speed. Then, if the correction of the EGR control valve operation amount proportional gain is repeated, the actual EGR rate changing speed finally reaches the intended speed. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

On the other hand, if the amount of vane operation is reduced, the response of the vane becomes slow. Therefore, when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is smaller than the reference value, if the vane operation amount is reduced, the response of the vane is delayed. The change speed of the actual supercharging pressure approaches the expected speed. Therefore, in the fourth embodiment, in this case, the vane operation amount proportional gain is multiplied by the second correction value so that the vane operation amount proportional gain becomes small. Thus, if the vane operation amount proportional gain is reduced, the set target vane operation amount is reduced. According to this, the response of the vane becomes slow, and as a result, the change speed of the actual supercharging pressure becomes slow and approaches the intended speed. If the correction of the vane operation amount gain is repeated, the change speed of the actual supercharging pressure finally reaches the intended speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

In addition, according to the correction of the EGR control valve operation amount proportional gain using the sixth correction value described above, the response of the EGR control valve becomes slow, so that the change of the exhaust pressure due to the change of the EGR control valve opening degree is reduced. The speed is slow. Also from this, the change speed of the actual supercharging pressure becomes slow and approaches the intended speed. Thus, at an earlier stage, so that the actual boost pressure is controlled with a predetermined follow-up property to the target supercharging pressure.

Thus, according to the fourth embodiment, the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is smaller than the reference value, and therefore the vane response is the desired response. Nevertheless, even when the response of the EGR control valve is faster than the intended response, the actual boost pressure can be controlled with a predetermined follow-up to the target boost pressure and the actual EGR rate can be set to the target EGR rate. The rate can be controlled with a predetermined followability, or the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively.

The sixth correction value used to correct the proportional gain is the target boost pressure when the boost pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is smaller than the reference value. The followability can be set to a value that can reach the predetermined followability as early as possible and the target EGR rate followability can reach the predetermined followability as early as possible.

Further, the correction of the proportional gain using the sixth correction value is performed when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is smaller than the reference value. This is performed with a predetermined response and that the response of the EGR control valve is faster than the predetermined response. In other words, the vane manipulated variable proportional gain and the EGR control valve manipulated variable proportional gain are corrected without considering how much the boost pressure deviation accumulated value and the EGR rate deviation accumulated value deviate from their reference values. . Accordingly, the sixth correction value does not decrease the target boost pressure follow-up performance and the target EGR rate follow-up performance greatly beyond the predetermined follow-up performance by correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain once. It is considered preferable to set a value as small as possible.

In the fourth embodiment, correction of the proportional gain is performed from the viewpoint of simplifying the correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain and correcting the proportional gain in a well-balanced manner. The same second correction value is used as the correction value. However, if necessary, the correction values for correcting each proportional gain may be different from each other.

Further, in the fourth embodiment, the gain is corrected by multiplying the vane operation amount proportional gain by the sixth correction value, but if necessary, a specific value is set so that the vane operation amount proportional gain is reduced. May be corrected from the vane manipulated variable proportional gain. In the fourth embodiment, the EGR control valve operation amount proportional gain is corrected by multiplying the sixth correction value by the EGR control valve operation amount proportional gain. However, if necessary, the EGR control valve operation amount proportional gain is reduced. Alternatively, the gain may be corrected by subtracting a specific value from the EGR control valve operation amount proportional gain. In this case, from the viewpoint of correcting these proportional gains in a well-balanced manner, it is considered preferable that specific values added to these proportional gains are set to the same value.

Further, when the response of the vane is faster than the intended response and the response of the EGR control valve is the intended response, the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is It becomes larger than the reference value. Next, this will be described.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the exhaust pressure increases due to the decrease in the vane opening and the exhaust pressure due to the decrease in the EGR control valve opening. As a result, the boost pressure is increased. Here, when the response of the vane is faster than the intended response, the exhaust pressure increase rate due to the decrease in the vane opening becomes faster than the intended rate. On the other hand, when the response of the EGR control valve is an intended response, the rising speed of the exhaust pressure due to the decrease in the EGR control valve opening becomes the intended speed. For this reason, as a whole, the increase speed of the supercharging pressure becomes faster than the intended speed. Therefore, when the actual boost pressure is to be increased when the response of the vane is faster than the expected response and the response of the EGR control valve is the expected response, the boost pressure deviation integrated value is It becomes smaller than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the EGR gas amount increases due to the decrease in the vane opening and the EGR gas due to the decrease in the EGR control valve opening. A decrease in volume occurs at the same time. Here, when the response of the vane is faster than the intended response, the increasing speed of the EGR gas amount due to the decrease in the vane opening becomes faster than the intended speed. On the other hand, when the response of the EGR control valve is an intended response, the rate of decrease of the EGR gas amount resulting from the decrease in the EGR control valve opening becomes the intended rate. For this reason, as a whole, the rate of decrease of the EGR gas amount becomes slower than the intended rate. Accordingly, when the actual EGR rate is to be reduced when the response of the vane is faster than the intended response and the response of the EGR control valve is the intended response, the EGR rate deviation integrated value is less than the reference value. growing.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the exhaust pressure decreases due to the increase in the vane opening and the exhaust pressure due to the increase in the EGR control valve opening. As a result, the supercharging pressure is reduced. Here, when the response of the vane is faster than the intended response, the exhaust pressure decrease rate due to the increase in the vane opening becomes faster than the intended rate. On the other hand, when the response of the EGR control valve is the intended response, the exhaust pressure decrease rate due to the increase in the EGR control valve opening becomes the intended rate. For this reason, as a whole, the reduction speed of the supercharging pressure becomes faster than the intended speed. Therefore, when the actual boost pressure is to be increased when the response of the vane is faster than the expected response and the response of the EGR control valve is the expected response, the boost pressure deviation integrated value is It becomes smaller than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the EGR gas caused by the decrease in the EGR gas amount due to the increase in the vane opening and the increase in the EGR control valve opening. An increase in quantity occurs simultaneously. Here, when the response of the vane is faster than the intended response, the rate of decrease of the EGR gas amount due to the increase in the vane opening becomes faster than the intended rate. On the other hand, when the response of the EGR control valve is a desired response, the increasing speed of the EGR gas amount resulting from the increase in the EGR control valve opening becomes the intended speed. For this reason, as a whole, the increase rate of the EGR gas amount becomes slower than the intended rate. Accordingly, when the actual EGR rate is to be reduced when the response of the vane is faster than the intended response and the response of the EGR control valve is the intended response, the EGR rate deviation integrated value is less than the reference value. growing.

Here, if the amount of vane operation is reduced, the response of the vane becomes slow. Therefore, when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is larger than the reference value, if the vane operation amount is reduced, the response of the vane is delayed. The change speed of the actual supercharging pressure approaches the intended speed. Therefore, in the fourth embodiment, in this case, the seventh correction value is subtracted from the vane operation amount proportional gain so that the vane operation amount proportional gain becomes smaller. Thus, if the vane operation amount proportional gain is reduced, the set target vane operation amount is reduced. According to this, the response of the vane becomes slow, and as a result, the change speed of the actual supercharging pressure becomes slow and approaches the intended speed. If the correction of the vane operation amount proportional gain is repeated, finally, the change speed of the actual supercharging pressure reaches the intended speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

On the other hand, if the EGR control valve operation amount is increased, the response of the EGR control valve becomes faster. Therefore, when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is larger than the reference value, if the EGR control valve operation amount is increased, the response of the EGR control valve becomes faster. As a result, the actual EGR rate change speed approaches the intended speed. Therefore, in the fourth embodiment, in this case, the seventh correction value is added to the EGR control valve operation amount proportional gain so that the EGR control valve operation amount proportional gain is increased. Thus, if the EGR control valve operation amount proportional gain is increased, the set target EGR control valve operation amount is increased. According to this, the response of the EGR control valve becomes faster, and as a result, the change speed of the actual EGR rate becomes faster and approaches the intended speed. Then, if the correction of the EGR control valve operation amount proportional gain is repeated, the actual EGR rate changing speed finally reaches the intended speed. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

In addition, according to the correction | amendment of the vane operation amount proportional gain using the 7th correction value mentioned above, since the response of a vane becomes slow, the speed of the change of the EGR gas amount resulting from the change of a vane opening degree becomes slow. Also from this, the rate of change of the actual EGR rate increases and approaches the expected rate. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate earlier.

