JP5817510B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine, and more particularly, to a control device for an internal combustion engine that performs calculations using a multi-core processor having a plurality of cores.

  Conventionally, as disclosed in, for example, Japanese Patent Laid-Open No. 2008-269487, in an electronic control device for engine control including a microcomputer adopting at least one of a multi-core configuration and a cache memory mounting configuration, power consumption during engine stop Techniques for reducing the above are disclosed. Both the CPU core and the cache memory are elements with high power consumption in the microcomputer. Therefore, in the above-described conventional technology, a mode is selected in which the CPU core and the cache memory are fully used while the engine is operating and the highest processing capacity is exhibited. A mode for reducing the amount of cache memory used compared to when the engine is operating is selected.

JP 2008-269487 A JP 2008-291626 A JP 2010-203426 A JP-A-4-41931

  By the way, in model-based control of an internal combustion engine using a control model in recent years, it is possible to speed up computation by performing parallel computation processing using a multi-core processor having a plurality of cores. However, as the number of cores used increases, the calculation load increases, and power consumption tends to increase accordingly. For this reason, from the viewpoint of reducing power consumption, it is preferable to perform efficient calculation resource allocation according to the calculation load. In this regard, in the above-described conventional apparatus, no consideration is given to the calculation resource allocation during the engine operation, and there is still room for improvement.

  The present invention has been made to solve the above-described problems, and in an internal combustion engine that performs arithmetic processing using a multi-core processor having a plurality of cores, an efficient use core according to the arithmetic load of the internal combustion engine It is an object of the present invention to provide a control device for an internal combustion engine capable of performing distribution.

In order to achieve the above object, a first invention provides a supercharger disposed in an intake passage, an intake bypass passage that bypasses a downstream side and an upstream side of the supercharger in the intake passage, and the intake air An air bypass valve for opening and closing a bypass passage, and a control device for an internal combustion engine that operates the air bypass valve in accordance with an operating state of the internal combustion engine,
An arithmetic means having a multi-core processor equipped with a plurality of cores, assigning various arithmetic tasks related to the operation of the internal combustion engine to the plurality of cores, and performing arithmetic operations in parallel,
Control means for reducing the number of cores used for the computing means when the air bypass valve is fully opened, compared to before being fully opened;
Equipped with a,
The calculation means includes assignment means for assigning a calculation task related to a supercharging operation by the supercharger to one or a plurality of designated cores designated from the plurality of cores,
The control means stops the designated core when the air bypass valve is fully opened .

According to a second invention, in the first invention,
The control means is characterized in that when the air bypass valve is actuated from the fully open direction to the close direction, the number of cores used for the computing means is increased as compared to before the actuating means.

According to a third invention, in the first or second invention,
The calculating means includes model calculating means for performing a supercharging prediction calculation using a supercharging model of the internal combustion engine,
The assigning means assigns a supercharging prediction calculation in the model calculating means to the designated core.

A fourth invention is any one of the first to third inventions,
Predicting means for predicting operating conditions to be achieved in the future of the internal combustion engine,
The control means is characterized in that when the operating condition predicted by the prediction means is a condition that the air bypass valve is fully opened, the number of cores used in the calculation means is reduced.

A fifth invention is the fourth invention,
The predicting means performs delay control for delaying the change in the actual throttle opening with respect to the change in the target throttle opening calculated from the accelerator opening, and determines the in-cylinder air amount to be achieved in the future from the target throttle opening. It is characterized by prediction.

According to the first invention, when the air bypass valve is fully opened, the number of cores used is reduced as compared with that before the fully open operation. When the air bypass valve is fully opened, the space upstream and downstream of the compressor can be regarded as one space, so the order of the model equation to be solved is It decreases compared with. For this reason, according to the present invention, the number of used cores can be reduced according to the reduction of the calculation load, so that efficient use core distribution according to the calculation load of the internal combustion engine can be performed.
According to the present invention, a calculation task related to the supercharging operation by the supercharger is assigned to one or a plurality of designated cores. When the air bypass valve is fully opened, the use of the designated core is stopped. For this reason, according to the present invention, it is possible to effectively stop computations that are not required when the air bypass valve is fully opened, and to perform efficient use core distribution according to the computation load of the internal combustion engine.

