Vehicle Control Systems

Abstract

To provide a vehicular control system capable of appropriately compensating for a drop in driving force by stop processing.SOLUTION: A vehicular control system is applied to a vehicle mounted with an engine 10 having a plurality of cylinders. The vehicular control system includes ENGECU 70, MGECU 90, and HEVECU 110. The ENGECU 70 executes stop processing for stopping fuel supply to a part of the cylinders and supplying fuel to the remaining cylinders during a load operation of the engine 10. The HEVECU 110 and the ENGECU 70 execute compensation processing for compensating for the output decreased by the execution of the stop processing when the stop processing is executed by increasing the output generated by the combustion in the remaining cylinders. The HEVECU 110 and the ENGECU 70 make the output increased by the compensation processing smaller as the shaft torque in a crank shaft 26 of the engine 10 is larger when comparison is made in the state that the engine speed is the same.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle control system. [Background technology]

[0002] Patent Document 1 discloses a vehicle equipped with an engine having multiple cylinders. The vehicle is provided with an exhaust purification device that purifies exhaust gas discharged from the multiple cylinders. The catalyst of the exhaust purification device exerts its exhaust purification ability at an activation temperature. Therefore, when the catalyst temperature is low, the vehicle control system performs catalyst warm-up to warm the catalyst to its activation temperature.

[0003] The control system disclosed in Patent Document 1 executes a stop process when it is necessary to raise the temperature of the catalyst, stopping the fuel supply to some of the cylinders of the engine while supplying fuel to the remaining cylinders. This causes oxygen to be supplied to the exhaust purification device through the stopped cylinders to which fuel supply has been stopped. This promotes oxidation reactions in the catalyst, raising the temperature of the catalyst. In this way, the control system raises the temperature of the catalyst by executing the stop process to supply oxygen.

[0004] When this stopping process is being performed, fuel supply to the stopped cylinders is stopped, resulting in a power output shortage. Patent Document 1 therefore discloses a method of compensating for the power output shortage by combustion in cylinders other than the stopped cylinders. Specifically, the power output shortage is compensated for by increasing the intake air amount and the amount of fuel supplied to the cylinders other than the stopped cylinders. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-60027 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the amount of power output increased by increasing the amount of fuel supplied to cylinders other than the deactivated cylinders is affected by pumping loss and friction loss. The magnitude of pumping loss and friction loss varies depending on the engine operating state at that time. Therefore, simply determining the amount of fuel supplied to cylinders other than the deactivated cylinders based on the number of deactivated cylinders may not adequately compensate for the increased power output. [Means for solving the problem]

[0007] The means for solving the above problems and their effects will be described below. A vehicle control system for solving the above problem includes a control unit for controlling an engine having a plurality of cylinders. and a filter that captures particulate matter in the exhaust The vehicle control system is applied to a vehicle equipped with the engine. When the amount of particulate matter trapped in the filter is equal to or greater than a regeneration execution value, The vehicle control system executes a stop process for stopping fuel supply to some of the cylinders and supplying fuel to the remaining cylinders, and a compensation process for increasing the output generated by combustion in the remaining cylinders to compensate for the output reduced in the some of the cylinders due to the execution of the stop process while the stop process is being executed. Furthermore, when compared under the same engine speed, the vehicle control system decreases the output increased by the compensation process as the axial torque of the engine crankshaft increases.

[0008] The amount of output power that is reduced by the execution of the stop process, i.e., the amount of output power that must be compensated for, varies depending on the engine speed and the magnitude of the shaft torque. When comparing under the same engine speed, the greater the shaft torque, the smaller the amount of output power that must be compensated for.

[0009] According to the above configuration, the larger the shaft torque is, the smaller the output power increased by the compensation process is, in accordance with this tendency. Therefore, the amount of output power increased by the compensation process can be changed in accordance with changes in the amount of output power that needs to be compensated for. Therefore, the output power can be appropriately compensated for. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a vehicle control system and a vehicle drive system. [Figure 2] FIG. 2 is a flowchart showing a series of steps involved in the shutdown process. [Figure 3] FIG. 3 is a graph illustrating the manner in which the required engine torque and the required engine speed are calculated. [Figure 4] FIG. 4 is a flowchart of the process executed by the vehicle control device. [Figure 5] FIG. 5 is a graph illustrating the shaft torque when the stop process is not being executed. [Figure 6] FIG. 6 is a graph illustrating the shaft torque when the stop process is being executed. [Figure 7] FIG. 7 is a flowchart showing a series of steps involved in the correction coefficient calculation process. [Figure 8] FIG. 8 is an explanatory diagram illustrating map data for calculating the correction coefficient. [Figure 9] FIG. 9 is a flowchart of the process executed by the engine control device. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of a vehicle control system will be described with reference to the drawings. <Hybrid system configuration> As shown in FIG. 1, the hybrid system includes an engine 10, a first motor-generator 52, and a second motor-generator 54 as driving force sources. The engine 10 includes four cylinders #1 to #4. A throttle valve 14 is provided in an intake passage 12 of the engine 10. Air drawn into the intake passage 12 flows into a combustion chamber 18 as an intake valve 16 opens. Fuel is injected into the combustion chamber 18 from an in-cylinder injection valve 22. The air-fuel mixture in the combustion chamber 18 is combusted as a result of spark discharge from an ignition plug 24. The combustion energy generated at this time is converted into rotational energy of a crankshaft 26.

