Hybrid vehicle control device

Abstract

To increase a temperature of an exhaust emission control device while satisfactorily ensuring controllability of a multi-cylinder engine under a low-temperature environment.SOLUTION: A control device for a hybrid vehicle according to the present disclosure includes first and second control units. The first control unit sets target power of a multi-cylinder engine, and according to a vehicle state, requests execution of throttle feedback control for executing feedback control of an opening of a throttle valve so that output torque from the multi-cylinder engine becomes equal to target torque according to the target power. The second control unit executes the throttle feedback control in response to the request from the first control unit. When a temperature increase of an exhaust emission control device is requested during load operation of the multi-cylinder engine, the second control unit executes partial-cylinder fuel cut control for stopping fuel supply to at least one of cylinders, on condition that the throttle feedback control is not being executed.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to a control device and a control method for a hybrid vehicle including a multi-cylinder engine having a throttle valve, an electric motor, and an electricity storage device. [Background technology]

[0002] Conventionally, hybrid vehicles have been known that include an internal combustion engine whose output is adjusted by the throttle opening, an electricity storage device, a rotating electric machine capable of generating electricity using the power of the internal combustion engine and exchanging electricity with the electricity storage device, and a control device (see, for example, Patent Document 1). The control device for this hybrid vehicle includes a calculation unit that calculates a feedback amount of the throttle opening to bring the torque of the internal combustion engine closer to a target torque, and a control unit that sets the target opening by reflecting the feedback amount and controls the throttle opening to the target opening. The calculation unit of the control device also reduces the absolute value of the feedback amount as the temperature of the electricity storage device increases. As a result, even if the power allowed for charging the electricity storage device (allowable charging power) becomes very low at extremely low temperatures, the throttle opening during load operation can be minutely controlled on the engine side so that the charging power of the electricity storage device does not exceed the allowable charging power.

[0003] Also, a known hybrid vehicle includes an engine capable of injecting fuel into each cylinder, an exhaust gas purification device that purifies the exhaust gas from the engine, and a control device that executes cold start control to increase the amount of fuel injected during cold start of the engine (see, for example, Patent Document 2). When a request to increase the temperature of the exhaust gas purification device is made during execution of the cold start control and the fuel increase amount in the cold start control falls below a first predetermined amount, the control device of this hybrid vehicle executes temperature increase control to stop the fuel supply to some cylinders and increase the fuel supplied to the remaining cylinders. This makes it possible to suppress a decrease in the accuracy of the air-fuel ratio even when the increase in the fuel amount due to the cold start control and the increase in the fuel amount due to the temperature increase control overlap. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-168124 [Patent Document 2] Patent Publication No. 2021-167585 Summary of the Invention [Problem to be solved by the invention]

[0005] In the hybrid vehicle described in Patent Document 1, by executing the temperature increase control described in Patent Document 2, which stops the fuel supply to some of the cylinders of the engine, it is possible to increase the temperature of the exhaust gas purification device while suppressing a decrease in the accuracy of the air-fuel ratio in a low-temperature environment. However, if the fuel supply to some of the cylinders is stopped in a low-temperature environment where the allowable charging power of the power storage device becomes small as charging power (the absolute value becomes small), there is a risk that it will become difficult to ensure the SOC by using power from the engine to charge the power storage device due to deterioration in engine controllability.

[0006] Therefore, a main object of the present disclosure is to raise the temperature of an exhaust gas purification device while ensuring good controllability of a multi-cylinder engine in a low-temperature environment. [Means for solving the problem]

[0007] The control device for a hybrid vehicle disclosed herein includes a multi-cylinder engine having a throttle valve, an exhaust gas purification device that purifies exhaust gas from the multi-cylinder engine, an electric motor that can generate electricity using at least a portion of the power from the multi-cylinder engine, and an electricity storage device that exchanges electric power with the electric motor, and further includes: a first control unit that sets a target power of the multi-cylinder engine and requests execution of throttle feedback control that feedback controls, according to a vehicle state, an opening of the throttle valve so that the output torque of the multi-cylinder engine becomes a target torque according to the target power; and a second control unit that executes the throttle feedback control according to a request from the first control unit and, when a temperature increase of the exhaust gas purification device is requested during load operation of the multi-cylinder engine, executes partial-cylinder fuel cut control that stops fuel supply to at least one cylinder on the condition that the throttle feedback control is not being executed.

[0008] In addition, the control method for a hybrid vehicle disclosed herein includes a multi-cylinder engine having a throttle valve, an exhaust gas purification device that purifies exhaust gas from the multi-cylinder engine, an electric motor capable of generating electricity using at least a portion of the power from the multi-cylinder engine, and an electric storage device that exchanges power with the electric motor, and when throttle feedback control is being executed that feedback controls the opening of the throttle valve so that the output torque of the multi-cylinder engine becomes a target torque, the control method prohibits the execution of partial cylinder fuel cut control that stops fuel supply to at least one cylinder of the multi-cylinder engine. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic configuration diagram showing a hybrid vehicle controlled by a control device of the present disclosure. [Figure 2] FIG. 2 is a schematic diagram showing the configuration of a multi-cylinder engine included in the hybrid vehicle of FIG. [Figure 3]1 is a control block diagram showing a control device for a hybrid vehicle according to the present disclosure. [Figure 4] 4 is a flowchart showing an example of a routine executed by a first control unit of a control device for a hybrid vehicle of the present disclosure to determine whether or not throttle feedback control needs to be performed. [Figure 5] 4 is a flowchart showing an example of a routine executed by a first control unit of a control device for a hybrid vehicle of the present disclosure to determine whether or not to stop throttle feedback control. [Figure 6] 5 is a flowchart showing a routine executed by a second control unit of the control device for a hybrid vehicle of the present disclosure to determine whether or not to execute fuel cut control for some cylinders. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, embodiments of the present disclosure will be described with reference to the drawings.

[0011] 1 is a schematic configuration diagram of a hybrid vehicle (HEV) 1 controlled by a control device of the present disclosure. The hybrid vehicle 1 shown in the figure includes an engine 2, a single-pinion planetary gear 3 as a power distribution mechanism, a gear train 4, motor generators MG1 and MG2, both of which are synchronous generator motors (three-phase AC motors), a battery (electricity storage device) 5, a power control device (hereinafter referred to as "PCU") 6 connected to the battery 5 and driving the motor generators MG1 and MG2, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 100 as a first control unit that controls the entire vehicle.

[0012] The engine 2 of the hybrid vehicle 1 is a multi-cylinder gasoline engine (for example, an in-line four-cylinder engine or a V-type six-cylinder engine) that converts the reciprocating motion of pistons 21, which is caused by the combustion of a mixture of hydrocarbon fuel and air in a plurality of combustion chambers (cylinders) 20 formed in an engine block, into the rotational motion of a crankshaft (output shaft) 22. As shown in Fig. 2, in addition to the plurality of combustion chambers 20, pistons 21, and crankshaft 22, the engine 2 also includes an air cleaner 23, an intake pipe 24, an electronically controlled throttle valve 25, an intake manifold 26 having a surge tank and a plurality of intake ports, a plurality of intake valves 27i that open and close the corresponding intake ports, exhaust valves 27e that open and close the corresponding exhaust ports, a plurality of port injection valves 28p that inject fuel into the corresponding intake ports, a plurality of in-cylinder injection valves 28d that directly inject fuel into the corresponding combustion chambers 20, a plurality of spark plugs 29, and an exhaust pipe 30 that forms an exhaust passage.