  According to the second aspect of the invention, when the air bypass valve is operated from the fully open direction to the closed direction, the number of cores used is increased as compared to before the operation. For this reason, according to the present invention, the number of used cores can be increased in accordance with the increase in the model order to be solved, so that it is possible to efficiently allocate the used cores in accordance with the calculation load of the internal combustion engine. .

According to the third invention, when the supercharging prediction calculation task using the supercharging model is assigned to the designated core and the air bypass valve is fully opened, the use of the designated core is stopped. For this reason, according to the present invention, it is possible to efficiently stop the supercharging prediction calculation of the supercharging model which becomes unnecessary when the air bypass valve is fully opened, and to effectively allocate the calculation resources as the entire apparatus.

According to the fourth invention, the operating condition to be achieved in the future of the internal combustion engine is predicted, and when the predicted operating condition is a condition in which the air bypass valve is fully opened, the core used for the calculation means The number is reduced. Therefore, according to the present invention, since the number of used cores can be reduced by predicting in advance that the air bypass valve is fully opened, efficient use core allocation according to the future calculation load is performed in advance. Can be performed.

According to the fifth aspect of the present invention, the cylinder air amount that will be achieved in the future can be predicted by performing the delay control of the throttle. Therefore, the operation of the air bypass valve is determined in advance from the predicted cylinder air amount. It becomes possible to grasp.

It is a figure for demonstrating schematic structure of the internal combustion engine system as embodiment of this invention. It is a flowchart of the routine performed in Embodiment 1 of the present invention. It is a flowchart of the routine performed in Embodiment 2 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted. The present invention is not limited to the following embodiments.

Embodiment 1 FIG.
[Configuration of Embodiment 1]
FIG. 1 is a diagram for explaining a schematic configuration of an internal combustion engine system as an embodiment of the present invention. As shown in FIG. 1, the system according to the present embodiment includes an internal combustion engine 10. The internal combustion engine 10 is a spark ignition type 4-stroke reciprocating engine, which is mounted on a vehicle and used as a power source. An intake passage 12 is connected to the intake side of the internal combustion engine 10. An air cleaner 14 is provided near the inlet of the intake passage 12. An exhaust passage 16 is connected to the exhaust side of the internal combustion engine 10. A post-treatment device 18 for purifying exhaust gas is provided in the middle of the exhaust passage 16.

  The internal combustion engine 10 of the present embodiment includes a turbocharger 20. The turbocharger 20 includes a turbine 20a that is operated by exhaust energy of exhaust gas, and a compressor 20b that is integrally connected to the turbine 20a and that is rotationally driven by exhaust energy of exhaust gas input to the turbine 20a. ing.

  The turbine 20 a and the compressor 20 b of the turbocharger 20 are respectively disposed in the exhaust passage 16 and the intake passage 12. An intercooler 22 and an electronically controlled throttle valve 24 are arranged in this order further downstream of the compressor 20b in the intake passage 12. The air sucked through the air cleaner 14 is compressed by the compressor 20 b of the turbocharger 20 and then cooled by the intercooler 22. The intake air that has passed through the intercooler 22 is distributed to an intake port (not shown) of each cylinder by an intake manifold.

  One end of an intake bypass passage 26 is connected to the intake passage 12 extending from the compressor 20b to the intercooler 22. The other end of the intake bypass passage 26 is connected to the intake passage 12 extending from the air cleaner 14 to the compressor 20b. An air bypass valve (hereinafter simply referred to as “ABV”) 28 for controlling the flow rate of air flowing through the intake bypass passage 26 is disposed in the intake bypass passage 26. By operating the ABV 28 to open the intake bypass passage 26, a part of the air compressed by the compressor 20b is returned again to the inlet side of the compressor 20b. When the turbocharger is in an operating state in which a surge is likely to occur, the surge can be prevented by returning a part of the air exiting the compressor 20b to the inlet side of the compressor 20b through the intake bypass passage 26.