[0012] The air-fuel mixture burned in the combustion chamber 18 is discharged as exhaust gas into an exhaust passage 30 when an exhaust valve 28 opens. A three-way catalyst 32 having oxygen storage capacity and a gasoline particulate filter 34 (hereinafter referred to as GPF 34) are provided in the exhaust passage 30. In this embodiment, the GPF 34 is exemplified by a filter that collects particulate matter (hereinafter referred to as PM) and supports the three-way catalyst.

[0013] The crankshaft 26 is mechanically connected to a carrier C of a planetary gear mechanism 50 that constitutes a power split device. A rotating shaft 52a of a first motor generator 52 is mechanically connected to a sun gear S of the planetary gear mechanism 50. A rotating shaft 54a of a second motor generator 54 and drive wheels 60 are mechanically connected to a ring gear R of the planetary gear mechanism 50. An AC voltage is applied to terminals of the first motor generator 52 by an inverter 56. An AC voltage is applied to terminals of the second motor generator 54 by an inverter 58. The inverters 56 and 58 convert a terminal voltage Vb of a battery 59, which is a DC voltage source, into an AC voltage. In this embodiment, the battery 59 is assumed to be a secondary battery such as a lithium-ion secondary battery.

[0014] <Configuration of vehicle control system> As shown in FIG. 1, the vehicle control system includes an ENGECU 70 which is an engine control device, an MGECU 90 which is a motor control device, and an HEVECU 110 which is a vehicle control device.

[0015] The ENGECU 70 controls the engine 10 mounted on the vehicle. The ENGECU 70 operates operating parts of the engine 10, such as the throttle valve 14, the in-cylinder injection valve 22, and the spark plug 24, in order to control the torque, exhaust component ratio, and other control variables. Fig. 1 shows operation signals MS1 to MS3 for the throttle valve 14, the in-cylinder injection valve 22, and the spark plug 24, respectively.

[0016] In order to control the controlled variable, the ENGECU 70 refers to the intake air amount Ga detected by the air flow meter 80 and the output signal Scr of the crank angle sensor 82. The ENGECU 70 also refers to the water temperature THW detected by the water temperature sensor 88.

[0017] The CPU 72, ROM 74, and peripheral circuit 76 included in the ENGECU 70 are capable of communicating with each other via a communication line 78. Here, the peripheral circuit 76 includes a circuit that generates a clock signal that regulates internal operations, a power supply circuit, a reset circuit, etc. The ENGECU 70 controls the control variables by the CPU 72 executing a program stored in the ROM 74.

[0018] The ENGECU 70 is further capable of communicating with the MGECU 90 and the HEVECU 110 . The MGECU 90 controls the first motor generator 52. The MGECU 90 operates the inverter 56 to control the rotation speed, which is the control variable of the first motor generator 52. The MGECU 90 also controls the second motor generator 54. The MGECU 90 operates the inverter 58 to control the torque, which is the control variable of the second motor generator 54. FIG. 1 shows operation signals MS4 and MS5 of the inverters 56 and 58. The MGECU 90 refers to an output signal Sm1 of a first rotation angle sensor 100 that detects the rotation angle of the first motor generator 52 to control the control variable of the first motor generator 52. The MGECU 90 also refers to an output signal Sm2 of a second rotation angle sensor 102 that detects the rotation angle of the second motor generator 54 to control the control variable of the second motor generator 54.

[0019] The CPU 92, ROM 94, and peripheral circuit 96 included in the MGECU 90 are capable of communicating with each other via a communication line 98. The MGECU 90 controls the control amount by the CPU 92 executing a program stored in the ROM 94.

