JP5370059B2 - Supercharger control device - Google Patents

Description

  The present invention relates to a technical field of a supercharger control device that controls a supercharger having, for example, a compressor with a variable diffuser.

  As this type of device, there is one that controls the behavior of a supercharger mounted on a vehicle such as an automobile in accordance with the driving situation of the vehicle. The supercharger is controlled so as to increase its operating efficiency, for example, by changing the vane opening degree of the diffuser attached to the compressor. Specifically, a technique has been proposed in which the intake efficiency of the initial stage of acceleration is increased by increasing the vane opening of the diffuser more than usual during vehicle acceleration (see, for example, Patent Documents 1 and 2).

  An apparatus for controlling a supercharger having a compressor bypass for allowing air to flow into an internal combustion engine without passing through a compressor is known (for example, see Patent Document 3). Furthermore, an apparatus for controlling an EGR (Exhaust Gas Recirculation) system that recirculates exhaust gas from an internal combustion engine to the intake side is also known (see, for example, Patent Documents 4 to 6).

Japanese Utility Model Publication No. 61-186741 JP 2007-132232 A JP 2007-071150 A JP 2000-205053 A JP 2008-175139 A JP 2008-185008 A

  However, in the technique for controlling the vane opening of the diffuser as described in Patent Documents 1 and 2 described above, although the intake opening can be accelerated by increasing the vane opening during acceleration, At that time, the restriction effect of the original variable diffuser is reduced. That is, the above-described technique has a technical problem that the function of the variable diffuser cannot be sufficiently exhibited, and as a result, the operation efficiency of the supercharger may be reduced.

  This invention is made | formed in view of the problem mentioned above, for example, and makes it a subject to provide the supercharger control apparatus which can raise the operating efficiency of a supercharger very effectively.

  In order to solve the above problems, a supercharger control device of the present invention is a supercharger control device mounted on a vehicle including an internal combustion engine and a supercharger having a compressor and a turbine with a variable diffuser, An opening degree control means for controlling the vane opening degree of the variable diffuser based on predetermined information, an acceleration detection means for detecting the acceleration of the vehicle, and a pressure for detecting an inlet side pressure and an outlet side pressure in the compressor A value based on the predetermined information when detecting the acceleration and detecting that the acceleration on the outlet side and the pressure on the outlet side are lower than the pressure on the inlet side. Adjusting means for controlling the opening degree control means so as to be larger.

  According to the supercharger control device of the present invention, for example, a supercharger (so-called turbocharger) mounted on a vehicle such as an automobile traveling with an internal combustion engine as power is controlled. The supercharger is provided with a compressor and a turbine with a variable diffuser, and the operation efficiency can be increased by adjusting the vane opening of the diffuser. Specifically, at the time of operation of the supercharger, the vane opening degree of the diffuser is controlled based on predetermined information by the opening degree control means provided in the supercharger control device of the present invention. Here, the “predetermined information” means that the operation efficiency of the supercharger is maximized during normal driving of the vehicle (that is, during driving except for a situation that occurs only temporarily such as during rapid acceleration). The information is theoretically, experimentally or empirically set in advance so as to increase.

  However, the control of the supercharger may not be able to be performed at the time of sudden acceleration of the vehicle only by the control of the vane opening based on the predetermined information described above. Specifically, for example, when the inflow of air into the compressor rapidly increases due to sudden acceleration of the vehicle, for example, there is a possibility that resistance to the air into which the diffuser flows is caused. For this reason, a supercharging delay may occur immediately after the start of acceleration. The supercharging delay causes deterioration of, for example, emission, fuel consumption, and drivability.

  Here, the supercharger control device of the present invention is particularly provided with acceleration detection means for detecting acceleration of the vehicle and pressure detection means for detecting the pressure on the inlet side and the pressure on the outlet side in the compressor. In the acceleration detection means, for example, by monitoring the engine speed, the accelerator opening, etc., the acceleration of the vehicle that cannot be handled by the control of the vane opening based on the predetermined information is detected. That is, “acceleration” here does not simply mean a state in which the vehicle speed is increasing, but the vehicle speed is so high that the operation efficiency of the supercharger deteriorates under normal control. It means a rapidly rising state. Further, in the pressure detection means, the pressure is detected by, for example, a pressure meter or an air flow meter provided near the intake port and the exhaust port of the compressor.

  In the present invention, when the acceleration detection means detects acceleration of the vehicle and the pressure on the outlet side of the compressor detected by the pressure detection means is lower than the pressure on the inlet side, the opening degree control means is controlled by the adjustment means. Be controlled. Specifically, the opening degree control means is controlled so that the vane opening degree of the variable diffuser becomes larger than a value based on predetermined information.