Thus, according to the fourth embodiment, the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is larger than the reference value. Therefore, the response of the EGR control valve is expected. Even when the response of the vane is faster than the intended response, the actual supercharging pressure can be controlled to the target supercharging pressure with a predetermined followability, and the actual EGR rate can be set to the target EGR. The rate can be controlled with a predetermined followability, or the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively.

The seventh correction value used for correcting the proportional gain is the target boost pressure when the boost pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is larger than the reference value. The followability can be set to a value that can reach the predetermined followability as early as possible and that the target EGR rate followability is not lower than the predetermined followability.

Further, the correction of the proportional gain using the seventh correction value is performed when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is larger than the reference value. It is performed that the response of the EGR control valve is the intended response faster than the intended response. In other words, the vane manipulated variable proportional gain and the EGR control valve manipulated variable proportional gain are corrected without considering how much the boost pressure deviation accumulated value and the EGR rate deviation accumulated value deviate from their reference values. . Accordingly, the seventh correction value is obtained by making the target boost pressure follow-up performance not significantly lower than the predetermined follow-up performance and the target EGR rate follow-up by correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain once. It is considered that it is preferable to set the value to such a small value that the performance does not greatly exceed the predetermined followability.

In the fourth embodiment, correction of the proportional gain is performed from the viewpoint of simplifying the correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain and correcting the proportional gain in a well-balanced manner. The same seventh correction value is used as the correction value. However, if necessary, the correction values for correcting each proportional gain may be different from each other.

Further, in the fourth embodiment, the gain is corrected by subtracting the seventh correction value from the vane operation amount proportional gain. However, if necessary, a specific value smaller than 1 is set to a vane operation amount proportional gain. The gain may be corrected by multiplying by. In the fourth embodiment, the gain is corrected by adding the seventh correction value to the EGR control valve operation amount proportional gain. However, if necessary, a specific value larger than 1 is set to an EGR control valve. The gain may be corrected by multiplying the manipulated variable proportional gain. In this case, in terms of correcting these proportional gains in a well-balanced manner, the specific values multiplied by these proportional gains are set such that the sum of the specific values becomes a constant value, or It is considered preferable that the ratio of the values is set to a constant value.

Further, when the response of the vane is faster than the intended response and the response of the EGR control valve is also faster than the intended response, the supercharging pressure deviation integrated value is smaller than the reference value (in detail, The EGR rate deviation integrated value is smaller than the supercharging pressure deviation integrated value when the response of the EGR control valve is faster than the intended response although the vane response is the expected response). Is approximately equal to the reference value (or, in some cases, is equal to the reference value). Next, this will be described.

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the exhaust pressure increases due to the decrease in the vane opening and the exhaust pressure due to the decrease in the EGR control valve opening. As a result, the boost pressure is increased. Here, when the response of the vane and the response of the EGR control valve are faster than the intended response, the exhaust pressure increase rate due to the decrease in the vane opening degree also increases the exhaust pressure due to the decrease in the EGR control valve opening degree. The speed is also faster than the intended speed. For this reason, the increasing speed of the supercharging pressure is significantly faster than the intended speed. Therefore, when the actual supercharging pressure is increased when both the vane response and the EGR control valve response are faster than the intended response, the supercharging pressure deviation integrated value becomes significantly smaller than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously reduced, the EGR gas increases due to the decrease in the vane opening and the EGR gas due to the decrease in the EGR control valve opening. A decrease in volume occurs at the same time. Here, when both the response of the vane and the response of the EGR control valve are faster than the intended response, the increase rate of the EGR gas amount due to the decrease in the vane opening is also the EGR gas amount due to the decrease in the EGR control valve opening. The rate of decrease of is also faster than the expected rate. For this reason, the increase in the increase rate of the EGR gas amount due to the decrease in the vane opening degree and the increase in the decrease rate of the EGR gas amount due to the decrease in the EGR control valve opening amount cancel each other. The rate of decrease in the EGR rate is approximately the expected rate, and in some cases, the expected rate. Therefore, if the actual EGR rate is to be reduced when both the vane response and the EGR control valve response are faster than the intended response, the EGR rate deviation integrated value becomes substantially equal to the reference value (or depending on circumstances) Is equal to its reference value).

Here, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the exhaust pressure decreases due to the increase in the vane opening and the exhaust pressure due to the increase in the EGR control valve opening. As a result, the supercharging pressure is reduced. Here, when the response of the vane and the response of the EGR control valve are faster than the intended response, the exhaust pressure decrease rate due to the increase in the vane opening degree also decreases the exhaust pressure due to the increase in the EGR control valve opening degree. The speed is also faster than the intended speed. For this reason, as a whole, the supercharging pressure decreasing rate is significantly faster than the intended rate. Therefore, when the actual supercharging pressure is to be reduced when both the vane response and the EGR control valve response are faster than the intended response, the supercharging pressure deviation integrated value is significantly smaller than the reference value.

On the other hand, as described above, when the vane opening and the EGR control valve opening are simultaneously increased, the EGR gas is decreased due to the increase in the vane opening and the EGR gas is increased due to the increase in the EGR control valve opening. An increase in quantity occurs simultaneously. Here, when the response of the vane and the response of the EGR control valve are faster than the intended response, the rate of decrease in the EGR gas amount due to the increase in the vane opening is also the amount of EGR gas due to the increase in the EGR control valve opening. The rate of increase of this is also faster than the intended rate. For this reason, the increase in the decrease rate of the EGR gas amount due to the increase in the vane opening degree and the increase in the increase rate of the EGR gas amount due to the increase in the EGR control valve opening amount are offset, and as a result, as a whole The rate of decrease in the EGR rate is substantially the expected speed, and in some cases, the expected speed. Therefore, if the actual EGR rate is to be reduced when both the vane response and the EGR control valve response are faster than the intended response, the EGR rate deviation integrated value becomes substantially equal to the reference value (or depending on circumstances) Is equal to its reference value).

Thus, when the response of the vane and the response of the EGR control valve are faster than the intended response, the supercharging pressure deviation integrated value is smaller than the reference value, and the EGR rate deviation integrated value becomes the reference value. It becomes substantially equal (or equal to the reference value).

Here, if the amount of vane operation is reduced, the response of the vane becomes slow. Therefore, when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, if the vane operation amount is reduced, the response of the vane is delayed. The change speed of the actual supercharging pressure approaches the intended speed. Therefore, in the fourth embodiment, in this case, the vane operation amount proportional gain is multiplied by the eighth correction value so that the vane operation amount proportional gain becomes small. Thus, if the vane operation amount proportional gain is reduced, the set target vane operation amount is reduced. According to this, the response of the vane becomes slow, and as a result, the change speed of the actual supercharging pressure becomes slow and approaches the intended speed. Then, if the correction of the vane operation amount proportional gain is repeated, the change speed of the actual supercharging pressure finally reaches the intended speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure.

On the other hand, when the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, it is considered that the actual EGR rate is controlled to the target EGR rate with a predetermined followability. be able to. However, as described above, in this case, since the vane operation amount proportional gain is reduced and the response of the vane is delayed, the rate of change in the EGR gas amount due to the change in the vane opening is delayed. In this case, the target EGR rate followability becomes higher than the predetermined followability. On the other hand, if the EGR control valve operation amount is reduced, the response of the EGR control valve is delayed, so that it is possible to suppress the target EGR rate tracking performance from becoming higher than the predetermined tracking performance. Therefore, in the fourth embodiment, when the boost pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value, the EGR control valve operation amount proportional gain is reduced. The eighth correction value is multiplied by the EGR control valve operation amount proportional gain. Thus, if the EGR control valve operation amount proportional gain is decreased, the set target EGR control valve operation amount is decreased. For this reason, it can suppress that target EGR rate followability becomes higher than predetermined followability. Therefore, the actual EGR rate is controlled with a predetermined followability to the target EGR rate.

In addition, according to the correction of the EGR control valve operation amount proportional gain using the above-described eighth correction value, the response of the EGR control valve becomes slow, so that the change in the exhaust pressure caused by the change in the EGR control valve opening degree is reduced. The speed is slow. Also from this, the change speed of the actual supercharging pressure becomes slow and approaches the intended speed. Therefore, the actual supercharging pressure is controlled with a predetermined followability to the target supercharging pressure earlier.