  In addition, the system of the present embodiment is provided with an exhaust bypass passage 30 that bypasses the turbine 20a in the exhaust passage 16 for the purpose of supplying a stable supercharging pressure and protecting the turbocharger 20. A waste gate valve (hereinafter simply referred to as “WGV”) 32 for controlling the flow rate of the exhaust gas flowing through the exhaust bypass passage 30 is disposed in the middle of the exhaust bypass passage 30. By controlling the opening / closing of the WGV 32 according to the operating state of the internal combustion engine 10, the flow rate at which the exhaust gas passes through the exhaust bypass passage 32 is determined.

  The system according to the present embodiment includes an ECU (Electronic Control Unit) 50 as shown in FIG. The ECU 50 is configured as a multi-core ECU having a processor on which n cores (core_1 to core_n) are mounted, and can be used / stopped for each core. In addition to the ABV 28 described above, the input portion of the ECU 50 includes an internal combustion engine such as an accelerator position sensor for detecting the amount of depression of the accelerator pedal (accelerator opening), a crank angle sensor for detecting the crank angle of the internal combustion engine 10, and the like. Various sensors for controlling 10 are connected. In addition to the throttle valve 24, ABV 28, and WGV 32 described above, various actuators for controlling the internal combustion engine 10 are connected to the output portion of the ECU 50. The ECU 50 executes a predetermined control algorithm for driving various actuators based on the various types of input information.

[Characteristic operation of the first embodiment]
Next, the characteristic operation of the first embodiment will be described. The internal combustion engine 10 according to the present embodiment includes various actuators for controlling the internal combustion engine 10 such as a throttle valve 24, ABV 28, and WGV 32 as actuators for controlling the operation thereof. The control device according to the present embodiment controls the internal combustion engine by so-called model-based control. The control state is estimated by frequently using model prediction, and the control amounts of the various actuators described above are determined.

  As model-based control executed in the system of the present embodiment, for example, there is a supercharging prediction calculation using a supercharging model of the turbocharger 20. Specifically, the supercharging model calculates the output (for example, intake pipe pressure, intake air temperature) caused by supercharging by calculating the rotational dynamics of the compressor 20b of the turbocharger 20 and the volume dynamics of the intercooler 22. Etc.). In addition, since many literatures are already well-known about the model structure of a supercharging model, the detailed description is abbreviate | omitted.

  In the system of the present embodiment including a multi-core ECU, the model-based control is executed in one or a plurality of designated cores selected from a plurality of cores. The designated core is a core selected as a core dedicated to performing the supercharging prediction calculation, and is set to the number of cores that can effectively use the calculation resources in consideration of the core usage status of the system. It is preferable. When performing parallel calculation processing using a plurality of designated cores, for example, a known parallel compiler such as OSCAR (Optimally Scheduled Advanced Multiprocessor) is used to divide the supercharge prediction calculation algorithm of the supercharge model, Assign tasks to each designated core. As described above, when parallel calculation processing is performed, the calculation load is effectively reduced as compared with the case of performing sequential calculation processing with a single core.

  Here, in the model-based control described above, when the ABV 28 is fully opened, the space before and after the compressor 20b communicates via the intake bypass passage 26, so this space can be regarded as one space. Therefore, when the ABV 28 is fully opened, there is no need to solve the supercharging prediction calculation of the supercharging model such as the calculation of the rotation dynamics of the compressor 20b and the volume dynamics of the intercooler 22. Therefore, in such a period, there is no particular problem even if the above calculation is stopped. Rather, it is preferable to stop these calculations from the viewpoint of reducing the calculation load.