  By controlling the opening control means as described above, it is possible to prevent the diffuser from becoming the resistance of the air that is about to flow into the compressor when the inflow air amount rapidly increases due to acceleration of the vehicle. . Therefore, it is possible to prevent the supercharging delay from occurring. In addition, since the adjusting means determines whether or not to control the opening degree control means based on the pressure on the inlet side and outlet side of the compressor, simply increasing the vane opening degree during acceleration In comparison, the vane throttling effect can be obtained efficiently. That is, the function as a compressor with a variable diffuser can be efficiently exhibited.

  The vane opening controlled by the adjusting means is typically fully open (in other words, the variable diffuser is not operating), but the opening based on predetermined information (that is, normal running of the vehicle) If the opening is larger than the opening at the time, the above-described effects can be obtained accordingly.

  As described above, according to the supercharger control device of the present invention, the operation efficiency of the supercharger can be extremely effectively increased.

  In one aspect of the supercharger control device of the present invention, the recirculation means for recirculating the exhaust gas from the exhaust side to the intake side of the internal combustion engine, and when the acceleration is detected, the recirculation of the exhaust gas by the recirculation means is stopped. And a reflux control means.

  According to this aspect, the recirculation means (so-called EGR system) for recirculating the exhaust gas from the exhaust side to the intake side of the internal combustion engine is provided. In the recirculation means, when acceleration is detected by the acceleration detection means, the recirculation of the exhaust gas is stopped by the recirculation control means. In other words, when the adjustment means controls the opening degree control means, exhaust gas recirculation by the recirculation means is stopped.

  When the recirculation of the exhaust gas by the recirculation means is stopped, the exhaust gas recirculated to the intake side of the internal combustion engine temporarily decreases, so that the pressure between the compressor and the internal combustion engine greatly decreases. That is, a situation in which a supercharging delay is very likely to occur.

  However, in this aspect, as described above, since the vane opening degree of the diffuser is controlled by the adjusting means, it is possible to prevent the diffuser from becoming the resistance of the inflow air during acceleration. Therefore, even if it becomes a situation where a supercharging delay is likely to occur, the supercharging delay can be reliably prevented.

  In the aspect further including the above-described recirculation means, the recirculation means includes first recirculation means for recirculating the exhaust gas between the internal combustion engine and the turbine between the compressor and the internal combustion engine, and the compressor from the turbine outlet side. And a second recirculation means for recirculating the exhaust gas on the inlet side of the exhaust gas. The recirculation by the first recirculation means is stopped and the recirculation by the second recirculation means is performed in the adjusting means. In the state, when the second reflux means is stopped, the opening degree control means may not be controlled.

  In this case, the recirculation means includes a first recirculation means for recirculating the exhaust gas between the internal combustion engine and the turbine between the compressor and the internal combustion engine, and a second recirculation means for recirculating the exhaust gas from the turbine outlet side to the compressor inlet side. Contains.

  The first recirculation means is, for example, one that recirculates exhaust gas from the vicinity of the exhaust port of the internal combustion engine to the vicinity of the intake port (so-called HPL: High Pressure Loop). The second recirculation means is, for example, a device that recirculates the exhaust from the downstream of the three-way catalyst that purifies the exhaust to the upstream of the compressor (so-called LPL: Low Pressure Loop).

  Here, in this embodiment, in particular, when the second refluxing unit is stopped in a state where the refluxing by the first refluxing unit is stopped and the refluxing by the second refluxing unit is being performed, the opening by the adjusting unit is performed. The degree control means is not controlled. That is, when both the first reflux means and the second reflux means are not refluxed from the state where only the reflux by the second reflux means is performed, the control of the opening degree control means by the adjusting means is performed. Is not done.

  Under the circumstances described above, the first reflux means for returning the exhaust gas to the outlet side of the compressor is stopped, so that even if the second reflux means is stopped, the pressure on the outlet side of the compressor is greatly reduced. There is nothing. Therefore, compared with the case where the recirculation | reflux by a 1st recirculation | reflux means is stopped, possibility that a supercharging delay will generate | occur | produce is low. Therefore, if the control of the opening degree control means by the adjusting means is not performed, the vane opening degree control based on the predetermined information is performed, and the function as a compressor with a variable diffuser can be efficiently exhibited.

  In another aspect of the supercharger control device of the present invention, the adjusting means stops the control of the opening degree control means after a predetermined period has elapsed since the start of the opening degree control means.

  According to this aspect, the elapsed time since the adjustment means starts controlling the opening degree control means is counted, and after the predetermined period, the control of the opening degree control means by the adjustment means is stopped. That is, the control returns to the control based on the predetermined information. Here, the “predetermined period” is a period from the start of the control of the opening degree control means by the adjusting means to the transition to a state where the supercharging delay is unlikely to occur. Or empirically required.

  Increasing the vane opening during acceleration by the adjusting means can effectively prevent the supercharging delay as described above, but on the other hand, the vane opening continues to increase even when the supercharging delay hardly occurs. The original function of the compressor with a variable diffuser will be lost.