Thus, according to the fourth embodiment, the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value. Therefore, the vane response is also the response of the EGR control valve. Even when the response is faster than the intended response, the actual supercharging pressure can be controlled to the target supercharging pressure with a predetermined followability, and the actual EGR rate can be controlled to the target EGR rate with a predetermined followability. Alternatively, the actual boost pressure and the actual EGR rate can be controlled in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively.

The eighth correction value used for correcting the proportional gain is the target boost pressure when the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value. The followability can be set to a value that can reach the predetermined followability as early as possible and the target EGR rate followability can reach the predetermined followability as early as possible.

Further, the correction of the proportional gain using the eighth correction value is based on the fact that the supercharging pressure deviation integrated value is smaller than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value. This is done with a faster than predetermined response and a faster response of the EGR control valve than the predetermined response. In other words, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected without considering how much the accumulated value of the supercharging pressure deviation deviates from the reference value. Therefore, the eighth correction value does not decrease the target boost pressure follow-up performance and the target EGR rate follow-up performance greatly beyond the predetermined follow-up performance by correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain once. It is considered preferable to set a value as small as possible.

In the fourth embodiment, correction of the proportional gain is performed from the viewpoint of simplifying the correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain and correcting the proportional gain in a well-balanced manner. The correction value is the same as the eighth correction value. However, if necessary, the correction values for correcting each proportional gain may be different from each other.

In the fourth embodiment, the gain is corrected by multiplying the vane operation amount proportional gain by the eighth correction value. However, if necessary, a specific value is set so that the vane operation amount proportional gain is reduced. May be corrected from the vane manipulated variable proportional gain. In the fourth embodiment, the EGR control valve operation amount proportional gain is corrected by multiplying the eighth correction value by the EGR control valve operation amount proportional gain. However, if necessary, the EGR control valve operation amount proportional gain is reduced. Alternatively, the gain may be corrected by subtracting a specific value from the EGR control valve operation amount proportional gain. In this case, from the viewpoint of correcting these proportional gains in a well-balanced manner, it is considered preferable that specific values added to these proportional gains are set to the same value.

In the fourth embodiment, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are corrected based on the deviation of the boost pressure deviation integrated value with respect to the reference value and the deviation of the EGR rate deviation integrated value with respect to the reference value. The Therefore, in the fourth embodiment, the target vane operation amount and the target EGR control valve operation amount are corrected so that the supercharging pressure deviation integrated value matches the reference value and the EGR rate deviation integrated value matches the reference value. It can be said that it is a thing.

Further, the concept regarding the correction of the vane operation amount proportional gain and the EGR control valve operation amount proportional gain of the fourth embodiment can be appropriately applied to the second embodiment and the third embodiment.

As a routine for executing the setting of the target vane operation amount and the target EGR control valve operation amount according to the fourth embodiment, for example, the same routine as that shown in FIG. Further, examples of routines for correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to the fourth embodiment include the routines shown in FIGS.

Next, the routines of FIGS. 10 to 13 will be described. This routine is executed at predetermined time intervals.

When the routines of FIGS. 10 to 13 are started, first, at step 400, the current supercharging pressure deviation integrated value ΣΔPim (k) stored at step 15 of FIG. 4 and the current EGR rate deviation integrated value ΣΔRegr are stored. (K) is acquired. Next, at step 401, the current supercharging pressure deviation integrated value ΣΔPim (k) acquired at step 400 is larger than its upper limit value (that is, a value obtained by adding a predetermined value β to the reference value THpim) (THpim + β). (ΣΔPim (k)> THpim + β) and the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 400 is a lower limit value thereof (that is, a value obtained by subtracting the predetermined value α from the reference value THegr) (THegr−α Is smaller than (ΣΔRegr (k) <THegr−α). Here, if it is determined that ΣΔPim (k)> THpim + β and ΣΔRegr (k) <THegr−α, the routine proceeds to step 402. On the other hand, when it is determined that ΣΔPim (k)> THpim + β and ΣΔRegr (k) <THegr−α is not established, the routine proceeds to step 404.

The value obtained by subtracting the predetermined value α from the reference value THegr of the EGR rate deviation integrated value is used as the lower limit value to be compared with the current EGR rate deviation integrated value ΣΔRegr (k) in Step 401. In step 407 in FIG. 11 and step 422 in FIG. 13, in order to determine whether or not the current EGR rate deviation integrated value ΣΔRegr (k) is substantially equal to the reference value THegr, the reference value THegr of the EGR rate deviation integrated value is used. This is because a value obtained by subtracting the predetermined value α is used. Since the lower limit value is used to determine whether or not the current EGR rate deviation integrated value ΣΔRegr (k) is substantially equal to the reference value, the predetermined value α is set to a very small value.

Also, as the upper limit value compared with the current boost pressure deviation integrated value ΣΔPim (k) in step 401, a value obtained by adding a predetermined value β to the reference value THpim of the boost pressure deviation integrated value is used. In step 410 in FIG. 11 and step 413 in FIG. 12, which will be described later, in order to determine whether or not the current boost pressure deviation integrated value ΣΔPim (k) is substantially equal to the reference value THpim, This is because a value obtained by adding a predetermined value β to the reference value THpim is used. Further, since this upper limit value is used to determine whether or not the current boost pressure deviation integrated value ΣΔPim (k) is substantially equal to the reference value, the predetermined value β is set to an extremely small value. .

In step 401, it is determined that ΣΔPim (k)> THpim + β and ΣΔRegr (k) <THegr−α, and when the routine proceeds to step 402, the current vane operation amount proportional gain GPp (k) and the current EGR are obtained. The control valve operation amount proportional gain GEp (k) is acquired. Next, in step 403, a value (GPp (k) + K1) obtained by adding the first correction value K1 to the current vane operation amount proportional gain GPp (k) acquired in step 402 is a new vane operation amount proportional. A value obtained by subtracting the first correction value K1 from the current EGR control valve operation amount proportional gain GEp (k) acquired in step 402 and set to the gain GPp (k + 1) (GEp (k) −K1) ) Is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 403, and step 403. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

On the other hand, when it is determined in step 401 that ΣΔPim (k)> THpim + β and ΣΔRegr (k) <THegr−α is not satisfied and the routine proceeds to step 404, the current boost pressure deviation integration obtained in step 400 is performed. The value ΣΔPim (k) is larger than the upper limit value (THpim + β) (ΣΔPim (k)> THpim + β) and the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 400 is the upper limit value (that is, its reference It is determined whether or not the value THegr is greater than (THegr + α) (ΣΔRegr (k)> THegr + α). If it is determined that ΣΔPim (k)> THpim + β and ΣΔRegr (k)> THegr + α, the routine proceeds to step 405. On the other hand, if it is determined that ΣΔPim (k)> THpim + β and ΣΔRegr (k)> THegr + α is not established, the routine proceeds to step 407 in FIG.

Note that the value obtained by adding the predetermined value α to the reference value THegr of the EGR rate deviation integrated value is used as the upper limit value compared with the current EGR rate deviation integrated value ΣΔRegr (k) in step 404. In step 407 in FIG. 11 and step 422 in FIG. 13, in order to determine whether or not the current EGR rate deviation integrated value ΣΔRegr (k) is substantially equal to the reference value THegr, the reference value THegr of the EGR rate deviation integrated value is set. This is because a value obtained by adding the predetermined value α is used. Further, since the upper limit value is used to determine whether or not the current EGR rate deviation integrated value ΣΔRegr (k) is substantially equal to the reference value, as described above, the predetermined value α is set to a very small value. Has been.