  Therefore, in the system according to the present embodiment, the number of cores used for calculation is reduced during the period when the ABV 28 is fully opened. Specifically, the supercharging prediction calculation task of the supercharging model described above is assigned to one or a plurality of designated cores designated from among a plurality of cores, and the period during which the ABV 28 is fully opened is The designated core to which the supercharging prediction calculation of the supercharging model is assigned is stopped. As a result, the core on which unnecessary calculations are performed can be effectively stopped, and the calculation load can be reduced as a whole system by effectively allocating the remaining calculation resources. Thereby, it is possible to avoid the task omission and to control the internal combustion engine with high accuracy.

  Further, in the system according to the present embodiment, when the ABV 28 is operated in the closing direction from the fully open state, the calculation in the stopped core is restarted. Thereby, the increase in the calculation load accompanying the start of the supercharging prediction calculation of the supercharging model can be effectively compensated by increasing the number of used cores.

[Specific Processing in Embodiment 1]
Next, with reference to FIG. 2, the specific content of the process performed in this Embodiment is demonstrated. FIG. 2 is a flowchart of a routine in which the ECU 50 increases or decreases the number of used cores used for calculation. Note that the routine shown in FIG. 2 is repeatedly executed during operation of the internal combustion engine 10. In addition, as a premise for executing the routine shown in FIG. 2, here, one or a plurality of designated cores that perform supercharging prediction calculation of the supercharging model are already selected, and the task of the supercharging prediction calculation is assigned to these designated cores. Assume that it is assigned.

  In the routine shown in FIG. 2, it is first determined whether or not the ABV 28 is fully opened (step 100). As a result, when it is determined that the ABV 28 is fully open, it is determined that the supercharging prediction calculation of the supercharging model is unnecessary, and the process proceeds to the next step, and the supercharging prediction calculation of the supercharging model is assigned. The designated core is stopped (step 102). On the other hand, when it is determined in step 100 that the ABV 28 is not fully opened, the supercharging prediction calculation of the supercharging model is executed by the designated core (step 104).

  As described above, according to the system of the present embodiment, the core to which the supercharging prediction calculation of the supercharging model is assigned is stopped during the period in which the ABV 28 is fully opened. As a result, the core on which unnecessary calculations are performed can be effectively stopped, and the calculation load can be reduced as a whole system by effectively allocating the remaining calculation resources.

  By the way, in the above-described first embodiment, the designated core to which the supercharging prediction calculation of the supercharging model is assigned is stopped during the period in which the ABV 28 is fully opened. It is not limited to the specified core. In other words, during the period when the ABV 28 is fully opened, the calculation load related to the supercharging prediction calculation of the supercharging model is reduced to a small extent. For this reason, one of the cores is stopped during the period when the ABV 28 is fully open, and the task of the stopped core is distributed to the remaining used cores, thereby reducing the number of used cores and responding to the calculation load of the internal combustion engine. It is possible to allocate cores at a high rate.

  Moreover, in Embodiment 1 mentioned above, although the supercharging prediction calculation using a supercharging model was illustrated as a calculation which becomes unnecessary during the period when ABV28 is fully opened, ABV28 is operated fully open. The present invention can also be applied to other model calculations that are unnecessary during the period.

Embodiment 2. FIG.
[Features of Embodiment 2]
Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment can be realized by executing a routine shown in FIG. 3 described later using the system shown in FIG.

  In the system of the first embodiment described above, the number of cores used by the ECU 50 is increased or decreased based on the current opening degree of the ABV 28. However, during the transient operation of the internal combustion engine 10, the increase or decrease in the number of cores used does not keep up with the timing of the opening change of the ABV 28, and calculation problems such as missing tasks occur in the calculation process and unnecessary calculations are continued. It is also assumed.