  However, in this aspect, when the control of the opening degree control means by the adjusting means is stopped after the predetermined period has elapsed, and the supercharging delay is unlikely to occur, the control for the variable diffuser vane opening degree is performed. It returns to the control based on the information. Therefore, the original function of a compressor with a variable diffuser can be exhibited very efficiently.

  In another aspect of the supercharger control device of the present invention, the adjusting means has a deviation between the outlet side pressure and a reference pressure set as a reference of the outlet side pressure within a predetermined range. At this time, the control of the opening degree control means is stopped.

  According to this aspect, the difference between the pressure on the outlet side of the compressor detected by the pressure detection means and the reference pressure set as a reference for the pressure on the outlet side of the compressor is monitored. The “reference pressure” is a pressure set in advance based on the pressure on the outlet side of the compressor during normal traveling of the vehicle, and is determined theoretically, experimentally, or empirically, for example.

  Here, in particular, the control of the opening degree control means by the adjusting means is stopped when the detected difference between the outlet pressure of the compressor and the reference pressure falls within a predetermined range. Here, the “predetermined range” is a range for determining that the detected pressure on the outlet side of the compressor is in a state in which it is difficult for the supercharging delay to occur. It can be arbitrarily set based on the characteristics of the entire system provided with the supercharger.

  In this aspect, when the deviation between the detected pressure and the reference pressure becomes sufficiently small, the control of the opening degree control means by the adjusting means is stopped, so that it becomes difficult to cause a supercharging delay. The control on the vane opening degree of the variable diffuser is returned to the control based on the predetermined information. Therefore, the original function of a compressor with a variable diffuser can be exhibited very efficiently.

  In another aspect of the supercharger control device of the present invention, the adjustment means stops the control of the opening degree control means when the change in pressure on the outlet side starts to increase.

  According to this aspect, the change in the pressure on the outlet side of the compressor detected by the pressure detecting means is monitored. Then, the control of the opening degree control means by the adjusting means is stopped when the change in the pressure on the outlet side in the detected compressor starts to increase.

  For example, when the vehicle is accelerated, the pressure on the outlet side of the compressor tends to decrease first. However, the pressure on the outlet side does not decrease at a certain point and starts to increase. Such a point at which the pressure on the outlet side of the compressor starts to increase can be considered as a point where the state changes from the state where the supercharging delay is likely to occur to the state where it is difficult to occur.

  In this mode, when the change in the pressure on the outlet side of the compressor starts to increase, the control of the opening degree control means by the adjusting means is stopped, so that it becomes variable when the supercharging delay hardly occurs. Control over the vane opening of the diffuser is returned to control based on predetermined information. Therefore, the original function of a compressor with a variable diffuser can be exhibited very efficiently.

  In another aspect of the supercharger control device of the present invention, bypass means for flowing air into the internal combustion engine without passing through the compressor, and bypass switching means for switching whether or not air is allowed to flow by the bypass means; The adjusting means is configured to allow air to flow in by the bypass means when the acceleration is detected and the pressure on the outlet side is detected to be lower than the pressure on the inlet side. Controls Pibus switching means.

  According to this aspect, for example, by providing bypass means such as a bypass pipe, it is possible to allow air to flow into the internal combustion engine without using a compressor. For example, bypass switching means such as a switching valve is provided in the bypass means, and it is possible to switch whether or not air is allowed to flow in by the bypass means.

  Here, particularly in this embodiment, when the acceleration is detected by the acceleration detecting means and the pressure on the outlet side of the compressor detected by the pressure detecting means is lower than the pressure on the inlet side, air is introduced by the bypass means. Thus, the bypass switching means is controlled. That is, when the condition for controlling the opening degree control means by the adjusting means is satisfied, air is introduced into the internal combustion engine by the bypass means without passing through the compressor.

  When the control of the opening degree control means is started by the adjusting means, for example, a certain amount of time may be required until the vane actually operates and the opening degree changes. That is, even if the adjustment means tries to control the opening degree control means, it may take time until the effect actually appears.

  However, in this embodiment, in the case described above, air can be immediately introduced into the internal combustion engine using the bypass means. Accordingly, it is possible to prevent supercharging delay due to a delay in the change in the vane opening. The bypass means can also function as a surge prevention bypass.

  When the first reflux means and the second reflux means can be provided for the above-described aspect, the reflux by the first reflux means is stopped and the reflux by the second reflux means is performed. In the state where the second return means is stopped in the state of being in the state, the control of the bypass switching means by the adjusting means may not be performed. That is, when the adjustment means does not control the opening degree control means, the bypass switching means may not be controlled.

  The effect | action and other gain of this invention are clarified from the form for implementing invention demonstrated below.