[0013] The engine 2 also includes, as exhaust gas purification devices, an upstream purification device 31 and a downstream purification device 32, each incorporated in an exhaust pipe 30. The upstream purification device 31 includes a NOx storage-type exhaust gas purification catalyst (three-way catalyst) that purifies harmful components such as CO (carbon monoxide), HC, and NOx in exhaust gas from each combustion chamber 20 of the engine 2. The downstream purification device 32 includes a particulate filter PF (GPF) that collects particulate matter (fine particles) in the exhaust gas, and is disposed downstream of the upstream purification device 31. In this embodiment, the particulate filter PF is a porous filter that supports a NOx storage-type exhaust gas purification catalyst (three-way catalyst). That is, the downstream purification device 32 includes a four-way catalyst that combines the purification function of a three-way catalyst with the function of collecting particulate matter.

[0014] The engine 2 further includes a supercharger 33 that compresses intake air using the energy of exhaust gas, and a liquid-cooled intercooler 34 that cools the air compressed by the supercharger 33. The supercharger 33 is a turbocharger and includes a turbine wheel 33t, a compressor wheel 33c, a turbine shaft 33s that integrally connects the turbine wheel 33t and the compressor wheel 33c, a wastegate valve 33w, and a blow-off valve 33b. The turbine wheel 33t is rotatably disposed in a turbine housing formed in the exhaust pipe 30 so as to be located upstream of the upstream purification device 31. The compressor wheel 33c is rotatably disposed in a compressor housing formed in the intake pipe 24 so as to be located between the air cleaner 23 and the throttle valve 25.

[0015] The engine 2 configured as described above is controlled by an engine electronic control unit (hereinafter referred to as "engine ECU") 200 serving as a second control unit including a microcomputer having a CPU, ROM, RAM, input / output interfaces, etc. (not shown), various drive circuits, various logic ICs, etc. As shown in Fig. 3, the engine ECU 200 acquires detection values from the crank angle sensor 22a, air flow meter 24a, intake pressure sensor 24p, boost pressure sensor 24c, intake air temperature sensor 24t, throttle opening sensor 25o, surge pressure sensor 26p, temperature sensor 26t, upstream air-fuel ratio sensor 30f, downstream air-fuel ratio sensor 30r, exhaust gas temperature sensor 30t, water temperature sensor 35t, etc. via input ports (not shown).

[0016] The crank angle sensor 22a detects the rotational position (crank position) of the crankshaft 22. The air flow meter 24a detects the intake air amount Qa upstream of the compressor wheel 33c of the intake pipe 24. The intake pressure sensor 24p detects the intake pressure Pin upstream of the compressor wheel 33c of the intake pipe 24. The boost pressure sensor 24c detects the boost pressure Pc, which is the pressure of air compressed by the compressor wheel 33c between the compressor housing of the intake pipe 24 and the intercooler 34. The intake air temperature sensor 24t detects the intake air temperature Tin upstream of the compressor wheel 33c of the intake pipe 24.

[0017] The throttle opening sensor 25o detects the opening of the throttle valve 25. The surge pressure sensor 26p detects the surge pressure Ps, which is the pressure of the air in the surge tank, and the temperature sensor 26t detects the surge temperature Ts, which is the temperature of the air in the surge tank. The upstream air-fuel ratio sensor 30f detects the upstream air-fuel ratio AFf, which is the air-fuel ratio of exhaust gas flowing into the upstream purification device 31, upstream of the upstream purification device 31, and the downstream air-fuel ratio sensor 30r detects the downstream air-fuel ratio AFr, which is the air-fuel ratio of exhaust gas flowing into the downstream purification device 32, downstream of the upstream purification device 31. The exhaust gas temperature sensor 30t detects the temperature Teg of exhaust gas flowing through the portion of the exhaust pipe 30 between the upstream purification device 31 and the downstream purification device 32. The water temperature sensor 35t detects the temperature Tw of coolant (the temperature of the engine 2) that cools the engine block, etc.

[0018] The engine ECU 200 calculates the rotation speed Ne of the engine 2 (crankshaft 22) based on the crank position from the crank angle sensor 22a. The engine ECU 200 also calculates a load factor KL based on the intake air amount Qa from the air flow meter 24a and the rotation speed Ne of the engine 2. The load factor KL is the ratio of the volume of air actually taken in during one cycle to the stroke volume per cycle of the engine 2. The engine ECU 200 controls the throttle valve 25 (intake air amount), the multiple port injection valves 28p and the multiple in-cylinder injection valves 28d (fuel injection amount), the multiple ignition plugs 29 (ignition timing), and the like, based on the rotation speed Ne, the load factor KL, and the like. Furthermore, the engine ECU 200 controls the wastegate valve 33w and the blow-off valve 33b of the turbocharger 33, an electric pump (not shown) that pressure-feeds coolant, and the like. The engine 2 may be a diesel engine including a diesel particulate filter (DPF) or an LPG engine.

[0019] The planetary gear 3 is a differential rotation mechanism including a sun gear 3s, a ring gear 3r, and a planetary carrier 3c that rotatably supports a plurality of pinion gears 3p. As shown in FIG. 1, the sun gear 3s is connected to the rotor of the motor generator MG1, and the planetary carrier 3c is connected to the crankshaft 22 of the engine 2 via a damper mechanism DD. The ring gear 3r is coaxial with and rotates integrally with a counter drive gear 4a (output member) of the gear train 4. In addition to the counter drive gear 4a, the gear train 4 also includes a counter driven gear 4b and a final drive gear (drive pinion gear) 4c. The final drive gear 4c meshes with a differential ring gear Dr of a differential gear DF and is connected to left and right wheels (drive wheels) W via the differential gear DF and drive shafts DS. As a result, the planetary gear 3, the gear train 4, and the differential gear DF constitute a transaxle that transmits part of the output torque of the engine 2 as a power generation source to the wheels W and connects the engine 2 and the motor generator MG1 to each other.

[0020] Motor generator MG1 mainly operates as a generator that converts at least a portion of the power from engine 2, which is operated under load, into electric power. Motor generator MG2 is connected to left and right wheels W via a differential gear DF, which includes a drive gear 4d, a counter driven gear 4b, a final drive gear 4c, and a differential ring gear Dr, and a drive shaft DS. Motor generator MG2 mainly operates as an electric motor that is driven by at least one of the electric power from battery 5 and the electric power from motor generator MG1 and generates a drive torque on drive shaft DS.