When it is determined in step 404 that ΣΔPim (k)> THpim + β and ΣΔRegr (k)> THegr + α, and the routine proceeds to step 405, the current vane operation amount proportional gain GPp (k) and the current EGR control valve The manipulated variable proportional gain GEp (k) is acquired. Next, in step 406, a value (GPp (k) × K2) obtained by multiplying the current vane operation amount proportional gain GPp (k) acquired in step 405 by the second correction value K2 is a new vane operation amount. A value obtained by multiplying the current EGR control valve operation amount proportional gain GEp (k) acquired in step 405 by the second correction value K2 while being set to the proportional gain GPp (k + 1) (GEp (k) × K2) is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 406, and step 406 is performed. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

On the other hand, when it is determined in step 404 that ΣΔPim (k)> THpim + β and ΣΔRegr (k)> THegr + α are not satisfied and the routine proceeds to step 407 in FIG. 11, the current boost pressure deviation obtained in step 400 is determined. The integrated value ΣΔPim (k) is larger than the upper limit value (THpim + β) (ΣΔPim (k)> THpim + β), and the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 400 is substantially equal to the reference value THegr. That is, the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 400 is not less than the lower limit value (THegr−α) and not more than the upper limit value (THegr + α) (THegr−α ≦ ΣΔRegr ( k) ≦ THegr + α) is determined. If it is determined that ΣΔPim (k)> THpim + β and THegr−α ≦ ΣΔRegr (k) ≦ THegr + α, the routine proceeds to step 408. On the other hand, if it is determined that ΣΔPim (k)> THpim and that THegr−α ≦ ΣΔRegr (k) ≦ THegr + α is not established, the routine proceeds to step 410.

In step 407, it is determined that ΣΔPim (k)> THpim and THegr−α ≦ ΣΔRegr (k) ≦ THegr + α. When the routine proceeds to step 408, the current vane operation amount proportional gain GPp (k) and the current EGR control valve operation amount proportional gain GEp (k) is acquired. Next, in step 409, a value (GPp (k) × K3) obtained by multiplying the current vane operation amount proportional gain GPp (k) acquired in step 408 by the third correction value K3 is a new vane operation amount. A value obtained by multiplying the current EGR control valve operation amount proportional gain GEp (k) acquired in step 408 by the third correction value K3, and being set to the proportional gain GPp (k + 1) (GEp (k) × K3) is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 408, and step 408 is performed. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

On the other hand, when it is determined in step 407 that ΣΔPim (k)> THpim + β and THegr−α ≦ ΣΔRegr (k) ≦ THegr + α, and the routine proceeds to step 410, the current boost pressure acquired in step 400 is determined. Deviation integrated value ΣΔPim (k) is substantially equal to reference value THpim, that is, current boost pressure deviation integrated value ΣΔPim (k) acquired in step 400 is a lower limit value (that is, a predetermined value from reference value THpim). (the value obtained by subtracting β) which is equal to or greater than (THpim−β) and equal to or less than the upper limit value (THpim + β) (THpim−β ≦ ΣΔPim (k) ≦ THpim + β) and the current EGR acquired in step 400 The rate deviation integrated value ΣΔRegr (k) is smaller than the lower limit (THegr−α) (ΣΔRegr It is determined whether (k) <THegr-α). If it is determined that THpim−β ≦ ΣΔPim (k) ≦ THpim + β and ΣΔRegr (k) <THegr−α, the routine proceeds to step 411. On the other hand, if it is determined that THpim−β ≦ ΣΔPim (k) ≦ THpim + β and ΣΔRegr (k) <THegr−α, the routine proceeds to step 413 in FIG.

Since the lower limit value of the boost pressure deviation integrated value is used in step 410 to determine whether or not the current boost pressure deviation integrated value ΣΔPim (k) is substantially equal to the reference value, as described above. In addition, the predetermined value β is set to a very small value.

In step 410, it is determined that THpim−β ≦ ΣΔPim (k) ≦ THpim + β and ΣΔRegr (k) <THegr−α, and when the routine proceeds to step 411, the current vane operation amount proportional gain GPp (k) And the current EGR control valve operation amount proportional gain GEp (k). Next, in step 412, a value (GPp (k) + K4) obtained by adding the fourth correction value K4 to the current vane operation amount proportional gain GPp (k) acquired in step 411 is a new vane operation amount proportional. A value obtained by subtracting the fourth correction value K4 from the current EGR control valve operation amount proportional gain GEp (k) acquired in step 411 and set to the gain GPp (k + 1) (GEp (k) −K4) ) Is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 412, and step 412. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

On the other hand, in step 410, it is determined that THpim−β ≦ ΣΔPim (k) ≦ THpim + β and ΣΔRegr (k) <THegr−α, and when the routine proceeds to step 413 in FIG. The current supercharging pressure deviation integrated value ΣΔPim (k) is substantially equal to the reference value THpim, that is, the current supercharging pressure deviation integrated value ΣΔPim (k) acquired in step 400 is its lower limit value (THpim−β). The current EGR rate deviation integrated value ΣΔRegr (k), which is equal to or higher than (THpim−β ≦ ΣΔPim (k) ≦ THpim + β) and is equal to or lower than the upper limit value (THpim + β), is obtained in step 400. It is determined whether or not (ΣΔRegr (k)> THegr + α) is greater than the value (THegr−α). If it is determined that THpim−β ≦ ΣΔPim (k) ≦ THpim + β and ΣΔRegr (k)> THegr + α, the routine proceeds to step 414. On the other hand, if it is determined that THpim−β ≦ ΣΔPim (k) ≦ THpim + β and ΣΔRegr (k)> THegr + α, the routine proceeds to step 416.

In step 413, it is determined that THpim−β ≦ ΣΔPim (k) ≦ THpim + β and ΣΔRegr (k)> THegr + α. When the routine proceeds to step 414, the current vane operation amount proportional gain GPp (k) and the current EGR control valve operation amount proportional gain GEp (k) is acquired. Next, in step 415, a value (GPp (k) −K5) obtained by subtracting the fifth correction value K5 from the current vane operation amount proportional gain GPp (k) acquired in step 414 is a new vane operation amount. A value obtained by adding the fifth correction value K5 to the current EGR control valve operation amount proportional gain GEp (k) acquired in step 414, and being set to the proportional gain GPp (k + 1) (GEp (k) + K5 ) Is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 415, and step 415. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

On the other hand, if it is determined in step 413 that THpim−β ≦ ΣΔPim (k) ≦ THpim + β and ΣΔRegr (k)> THegr + α, and the routine proceeds to step 416, the current boost pressure deviation acquired in step 400 is determined. The integrated value ΣΔPim (k) is smaller than the lower limit value (THpim−β) (ΣΔPim (k) <THpim−β), and the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 400 is the lower limit value. It is determined whether or not (ΣΔRegr (k) <THegr−α) is smaller than (THegr−α). If it is determined that ΣΔPim (k) <THpim−β and ΣΔRegr (k) <THegr−α, the routine proceeds to step 417. On the other hand, if it is determined that ΣΔPim (k) <THpim−β and ΣΔRegr (k) <THegr−α is not established, the routine proceeds to step 419 in FIG.

In step 416, it is determined that ΣΔPim (k) <THpim−β and ΣΔRegr (k) <THegr−α, and when the routine proceeds to step 417, the current vane operation amount proportional gain GPp (k) and the current EGR control valve operation amount proportional gain GEp (k) is acquired. Next, in step 418, a value (GPp (k) × K6) obtained by multiplying the current vane operation amount proportional gain GPp (k) acquired in step 417 by the sixth correction value K6 is a new vane operation amount. A value obtained by multiplying the current EGR control valve operation amount proportional gain GEp (k) acquired in step 417 by the sixth correction value K6, and being set to the proportional gain GPp (k + 1) (GEp (k) × K6) is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 418, and step 418. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

On the other hand, if it is determined in step 416 that ΣΔPim (k) <THpim−β and ΣΔRegr (k) <THegr−α is not satisfied, and the routine proceeds to step 419 in FIG. The supercharging pressure deviation integrated value ΣΔPim (k) is smaller than the lower limit value (THpim−β) (ΣΔPim (k) <THpim−β) and the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 400 Is larger than the upper limit value (THegr + α) (ΣΔRegr (k)> THegr + α). If it is determined that ΣΔPim (k) <THpim−β and ΣΔRegr (k)> THegr + α, the routine proceeds to step 420. On the other hand, when it is determined that ΣΔPim (k) <THpim−β and ΣΔRegr (k)> THegr + α is not established, the routine proceeds to step 422.