It is a schematic diagram showing the whole composition of an engine system. It is a top view which shows the structure of a diffuser. It is a graph which shows the change of the outlet side pressure of the compressor at the time of vehicle acceleration. It is a flowchart which shows operation | movement of the supercharger control apparatus which concerns on 1st Embodiment. It is a flowchart which shows operation | movement of the supercharger control apparatus which concerns on 2nd Embodiment. It is a flowchart which shows operation | movement of the supercharger control apparatus which concerns on 3rd Embodiment. It is a flowchart which shows operation | movement of the supercharger control apparatus which concerns on 4th Embodiment. It is a flowchart which shows operation | movement of the supercharger control apparatus which concerns on 5th Embodiment. It is a graph which shows the timing of the change of the exit side pressure of a compressor, and a vane control change. It is the schematic which shows the whole structure of the engine system with which the supercharger control apparatus which concerns on 6th Embodiment is applied. It is a flowchart which shows operation | movement of the supercharger control apparatus which concerns on 6th Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, the configuration of the entire engine system to which the supercharger control device according to the present embodiment is applied will be described with reference to FIG. FIG. 1 is a schematic diagram showing the overall configuration of the engine system. In FIG. 1, for convenience of explanation, among the elements constituting the engine system, only those closely related to the present embodiment are selectively illustrated, and the other elements are omitted as appropriate.

  In FIG. 1, the engine system according to the present embodiment includes an ECU 100, a compressor 110, a turbine 120, and an engine 200.

  The ECU 100 includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and controls the overall operation of the engine system, as well as the “opening degree control means” and “ It is configured to function as an example of “adjustment means”.

  The compressor 110 compresses the air that has flowed in and supplies the compressed air downstream. Although not shown here, the compressor 110 is provided with a variable diffuser. The configuration of the variable diffuser will be described in detail later.

  Turbine 120 rotates using exhaust gas supplied from engine 200 through exhaust pipe 116 as power. The turbine 110 is connected to the compressor 120 via a shaft, and is configured to be able to rotate integrally with each other. That is, the turbine 120 and the compressor 110 constitute a turbocharger that is an example of a “supercharger” according to the present invention.

  The engine 200 is a gasoline engine that is a power source of a vehicle such as an automobile, and is an example of the “internal combustion engine” according to the present invention.

  The engine 200 is an in-line four-cylinder gasoline engine in which four cylinders 201 are arranged in series in a cylinder block. Although not shown in detail here, the engine 200 performs the reciprocating motion of the piston that occurs when the air-fuel mixture burns inside each cylinder 201 via the connecting rod. It can be converted into a rotational motion. The engine 200 is provided with an engine rotation speed detection unit 210 for detecting the rotation speed of the engine 200. The engine speed detection unit 210 is an example of the “acceleration detection means” in the present invention, and is configured to be able to transmit the detected engine speed to the ECU 100.

  In the combustion chamber in the cylinder 201 of the engine 200, an air-fuel mixture formed by mixing air supplied through the intake pipe 114 and fuel injected and supplied from the injector at the intake port communicating with the intake pipe 114 is sucked. Is done.

  An air cleaner 101, an intake control valve 103, a compressor 110, air flow meters 112a and 112b, an intercooler 113, and a throttle valve 115 are provided on the intake side of the engine 200 (that is, upstream of the cylinder 201).

The air cleaner 101 purifies air sucked from the outside and supplies the air to the compressor 110 via the intake pipe 102. The air flow meter 112 a is provided on the inlet side of the compressor 110 and detects the amount of air flowing through the intake pipe 102. The air flow meter 112b is provided on the outlet side of the compressor and detects the amount of air flowing through the intake pipe 111. The amount of air detected in the air flow meters 112a and 112b is converted into pressure in the intake pipes 102 and 111 in the ECU 100, respectively. That is, the air flow meters 112a and 112b are an example of the “pressure detection means” in the present invention.

  The intercooler 113 is configured to be able to cool intake air and increase the supercharging efficiency of the air. A throttle valve 115 is installed downstream of the intercooler 113. The throttle valve 115 is an electronically controlled valve, and is configured such that its opening / closing operation is controlled by a throttle valve motor (not shown).

  The throttle valve motor is electrically connected to the ECU 100, and the driving force is controlled by the ECU 100. The ECU 100 controls the opening / closing state of the throttle valve 115 by controlling the driving of the throttle valve motor in accordance with, for example, the accelerator opening, the vehicle speed, or the rotational speed of the engine 200.

  The air-fuel mixture introduced into the cylinder 201 from the intake side is ignited by an ignition operation by an ignition device (not shown), and an explosion process is performed in the cylinder 201. When the explosion process is performed, the burned air-fuel mixture (including a partially unburned air-fuel mixture) is discharged to an exhaust port (not shown) in the exhaust process following the explosion process. The exhaust discharged to the exhaust port is guided to the exhaust pipe 116.

  An HPLEGR pipe 117, an HPLEGR control valve 118, a turbine 120, a three-way catalyst 122, an LPLEGR pipe 123, and an LPLEGR control valve 124 are provided on the exhaust side of the engine 200 (that is, downstream of the cylinder 201). It has been.