[0020] The HEV ECU 110 controls the above hybrid system. The HEV ECU 110 outputs command values for the engine 10 to the ENG ECU 70. The HEV ECU 110 outputs command values for the first motor generator 52 and the second motor generator 54 to the MG ECU 90. In order to output command values, the HEV ECU 110 refers to the accelerator operation amount ACCP, which is the amount of depression of the accelerator pedal detected by the accelerator sensor 120. Also, the HEV ECU 110 refers to the output signal Sp of the output-side rotation angle sensor 122 that detects the rotation angle of the ring gear R. Further, the HEV ECU 110 refers to the charge / discharge current Ib of the battery 59 detected by the current sensor 124 and the terminal voltage Vb of the battery 59 detected by the voltage sensor 126. The CPU 112, ROM 114, and peripheral circuit 116 included in the HEV ECU 110 are communicable via the communication line 118. After calculating the command values by the CPU 112 executing the program stored in the ROM 114, the HEV ECU 110 outputs the calculated command values to the outside.

[0021] Hereinafter, among the processes executed by the vehicle control system, in particular, the regeneration process of the GPF 34, the command process by the HEV ECU 110, and the operation process of the throttle valve 14 by the ENG ECU 70 will be described in detail.

[0022] <Regeneration Process of GPF 34> FIG. 2 shows the procedure of the regeneration process. The process shown in FIG. 2 is realized by the CPU 72 repeatedly executing the program stored in the ROM 74 of the ENG ECU 70, for example, at a predetermined cycle. In the following, the step numbers of each process are represented by numbers with "S" added at the beginning.

[0023] In the series of processes shown in FIG. 2, the CPU 72 first acquires the engine speed Ne, the charging efficiency η, and the water temperature THW (S10). Next, the CPU 72 calculates an update amount ΔDPM for the accumulation amount DPM based on the engine speed Ne, the charging efficiency η, and the water temperature THW (S12). The charging efficiency η is calculated by the CPU 72 based on the intake air amount Ga and the engine speed Ne. The accumulation amount DPM is the amount of PM trapped in the GPF 34. More specifically, the CPU 72 calculates the amount of PM in the exhaust gas discharged to the exhaust passage 30 based on the engine speed Ne, the charging efficiency η, and the water temperature THW. The CPU 72 also calculates the temperature of the GPF 34 based on the engine speed Ne and the charging efficiency η. The CPU 72 then calculates the update amount ΔDPM based on the amount of PM in the exhaust gas and the temperature of the GPF 34. When executing the process of S20 described below, the temperature of the GPF 34 and the update amount ΔDPM may be calculated based on the increase coefficient K.

[0024] Next, the CPU 72 updates the accumulation amount DPM by adding the update amount ΔDPM to the accumulation amount DPM (S14). Next, the CPU 72 determines whether or not a flag F is "1" (S16). If the flag F is "1", this indicates that a temperature increase process is being performed to burn off and remove PM from the GPF 34. On the other hand, if the flag F is "0", this indicates that a temperature increase process is not being performed. If the CPU 72 determines that the flag F is "0" (S16: NO), it determines whether or not the accumulation amount DPM is equal to or greater than a regeneration execution value DPMH (S18). The regeneration execution value DPMH is a threshold value for determining that the amount of PM trapped by the GPF 34 has increased based on the accumulation amount DPM being equal to or greater than the regeneration execution value DPMH.

[0025] When the CPU 72 determines that the regeneration execution value DPMH is equal to or greater than the regeneration execution value DPMH (YES in S18), the CPU 72 executes a temperature increase process and sets flag F to "1" (S20). As the temperature increase process according to this embodiment, the CPU 72 stops fuel injection from the in-cylinder injection valve 22 of cylinder #1 during load operation of the engine 10, and makes the air-fuel ratio of the mixture in the combustion chamber 18 of cylinders #2, #3, and #4 richer than the stoichiometric air-fuel ratio. This process is, first, a stop process for increasing the temperature of the three-way catalyst 32. That is, by discharging oxygen and unburned fuel into the exhaust passage 30, the unburned fuel is oxidized in the three-way catalyst 32, thereby increasing the temperature of the three-way catalyst 32. Second, the temperature increase process is a process for increasing the temperature of the GPF 34 and supplying oxygen to the heated GPF 34 to oxidize and remove PM trapped by the GPF 34. That is, when the temperature of the three-way catalyst 32 becomes high, high-temperature exhaust gas flows into the GPF 34, causing the temperature of the GPF 34 to rise. Then, oxygen flows into the high-temperature GPF 34, causing the PM trapped by the GPF 34 to be oxidized and removed.

[0026] Specifically, the CPU 72 assigns "0" to the required injection amount Qd for the in-cylinder injection valve 22 of cylinder #1 during the stop processing. That is, in this case, cylinder #1 becomes a stopped cylinder to which fuel supply is stopped. Meanwhile, the CPU 72 assigns a value obtained by multiplying the base injection amount Qb by the increase coefficient K to the required injection amount Qd for cylinders #2, #3, and #4 during the stop processing. The base injection amount Qb is the amount of fuel required to make the air-fuel ratio of the mixture in the combustion chamber 18 the stoichiometric air-fuel ratio.