[0021] The battery 5 is, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery. The battery 5 is managed by a battery management electronic control unit (hereinafter referred to as "battery ECU") 500, which includes a microcomputer having a CPU (not shown). The battery ECU 500 derives the SOC (charging rate), allowable charging power Win (negative value), allowable discharging power Wout (positive value), etc. of the battery 5 based on the terminal voltage VB of the battery 5 detected by a voltage sensor 5v, the charging / discharging current IB of the battery 5 detected by a current sensor, the battery temperature Tb of the battery 5 detected by a battery temperature sensor 5t, etc.

[0022] The PCU 6 includes a first inverter that drives the motor generator MG1, a second inverter that drives the motor generator MG2, a boost converter that can boost the power from the battery 5 and reduce the power from the motor generators MG1 and MG2 (all of which are not shown), etc. The PCU 6 is controlled by a motor electronic control unit (hereinafter referred to as "MGECU") 600 that includes a microcomputer having a CPU and the like (not shown).

[0023] The HVECU 100 includes a microcomputer having a CPU or the like, various drive circuits, various logic ICs, etc. As shown in Fig. 3, the HVECU 100 acquires the vehicle speed V detected by a vehicle speed sensor 90, the accelerator pedal opening Acc indicating the depression amount of an accelerator pedal (not shown) detected by an accelerator pedal position sensor 91, the shift position SP of a shift lever (not shown) detected by a shift position sensor 92, etc. Furthermore, the HVECU 100 exchanges information with the ECUs 200, 500, 600, a brake electronic control unit (not shown) that controls a hydraulic brake actuator (not shown), etc., and comprehensively controls the hybrid vehicle 1 based on the vehicle speed V, the accelerator pedal opening Acc, signals from the ECUs 200, 500, 600, etc.

[0024] When the hybrid vehicle 1 is traveling, the HVECU 100 derives a required torque Tr* (including a required braking torque) to be output to the drive shaft DS corresponding to the accelerator opening Acc and the vehicle speed V from a required torque setting map (not shown). Furthermore, the HVECU 100 sets a required traveling power Pd* (= Tr* × Nds) required for traveling of the hybrid vehicle 1 based on the required torque Tr* and the rotation speed Nds of the drive shaft DS. The HVECU 100 also determines whether to operate the engine 2 under load based on the required torque Tr*, the required traveling power Pd*, a separately set target charging / discharging power Pb* (discharging side is positive) of the battery 5, the SOC from the battery ECU 500, the allowable charging power Win, the allowable discharging power Wout, etc.

[0025] When the engine 2 is operated under load, the HVECU 100 sets a target power Pe* (=Pd*-Pb*+Loss) to be output from the engine 2 based on the required traveling power Pd*, the target charge / discharge power Pb*, etc. Furthermore, the HVECU 100 sets a target rotation speed Ne* of the engine 2 according to the target power Pe* so that the engine 2 is operated efficiently and does not fall below a lower limit rotation speed Nelim according to the operating state of the hybrid vehicle 1, etc. Furthermore, the HVECU 100 sets torque commands Tm1*, Tm2* for the motor generators MG1, MG2 according to the required torque Tr*, the target rotation speed Ne*, etc. within the ranges of the allowable charge power Win and allowable discharge power Wout of the battery 5. On the other hand, when the operation of the engine 2 is stopped, the HVECU 100 sets the target power Pe*, the target rotation speed Ne*, and the torque command Tm1* to zero. Furthermore, HVECU 100 sets torque command Tm2* within the range of allowable charging power Win and allowable discharging power Wout of battery 5 so that torque according to required torque Tr* is output from motor generator MG2 to drive shaft DS.

[0026] The HVECU 100 then transmits the target power Pe* and the target rotation speed Ne* to the engine ECU 200, and also transmits torque commands Tm1* and Tm2* to the MGECU 600. The engine ECU 200 controls the intake air amount, fuel injection amount, ignition timing, and the like based on the target rotation speed Ne* and a target torque Te* (=Pe* / Ne*) corresponding to the target power Pe* and the target rotation speed Ne*. In this embodiment, the engine ECU 200 basically executes fuel injection control so that the air-fuel ratio in each combustion chamber 20 of the engine 2 becomes the stoichiometric air-fuel ratio (=14.6-14.7). Furthermore, the engine ECU 200 injects fuel into each combustion chamber 20 from either or both of the port injection valve 28p and the in-cylinder injection valve 28d, depending on the load (target power Pe*) of the engine 2, and the like.

[0027] Furthermore, MGECU 600 controls the switching of the first and second inverters and the boost converter based on torque commands Tm1* and Tm2*. When engine 2 is operated under load, motor generators MG1 and MG2 are controlled to convert a portion (when battery 5 is charging) or all (when battery 5 is discharging) of the power output from engine 2 into torque together with planetary gear 3 and output the torque to drive shaft DS. This allows hybrid vehicle 1 to run (HV running) using power (direct torque) from engine 2 and power from motor generator MG2. On the other hand, when operation of engine 2 is stopped, hybrid vehicle 1 runs (EV running) using only power (drive torque) from motor generator MG2.

[0028] Here, the hybrid vehicle 1 of this embodiment includes a downstream purification device 32 having a particulate filter PF as an exhaust gas purification device. The amount Dpm of particulate matter deposited on the particulate filter PF increases with an increase in the mileage of the hybrid vehicle 1, and also increases as the ambient temperature decreases. Therefore, in the hybrid vehicle 1, at the stage when the amount Dpm of particulate matter deposited on the particulate filter PF increases, it is necessary to feed a large amount of air, i.e., oxygen, into the particulate filter PF whose temperature has been sufficiently raised, and burn the particulate matter to regenerate the particulate filter PF.

[0029] For this reason, in the hybrid vehicle 1, when the engine 2 is operated under load in response to depression of the accelerator pedal by the driver, a request to charge the battery 5, or the like, the engine ECU 200 executes partial cylinder fuel cut control (catalyst temperature rise control) that stops fuel supply to at least one combustion chamber 20 of the engine 2 and supplies fuel to the remaining combustion chambers 20. Furthermore, when stopping fuel supply to one combustion chamber 20 of the engine 2, the engine ECU 200 makes the air-fuel ratio in the remaining combustion chambers 20 rich. Furthermore, in this embodiment, the engine ECU 200 selects, in accordance with the temperature of the particulate filter PF, and the like, combustion chambers 20 to which fuel injection (ignition) is not continuously performed when the partial cylinder fuel cut control is not being executed, from among the combustion chambers 20 to which fuel supply has already been stopped, and stops fuel supply to the selected combustion chambers 20.

[0030] As a result, a relatively large amount of air, i.e., oxygen, is introduced into the upstream and downstream purification devices 31, 32 from the combustion chambers 20 to which fuel supply has been stopped (fuel-cut cylinders), and a relatively large amount of unburned fuel is introduced from the combustion chambers 20 to which fuel is supplied (combustion cylinders). As a result, during load operation of the engine 2, a relatively large amount of unburned fuel is reacted in the presence of sufficient oxygen, and it becomes possible to sufficiently and quickly increase the temperatures of the exhaust gas purification catalyst of the upstream purification device 31 and the particulate filter PF carrying the exhaust gas purification catalyst by the heat of reaction. Furthermore, a larger amount of oxygen is introduced from the plurality of fuel-cut cylinders to the particulate filter PF, which has been heated together with the exhaust gas purification catalyst of the downstream purification device 32, so that the particulate matter deposited on the particulate filter PF can be burned well. Therefore, in the hybrid vehicle 1, it is possible to satisfactorily combust the particulate matter deposited on the particulate filter PF and regenerate the particulate filter PF even in a low-temperature environment where a large amount of particulate matter tends to deposit on the particulate filter PF, particularly in an extremely low-temperature environment where the average daily temperature is below -20°C. In addition, in the hybrid vehicle 1, it is also possible to satisfactorily alleviate S-poisoning and HC-poisoning of the exhaust gas purification catalyst of the upstream purification device 31.