  The HPLEGR pipe 117 can recirculate the exhaust in the exhaust pipe 116 discharged from the engine 200 to the intake pipe 114 on the intake side of the engine 200. The HPLEGR pipe 117 is provided with an HPLEGR control valve 118 so that the amount of EGR gas can be adjusted. The HPLEGR control valve 118 is an electromagnetic open / close valve that can take, for example, a fully open and fully closed binary open / close state, and is electrically connected to the ECU 100 so that the open / close state is controlled by the ECU 100. ing. The HPLEGR pipe 117 and the HPLEGR control valve 118 are examples of the “first reflux unit” according to the present invention.

The three-way catalyst 122 is provided on the exhaust pipe 121 and purifies HC (hydrocarbon), CO ₂ (carbon dioxide), and NOx (nitrogen oxide) contained in the exhaust gas that has passed through the turbine 120.

  The LPLEGR pipe 123 can recirculate the exhaust gas downstream of the three-way catalyst 122 to the intake pipe 102 on the inlet side of the compressor 110. The LPLEGR pipe 123 is provided with an LPLEGR control valve 124 so that the amount of EGR gas can be adjusted. Like the HPLEGR control valve 118, the LPLEGR control valve 124 is an electromagnetic on-off valve that can take a binary open / close state, for example, fully open and fully closed. The ECU 100 is configured to be controlled. The LPLEGR pipe 123 and the LPLEGR control valve 124 are an example of the “second return means” according to the present invention.

  Next, the configuration of the diffuser attached to the compressor will be specifically described with reference to FIG. FIG. 2 is a plan view showing the configuration of the diffuser.

  In FIG. 2, the diffuser 300 includes a vane 330 attached to a base plate 310 via a rotation shaft 320.

  The rotation shafts 320 are arranged concentrically with the base plate 310 at an angular interval, and are configured to be rotatable through the base plate 310. The rotation shaft 320 is driven and rotated by, for example, an actuator (not shown). Thereby, the angle of the vane 330 attached to the rotating shaft 320 changes.

  A compressor impeller 350 connected to the turbine impeller via a shaft 340 is disposed in the center of the diffuser 300.

  Next, a change in pressure on the outlet side of the compressor when the vehicle suddenly accelerates will be described with reference to FIG. FIG. 3 is a graph showing changes in the outlet side pressure of the compressor during vehicle acceleration.

  In FIG. 3, the pressure in the exhaust pipe 111 provided on the outlet side of the compressor 110 tends to temporarily decrease from the acceleration timing of the vehicle (that is, time t1 in the figure). In particular, the smaller the angle of the vane 330 (see FIG. 2) in the diffuser 300, the greater the pressure on the outlet side of the compressor 110 decreases. For example, in the graph corresponding to the small vane angle in the figure, the outlet pressure immediately after acceleration is large and negative.

  The reason why the decrease in the outlet side pressure immediately after the acceleration becomes large is considered that the vane 330 in the diffuser 300 becomes a resistance against the air that is about to flow into the compressor 110. Such a decrease in pressure causes a supercharging delay. The supercharging delay may cause deterioration of, for example, emission, fuel consumption, and drivability.

  The supercharger control device according to this embodiment is characterized in that control is performed to increase the vane opening degree under a predetermined condition in order to prevent such a supercharging delay. Below, operation | movement of the supercharger control apparatus which concerns on this embodiment is given and demonstrated with several embodiment.

<First Embodiment>
First, the operation of the supercharger control device according to the first embodiment will be described with reference to FIG. FIG. 4 is a flowchart showing the operation of the supercharger control device according to the first embodiment.

  In FIG. 4, the supercharger control device according to the first embodiment first normally controls the vane 330 in the diffuser 300 based on predetermined information set in advance (step S11). That is, for example, the angle of the vane 330 is controlled based on a value set so as to increase the driving efficiency in accordance with the normal traveling of the vehicle.

  When the vane 330 is normally controlled, acceleration of the vehicle is detected (step S12). Specifically, the acceleration of the vehicle is detected based on the engine speed detected by the engine speed detection unit 210, the accelerator opening, and the like.

  When acceleration of the vehicle is detected, ECU 100 determines whether or not the acceleration is sudden acceleration (step S13). Here, “rapid acceleration” means a state where the speed of the vehicle is rapidly increased to the extent that the driving efficiency is deteriorated only by controlling the vane 330 normally. If it is determined that the acceleration is not a rapid acceleration (step S13: NO), the control returns to the normal control of the vane 330 again.

  On the other hand, if it is determined that the acceleration is sudden acceleration (step S13: YES), the pressures P1 and P2 of the intake pipe 102 are detected from the air amounts detected by the air flow meters 112a and 112b ( Step S14). The pressure may be directly detected by a pressure gauge or the like without using the air flow meters 112a and 112b.

  When the pressures P1 and P2 are detected, it is determined whether or not P2 is smaller than P1 (step S15). That is, it is determined whether or not the pressure on the outlet side of the compressor 110 is lower than the pressure on the inlet side. If it is determined that P2 is larger than P1 (step S15: NO), the control returns to the normal control of the vane 330 again.