[0027] The CPU 72 sets the increase coefficient K so that the amount of unburned fuel in the exhaust gas discharged from cylinders #2, #3, and #4 into the exhaust passage 30 does not exceed the amount that reacts just enough with the oxygen discharged from cylinder #1. Specifically, the CPU 72 sets the increase coefficient K to a larger value when the temperature of the GPF 34 is low than when it is high.

[0028] On the other hand, if the CPU 72 determines that the regeneration execution value is less than the regeneration execution value DPMH (S18: NO), it ends this series of processes. When the CPU 72 determines that the flag F is "1" (YES in S16), the CPU 72 determines whether the accumulation amount DPM is equal to or less than a stop lower limit guard value DPML (S24). The stop lower limit guard value DPML is a threshold value for determining that the amount of PM trapped in the GPF 34 has become sufficiently small based on the accumulation amount DPM being equal to or less than the stop lower limit guard value DPML.

[0029] When the CPU 72 determines that the detected value is greater than the lower limit guard value DPML for stop (S24: NO), the CPU 72 proceeds to the process of S20. On the other hand, if the detected value is equal to or less than the stop lower limit guard value DPML (S24: YES), the CPU 72 stops the process of S20 and sets flag F to "0" (S26). When the CPU 72 completes the processes of S20 and S26, it temporarily ends the series of processes shown in FIG. 2.

[0030] In this way, the ENGECU 70 executes the playback process. (Command processing by HEVECU110) In this vehicle control system, the HEVECU 110 calculates the required engine speed Ne* and the required engine power Pe* and transmits them to the ENGECU 70. The ENGECU 70 then controls the engine 10 in accordance with the received required engine speed Ne* and required engine power Pe*.

[0031] The ENGECU 70 calculates the required engine torque Te* from the required engine output Pe*. The solid line L1 shown in FIG. 3 is the optimum fuel economy line. The optimum fuel economy line is a line connecting the operating points where the fuel economy of the engine 10 is the best. The operating points shown in FIG. 3 are points determined by the combination of the engine speed Ne and the engine torque Te. The engine torque Te is the torque at the crankshaft 26, i.e., the shaft torque.

[0032] Lines L2 to L4 shown in FIG. 3 are contour lines of engine output power Pe. Operating points on each line are operating points where the engine output power Pe is equal. In the example shown in FIG. 3, the engine output power Pe increases toward the upper right region in FIG. 3. That is, the engine output power Pe indicated by the dashed line L4 is higher than the engine output power Pe indicated by the solid line L2. Furthermore, the engine output power Pe indicated by the broken line L3 is lower than the engine output power Pe indicated by the solid line L2.

[0033] The ENGECU 70 calculates the engine torque Te at an operating point corresponding to the intersection of the required engine output Pe* and the optimal fuel economy line, and sets the engine torque Te as the required engine torque Te*.

[0034] 4 shows the procedure for calculating the required engine output base value Peb* by the HEVECU 110. The required engine output base value Peb* is a value for calculating the required engine output Pe*. The process shown in FIG. 4 is realized by the CPU 112 repeatedly executing a program stored in the ROM 114, for example, at a predetermined interval.

[0035] 4, the CPU 112 first acquires the accelerator operation amount ACCP and the output side rotation speed Np (S30). The output side rotation speed Np is the rotation speed of the ring gear R. In other words, the output side rotation speed Np is a variable indicating the vehicle speed. The output side rotation speed Np is calculated by the CPU 112 based on the output signal Sp.

[0036] The CPU 112 calculates a required drive torque Tp*, which is the torque required for the drive wheels 60, based on the accelerator operation amount ACCP and the output side rotation speed Np (S32). Next, the CPU 112 assigns the product of the required drive torque Tp* and the output side rotation speed Np to the traveling power Pp* (S34). Next, the CPU 112 calculates a required charge / discharge power Pd* of the battery 59 based on the state of charge (SOC) of the battery 59 (S36). The required charge / discharge power Pd* is set to a positive value when discharging. More specifically, when the state of charge (SOC) is equal to or lower than a predetermined value, the CPU 112 sets the required charge / discharge power Pd* to a negative value so as to charge the battery 59. The state of charge (SOC) is calculated by the CPU 112 based on the charge / discharge current Ib and the terminal voltage Vb.

[0037] Next, CPU 112 subtracts the product of required charge / discharge power Pd* and conversion efficiency Kef from the running power Pp*, and assigns the result to system output Ps* (S38). Then, CPU 112 determines whether the vehicle is running steadily (S40). CPU 112 determines that the vehicle is running steadily, for example, when the amount of change per unit time in required drive torque Tp* is equal to or less than a predetermined amount and the amount of change per unit time in output side rotation speed Np is equal to or less than a predetermined amount.