[0031] Furthermore, when the engine ECU 200 executes the partial cylinder fuel cut control, the HVECU 100 increases the target power Pe* corresponding to the same accelerator opening Acc and vehicle speed V compared to when the engine ECU 200 does not execute the partial cylinder fuel cut control. This makes it possible to suppress a decrease in the output torque of the engine 2 when the partial cylinder fuel cut control is executed. In this embodiment, while the partial cylinder fuel cut control is being executed, the HVECU 100 increases the target power Pe* by a value (increase amount) corresponding to the operating point (rotation speed and torque) of the engine 2, which is derived from a map (not shown).

[0032] Furthermore, during execution of the partial cylinder fuel cut control, the HVECU 100, in cooperation with the MGECU 600, controls the motor generator MG2 as a power generating device to compensate for the torque (driving force) shortage caused by the stop of fuel supply to at least one of the combustion chambers 20. More specifically, the HVECU 100 (and the MGECU 600) controls the motor generator MG2 (electric motor) to compensate for the torque shortage while the fuel supply to at least one of the combustion chambers 20 is stopped (during fuel cut). As a result, during execution of the partial cylinder fuel cut control, the torque shortage caused by the stop of fuel supply to some of the combustion chambers 20 can be compensated for with high accuracy and good responsiveness from the motor generator MG2, thereby making it possible to effectively suppress deterioration in the drivability of the hybrid vehicle 1.

[0033] On the other hand, in a low-temperature environment, the allowable charging power Win of the battery 5 mounted on the hybrid vehicle 1 is set to a small value (a smaller absolute value) as the battery temperature Tb decreases. Therefore, in order to keep the electric power (charging power) from the motor generator MG1, which generates power using at least a portion of the power from the engine 2 operating under load (charging power) within the range of the allowable charging power Win, it is necessary to accurately bring the power output from the engine 2 close to a relatively small target power Pe*. However, if the controllability of the engine 2 during load operation is not ensured, the electric power (charging power) from the motor generator MG1 tends to fluctuate around the allowable charging power Win, causing the operating state of the engine 2 to frequently switch between a loaded operating state and an autonomous operating state in which the engine 2 does not output any substantial torque. In such a case, the battery 5 may not be charged as required, making it impossible to ensure the SOC, or vibrations and noise may become apparent due to fluctuations in the operating state of the engine 2.

[0034] Based on this, the HVECU 100 as a first control unit requests the engine ECU 200 as a second control unit to execute throttle feedback control that feedback controls the opening of the throttle valve 25 so that the output torque of the engine 2 becomes the target torque Te* corresponding to the target power Pe*, in accordance with the state of the hybrid vehicle 1. Then, the engine ECU 200 executes the throttle feedback control in response to the request from the HVECU 100.

[0035] In this embodiment, the throttle feedback control calculates a feedback amount for matching the output torque of the engine 2 derived by the HVECU 100 with the output torque of the engine 2 estimated by the engine ECU 200, and reflects the calculated feedback amount in the target opening of the throttle valve 25. Therefore, when the throttle feedback control is executed by the engine ECU 200, the HVECU 100 converts a torque command Tm1* corresponding to the output torque of the motor generator MG1 connected to the crankshaft 22 via the planetary gear 3 into the output torque of the engine 2 based on the gear ratio of the planetary gear 3 and the like, and transmits the derived output torque to the engine ECU 200. Furthermore, the engine ECU 200 estimates the output torque of the engine 2 based on the target power Pe* from the HVECU 100, the rotation speed Ne of the engine 2, and the like. Note that the output torque of the engine 2 used to calculate the feedback amount may be derived by an electronic control device other than the HVECU 100 (for example, the MGECU 600).

[0036] Fig. 4 is a flowchart showing an example of a routine executed by the HVECU 100 as the first control unit to determine whether or not throttle feedback control needs to be performed. The routine of Fig. 4 is executed by the HVECU 100 at predetermined time intervals (very short time intervals) when the hybrid vehicle 1 is in system startup and the HVECU 100 has not requested the execution of throttle feedback control. When the timing to execute the routine of Fig. 4 arrives, the HVECU 100 acquires information necessary for determining whether or not throttle feedback control needs to be performed, such as a separately set target power Pe*, the SOC, allowable charging power Win, and battery temperature Tb of the battery 5 transmitted from the battery ECU 500, and the intake air temperature Ta of the engine 2 transmitted from the engine ECU 200 (step S100).

[0037] After the process of step S100, the HVECU 100 determines whether the acquired target power Pe* is equal to or less than a predetermined relatively small required execution power P1 (for example, several kW) (step S110). If it is determined that the target power Pe* exceeds the required execution power P1 (step S110: NO), the HVECU 100 determines that the load on the engine 2 is relatively high, and transmits a signal indicating that execution of throttle feedback control is unnecessary and that execution of partial cylinder fuel cut control is permitted to the engine ECU 200 (step S105), and temporarily ends the routine of FIG.

[0038] Furthermore, when it is determined that the target power Pe* is equal to or less than the execution required power P1 (step S110: YES), the HVECU 100 determines whether the SOC of the battery 5 is equal to or less than a predetermined execution required value S1 (for example, a value around 50%) (step S120). When it is determined that the SOC of the battery 5 is greater than the execution required value S1 (step S120: NO), the HVECU 100 determines that there is no risk of a sudden decrease in the SOC of the battery 5, and transmits a signal indicating that execution of throttle feedback control is unnecessary and that execution of partial cylinder fuel cut control is permitted to the engine ECU 200 (step S105), and temporarily ends the routine of FIG.

[0039] Furthermore, when it is determined that the SOC of the battery 5 is equal to or lower than the execution request value S1 (step S120: YES), the HVECU 100 determines whether the intake air temperature Ta of the engine 2 is equal to or lower than a predetermined execution request intake air temperature Ta1 (for example, a temperature around 0° C.) (step S130). When it is determined that the intake air temperature Ta is higher than the execution request intake air temperature Ta1 (step S130: NO), the HVECU 100 determines that the environment around the hybrid vehicle 1 is not a low temperature environment, and transmits a signal indicating that execution of throttle feedback control is unnecessary and that execution of partial cylinder fuel cut control is permitted to the engine ECU 200 (step S105), and temporarily ends the routine of FIG.