  On the other hand, when it is determined that P2 is smaller than P1 (step S15: YES), the opening degree of the vane 330 is made larger than that during normal control by the ECU 100 (step S16). At this time, the angle of the vane 330 may be a predetermined angle or may be fully opened by turning off the operation of the variable diffuser.

  By increasing the opening degree of the vane 330, it is possible to prevent the vane 330 from becoming a resistance to the air that is about to flow into the compressor 110. Therefore, it is possible to prevent the pressure on the outlet side in the compressor 110 from temporarily becoming negative as shown in FIG. Therefore, it is possible to effectively prevent the supercharging delay.

  As described above, according to the supercharger control device according to the first embodiment, the operation efficiency of the supercharger can be extremely effectively increased.

Second Embodiment
Next, the operation of the supercharger control device according to the second embodiment will be described with reference to FIG. FIG. 5 is a flowchart showing the operation of the supercharger control device according to the second embodiment. The second embodiment is different from the first embodiment described above in that the state of the EGR system is detected, and other configurations and operations are generally the same. Therefore, in the second embodiment, portions different from those in the first embodiment will be described in detail, and descriptions of overlapping portions will be omitted as appropriate.

  In FIG. 5, the supercharger control device according to the second embodiment first normally controls the vane 330 in the diffuser 300 based on predetermined information set in advance (step S21). That is, for example, the angle of the vane 330 is controlled based on a value set so that driving efficiency is increased in accordance with the normal traveling of the vehicle.

  Here, particularly in the second embodiment, the operating state of the EGR system is detected (step S22). Specifically, a state in which only the reflux by the HPLEGR pipe 117 is performed (hereinafter referred to as “HPL state” as appropriate), a state in which only the reflux by the LPLEGR pipe 123 is performed (hereinafter referred to as “LPL state” as appropriate). Or an operating state in which refluxing is performed by both the HPLEGR pipe 117 and the LPLEGR pipe 123 (hereinafter, referred to as “MPL state” as appropriate).

  Thereafter, as in the first embodiment described above, acceleration of the vehicle is detected (step S23), it is determined whether or not the acceleration is sudden acceleration (step S24), and the pressure P1 on the inlet side of the compressor 110 and The outlet side pressure P2 is detected (step S25), and it is determined whether or not P2 is smaller than P1 (step S26).

  Here, in the second embodiment, it is determined whether or not the operating state of the EGR system detected in step 23 is the LPL state (step S27). If it is determined that the operating state of the EGR system is the LPL state (step S27: YES), the ECU 100 increases the opening degree of the vane 330 compared to that during normal control (step S28). On the other hand, when it is determined that the operation state of the EGR system is not the LPL state (step S27: NO), the control returns to the normal control of the vane 330 again. That is, when the operation state of the EGR system is the HPL state or the MPL state, the vane 330 is kept in the normal control.

  When the EGR system is in the LPL state, the HPLEGR that recirculates the exhaust gas to the outlet side of the compressor 110 is stopped. Therefore, even if the LPLEGR is stopped, the pressure on the outlet side of the compressor 110 greatly decreases. There is no end to it. Therefore, it is considered that the possibility of the supercharging delay occurring is lower than that in the case of the HPL state or the MPL state.

  More specifically, when the state that is in the LPL state is a state in which no recirculation is performed by the EGR system (hereinafter, referred to as “less EGR state” as appropriate), if the HPL state becomes the less EGR state, the HPL When the state becomes the LPL state, the MPL state becomes the less EGR state, the MPL state becomes the HPL state, or the MPL state becomes the LPL state, the possibility of occurrence of a supercharging delay is low.

  Therefore, if the control for increasing the opening degree of the vane 330 is not performed, the vane 330 is normally controlled, and the function as a compressor with a variable diffuser can be efficiently exhibited.

  As described above, according to the supercharger control device according to the second embodiment, the supercharger can be controlled more appropriately by taking into account the operating state of the EGR system as a condition for controlling the vane 330. Is possible.

<Third Embodiment>
Next, the operation of the supercharger control device according to the third embodiment will be described with reference to FIG. FIG. 6 is a flowchart showing the operation of the supercharger control device according to the third embodiment. The third embodiment is different from the above-described embodiments in that the vane control is returned to normal under a certain condition, and other configurations and operations are substantially the same. For this reason, in 3rd Embodiment, a different part from each embodiment mentioned above is demonstrated in detail, and description is abbreviate | omitted suitably about the overlapping part.

  In FIG. 6, the supercharger control device according to the third embodiment, as described in the first and second embodiments described above, when the opening of the vane 330 is made larger than the normal control (step S31: YES), the time elapsed from the time when the opening of the vane 330 is increased is counted (step S32). If it is determined that the elapsed time has reached the predetermined period (step S33: YES), the opening degree of the vane 330 is returned to the normal control (step S34).