In step 419, it is determined that ΣΔPim (k) <THpim−β and ΣΔRegr (k)> THegr + α. When the routine proceeds to step 420, the current vane operation amount proportional gain GPp (k) and the current EGR are determined. The control valve operation amount proportional gain GEp (k) is acquired. Next, in step 421, a value (GPp (k) −K7) obtained by subtracting the seventh correction value K7 from the current vane operation amount proportional gain GPp (k) acquired in step 420 is a new vane operation amount. A value obtained by adding the seventh correction value K7 to the current EGR control valve operation amount proportional gain GEp (k) acquired in step 420 and being set to the proportional gain GPp (k + 1) (GEp (k) + K7) ) Is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 421, and step 421. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

On the other hand, if it is determined in step 419 that ΣΔPim (k) <THpim−β and ΣΔRegr (k)> THegr + α is not established, and the routine proceeds to step 422, the current boost pressure deviation integration obtained in step 400 is performed. The value ΣΔPim (k) is smaller than the lower limit value (THpim−β) (ΣΔPim (k) <THpim−β), and the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 400 is the reference value THegr. That is, the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 400 is equal to or higher than the lower limit (THegr−α) and equal to or lower than the upper limit (THegr + α) (THegr−α). It is determined whether or not ≦ ΣΔRegr (k) ≦ THegr + α). If it is determined that ΣΔPim (k) <THpim−β and THegr−α ≦ ΣΔRegr (k) ≦ THegr + α, the routine proceeds to step 423. On the other hand, when it is determined that ΣΔPim (k)> THpim and that THegr−α ≦ ΣΔRegr (k) ≦ THegr + α is not established, the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the current vane operation amount proportional gain GPp (k), and the current EGR control valve operation amount is proportional. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the gain GEp (k).

In step 422, it is determined that ΣΔPim (k) <THpim−β and THegr−α ≦ ΣΔRegr (k) ≦ THegr + α. When the routine proceeds to step 423, the current vane operation amount proportional gain GPp (k) And the current EGR control valve operation amount proportional gain GEp (k). Next, in step 424, a value (GPp (k) × K8) obtained by multiplying the current vane operation amount proportional gain GPp (k) acquired in step 423 by the eighth correction value K8 is a new vane operation amount. A value obtained by multiplying the current EGR control valve operation amount proportional gain GEp (k) acquired in step 423 by the eighth correction value K8, and being set to the proportional gain GPp (k + 1) (GEp (k) × K8) is set to a new EGR control valve operation amount proportional gain GEp (k + 1), and the routine ends. In this case, in step 16 of FIG. 4, the target vane operation amount Mv is calculated from the above equation 1 using the new vane operation amount proportional gain GPp (k + 1) set in step 424, and step 424. The target EGR control valve operation amount Megr is calculated from the above equation 2 using the new EGR control valve operation amount proportional gain GEp (k + 1) set in (1).

In the above-described embodiment, the supercharger 35 is employed as a control target for directly controlling the supercharging pressure. However, in the above-described embodiment, the throttle valve 33 may be employed in addition to the supercharger 35 as a control target for controlling the supercharging pressure.

That is, the throttle valve 33 can variably control the amount of gas sucked into the combustion chamber (hereinafter, this gas is referred to as “intake gas”) by controlling its opening degree. Here, in order to increase the intake gas amount by controlling the throttle valve opening, the throttle valve opening is increased. Here, when the throttle valve opening is increased, the gas easily passes through the throttle valve 33 correspondingly, and as a result, the supercharging pressure increases. When the supercharging pressure increases, the differential pressure between the supercharging pressure and the exhaust pressure decreases accordingly, and as a result, the EGR gas amount decreases. That is, when the throttle valve opening is increased, the supercharging pressure increases and the EGR gas amount decreases. On the other hand, in order to reduce the intake gas amount by controlling the throttle valve opening, the throttle valve opening is decreased. Here, if the throttle valve opening is reduced, the gas is less likely to pass through the throttle valve 33, and as a result, the supercharging pressure is lowered. When the supercharging pressure decreases, the differential pressure between the supercharging pressure and the exhaust pressure increases accordingly, and as a result, the amount of EGR gas increases. That is, when the throttle valve opening is decreased, the supercharging pressure is lowered and the EGR gas amount is increased. That is, the control of the intake gas amount by the throttle valve 33 affects the EGR gas amount (as a result, the EGR rate) and the supercharging pressure. For these reasons, in the above-described embodiment, the throttle valve is also adopted as a control target.

In this case, in the above-described embodiment, it is determined that the vane response is slower than the intended response based on the relationship between the boost pressure deviation integrated value with respect to the reference value and the relationship between the EGR rate deviation integrated value with respect to the reference value. When it is determined that the response of the throttle valve is slower than the intended response, and when the response of the vane is determined to be the intended response, the response of the throttle valve is also determined to be the intended response. Is determined to be faster than the intended response, the throttle valve response is also determined to be faster than the intended response. In the above-described embodiment, when the vane operation amount proportional gain is corrected based on the relationship between the supercharging pressure deviation integrated value with respect to the reference value and the relationship between the EGR rate deviation integrated value with respect to the reference value, the vane operation amount proportional gain is corrected. When the gain is corrected so as to increase, the throttle valve operation amount proportional gain (that is, the proportional gain in PID control of the operation amount input to the throttle valve based on the boost pressure deviation) increases. When the gain is corrected so that the vane operation amount proportional gain becomes smaller, the gain is corrected so that the throttle valve operation amount proportional gain becomes smaller. On the other hand, when the vane opening proportional gain is corrected based on the relationship between the supercharging pressure deviation integrated value with respect to the reference value and the relationship between the EGR rate deviation integrated value with respect to the reference value in the embodiment described above, When the gain is corrected so as to increase, the throttle valve opening proportional gain (that is, the proportional gain in the PID control of the throttle valve opening based on the boost pressure deviation) is corrected, and the vane When the gain is corrected so that the opening proportional gain becomes small, the gain is corrected so that the throttle valve opening proportional gain becomes small.

Next, a fifth embodiment of the present invention will be described. As described above, in the second embodiment, the target vane opening change amount and the target EGR control valve opening change amount are set by the PID control, and the target vane opening change amount conversion formula (that is, the target vane opening change) is set. The target vane operation amount is calculated from the target vane opening change amount using a predetermined conversion formula for calculating the target vane operation amount corresponding to the amount, and the target EGR control valve opening change From the target EGR control valve opening change amount using a quantity conversion equation (that is, a conversion equation determined in advance to calculate the target EGR control valve operation amount corresponding to the target EGR control valve opening change amount). A target EGR control valve operation amount is calculated, an operation amount corresponding to the target vane operation amount is input to the vane, and an operation amount corresponding to the target EGR control valve operation amount is input to the EGR control valve, By Le, the EGR rate is controlled to the target EGR rate with the boost pressure is controlled to the target boost pressure.

On the other hand, in the fifth embodiment, the target throttle valve opening change amount, the target EGR control valve opening change amount, and the target vane opening change amount are set by so-called sliding mode control instead of PID control. . Then, the target throttle valve operation amount is converted using a target throttle valve opening change amount conversion formula (that is, a conversion formula determined in advance for calculating the target throttle valve operation amount corresponding to the target throttle valve opening). Is calculated, a target EGR control valve operation amount is calculated using the target EGR control valve opening change amount conversion equation, and a target vane operation amount is calculated using the target vane opening change amount conversion equation. Then, an operation amount corresponding to the target throttle valve operation amount is input to the throttle valve, an operation amount corresponding to the target EGR control valve operation amount is input to the EGR control valve, and an operation amount corresponding to the target vane operation amount is input to the vane. Thus, the supercharging pressure is controlled to the target supercharging pressure, and the EGR rate is controlled to the target EGR rate.

Next, supercharging pressure and EGR rate control using the sliding mode of the fifth embodiment will be described. In the fifth embodiment, a throttle valve is also employed in addition to the supercharger as a control target for controlling the supercharging pressure.

By the way, in the fifth embodiment, variables are set as follows. That is, the target throttle valve opening change amount to be calculated is expressed by “TDth”, the target EGR control valve opening change amount to be calculated is expressed by “TDegr”, and the target vane opening change amount to be calculated is A matrix U expressed by “TDv” and having these target throttle valve opening change amount, target EGR control valve opening change amount, and target vane opening change amount as elements is defined by the following equation (5).

A linear term related to the throttle valve is represented by “UL1”, a linear term related to the EGR control valve is represented by “UL2”, a linear term related to the vane is represented by “UL3”, and a matrix UL having these linear terms as elements is expressed by the following equation: This is defined in 6.