  Therefore, in the system of the second embodiment, the future in-cylinder air amount and the engine speed are predicted as future operating conditions, for example, 32 ms. Specifically, delay control is performed to delay the change in the actual opening of the throttle valve 24 with respect to the change in the target throttle opening calculated from the accelerator opening, and the in-cylinder air amount that will be achieved in the future is reduced. Predict from the degree. Further, the rotational speed of the crankshaft is calculated using the indicated torque calculated using the operating condition parameters and the total value of the auxiliary machine torque and the friction torque, and the engine speed to be achieved in the future is predicted. Then, with reference to the opening degree information defined in the base map of the ABV 28, when these operating conditions belong to a region corresponding to full opening, the ABV 28 is fully opened according to the operating conditions to be achieved in the future. It can be judged. Therefore, in this case, if the designated core to which the supercharging prediction calculation of the supercharging model is assigned is stopped, the core on which the unnecessary calculation is performed can be effectively stopped. As a result, the remaining computing resources can be effectively distributed, so that the calculation load can be reduced as a whole system, and the control of the internal combustion engine can be realized with high accuracy by avoiding task omission.

  In the system according to the present embodiment, when it is determined that the ABV 28 is operated in the closing direction from the fully open state according to the operating conditions to be achieved in the future, the calculation in the stopped core is restarted. . Thereby, the increase in the calculation load accompanying the start of the supercharging prediction calculation of the supercharging model can be effectively compensated by increasing the number of used cores.

[Specific Processing in Second Embodiment]
Next, with reference to FIG. 3, the specific content of the process performed in this Embodiment is demonstrated. FIG. 3 is a flowchart of a routine in which the ECU 50 increases or decreases the number of used cores used for calculation. Note that the routine shown in FIG. 3 is repeatedly executed during operation of the internal combustion engine 10. In addition, as a premise for executing the routine shown in FIG. 3, here, one or a plurality of designated cores for performing the supercharging prediction calculation of the supercharging model are already selected, and the task of the supercharging prediction calculation is assigned to these designated cores. Assume that it is assigned.

  In the routine shown in FIG. 2, first, the engine speed and the in-cylinder air amount in the future of 32 ms are predicted (step 200). Specifically, the ECU 50 calculates the target throttle opening from the accelerator opening measured by an accelerator opening sensor (not shown), and performs the actual operation of the throttle valve 24 with respect to the change in the target throttle opening. By implementing delay control that delays the change in opening, the cylinder air amount that will be achieved in the future for 32 ms is predicted from the target throttle opening.

Further, the ECU 50 calculates the indicated torque τ and the combined value τf of the friction torque and the auxiliary torque using the parameters of the current operating condition. The friction torque is torque due to mechanical friction of each fitting portion such as friction between the piston and the inner wall of the cylinder, and the auxiliary machine torque is torque due to mechanical friction of the auxiliary machines. The total value τf can be specified using, for example, a map that defines the relationship between the engine operating state and the total value τf. Then, the angular acceleration dω / dt of the crankshaft is calculated by substituting the calculated indicated torque τ and the total value τf of the friction torque and the auxiliary torque into the following equation (1) in accordance with the equation of motion.
I · dω / dt = τ−τf (1)

  Here, I is an inertia moment (inertia) of a member (crankshaft or the like) driven by the combustion of the air-fuel mixture, and is a constant determined based on the hardware configuration of the internal combustion engine 10. Then, the engine speed in the future of 32 ms is calculated using the crankshaft rotational speed ω obtained from the angular acceleration dω / dt.

  Next, it is determined whether or not the ABV 28 is fully opened in the future in 32 ms (step 202). Here, specifically, it is determined whether or not the 32 ms future operating condition predicted in step 200 belongs to the fully open region of ABV 28. As a result, when it is determined that the ABV 28 belongs to the fully open region, it is determined that the supercharging prediction calculation of the supercharging model will be unnecessary in the future, and the process proceeds to the next step, and the supercharging prediction of the supercharging model is determined. The designated core to which the operation is assigned is stopped (step 204). On the other hand, if it is determined in step 202 that the ABV 28 does not belong to the fully open region, the supercharging prediction calculation of the supercharging model is executed by the designated core (step 206).