[0040] Furthermore, when it is determined that the intake air temperature Ta is equal to or lower than the execution request intake air temperature Ta1 (step S130: YES), the HVECU 100 determines whether the battery temperature Tb of the battery 5 is equal to or lower than a predetermined execution request battery temperature Tb1 (for example, a temperature of around −10° C.) (step S140).When it is determined that the battery temperature Tb is higher than the execution request battery temperature Tb1 (step S140: NO), the HVECU 100 determines that there is no risk of a sudden decrease in the SOC of the battery 5, and transmits a signal indicating that execution of throttle feedback control is unnecessary and that execution of partial cylinder fuel cut control is permitted to the engine ECU 200 (step S105), and temporarily ends the routine of FIG.

[0041] Furthermore, when it is determined that battery temperature Tb is equal to or lower than execution required battery temperature Tb1 (step S140: YES), HVECU 100 determines whether allowable charging power Win of battery 5 is equal to or higher than a predetermined execution required power W1 (for example, minus several kW) (step S150). When it is determined that allowable charging power Win is less than execution required power W1 (step S150: NO), HVECU 100 determines that allowable charging power Win is not significantly limited, and transmits a signal to engine ECU 200 indicating that execution of throttle feedback control is unnecessary and that execution of partial cylinder fuel cut control is permitted (step S105), and temporarily ends the routine of FIG.

[0042] On the other hand, when it is determined that the allowable charging power Win is equal to or greater than the execution required power W1 (step S150: YES), the HVECU 100 determines that the load on the engine 2 is low and that the engine 2 and the battery 5 are in a low-temperature environment, and transmits a signal to the engine ECU 200 requesting execution of throttle feedback control and indicating that execution of partial cylinder fuel cut control is prohibited (step S160), and temporarily ends the routine of Fig. 4. That is, the HVECU 100 requests execution of throttle feedback control when the target power Pe* of the engine 2, the state of the engine 2, and the state of the battery 5 each satisfy predetermined conditions (when Pe* ≤ P1, SOC ≤ S1, Ta ≤ Ta1, Tb ≤ Tb1, and Win ≥ W1).

[0043] After requesting engine ECU 200 to execute throttle feedback control in step S160 of Fig. 4, HVECU 100 executes a routine shown in Fig. 5 at predetermined time intervals (very short time intervals) to determine whether or not to stop throttle feedback control. When the timing to execute the routine of Fig. 5 arrives, HVECU 100 acquires information necessary for determining whether or not to stop throttle feedback control, such as separately set target power Pe*, SOC, allowable charging power Win, and battery temperature Tb of battery 5 transmitted from battery ECU 500, and intake air temperature Ta of engine 2 transmitted from engine ECU 200 (step S200).

[0044] After the process of step S200, the HVECU 100 determines whether the acquired target power Pe* is less than a predetermined request cancellation power P2 that is greater than the execution request power P1 by, for example, about 1 to 3 kW (step S210). If it is determined that the target power Pe* is equal to or greater than the request cancellation power P2 (step S210: NO), the HVECU 100 determines that throttle feedback control is no longer necessary due to an increase in the load on the engine 2, and transmits a signal to the engine ECU 200 requesting that the throttle feedback control be stopped and indicating that execution of partial cylinder fuel cut control is permitted (step S205), and then ends the routine of FIG.

[0045] Furthermore, when it is determined that the target power Pe* is less than the request cancellation power P2 (step S210: YES), the HVECU 100 determines whether the SOC of the battery 5 is less than a predetermined request cancellation value S2 that is higher than the execution request value S1 by, for example, about 5% (step S220).When it is determined that the SOC of the battery 5 is equal to or greater than the request cancellation value S2 (step S220: NO), the HVECU 100 determines that the throttle feedback control is no longer necessary due to the recovery of the SOC, and transmits a signal to the engine ECU 200 requesting that the execution of the throttle feedback control be stopped and indicating that the execution of the partial cylinder fuel cut control is permitted (step S205), and ends the routine of FIG.

[0046] Furthermore, when it is determined that the SOC of the battery 5 is less than the request cancellation value S2 (step S220: YES), the HVECU 100 determines whether the intake air temperature Ta of the engine 2 is less than a predetermined request cancellation intake air temperature Ta2 that is higher than the execution request intake air temperature Ta1 by, for example, about 10° C. (step S230). When it is determined that the intake air temperature Ta is equal to or higher than the request cancellation intake air temperature Ta2 (step S230: NO), the HVECU 100 determines that the environment around the hybrid vehicle 1 is no longer a low-temperature environment, and transmits a signal to the engine ECU 200 requesting that the execution of the throttle feedback control be stopped and indicating that the execution of the partial-cylinder fuel cut control is permitted (step S205), and ends the routine of FIG.

[0047] Furthermore, when it is determined that the intake air temperature Ta is less than the request cancellation intake air temperature Ta2 (step S230: YES), the HVECU 100 determines whether the battery temperature Tb of the battery 5 is less than a predetermined request cancellation battery temperature Tb2 that is higher than the execution request battery temperature Tb1 by, for example, several degrees Celsius (step S240).When it is determined that the battery temperature Tb is equal to or higher than the request cancellation battery temperature Tb2 (step S240: NO), the HVECU 100 determines that there is no longer a risk of a sudden decrease in the SOC of the battery 5, and transmits a signal to the engine ECU 200 requesting that the execution of the throttle feedback control be stopped and indicating that the execution of the partial cylinder fuel cut control is permitted (step S205), and then ends the routine of FIG.

[0048] Furthermore, when it is determined that the battery temperature Tb is lower than the request cancellation battery temperature Tb2 (step S240: YES), the HVECU 100 determines whether the allowable charging power Win of the battery 5 exceeds a predetermined request cancellation power W2 that is smaller (has a larger absolute value) than the execution request power W1, for example, by several kW (step S250). When it is determined that the allowable charging power Win is equal to or smaller than the request cancellation power W2 (step S250: NO), the HVECU 100 determines that the allowable charging power Win is no longer significantly limited, and transmits a signal to the engine ECU 200 requesting that the throttle feedback control be stopped and indicating that the execution of the partial cylinder fuel cut control is permitted (step S205), and then ends the routine of FIG.

[0049] On the other hand, if it is determined that the allowable charging power Win exceeds the request cancellation power W2 (step S250: YES), the HVECU 100 determines that the load on the engine 2 is still low and that the engine 2 and the battery 5 are in a low-temperature environment, and transmits a signal to the engine ECU 200 requesting the execution of throttle feedback control and prohibiting the execution of the partial-cylinder fuel cut control (step S260), and temporarily ends the routine of FIG. 5.

[0050] As described above, in hybrid vehicle 1, hysteresis is set in the criteria for determining whether or not throttle feedback control is required. That is, a predetermined difference (hysteresis difference) for forming a dead band is provided between execution request power P1 and request cancellation power P2, each of which is compared with target power Pe*; between execution request value S1 and request cancellation value S2, each of which is compared with SOC of battery 5; between execution request intake air temperature Ta1 and request cancellation intake air temperature Ta2, each of which is compared with intake air temperature Ta of engine 2; between execution request battery temperature Tb1 and request cancellation battery temperature Tb2, each of which is compared with battery temperature Tb of battery 5; and between execution request power W1 and request cancellation power W2, each of which is compared with allowable charging power Win of battery 5. This effectively prevents frequent switching between requesting throttle feedback control (step S160 in FIG. 4) and canceling the request (step S205 in FIG. 5).