[0038] When the CPU 112 determines that the vehicle is not in steady driving mode (S40: NO), it assigns the system output Ps* to the required engine output base value Peb* (S42). On the other hand, when the CPU 112 determines that the vehicle is in steady driving mode (S40: YES), it assigns a value obtained by adding the feedback correction amount FB to the system output Ps* to the required engine output base value Peb* (S44). The feedback correction amount FB is a manipulated variable for feedback-controlling the charge / discharge power of the battery 59 to the required charge / discharge power Pd*. Here, the actual charge / discharge power of the battery 59 is calculated by the CPU 112 as the product of the charge / discharge current Ib and the terminal voltage Vb. When the value obtained by subtracting the actual charge / discharge power from the required charge / discharge power Pd* is smaller than the lower limit, the CPU 112 increases the feedback correction amount FB by a predetermined amount. On the other hand, when the value obtained by subtracting the actual charge / discharge power from the required charge / discharge power Pd* is larger than the upper limit, the CPU 112 decreases the feedback correction amount FB by a predetermined amount.

[0039] When the CPU 112 completes the processes of S42 and S44, it temporarily ends the series of processes shown in Fig. 4. In this way, the HEVECU 110 executes the calculation of the required engine output base value Peb*.

[0040] <About compensation processing> However, when the stop process is being performed, fuel supply to the stopped cylinders is stopped, resulting in a shortage of output.

[0041] Specifically, when the stop process is not being executed, the combustion torque is the sum of the torque generated by combustion in the four cylinders, as shown in Figure 5. The torque obtained by subtracting the torque loss due to the influence of pumping loss and friction loss, indicated by the arrows, from this combustion torque is the shaft torque.

[0042] On the other hand, when the stop process is being performed, combustion does not occur in cylinder #1, so the combustion torque is small, as shown in Figure 6. The torque obtained by subtracting the torque loss due to the influence of pumping loss and friction loss, indicated by the arrows, from this combustion torque is the axial torque.

[0043] For example, as shown in Fig. 3, when the required engine output power Pe* is indicated by the solid line L2 and the stop process is not being executed, the HEVECU 110 sets the required engine speed Ne* to "Ne1," which is the engine speed Ne at the operating point X2. Then, the ENGECU 70, which has received the required engine speed Ne* and the required engine output power Pe*, controls the engine 10. As a result, the engine 10 is controlled so that the engine speed Ne becomes "Ne1" and the engine torque Te becomes "Te1."

[0044] On the other hand, when the stop process is being executed, the engine torque Te is reduced by the amount of the stopped cylinder. Therefore, even if the HEVECU 110 sets the requested engine speed Ne* to "Ne1," the engine torque Te becomes "Te2," which is lower than "Te1." As a result, the engine output Pe reaches the level indicated by the dashed line L3. This vehicle control system drives the second motor-generator 54 to compensate for the shortage of engine output Pe. However, compensating for the output by the second motor-generator 54 in this way increases power consumption and reduces energy efficiency.

[0045] Therefore, this vehicle control system performs a compensation process to compensate for the insufficient output by combustion in cylinders other than the stopped cylinder. Specifically, the required engine output Pe* is increased as indicated by the white arrow in FIG. 3. For example, as shown in FIG. 3, the required engine output Pe* is increased from the level indicated by the solid line L2 to the level indicated by the dashed-dotted line L4. As a result, the engine 10 is controlled so that the operating point is located on the solid line L2, as indicated by the operating point X4 in FIG. 3, even when the stop process is being performed. In other words, when the stop process is being performed, the required engine output base value Peb* is multiplied by the correction coefficient Kpe to increase the required engine output Pe*, thereby changing the operating point of the engine 10 and compensating for the insufficient output.

[0046] The magnitude of the influence of pumping loss and friction loss varies depending on the operating state of the engine 10. Therefore, the magnitude of the correction coefficient Kpe required for compensation varies depending on the operating state of the engine 10 at that time.

[0047] Therefore, in this vehicle control system, the magnitude of the correction coefficient Kpe is adjusted by a compensation process according to the operating state of the engine 10. <Processing for calculating the correction coefficient Kpe> Next, the process for calculating the correction coefficient Kpe will be described with reference to Fig. 7. The process shown in Fig. 7 is implemented by the CPU 112 executing a program stored in the ROM 114 of the HEVECU 110 every time the required engine output base value Peb* is updated.