  As described above, according to the system of the present embodiment, when the ABV 28 is fully opened in the future, the core to which the supercharging prediction calculation of the supercharging model is assigned is stopped. As a result, the core on which unnecessary calculations are performed can be effectively stopped, and the calculation load can be reduced as a whole system by effectively allocating the remaining calculation resources.

  By the way, in the second embodiment described above, when the ABV 28 is fully opened in the future, the designated core to which the supercharging prediction calculation of the supercharging model is assigned is stopped. It is not limited to the designated core. In other words, during the period when the ABV 28 is fully opened, the calculation load related to the supercharging prediction calculation of the supercharging model is reduced to a small extent. For this reason, when ABV28 is operated fully open, one of the cores is stopped, and the task of the stopped core is distributed to the remaining used cores, so that the number of used cores is reduced and the calculation load of the internal combustion engine is met. It becomes possible to allocate cores at a high rate.

  In the second embodiment described above, the in-cylinder air amount and the engine speed are predicted as future operating conditions, and the future opening of the ABV 28 is predicted based on these. The method of predicting the degree is not limited to this. That is, for example, only the future in-cylinder air amount may be used as an operation condition necessary for the prediction, or the future opening degree of the ABV 28 is predicted by a known method using other operation conditions. Also good.

  Moreover, in Embodiment 2 mentioned above, although the supercharging prediction calculation using a supercharging model was illustrated as a calculation which becomes unnecessary during the period when ABV28 is operated fully open, ABV28 is operated fully open. The present invention can also be applied to other model calculations that are unnecessary during the period.

10 Internal combustion engine
12 Intake passage 16 Exhaust passage 20 Turbocharger 20a Turbine 20b Compressor 22 Intercooler 24 Throttle valve 26 Intake bypass passage 28 Air bypass valve (ABV)
50 ECU (Electronic Control Unit)

Claims (5)

An internal combustion engine comprising: a supercharger disposed in the intake passage; an intake bypass passage that bypasses a downstream side and an upstream side of the supercharger in the intake passage; and an air bypass valve that opens and closes the intake bypass passage. A control device for an internal combustion engine that operates the air bypass valve according to an operating state of the engine,
An arithmetic means having a multi-core processor equipped with a plurality of cores, assigning various arithmetic tasks related to the operation of the internal combustion engine to the plurality of cores, and performing arithmetic operations in parallel,
Control means for reducing the number of cores used for the computing means when the air bypass valve is fully opened, compared to before being fully opened;
Equipped with a,
The calculation means includes assignment means for assigning a calculation task related to a supercharging operation by the supercharger to one or a plurality of designated cores designated from the plurality of cores,
The control device for an internal combustion engine, wherein the control means stops the designated core when the air bypass valve is fully opened .   2. The internal combustion engine according to claim 1, wherein when the air bypass valve is operated from a fully open position to a closing direction, the control means increases the number of cores used for the calculation means as compared to before the operation. Control device. The calculating means includes model calculating means for performing a supercharging prediction calculation using a supercharging model of the internal combustion engine,
3. The control apparatus for an internal combustion engine according to claim 1, wherein the allocating unit allocates the supercharging prediction calculation in the model calculating unit to the designated core. Predicting means for predicting operating conditions to be achieved in the future of the internal combustion engine,
The control means reduces the number of cores used for the calculation means when the operation condition predicted by the prediction means is a condition in which the air bypass valve is fully opened. The control apparatus for an internal combustion engine according to any one of claims 3 to 4. The predicting means performs delay control for delaying the change in the actual throttle opening with respect to the change in the target throttle opening calculated from the accelerator opening, and determines the in-cylinder air amount to be achieved in the future from the target throttle opening. 5. The control device for an internal combustion engine according to claim 4 , wherein the control is performed.

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