  When the opening degree of the vane 330 is increased during acceleration, the supercharging delay can be effectively prevented as described above, but on the other hand, the opening degree of the vane 330 is continuously increased even when the supercharging delay hardly occurs. If so, the original function of the compressor 110 with the variable diffuser is diminished. That is, it is difficult to obtain the aperture effect by the diffuser 300.

  On the other hand, if the vane 330 is normally controlled after the lapse of a predetermined period, the original function of the compressor with the variable diffuser can be exhibited very efficiently when the supercharging delay is unlikely to occur. Can do.

  As described above, according to the supercharger control device according to the third embodiment, it is possible to control the supercharger more suitably.

<Fourth embodiment>
Next, the operation of the supercharger control device according to the fourth embodiment will be described with reference to FIG. FIG. 7 is a flowchart showing the operation of the supercharger control device according to the fourth embodiment. The fourth embodiment differs from the third embodiment described above in terms of conditions for returning the vane control to normal, and the other configurations and operations are generally the same. Therefore, in the fourth embodiment, portions different from the third embodiment will be described in detail, and descriptions of overlapping portions will be omitted as appropriate.

  In FIG. 7, as described in the first and second embodiments described above, the supercharger control device according to the fourth embodiment is configured such that the opening degree of the vane 330 is larger than the normal control (step S41: YES), the pressure P2 in the intake pipe 111 on the outlet side of the compressor 110 is detected (step S42). When it is determined that the difference between the pressure P2 and the reference pressure is within the predetermined range (step S43: YES), the opening degree of the vane 330 is returned to the normal control (step S54). The difference between the pressure P2 and the reference pressure is monitored, for example, by comparing the pre-mapped reference pressure with the detected pressure P2.

  As described above, if the opening degree of the vane 330 is kept large during acceleration, the original function of the compressor 110 with the variable diffuser may be lost. On the other hand, if the vane 330 is normally controlled when the pressure P2 deviation is reduced to a certain extent, when the supercharging delay is unlikely to occur, the original function of the compressor with the variable diffuser is restored. It can be exhibited very efficiently.

  As described above, according to the supercharger control device according to the fourth embodiment, it is possible to control the supercharger more suitably.

<Fifth Embodiment>
Next, operation | movement of the supercharger control apparatus which concerns on 5th Embodiment is demonstrated with reference to FIG.8 and FIG.9. FIG. 8 is a flowchart showing the operation of the supercharger control device according to the fifth embodiment, and FIG. 9 is a graph showing the change of the outlet side pressure of the compressor and the timing of the vane control change. The fifth embodiment is different from the third and fourth embodiments described above in terms of conditions for returning the vane control to normal, and the other configurations and operations are generally the same. Therefore, in the fifth embodiment, portions different from those in the third and fourth embodiments will be described in detail, and descriptions of overlapping portions will be omitted as appropriate.

  In FIG. 8, as explained in the first and second embodiments described above, the supercharger control device according to the fifth embodiment is configured such that the opening degree of the vane 330 is larger than that in the normal control (step S51: YES), the pressure P2 in the intake pipe 111 on the outlet side of the compressor 110 is detected (step S52). When it is determined that the change in the pressure P2 has become positive (that is, the pressure P2 has started to increase) (step S53: YES), the opening degree of the vane 330 is returned to the normal control (step S54). .

  As shown in FIG. 9, specifically, the opening degree of the vane 330 is returned to the normal control at time t <b> 2 when the pressure of P <b> 2 is lowest and starts to increase.

  As described above, if the opening degree of the vane 330 is kept large during acceleration, the original function of the compressor 110 with the variable diffuser may be lost. On the other hand, if the vane 330 is normally controlled when the pressure P2 begins to increase, the original function of the compressor with the variable diffuser is extremely efficient when the supercharging delay hardly occurs. Can be demonstrated.

  As described above, according to the supercharger control device according to the fifth embodiment, it is possible to control the supercharger more suitably.

<Sixth Embodiment>
Next, the operation of the supercharger control device according to the sixth embodiment will be described with reference to FIGS. 10 and 11. FIG. 10 is a schematic diagram showing an overall configuration of an engine system to which the supercharger control device according to the sixth embodiment is applied, and FIG. 11 is an operation of the supercharger control device according to the sixth embodiment. It is a flowchart which shows. In FIG. 10, the illustration of the ECU 100 and the air flow meters 112a and 112b shown in FIG. 1 is omitted for convenience of explanation. Further, the sixth embodiment differs from the second embodiment described above in that it includes a compressor bypass, and is otherwise substantially the same. Therefore, in the sixth embodiment, portions different from the second embodiment will be described in detail, and descriptions of overlapping portions will be omitted as appropriate.

  10, the engine system to which the control device according to the sixth embodiment is applied includes a compressor bypass pipe 400 and a compressor bypass control valve 410 in addition to the configuration shown in FIG.

  The compressor bypass pipe 400 is an example of the “bypass means” in the present invention, and is provided so as to connect the intake pipe 102 upstream of the compressor 110 and the intake pipe 111 downstream of the compressor 110 to each other. For this reason, it is possible to let air flow into the engine 200 without passing through the compressor 110.