[0048] In the series of processes shown in FIG. 7, the CPU 112 first obtains the required engine output base value Peb* (S50). The CPU 112 calculates the engine speed Ne used to calculate the correction coefficient Kpe based on the required engine output base value Peb* (S52). This can be achieved by having the CPU 112 perform map calculations on the engine speed Ne while map data is stored in advance in the ROM 114. Here, the map data is data that uses the required engine output base value Peb* as an input variable and the engine speed Ne as an output variable. The map data is a set of data that includes discrete values ​​of the input variables and values ​​of the output variables corresponding to each of the input variable values. The map calculation may be a process in which, when the value of an input variable matches any of the input variable values ​​in the map data, the value of the output variable in the corresponding map data is used as the calculation result. When the value of an input variable does not match any of the input variable values ​​in the map data, the map calculation may be a process in which the value obtained by interpolating the values ​​of multiple output variables included in the map data is used as the calculation result.

[0049] Next, the CPU 112 calculates the engine torque Te used to calculate the correction coefficient Kpe (S54). Here, the CPU 112 calculates the engine torque Te used to calculate the correction coefficient Kpe by performing division using the required engine output base value Peb* as the dividend and the engine speed Ne calculated in S52 as the divisor.

[0050] Then, CPU 112 calculates a correction coefficient Kpe based on the engine speed Ne calculated through S52 and the engine torque Te calculated through S54 (S56). This can be achieved by performing map calculations on the correction coefficient Kpe with map data for calculating the correction coefficient Kpe stored in advance in ROM 114. Input variables of the map data for calculating the correction coefficient Kpe are the engine speed Ne calculated through S52 and the engine torque Te calculated through S54. The output variable of this map data is the correction coefficient Kpe.

[0051] FIG. 8 shows this map data. The correction coefficient Kpe calculated using this map data is a value greater than "1.0." The range surrounded by a solid line in FIG. 8 indicates the range in which "1.43" is output as the correction coefficient Kpe. The range surrounded by a dashed line in FIG. 8 indicates the range in which "1.40" is output as the correction coefficient Kpe. In this map data, when compared under the same condition of engine speed Ne, the correction coefficient Kpe decreases as the engine torque Te increases. Furthermore, in this map data, when compared under the same condition of engine torque Te, the correction coefficient Kpe increases as the engine speed Ne increases.

[0052] When the processing of S56 is completed, the CPU 112 determines whether the flag F is "1" (S58). When the CPU 112 determines that the flag F is "0" (S58: NO), the CPU 112 assigns the required engine output base value Peb* to the required engine output Pe* (S62).

[0053] On the other hand, when the CPU 112 determines that the flag F is "1" (S58: YES), it assigns "Peb* x Kpe" to the requested engine power Pe* (S60). That is, the CPU 112 performs a correction to increase the requested engine power Pe* by multiplying the requested engine power base value Peb* by the correction coefficient Kpe and setting the product as the requested engine power Pe*.

[0054] When the processes of S60 and S62 are completed, the CPU 112 calculates the required engine speed Ne* (S64). Specifically, the CPU 112 calculates the required engine speed Ne* from the required engine output Pe*, as described with reference to Fig. 3. That is, the CPU 112 sets the engine speed Ne at the operating point corresponding to the intersection of the required engine output Pe* and the optimal fuel economy line as the required engine speed Ne*.

[0055] Next, the CPU 112 outputs the required engine power Pe* and the required engine speed Ne* to the ENGECU 70 (S66). When S66 ends, the CPU 112 temporarily ends the series of processes shown in FIG.

[0056] <Operation process of the throttle valve 14> 9 shows a procedure for processing related to the operation of the throttle valve 14. The processing shown in FIG. 9 is realized by the CPU 72 repeatedly executing a program stored in the ROM 74 of the engine control unit 70 at a predetermined interval.

[0057] In the series of processes shown in FIG. 9, the CPU 72 first receives a required engine output Pe* and a required engine speed Ne* (S80). The CPU 72 then calculates a required engine torque Te* based on the required engine output Pe* and the required engine speed Ne*. The CPU 72 then calculates a throttle opening command value TA*, which is a command value for the opening of the throttle valve 14, based on the required engine torque Te* and the required engine speed Ne* (S82). The throttle opening command value TA* calculated here is a throttle opening value for achieving the required engine torque Te* and the required engine speed Ne* when combustion control is performed for all of cylinders #1 to #4. The CPU 72 then outputs an operation signal MS1 to the throttle valve 14 to control the opening of the throttle valve 14 to the throttle opening command value TA* (S84). When the CPU 72 completes the process of S84, it temporarily ends the series of processes shown in FIG. 9.

[0058] <Operation of this embodiment> The CPU 112 of the HEVECU 110 calculates a correction coefficient Kpe for increasing the required engine power Pe* based on the engine speed Ne and the engine torque Te through the processing of S50 to S56. That is, the processing of S50 to S56 is a correction coefficient calculation process that calculates the correction coefficient Kpe for increasing the required engine power Pe* based on the engine speed Ne and the engine torque Te.