Further, a nonlinear term related to the throttle valve is expressed by “UNL1”, a nonlinear term related to the EGR control valve is expressed by “UNL2”, a nonlinear term related to the vane is expressed by “UNL3”, and a matrix UNF having these nonlinear terms as elements is expressed by the following equation: 7 to define.

Also, the adaptation term for the throttle valve is represented by “Umap1”, the adaptation term for the EGR control valve is represented by “Umap2”, the adaptation term for the vane is represented by “Umap3”, and a matrix Umap having these adaptation terms as elements is expressed by the following equation: 8 is defined.

The relationship of the following equation 9 is established between the matrices defined by the above equations 5 to 8.

Further, the nominal model (that is, the supercharging pressure and the EGR rate when the operation state of the throttle valve, the EGR control valve, and the vane is controlled by using the state equation regarding the throttle valve, the EGR control valve, and the vane). The weight matrix S calculated from the model representing the behavior is defined by the following equation 10, the expanded system Be of the nominal model input matrix is defined by the following equation 11, and the expanded system Ae of the system matrix of the nominal model is defined by the following equation: 12 to define. The weight matrix S represents a sliding surface in the sliding mode, and this is called a hyperplane.

Further, the integrated value of the value obtained by multiplying the weight gain by the EGR rate deviation is represented by “Xe1”, the integrated value of the value obtained by multiplying the weight gain by the supercharging pressure deviation is represented by “Xe2”, and the EGR rate is represented by “Xe3”. The supercharging pressure is expressed by “Xe4”, and a matrix Xe whose elements are the integrated value, the EGR rate, and the supercharging pressure is defined by the following equation (13).

The unit matrix expansion system Ee is defined by the following equation (14).

Further, the target EGR rate is represented by “TRegr”, the target supercharging pressure is represented by “TPim”, and a matrix R having these target EGR rate and target supercharging pressure as elements is defined by the following equation (15).

Then, using the matrixes of the above equations 12 to 15, the matrix UL of the above equation 9 is expressed by the following equation 16.

Further, the gain ratio of the nonlinear term related to the throttle valve is represented by “J1”, the gain ratio of the nonlinear term related to the EGR control valve is represented by “J2”, and the gain ratio of the nonlinear term related to the vane is represented by “J3”. A matrix J is defined by the following Expression 17.

Further, the distance from the hyperplane related to the throttle valve is represented by “σ1”, the distance from the hyperplane related to the EGR control valve is represented by “σ2”, the distance from the hyperplane related to the vane is represented by “σ3”, and these distances are expressed as A matrix (that is, a switching function) σ as an element is defined by the following equation 18. The distance from the hyperplane changes according to the supercharging pressure deviation integrated value and the EGR rate deviation integrated value, and increases as the supercharging pressure deviation integrated value increases or the EGR rate deviation integrated value increases.

When the matrix having the gain coefficient for each nonlinear term as an element is represented by “Jk”, the matrix of the above equation 9 is obtained by using the matrix of the above equation 10, the above equation 11, the above equation 17, and the above equation 18. UNL is expressed by the following equation 19. Since the distances σ1 to σ3 from the nominal increase as the supercharging pressure deviation integrated value increases or as the EGR rate deviation integrated value increases, the nonlinear term UNL also increases the supercharging pressure deviation integrated as can be seen from the following equation 19. The larger the value or the larger the EGR rate deviation integrated value, the larger the value.

Therefore, when the above equation 16 and the above equation 19 are used, the above equation 9 is expressed by the following equation 20.

In the fifth embodiment, the target throttle valve opening change amount, the target EGR control valve opening change amount, and the target vane opening change amount are calculated (that is, set) using the above equation 20, and these are calculated. The target throttle valve operation amount, the target EGR control valve operation amount, and the target vane operation amount are calculated based on the target throttle opening change amount, the target EGR control valve opening change amount, and the target vane opening change amount. The calculated target throttle valve operation amount, target EGR control valve operation amount, and target vane operation amount are input to the throttle valve, EGR control valve, and vane, respectively. Thereby, the supercharging pressure and the EGR rate are controlled to the target supercharging pressure and the target EGR rate, respectively.

In the fifth embodiment, a weight gain (hereinafter, this gain is referred to as “EGR rate weight gain”) GE multiplied by the above-described EGR rate deviation and a weight gain (hereinafter, this gain) that is multiplied by the above-described supercharging pressure deviation. Is a gain to be corrected based on the supercharging pressure deviation integrated value and the EGR rate deviation integrated value.

That is, in the fifth embodiment, as in the first embodiment, the boost pressure deviation integrated value calculated during engine operation is compared with the reference value, and the EGR rate deviation integrated value calculated during engine operation is compared. The value is compared with its reference value.

Here, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, a predetermined value (hereinafter referred to as this value) is set so that the supercharging pressure weight gain GP becomes large. The first correction value is set to the EGR rate weight gain GE so that the gain is corrected and the EGR rate weight gain GE is reduced by adding the value to the supercharging pressure weight gain GP. The same gain is corrected by subtracting from.

Further, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, a predetermined value larger than 1 so that the EGR rate weight gain GE is increased ( By multiplying the EGR rate weight gain GE by this value (hereinafter referred to as “second correction value”), the gain is corrected and the second correction value is set to the boost pressure so that the boost pressure weight gain GP is increased. The gain is corrected by multiplying by the weight gain GP.

Further, when the boost pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to (or equal to) the reference value, the boost pressure weight gain GP is increased. By multiplying the boost pressure gain gain GP by a predetermined value larger than 1 (hereinafter referred to as “third correction value”), the gain is corrected and the EGR rate weight gain GE is increased. In this way, the third correction value is multiplied by the EGR rate weight gain GE to correct the gain.

In addition, when the relationship between the supercharging pressure deviation integrated value with respect to the reference value and the relationship between the EGR rate deviation integrated value with respect to the reference value is other than the relationship mentioned above, the supercharging pressure weight gain is also the EGR rate weight gain. Is not corrected.

As described above, the supercharging pressure weight gain and the EGR rate weight gain are corrected, and these corrected gains are the target throttle valve opening change amount, the target EGR control valve opening change amount, and the target vane opening change amount, respectively. For the same reason as described in relation to the first embodiment, the supercharging pressure can be controlled to the target supercharging pressure with a predetermined followability and the EGR rate can be set to the target EGR. The effect of being able to control the rate with predetermined followability, or the effect of being able to control the actual boost pressure and the actual EGR rate in a balanced manner with respect to the target boost pressure and the target EGR rate, respectively. Is obtained.

In the fifth embodiment, the supercharging pressure weight gain and the EGR rate weight gain are corrected based on the deviation of the supercharging pressure deviation integrated value with respect to the reference value and the deviation of the EGR rate deviation integrated value with respect to the reference value. Therefore, as a result, in the fifth embodiment, the target vane opening change amount and the target EGR are set such that the supercharging pressure deviation integrated value matches the reference value and the EGR rate deviation integrated value matches the reference value. It can also be said that the amount of change in the control valve opening is corrected.

Further, the concept of correction for the proportional gain of the second to fourth embodiments may be applied to the correction for the supercharging pressure weight gain and the EGR rate weight gain of the fifth embodiment.

Next, an example of a routine for setting the target vane operation amount, the target EGR control valve operation amount, and the target throttle valve operation amount according to the fifth embodiment will be described. This routine is shown in FIG. 14 and is executed at predetermined time intervals. Further, Step 50 to Step 55 in FIG. 14 are the same as Step 10 to Step 15 in FIG. 4, respectively, and description of these steps will be omitted.

In the routine of FIG. 14, in step 56, the target vane opening change amount TDv, the target EGR control valve opening change amount TDegr, and the target throttle valve opening change amount TDth are calculated using the above equation 20. Next, at step 57, based on the target vane opening change amount TDv, the target EGR control valve opening change amount TDegr, and the target throttle valve opening change amount TDth calculated at step 56, the target vane operation amount Mv, the target The EGR control valve operation amount Megr and the target throttle valve operation amount Mth are calculated, and the routine ends.

Further, as routines for executing correction of the supercharging pressure weight gain and the EGR rate weight gain according to the fifth embodiment, the routines shown in FIGS. 15 and 16 can be exemplified. Note that step 500, step 501, step 504, and step 507 in FIGS. 15 and 16 are the same as step 100, step 101, step 104, and step 107 in FIGS. 5 and 6, respectively. Description of these steps is omitted. The remaining steps of FIGS. 15 and 16 are the same as the supercharging pressure weight gains GP and EGR, respectively, in which the vane operation amount proportional gain GPp and the current EGR control valve operation amount proportional gain GEp in the remaining steps of FIGS. Since these steps are changed to the rate weight gain GE, description of these steps is also omitted.