  The compressor bypass control valve 410 is an example of the “bypass switching means” in the present invention, and is provided on the compressor bypass pipe 400. The compressor bypass control valve 410 is an electromagnetic on / off valve that can take, for example, a fully open and fully closed binary open / close state, and is electrically connected to the ECU 100 so that the open / close state is controlled by the ECU 100. It has become. By switching the open / close state of the compressor bypass control valve 410, it is possible to switch whether or not air is introduced through the compressor bypass pipe 400.

  In FIG. 11, in the supercharger control device according to the sixth embodiment, first, the same processes as in step 21 to step 28 in the second embodiment are performed (step S61 to step S68), and the opening degree of the vane 330 is normal. It is controlled to be larger than at the time of control. Note that while the normal control is being performed on the vane 330, the inflow of air through the compressor bypass pipe 400 is not performed. That is, the compressor bypass control valve 410 is closed.

  When the opening degree of the vane 330 is increased, the compressor bypass control valve 410 is opened, and air is introduced through the compressor bypass pipe 400 (step S69). Therefore, the air taken into the engine system can flow into the engine 200 without passing through the compressor 110.

  Even if the control is started so as to increase the opening degree of the vane 330 in step S68, a certain amount of time may be required until the vane 330 actually operates and the opening degree changes. In other words, due to a hardware problem in the vane 330, it may take time to obtain the effect of increasing the opening of the vane 330.

  On the other hand, when the opening degree of the vane 330 is increased, if the air is introduced using the compressor bypass pipe 400, the air can be immediately introduced into the engine 200 without passing through the compressor 110. Therefore, it is possible to prevent a supercharging delay due to a delay in the change in the opening degree of the vane 330. The compressor bypass pipe 400 can also function as a surge prevention bypass.

  As described above, according to the supercharger control device according to the sixth embodiment, it is possible to control the supercharger more suitably.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. The apparatus is also included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 100 ... ECU, 101 ... Air cleaner, 110 ... Compressor, 112a, 112b ... Air flow meter, 113 ... Intercooler, 117 ... HPLEGR pipe, 118 ... HPLEGR control valve, 120 ... Turbine, 122 ... Three-way catalyst, 123 ... LPLEGR pipe, 124 ... LPLEGR control valve, 200 ... engine, 201 ... cylinder, 210 ... engine speed detector, 300 ... diffuser, 330 ... vane, 350 ... compressor impeller, 400 ... compressor bypass pipe, 410 ... compressor bypass control valve

Claims (7)

A supercharger control device mounted on a vehicle comprising an internal combustion engine and a supercharger having a compressor and a turbine with a variable diffuser,
Opening control means for controlling the vane opening of the variable diffuser based on predetermined information;
Acceleration detection means for detecting acceleration of the vehicle;
Pressure detecting means for detecting the pressure on the inlet side and the pressure on the outlet side in the compressor;
When the acceleration is detected and it is detected that the pressure on the outlet side is lower than the pressure on the inlet side, the vane opening of the variable diffuser is set to be larger than a value based on the predetermined information. And a regulating means for controlling the opening degree controlling means. Recirculation means for recirculating exhaust gas from the exhaust side to the intake side of the internal combustion engine;
The supercharger control device according to claim 1, further comprising a recirculation control unit that stops recirculation of the exhaust gas by the recirculation unit when the acceleration is detected. The recirculation unit includes a first recirculation unit that recirculates the exhaust gas between the internal combustion engine and the turbine between the compressor and the internal combustion engine, and a first recirculation unit that recirculates the exhaust gas from the turbine outlet side to the compressor inlet side. 2 reflux means,
When the second reflux unit is stopped in a state where the reflux by the first reflux unit is stopped and the reflux by the second reflux unit is performed, the adjustment unit The supercharger control device according to claim 2, wherein the control means is not controlled.   The said adjustment means stops the control of the said opening degree control means after progress for a predetermined period, after starting control of the said opening degree control means, The Claim 1 characterized by the above-mentioned. Supercharger control device.   The adjusting means stops the control of the opening degree control means when a deviation between the outlet side pressure and a reference pressure set as a reference of the outlet side pressure is within a predetermined range. The supercharger control device according to any one of claims 1 to 4.   The supercharging according to any one of claims 1 to 5, wherein the adjustment unit stops the control of the opening degree control unit when a change in the pressure on the outlet side starts to increase. Controller. Bypass means for flowing air into the internal combustion engine without going through the compressor;
A bypass switching means for switching whether to allow air to flow in or not by the bypass means,
When the acceleration is detected and it is detected that the pressure on the outlet side is lower than the pressure on the inlet side, the adjusting means controls the bypass switching means so that air is introduced by the bypass means. It controls. The supercharger control apparatus as described in any one of Claim 1 to 6 characterized by the above-mentioned.

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