[0059] Then, when the stop process is being executed (S58: YES), the CPU 112 of the HEVECU 110 multiplies the required engine output base value Peb* by the correction coefficient Kpe to obtain the required engine output Pe*. This corrects the required engine output Pe*, increasing it. Then, the CPU 112 calculates the required engine speed Ne* based on the corrected required engine output Pe* and outputs it to the ENGECU 70 (S64, S66).

[0060] The ENGECU 70 receives the required engine output power Pe* and the required engine speed Ne*, calculates the required engine torque Te* based on the received required engine output power Pe* and required engine speed Ne*, and calculates a throttle opening command value TA* based on the calculated required engine torque Te* and required engine speed Ne* (S82).The ENGECU 70 then controls the throttle valve 14 based on the throttle opening command value TA* (S84).

[0061] In this way, through the processes of S60, S64, S66, S80, S82, and S84, this vehicle control system compensates for the output reduction caused by the execution of the stop process while the stop process is being executed by increasing the output generated by combustion in the remaining cylinders. In other words, the processes of S60, S64, S66, S80, S82, and S84 are compensation processes.

[0062] <Effects of this embodiment> (1) When compared under the same engine speed Ne, the vehicle control system reduces the increase in output power through the compensation process as the engine torque Te increases. The amount of output power reduced by the execution of the stop process, i.e., the amount of engine power power Pe that must be compensated, varies depending on the engine speed Ne and the engine torque Te. When compared under the same engine speed Ne, the amount of engine power power Pe that must be compensated decreases as the engine torque Te increases. In accordance with this tendency, the vehicle control system reduces the increase in engine power power Pe through the compensation process as the engine torque Te increases. Therefore, the amount of engine power power Pe that is increased through the compensation process can be changed in accordance with changes in the amount of engine power power Pe that must be compensated. Therefore, the output power can be appropriately compensated.

[0063] (2) When compared under the same condition of engine torque Te, the above-described vehicle control system increases the output power increased by the compensation process as the engine speed Ne increases. When compared under the same condition of engine torque Te, the higher the engine speed Ne, the greater the amount of output power that must be compensated. According to the above-described vehicle control system, in accordance with this tendency, the higher the engine speed Ne, the greater the increase in engine power power Pe increased by the compensation process. Therefore, the amount of engine power power Pe increased by the compensation process can be changed in accordance with changes in the amount of engine power power Pe that must be compensated. Therefore, the output power can be appropriately compensated.

[0064] (3) In the compensation process, the HEVECU 110 increases the engine output Pe generated by the remaining cylinders by correcting the required engine output Pe* to be higher than the required engine output Pe* when the stop process is not executed. Therefore, the engine output Pe increased by the compensation process can be controlled by manipulating the required engine output Pe* calculated by the HEVECU 110.

[0065] (4) The HEVECU 110 calculates the engine speed Ne used to calculate the correction coefficient Kpe, separately from the requested engine speed Ne* to be transmitted to the ENGINE CU 70. Then, in the correction coefficient calculation process, the HEVECU 110 calculates the correction coefficient Kpe based on the engine speed Ne and the engine torque Te.

[0066] If the correction coefficient Kpe is calculated based on the requested engine speed Ne* transmitted to the ENGECU 70, the correction coefficient Kpe will be calculated based on the requested engine speed Ne* that has fluctuated due to the correction of the requested engine power Pe*. This causes the requested engine power Pe* to continue fluctuating. In other words, robustness is reduced.

[0067] In contrast, in the above-described vehicle control system, the HEVECU 110 calculates the engine speed Ne used to calculate the correction coefficient Kpe separately from the required engine speed Ne*. Therefore, the correction coefficient Kpe can be calculated without being affected by the correction of the required engine power Pe*. In other words, robustness is improved.

[0068] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0069] The map data shown in FIG. 8 is created by adjusting the magnitude of the correction coefficient Kpe based on the results of preliminary experiments, etc., so as to compensate for the output loss caused by the execution of the stop process. However, even after the compensation process is executed, the engine output Pe may still be insufficient or excessive. Therefore, the vehicle control system may store a learning value corresponding to the magnitude of the engine output Pe when the compensation process is executed, and further correct the required engine output Pe* according to the magnitude of the stored learning value. By adopting such a configuration, the required engine output Pe* may be further corrected according to the magnitude of the learning value, thereby compensating for the engine output Pe that is not fully compensated for by the compensation process, or suppressing the engine output Pe that becomes excessive due to the compensation process.