In the above-described embodiment, the vane operation amount proportional gain and the EGR control valve operation amount proportional gain are set so that the supercharging pressure deviation integrated value matches the reference value and the EGR rate deviation integrated value matches the reference value. Is corrected, the vane opening proportional gain and the EGR control valve opening proportional gain are corrected, or the supercharging pressure weight gain and the EGR rate weight gain are corrected. However, in the above-described embodiment, the vane operation is performed so that the ratio between the supercharging pressure deviation integrated value and the EGR rate deviation integrated value coincides with the ratio between the reference value of the supercharging pressure deviation integrated value and the EGR rate deviation integrated value. The amount proportional gain and the EGR control valve operation amount proportional gain are corrected, the vane opening proportional gain and the EGR control valve opening proportional gain are corrected, or the boost pressure weight gain and the EGR rate weight gain are corrected. Also good.

Next, the vane operation amount proportional gain and the EGR are set so that the ratio of the supercharging pressure deviation integrated value and the EGR rate deviation integrated value matches the ratio of the reference value of the supercharging pressure deviation integrated value and the EGR rate deviation integrated value. One of the embodiments in which the control valve operation amount proportional gain is corrected, the vane opening proportional gain and the EGR control valve opening proportional gain are corrected, or the supercharging pressure weight gain and the EGR rate weight gain are corrected. This will be described as a sixth embodiment.

In the sixth embodiment, similarly to the first embodiment, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is smaller than the reference value, the vane operation amount proportional gain is increased. By adding a predetermined value (hereinafter referred to as “first correction value”) to the vane operation amount proportional gain so as to increase, the gain is corrected and the EGR control valve operation amount proportional gain is decreased. The first correction value is subtracted from the EGR control valve operation amount proportional gain to correct the gain. At this time, the target vane operation amount and the target EGR control valve operation amount calculated from the

above equations

1 and 2 using the corrected vane operation amount proportional gain and the corrected EGR control valve operation amount proportional gain. Is inputted to the vane and the EGR control valve, respectively, and the supercharging pressure deviation integrated value and the EGR rate deviation integrated value when the supercharging pressure and the EGR rate are controlled (hereinafter, this ratio is referred to as “deviation integrated value ratio”). (Referred to as the “reference value ratio”) (or the deviation integrated value) so that the ratio of the reference value of the supercharging pressure deviation integrated value and the reference value of the EGR rate deviation integrated value (hereinafter referred to as “reference value ratio”) The first correction value is set so that the ratio approaches the reference value ratio.

Further, in the sixth embodiment, as in the first embodiment, when the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is larger than the reference value, the EGR control valve operation is performed. The gain is corrected and the vane is corrected by multiplying the EGR control valve operation amount proportional gain by a predetermined value larger than 1 (hereinafter referred to as “second correction value”) so that the amount proportional gain becomes large. The gain is corrected by multiplying the vane manipulated variable proportional gain by the second correction value so that the manipulated variable proportional gain is increased. At this time, the target vane operation amount and the target EGR control valve operation amount calculated from the

above equations

1 and 2 using the corrected vane operation amount proportional gain and the corrected EGR control valve operation amount proportional gain. Are input to the vane and EGR control valves, respectively, so that the deviation integrated value ratio becomes the same as the reference value ratio when the supercharging pressure and the EGR rate are controlled (or the deviation integrated value ratio is the reference value). The second correction value is set so as to approach the ratio.

In the sixth embodiment, similarly to the first embodiment, the supercharging pressure deviation integrated value is larger than the reference value and the EGR rate deviation integrated value is substantially equal to the reference value (or equal to the reference value). ), The vane manipulated variable proportional gain is multiplied by a predetermined value larger than 1 (hereinafter referred to as “third correction value”) so that the vane manipulated variable proportional gain is increased. The gain is corrected by multiplying the EGR control valve operation amount proportional gain by the third correction value so that the EGR control valve operation amount proportional gain is increased. At this time, the target vane operation amount and the target EGR control valve operation amount calculated from the

above equations

1 and 2 using the corrected vane operation amount proportional gain and the corrected EGR control valve operation amount proportional gain. Is input to the vane and the EGR control valve, respectively, so that the deviation integrated value ratio becomes the same as the reference value ratio when the supercharging pressure and the EGR rate are controlled (or the deviation integrated value ratio is the reference value). The third correction value is set so as to approach the ratio.

Further, in the sixth embodiment, similarly to the first embodiment, when the relationship between the supercharging pressure deviation integrated value with respect to the reference value and the relationship between the EGR rate deviation integrated value with respect to the reference value is other than the relationship mentioned above. Neither the vane operation amount proportional gain nor the EGR control valve operation amount proportional gain is corrected.

According to the sixth embodiment, the target vane operation amount and the target EGR control valve operation amount are corrected so that the deviation integrated value ratio matches the reference value ratio. Here, if the deviation integrated value ratio matches the reference value ratio, at least the relationship between the target boost pressure tracking capability and the target EGR rate tracking capability is the desired relationship (that is, the vane response is also the EGR control valve). Is also close to the relationship between the target boost pressure follow-up property and the target EGR rate follow-up property when the response is an intended response. Therefore, the target boost pressure followability and the target EGR rate followability are corrected with a good balance.

As a routine for executing the setting of the target vane operation amount and the target EGR control valve operation amount according to the sixth embodiment, for example, the same routine as that shown in FIG. Examples of routines for correcting the vane operation amount proportional gain and the EGR control valve operation amount proportional gain according to the sixth embodiment include the routines shown in FIGS. 17 and 18.

Next, the routines of FIGS. 17 and 18 will be described. This routine is executed at predetermined time intervals. Also, steps 600, 601, 602 to 604, 605 to 607, 608, and 609 of the routines of FIGS. Since these steps are the same as 107 to 108 and 109, description of these steps is omitted.

In the routines of FIGS. 17 and 18, the supercharging pressure deviation integrated value ΣΔPim (k) acquired in step 600 in step 601 is larger than the reference value THpim (ΣΔPim (k)> THpim) and acquired in step 600. Further, the current EGR rate deviation integrated value ΣΔRegr (k) is smaller than the lower limit value (that is, the value obtained by subtracting the predetermined value α from the reference value THegr) (THegr−α) (ΣΔRegr (k) <THegr−α). When the routine proceeds to step 601A, the deviation integrated value ratio (that is, the supercharging pressure deviation integrated value ΣΔPim (k) acquired in step 600 with respect to the EGR rate deviation integrated value ΣΔRegr (k) acquired in step 600). ))) ΣΔPim (k) / ΣΔRegr (k) is calculated. Next, in step 601B, when the vane operation amount proportional gain GPp and the EGR control valve operation amount proportional gain GEp corrected in the subsequent step 603 are used for setting the vane operation amount and the EGR control valve operation amount, the deviation integrated value. The ratio can be matched with the reference value ratio (that is, the ratio of the reference value of the boost pressure deviation integrated value to the reference value of the EGR rate deviation integrated value) (or the deviation integrated value ratio can be made closer to the reference value ratio). One correction value K1 is set based on the deviation integrated value ratio ΣΔPim (k) / ΣΔRegr (k) calculated in step 601A. In this case, in step 603, the gain is corrected by adding the first correction value K1 set in step 601B to the current vane operation amount proportional gain GPp (k) acquired in step 602. By subtracting the first correction value K1 set in step 601B from the current EGR control valve operation amount proportional gain GEp (k) acquired in 602, the gain is corrected.