[0051] Next, a procedure for determining whether or not to execute fuel cut control for some cylinders by engine ECU 200 will be described with reference to Fig. 6. Fig. 6 is a flowchart showing a routine executed by engine ECU 200 at predetermined time intervals (very short time intervals) to determine whether or not to execute fuel cut control for some cylinders when engine 2 is operated under load at a predetermined rotation speed Nref (for example, a rotation speed of about 2000-3000 rpm) or higher in response to depression of the accelerator pedal by the driver, a request to charge battery 5, or the like.

[0052] 6, the engine ECU 200 acquires information necessary for the determination, such as the temperature Tpf of the particulate filter PF of the downstream purification device 32, the particulate matter accumulation amount Dpm on the particulate filter PF, and a partial cylinder fuel cut execution flag (step S300). The temperature Tpf of the particulate filter PF may be estimated separately by the engine ECU 200 based on the intake air amount QA, the rotation speed Ne, the exhaust gas temperature Teg, the upstream air-fuel ratio AFf, the downstream air-fuel ratio AFr, etc., or may be actually measured by a temperature sensor (not shown). The particulate matter accumulation amount Dpm is calculated (estimated) separately by the engine ECU 200 at predetermined time intervals using, for example, either a well-known operating history method or a differential pressure method depending on the operating state of the engine 2. The partial cylinder fuel cut execution flag is turned on when partial cylinder fuel cut control should be executed, and is turned off when partial cylinder fuel cut control should not be executed.

[0053] After the process of step S300, the engine ECU 200 determines whether the execution of throttle feedback control has been requested by the HVECU 100 and whether the execution of partial cylinder fuel cut control has been prohibited (step S310). If it is determined that the execution of throttle feedback control has not been requested by the HVECU 100 (step S310: NO), the engine ECU 200 turns off the partial cylinder fuel cut prohibition flag to permit the execution of partial cylinder fuel cut control (step S320), and determines whether a temperature increase of the downstream purification device 32 (and the upstream purification device 31), i.e., a regeneration of the particulate filter PF, has been requested (step S330).

[0054] In step S330, if the partial cylinder fuel cut execution flag is turned off and partial cylinder fuel cut control is not being executed, the engine ECU 200 determines whether the deposition amount Dpm acquired in step S300 is equal to or greater than a predetermined threshold value D1 (e.g., a value of about 5000 mg). Also, in step S330, if the engine ECU 200 determines that the deposition amount Dpm is equal to or greater than threshold value D1, the engine ECU 200 determines whether the temperature Tpf of the particulate filter PF acquired in step S300 is less than a predetermined temperature rise control start temperature Tx (e.g., a temperature of about 600°C). Furthermore, in step S330, if the partial cylinder fuel cut execution flag is turned on and partial cylinder fuel cut control is already being executed, the engine ECU 200 determines whether the deposition amount Dpm acquired in step S300 is equal to or less than a threshold value D0 (e.g., a value of about 3000 mg) that is predetermined smaller than the threshold value D1.

[0055] When the partial cylinder fuel cut control is not being executed and the deposition amount Dpm is less than the threshold D1, the engine ECU 200 determines that a temperature increase of the downstream side purification device 32 (and the upstream side purification device 31), i.e., regeneration of the particulate filter PF, is not required (step S340: NO). Also, even if the deposition amount Dpm is equal to or greater than the threshold D1, when the temperature Tpf of the particulate filter PF is equal to or less than the temperature increase control start temperature Tx, the engine ECU 200 determines that a further temperature increase of the downstream side purification device 32 (and the upstream side purification device 31) is not required (step S340: NO). Furthermore, when the partial cylinder fuel cut control has already been executed and the deposition amount Dpm is equal to or less than the threshold D0, the engine ECU 200 determines that the regeneration of the particulate filter PF has been completed and a further temperature increase of the downstream side purification device 32 (and the upstream side purification device 31) is not required (step S340: NO). If the engine ECU 200 determines that the temperature of the downstream purification device 32 is not required to be increased (step S340: NO), it turns off the partial cylinder fuel cut execution flag (step S380) to stop the execution of the partial cylinder fuel cut control, and temporarily terminates the routine of Figure 6.

[0056] Furthermore, when the partial cylinder fuel cut control is not being executed, the deposition amount Dpm is equal to or greater than the threshold value D1, and the temperature Tpf of the particulate filter PF is less than the temperature increase control start temperature Tx, the engine ECU 200 determines that a temperature increase of the downstream purification device 32 through the partial cylinder fuel cut control is required (step S340: YES). Furthermore, when the partial cylinder fuel cut control is being executed and the deposition amount Dpm is greater than the threshold value D0, the engine ECU 200 determines that regeneration of the particulate filter PF has not been completed, and that a temperature increase of the downstream purification device 32 through the partial cylinder fuel cut control is still required (step S340: YES). When the engine ECU 200 determines that a temperature increase of the downstream purification device 32 is required (step S340: YES), the engine ECU 200 turns on a partial cylinder fuel cut execution flag to execute the partial cylinder fuel cut control (step S350), and temporarily ends the routine of FIG. 6. When the partial cylinder fuel cut execution flag is turned on in step S350, engine ECU 200 checks other execution permission conditions as necessary and then executes partial cylinder fuel cut.

[0057] On the other hand, if the HVECU 100 requests execution of throttle feedback control and determines that execution of the partial cylinder fuel cut control is prohibited (step S310: YES), the engine ECU 200 turns on a partial cylinder fuel cut prohibition flag to prohibit execution of the partial cylinder fuel cut control (step S360). Furthermore, the engine ECU 200 determines whether the partial cylinder fuel cut execution flag is on (step S370). If the engine ECU 200 determines that the partial cylinder fuel cut execution flag is on (step S370: YES), the engine ECU 200 turns off the partial cylinder fuel cut execution flag to stop execution of the partial cylinder fuel cut control (step S380), and temporarily ends the routine of FIG. 6. If the partial cylinder fuel cut execution flag is turned off in step S380 while the partial cylinder fuel cut control is being executed, the engine ECU 200 stops execution of the partial cylinder fuel cut control. On the other hand, if it is determined that the partial cylinder fuel cut execution flag is off (step S370: NO), engine ECU 200 skips the process of step S380 and temporarily ends the routine of FIG.

[0058] As described above, hybrid vehicle 1 includes HVECU 100 (first control unit) and engine ECU 200 (second control unit) that cooperate to control hybrid vehicle 1. HVECU 100 sets a target power Pe* for engine 2 and requests execution of throttle feedback control that feedback-controls the opening of throttle valve 25 so that the output torque of engine 2 becomes a target torque Te* corresponding to the target power Pe*, depending on the states of engine 2 and battery 5 (vehicle state) (step S160 in FIG. 5). Furthermore, engine ECU 200 performs throttle feedback control in response to the request from HVECU 100. Furthermore, when a temperature increase of the downstream purification device 32, i.e., a regeneration of the particulate filter PF, is requested during load operation of the engine 2 (step S340: YES in FIG. 6), the engine ECU 200 executes partial cylinder fuel cut control to stop fuel supply to at least one cylinder (step S350 in FIG. 6) on the condition that throttle feedback control is not being executed (step S310: NO in FIG. 6).