[0070] An example has been given in which the correction coefficient Kpe is calculated based on the engine speed Ne and the engine torque Te. However, it is not essential to change the correction coefficient Kpe according to the engine speed Ne. In other words, it is not essential to change the correction amount of the engine output Pe according to the engine speed Ne. The correction coefficient Kpe may be calculated based only on the engine torque Te.

[0071] Although a hybrid vehicle has been exemplified, the vehicle is not limited to a hybrid vehicle. For example, the vehicle may have only the engine 10 as its driving power source. In this case, the vehicle control system may include, for example, the ENGECU 70. The ENGECU 70 may correct the required engine power Pe*.

[0072] The number of cylinders for which combustion control is stopped during the stop process is not limited to one. The GPF 34 is not limited to being provided downstream of the three-way catalyst 32 in the exhaust passage 30. Furthermore, the provision of the GPF 34 is not essential. The GPF 34 is not limited to being a filter carrying a three-way catalyst. For example, if a three-way catalyst is provided upstream, the GPF 34 may be a filter alone.

[0073] The vehicle control system is not limited to one configured with multiple electronic control devices that can communicate with each other. For example, it may be one configured with a single electronic control device.

[0074] The vehicle control system is not limited to one equipped with a CPU 72, 112 and a ROM 74, 114 and executing software processing. For example, a dedicated hardware circuit, such as an ASIC, may be provided to execute hardware processing of at least a portion of the software processing performed in the above embodiments. That is, the vehicle control system may have any of the following configurations (a) to (c): (a) A processing device that executes all of the above processing according to a program, and a program storage device, such as a ROM, that stores the program; (b) A processing device and program storage device that executes part of the above processing according to a program, and a dedicated hardware circuit that executes the remaining processing; or (c) A dedicated hardware circuit that executes all of the above processing. Here, the software execution device equipped with a processing device and program storage device, and the dedicated hardware circuit may be one or any number of them.

[0075] Instead of directly connecting the ring gear R and the second motor generator 54, a reduction gear may be interposed therebetween. The hybrid vehicle is not limited to a series-parallel hybrid vehicle. For example, a parallel hybrid vehicle may be used. Even in this case, when a regeneration process or the like is performed, it is not always possible to compensate for the decrease in engine output Pe by the motor generator depending on the state of charge (SOC) of the battery 59. Therefore, it is effective to increase the output of the engine 10 in the manner described in the above embodiment. [Explanation of symbols]

[0076] 10...Engine 14...Throttle valve 18...Combustion chamber 26...Crankshaft 30...Exhaust passage 32...Three-way catalyst 34...GPF 70...ENGECU 72...CPU 74...ROM 76...Peripheral circuit 78...Communication line 80...Air flow meter 82...Crank angle sensor 88...Water temperature sensor 90…MGECU 92...CPU 94...ROM 96...Peripheral circuit 98...Communication line 110…HEVECU 112...CPU 114...ROM 116...Peripheral circuit 118...Communication line

Claims

1. It is applied to a vehicle equipped with an engine having multiple cylinders and a filter that captures particulate matter in the exhaust, a stop process for stopping fuel supply to some of the cylinders and supplying fuel to the remaining cylinders when the engine is operating under load and the amount of particulate matter trapped in the filter is equal to or greater than a regeneration execution value; a compensation process for increasing the output generated by combustion in the remaining cylinders to compensate for the output reduced in the part of the cylinders due to the execution of the stop process while the stop process is being executed; When compared under the same engine rotation speed, the greater the shaft torque on the crankshaft of the engine, the smaller the output increased by the compensation process. Vehicle control systems.

2. When compared under the same condition of the shaft torque, the higher the engine speed, the larger the output increased by the compensation process. The vehicle control system of claim 1 .

3. The present invention is applied to a hybrid vehicle equipped with the engine and a motor as driving power sources, an engine control device that controls the engine; a vehicle control device that calculates a required engine speed and a required engine output, and transmits the required engine speed and the required engine output to the engine control device, the engine control device controls the engine in accordance with the requested engine speed and the requested engine output received from the vehicle control device, In the compensation process, the vehicle control device increases the output generated by the remaining cylinders by making a correction to increase the requested engine output compared to the requested engine output when the stop process is not executed.

3. The vehicle control system according to claim 1 or 2.

4. the vehicle control device executes a correction coefficient calculation process to calculate a correction coefficient for increasing the requested engine output based on the engine rotation speed and the shaft torque; The vehicle control device calculates an engine rotation speed used to calculate the correction coefficient separately from the requested engine rotation speed transmitted to the engine control device.

4. The vehicle control system according to claim 3.

5. A learning value corresponding to the magnitude of the excess or deficiency of the output when the compensation process is executed is stored, and the requested engine output is further corrected according to the magnitude of the stored learning value.

5. The vehicle control system according to claim 4.

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