In the routines of FIGS. 17 and 18, the current boost pressure deviation integrated value ΣΔPim (k) acquired in step 600 in step 604 is larger than the reference value THpim (ΣΔPim (k)> THpim) and step The current EGR rate deviation integrated value ΣΔRegr (k) acquired at 600 is larger than its upper limit value (that is, a value obtained by adding a predetermined value α to the reference value THegr) (THegr + α) (ΣΔRegr (k)> THegr + α). When the routine proceeds to step 604A, the deviation integrated value ratio (that is, the supercharging pressure deviation integrated value ΣΔPim (k) acquired in step 600 with respect to the EGR rate deviation integrated value ΣΔRegr (k) acquired in step 600). ))) ΣΔPim (k) / ΣΔRegr (k) is calculated. Next, in step 604B, when the vane operation amount proportional gain GPp and the EGR control valve operation amount proportional gain GEp corrected in the subsequent step 606 are used for setting the vane operation amount and the EGR control valve operation amount, the deviation integrated value. The ratio can be matched with the reference value ratio (that is, the ratio of the reference value of the boost pressure deviation integrated value to the reference value of the EGR rate deviation integrated value) (or the deviation integrated value ratio can be made closer to the reference value ratio). 2 correction value K2 is set based on the deviation integrated value ratio ΣΔPim (k) / ΣΔRegr (k) calculated in step 604A. In this case, in step 606, the current vane operation amount proportional gain GPp (k) acquired in step 605 is multiplied by the second correction value K2 set in step 604B, thereby correcting the gain. The current EGR control valve operation amount proportional gain GEp (k) acquired in 605 is multiplied by the second correction value K2 set in step 604B to correct the gain.

In the routines shown in FIGS. 17 and 18, in step 607, the current supercharging pressure deviation integrated value ΣΔPim (k) acquired in step 600 is larger than the reference value THpim (ΣΔPim (k)> THpim) and The current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 600 is substantially equal to the reference value THegr, that is, the current EGR rate deviation integrated value ΣΔRegr (k) acquired in step 600 is its lower limit value ( When it is determined that (THegr−α ≦ ΣΔRegr (k) ≦ THegr + α) which is equal to or higher than THegr−α) and equal to or lower than the upper limit value (THegr + α) and the routine proceeds to Step 607A, the deviation integrated value ratio (ie, Step In step 600 for the EGR rate deviation integrated value ΣΔRegr (k) acquired in step 600 Obtained by the ratio of supercharging pressure deviation integrated value ΣΔPim (k)) ΣΔPim (k) / ΣΔRegr (k) is calculated. Next, in step 607B, the deviation integrated value when the vane operation amount proportional gain GPp and the EGR control valve operation amount proportional gain GEp corrected in the subsequent step 609 are used for setting the vane operation amount and the EGR control valve operation amount. The ratio can be matched with the reference value ratio (that is, the ratio of the reference value of the boost pressure deviation integrated value to the reference value of the EGR rate deviation integrated value) (or the deviation integrated value ratio can be made closer to the reference value ratio). 3 correction value K3 is set based on deviation integrated value ratio ΣΔPim (k) / ΣΔRegr (k) calculated in step 607A. In this case, in step 609, the current vane manipulated variable proportional gain GPp (k) acquired in step 608 is multiplied by the third correction value K3 set in step 607B, thereby correcting the gain. The current EGR control valve operation amount proportional gain GEp (k) acquired in 608 is multiplied by the third correction value K3 set in step 607B to correct the gain.

The above-described embodiment is an embodiment when the present invention is applied to a compression self-ignition internal combustion engine (so-called diesel engine). However, the control device of the present invention is also applicable to a spark ignition type internal combustion engine (so-called gasoline engine).

Claims

A first control target that controls a first control amount that is one of two control amounts that affect each other, and a second control amount that controls a second control amount that is the remaining one of the two control amounts that affect each other. A control apparatus for an internal combustion engine having two control targets, wherein a first control amount to be targeted is set as a target first control amount and a second control amount to be targeted is set as a target second control amount Then, an operation amount to be input to the first control target in order to make the first control amount reach the target first control amount and make the second control amount reach the target second control amount is set as the target first operation amount. The operation amount to be input to the second control object is set as the target second operation amount, and the operation amount corresponding to the target first operation amount is input to the first control object and the operation amount corresponding to the target second operation amount. Is input to the second control target to target the first control amount. A control apparatus for controlling the target second controlled variable of the second control quantity to control the first control amount,
During the operation of the internal combustion engine, the integrated value of the deviation of the actual first control amount with respect to the target first control amount is calculated as the first control amount deviation integrated value, and the deviation of the actual second control amount with respect to the target second control amount Is calculated as the second controlled variable deviation integrated value, and the target first manipulated variable and target second manipulated variable are corrected based on the first controlled variable deviation integrated value and the second controlled variable deviation integrated value. Control device for an internal combustion engine.
A first controlled variable deviation integrated value to be compared with the first controlled variable deviation integrated value is prepared as a first threshold value, and a second controlled variable deviation integrated value to be compared with the second controlled variable deviation integrated value Is prepared as the second threshold value, and when the target first operation amount and the target second operation amount are corrected based on the first control amount deviation integrated value and the second control amount deviation integrated value, The control amount deviation integrated value is compared with the first threshold value, the second control amount deviation integrated value is compared with the second threshold value, and the comparison result of the first control amount deviation integrated value with respect to the first threshold value is 2. The control device for an internal combustion engine according to claim 1, wherein the target first operation amount and the target second operation amount are corrected based on a comparison result of the second control amount deviation integrated value with respect to the second threshold value.
Based on the comparison result of the first control amount deviation integrated value with respect to the first threshold value and the comparison result of the second control amount deviation integrated value with respect to the second threshold value, the target first operation amount and the target second operation amount are obtained. When the correction is made, the first control amount deviation integrated value coincides with the first threshold value and the second control amount deviation integrated value coincides with the second threshold value, or the first control amount deviation integrated value. The target first manipulated variable and the target second manipulated variable are corrected so that a ratio between the value and the second control amount deviation integrated value matches a ratio between the first threshold and the second threshold. 3. The control device for an internal combustion engine according to 2.
A first control target that controls a first control amount that is one of two control amounts that affect each other, and a second control amount that controls a second control amount that is the remaining one of the two control amounts that affect each other. A control device for an internal combustion engine having two control targets, wherein a control amount to be targeted as a first control amount is set as a target first control amount and a control amount to be targeted as a second control amount is set as a target Set as the second control amount, and target the operating state of the first control target that should be the target in order to make the first control amount reach the target first control amount and make the second control amount reach the target second control amount. The first controlled object is set as the first operating state, the operating state of the second controlled object to be targeted is set as the target second operating state, and the operating state of the first controlled object becomes the target first operating state. And controlling the operation state of the second controlled object The first control amount is controlled to the target first control amount and the second control amount is controlled to the target second control amount by controlling the operation state of the second control target so that the operation state becomes the target second operation state. In the control device, during operation of the internal combustion engine, the integrated value of the deviation of the actual first control amount with respect to the target first control amount is calculated as the first control amount deviation integrated value, and the actual first control amount with respect to the target second control amount is calculated. The integrated value of the deviations of the two controlled variables is calculated as the second controlled variable deviation integrated value. Based on the first controlled variable deviation integrated value and the second controlled variable deviation integrated value, the target first operating state and the target second A control device for an internal combustion engine in which the operating state is corrected.
A first controlled variable deviation integrated value to be compared with the first controlled variable deviation integrated value is prepared as a first threshold value, and a second controlled variable deviation integrated value to be compared with the second controlled variable deviation integrated value Is prepared as the second threshold value, and when the target first operation state and the target second operation state are corrected based on the first control amount deviation integrated value and the second control amount deviation integrated value, The control amount deviation integrated value is compared with the first threshold value, the second control amount deviation integrated value is compared with the second threshold value, and the comparison result of the first control amount deviation integrated value with respect to the first threshold value is The control apparatus for an internal combustion engine according to claim 4, wherein the target first operation state and the target second operation state are corrected based on a comparison result of the second control amount deviation integrated value with respect to the second threshold value.
Based on the comparison result of the first control amount deviation integrated value with respect to the first threshold and the comparison result of the second control amount deviation integrated value with respect to the second threshold, the target first operation state and the target second operation state are determined. When the correction is made, the first control amount deviation integrated value coincides with the first threshold value and the second control amount deviation integrated value coincides with the second threshold value, or the first control amount deviation integrated value. The target first operation state and the target second operation state are corrected so that a ratio between the value and the second control amount deviation integrated value matches a ratio between the first threshold value and the second threshold value. 5. A control device for an internal combustion engine according to 5.
The first threshold value and the second threshold value are set to values that can be taken when the response of the first control target is a predetermined response and the response of the second control target is a predetermined response. The control apparatus for an internal combustion engine according to any one of 3, 5, and 6.