[0059] As a result, when throttle feedback control is executed in a low-temperature environment where the intake air temperature Ta is equal to or lower than the execution-requested intake air temperature Ta1 and the battery temperature Tb is equal to or lower than the execution-requested battery temperature Tb1, the partial-cylinder fuel cut control is not executed. Therefore, when the hybrid vehicle 1 is in the low-temperature environment, the throttle feedback control can accurately bring the output torque of the engine 2 close to the target torque Te* corresponding to the target power Pe*. As a result, in a low-temperature environment, it is possible to raise the temperature of the downstream purification device 32 by executing the partial-cylinder fuel cut control while ensuring good controllability of the engine 2.

[0060] Furthermore, when the execution of throttle feedback control is requested by the HVECU 100 (step S310: YES in FIG. 6), the engine ECU 200 does not execute the partial cylinder fuel cut control (step S380 in FIG. 6), regardless of whether or not there is a request to increase the temperature of the downstream purification device 32. As a result, if the HVECU 100 sets hysteresis in the criteria for determining whether or not to execute throttle feedback control (see FIGS. 4 and 5), it becomes possible to effectively prevent the partial cylinder fuel cut control from being frequently switched between execution and suspension.

[0061] Furthermore, in the hybrid vehicle 1, a motor generator MG1 is coupled to the crankshaft 22 of the engine 2 via a planetary gear 3, and the HVECU 100 derives the output torque of the engine 2 based on a torque command Tm1* corresponding to the output torque of the motor generator MG1. The engine ECU 200 estimates the output torque of the engine 2 based on the target power Pe*, the rotation speed Ne, and the like. Furthermore, when executing throttle feedback control, the engine ECU 200 calculates a feedback amount for matching the estimated output torque of the engine 2 with the output torque of the engine 2 derived by the HVECU 100. This allows the HVECU 100 to accurately derive the output torque of the engine 2, and by stopping the execution of the partial cylinder fuel cut control, it is possible to ensure good accuracy in estimating the output torque of the engine 2 by the engine ECU 200 during execution of the throttle feedback control. Therefore, the throttle feedback control makes it possible to accurately bring the output torque of the engine 2 close to the target torque Te* corresponding to the target power Pe*.

[0062] Furthermore, the HVECU 100 sets the target power Pe* based on the required traveling power Pd* required for traveling of the hybrid vehicle 1 and the target charge / discharge power Pb* of the battery 5. When the engine ECU 200 executes the partial cylinder fuel cut control, the HVECU 100 increases the target power Pe* corresponding to the same accelerator opening Acc and vehicle speed V compared to when the partial cylinder fuel cut control is not executed. This makes it possible to suppress a decrease in the output torque of the engine 2 when the partial cylinder fuel cut control is executed. In addition, by stopping (prohibiting) the execution of the partial cylinder fuel cut control during execution of the throttle feedback control, it is possible to suppress a deterioration in the accuracy of the estimation of the output torque of the engine 2 by the engine ECU 200 and a deviation between the output torque of the engine 2 derived by the HVECU 100 and the output torque of the engine 2 estimated by the engine ECU 200. As a result, it becomes possible to accurately bring the output torque of the engine 2 close to the target torque Te* corresponding to the target power Pe* through the throttle feedback control.

[0063] Furthermore, when the target power Pe*, the state of the engine 2 (intake air temperature Ta), and the state of the battery 5 (SOC, allowable charging power Win, and battery temperature Tb) each satisfy a predetermined condition (step S150 in FIG. 4: YES), the HVECU 100 requests execution of throttle feedback control (step S160 in FIG. 4). This makes it possible to execute throttle feedback control at an appropriate timing.

[0064] Furthermore, the downstream purification device 32 of the hybrid vehicle 1 includes a particulate filter PF that captures particulate matter in the exhaust gas from the engine 2, and a temperature increase of the downstream purification device 32 is requested when it is necessary to regenerate the particulate filter PF (steps S330, S340: YES). This allows a large amount of oxygen (air) to be introduced into the particulate filter PF, which has been heated from some of the combustion chambers 20 to which fuel supply has been stopped due to the execution of the partial cylinder fuel cut control, thereby enabling the particulate matter deposited on the particulate filter PF to be burned well.

[0065] 4 and 5 and engine ECU 200 that executes the process of FIG. 6 can be applied to hybrid vehicles other than the hybrid vehicle 1 described above, which includes motor generators MG1, MG2 and planetary gear 3. That is, the hybrid vehicle to which HVECU 100 and engine ECU 200 are applied may be a one-motor or two-motor hybrid vehicle, or a series hybrid vehicle, as long as it includes an electric motor mechanically coupled to the crankshaft of the engine. Furthermore, the hybrid vehicle to which HVECU 100 and engine ECU 200 are applied may be a plug-in hybrid vehicle (PHEV).

[0066] As described above, the control device for a hybrid vehicle according to the present disclosure is a control device for a hybrid vehicle (1) including a multi-cylinder engine (2) having a throttle valve (25), an exhaust gas purification device (32) that purifies exhaust gas from the multi-cylinder engine (2), an electric motor (MG1) that can generate electricity using at least a part of the power from the multi-cylinder engine (2), and an electricity storage device (5) that exchanges electric power with the electric motor (MG1), and the control device sets a target power (Pe*) for the multi-cylinder engine (2), and adjusts the output torque of the multi-cylinder engine (2) to a target torque (Te*) corresponding to the target power (Pe*) according to a vehicle state. and a second control unit (200) that executes the throttle feedback control in response to the request from the first control unit (100) and, when a temperature increase of the exhaust gas purification device (32) is requested during load operation of the multi-cylinder engine (2) (S340: YES), executes a partial cylinder fuel cut control that stops fuel supply to at least one cylinder (20) on condition that the throttle feedback control is not being executed (S310: NO).

[0067] The control device for a hybrid vehicle disclosed herein includes first and second control units. The first control unit sets a target power for a multi-cylinder engine and requests execution of throttle feedback control, which feedback-controls the throttle valve opening so that the output torque of the multi-cylinder engine reaches a target torque corresponding to the target power, depending on the vehicle condition. The second control unit executes throttle feedback control in response to the request from the first control unit. Furthermore, when a temperature increase of an exhaust gas purification device is requested during load operation of the multi-cylinder engine, the second control unit executes partial-cylinder fuel cut control, which stops fuel supply to at least one cylinder, on the condition that throttle feedback control is not being executed. As a result, when throttle feedback control is executed in a low-temperature environment, partial-cylinder fuel cut control is not executed, so that the output torque of the multi-cylinder engine can accurately approach the target torque corresponding to the target power through throttle feedback control. As a result, it is possible to increase the temperature of the exhaust gas purification device by executing partial-cylinder fuel cut control while maintaining good controllability of the multi-cylinder engine in a low-temperature environment.

[0068] Furthermore, when the first control unit (100) requests the execution of the throttle feedback control (S310: YES), the second control unit (200) may not execute the partial cylinder fuel cut control (S380), regardless of whether or not there is a request to increase the temperature of the exhaust gas purification device (32). Thus, if the first control unit sets hysteresis in the criterion for determining whether or not to execute the throttle feedback control, it is possible to effectively prevent the partial cylinder fuel cut control from being frequently switched between execution and suspension.

[0069] Furthermore, the electric motor (MG1) may be coupled to the output shaft (22) of the multi-cylinder engine (2), the first control unit (100) may derive the output torque of the multi-cylinder engine (2) based on the output torque of the electric motor (MG1), and the second control unit (200) may estimate the output torque of the multi-cylinder engine (2) based on predetermined parameters and calculate a feedback amount for matching the estimated output torque with the output torque derived by the first control unit (100). This allows the first control unit to accurately derive the output torque of the multi-cylinder engine, and by stopping the execution of partial-cylinder fuel cut control, the accuracy of the estimation of the output torque by the second control unit during the execution of throttle feedback control can be ensured. Therefore, the throttle feedback control makes it possible to accurately bring the output torque of the multi-cylinder engine closer to the target torque corresponding to the target power.

[0070] Furthermore, the first control unit (100) may set the target power (Pe*) based on the power (Pd*) required for running the hybrid vehicle (1) and the target charge / discharge power (Pb*) of the power storage device (5), and may set the target power (Pe*) larger when the partial cylinder fuel cut control is executed by the second control unit (200) than when the partial cylinder fuel cut control is not executed. This suppresses a decrease in the output torque of the multi-cylinder engine when the partial cylinder fuel cut control is executed, and by stopping (prohibiting) the execution of the partial cylinder fuel cut control during the execution of throttle feedback control, it becomes possible to accurately bring the output torque of the multi-cylinder engine closer to the target torque corresponding to the target power by throttle feedback control.

[0071] Furthermore, the first control section (100) may request execution of the throttle feedback control (S160) when the target power (Pe*), the state of the multi-cylinder engine (2), and the state of the electricity storage device (5) each satisfy predetermined conditions (S150: YES), thereby making it possible to execute the throttle feedback control at an appropriate timing.

[0072] Furthermore, the exhaust gas purification device (32) may include a particulate filter (PF) that traps particulate matter in the exhaust gas from the multi-cylinder engine (2), and the temperature increase of the exhaust gas purification device (32) may be requested when it is necessary to regenerate the particulate filter (PF) (S340: YES). This allows a large amount of oxygen to be introduced into the particulate filter that has been heated by some of the cylinders to which fuel supply has been stopped due to the execution of the partial-cylinder fuel cut control, thereby enabling the particulate matter deposited on the particulate filter to be burned effectively.

[0073] The control method for a hybrid vehicle of the present disclosure is a control method for a hybrid vehicle (1) including a multi-cylinder engine (2) having a throttle valve (25), an exhaust gas purification device (32) that purifies exhaust gas from the multi-cylinder engine (2), an electric motor (MG1) that can generate electricity using at least a part of the power from the multi-cylinder engine (2), and an electricity storage device (5) that exchanges electric power with the electric motor (MG1), in which, when throttle feedback control is being executed that feedback controls the opening of the throttle valve (25) so that the output torque of the multi-cylinder engine (2) becomes a target torque (Te*), execution of partial cylinder fuel cut control that stops fuel supply to at least one cylinder (20) of the multi-cylinder engine (2) is prohibited (S310: YES, S360-S380).

[0074] According to this method, it is possible to raise the temperature of the exhaust gas purification device by executing fuel cut control for some cylinders while ensuring good controllability of a multi-cylinder engine in a low-temperature environment.

[0075] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present disclosure. Furthermore, the above-described embodiment is merely a specific form of the invention described in the Summary of the Invention, and does not limit the elements of the invention described in the Summary of the Invention. [Industrial Applicability]

[0076] The invention of the present disclosure can be used in the hybrid vehicle manufacturing industry and the like. [Explanation of symbols]

[0077] 1 hybrid vehicle, 2 engine (multiple cylinder engine), 3 planetary gear, 5 battery (electricity storage device), 5t battery temperature sensor, 20 combustion chamber (cylinder), 22 crankshaft, 22a crank angle sensor, 24t intake air temperature sensor, 25 throttle valve, 25o throttle opening sensor, 30 exhaust pipe, 31 upstream purification device, 32 downstream purification device, 90 vehicle speed sensor, 91 accelerator pedal position sensor, 100 hybrid electronic control unit (HVECU: first control unit), 200 engine electronic control unit (engine ECU: second control unit), MG1, MG2 motor generators.

Claims

1. A control device for a hybrid vehicle including a multi-cylinder engine having a throttle valve, an exhaust gas purification device that purifies exhaust gas from the multi-cylinder engine, an electric motor that can generate electricity using at least a portion of the power from the multi-cylinder engine, and an electricity storage device that exchanges electric power with the electric motor, a first control unit that sets a target power of the multi-cylinder engine and requests execution of throttle feedback control that feedback controls an opening of the throttle valve in accordance with a vehicle state so that an output torque of the multi-cylinder engine becomes a target torque corresponding to the target power; a second control unit that executes the throttle feedback control in response to a request from the first control unit, and that executes a partial cylinder fuel cut control that stops fuel supply to at least one cylinder when a temperature increase of the exhaust gas purification device is requested during load operation of the multiple cylinder engine, on condition that the throttle feedback control is not being executed; A control device for a hybrid vehicle comprising:

2. 2. The control device for a hybrid vehicle according to claim 1, A control device for a hybrid vehicle, wherein the second control unit does not execute the fuel cut control for some cylinders when the first control unit requests the execution of the throttle feedback control, regardless of whether or not there is a request to increase the temperature of the exhaust gas purification device.

3. 3. The hybrid vehicle control device according to claim 1, the electric motor is connected to an output shaft of the multi-cylinder engine; the first control unit derives an output torque of the multi-cylinder engine based on an output torque of the electric motor; The second control unit estimates the output torque of the multi-cylinder engine based on predetermined parameters, and calculates a feedback amount to match the estimated output torque with the output torque derived by the first control unit.

4. 3. The hybrid vehicle control device according to claim 1, The first control unit sets the target power based on the power required for running the hybrid vehicle and the target charge / discharge power of the power storage device, and when the partial cylinder fuel cut control is executed by the second control unit, the target power is increased compared to when the partial cylinder fuel cut control is not executed.

5. 3. The hybrid vehicle control device according to claim 1, The first control unit is a control device for a hybrid vehicle that requests execution of the throttle feedback control when the target power, the state of the multi-cylinder engine, and the state of the power storage device each satisfy predetermined conditions.

6. 3. The hybrid vehicle control device according to claim 1, the exhaust gas purification device includes a particulate filter that collects particulate matter in exhaust gas from the multiple-cylinder engine, A control device for a hybrid vehicle, wherein the temperature increase of the exhaust gas purification device is required when the particulate filter needs to be regenerated.

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