JP2017171192A - Control device of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a hybrid vehicle which suppresses the consumption of a battery when compensating for a lowering amount of an output of an internal combustion engine caused by the ignition retardation of a cylinder at the warmup of a catalyst by an output of an electric motor.SOLUTION: When switching a cylinder operation to a full-cylinder operation in which resting cylinders 33, 36 are brought into operation states from a reduced-cylinder operation in which the resting cylinders 33, 36 are brought into non-operation states, an ECU 19 performs first control for retarding the ignition timing of the resting cylinders 33, 36 when a second catalyst 57 arranged in an exhaust pipe 56 connected to the resting cylinders 33, 36 does not reach a prescribed temperature. Furthermore, the CPU performs second control for making a second motor 13 output a traveling drive force during the execution of the first control. When the ECU 19 performs the first control or the second control, the ECU sets the ignition timing of the resting cylinders 33, 36 at timing at which an amount for displacing the ignition timing to a retardation side with respect to the ignition timing of operating cylinders 34, 35 becomes large as a battery residual amount which is detected by a power supply part 21 becomes small.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a control device for a hybrid vehicle that uses a driving force output from one or both of an internal combustion engine and an electric motor as a driving force for traveling, and more particularly, among multi-cylinders included in an internal combustion engine. The present invention relates to a control device for a hybrid vehicle that performs a reduced-cylinder operation in which a specific cylinder is deactivated.

  Conventionally, a reduced cylinder operation in which a specific cylinder is deactivated according to the operating state of the internal combustion engine is performed, and the number of operating cylinders is reduced, so that the substantial exhaust amount of the internal combustion engine is temporarily reduced to improve fuel efficiency. Such an internal combustion engine is known (see, for example, Patent Document 1). For example, in the internal combustion engine described in Patent Document 1, a cylinder deactivation mechanism is provided in the right bank of the V-type six cylinders, the cylinders in the right bank are deactivated in accordance with the operating state, and only the cylinders in the left bank are operated. Do the driving. An independent exhaust pipe is connected to each of the right bank cylinder and the left bank cylinder. A catalyst for the right bank and a catalyst for the left bank for purifying the exhaust gas are placed in the middle of the two exhaust pipes. Each is provided.

  In the internal combustion engine, exhaust gas from the cylinders of each bank is exhausted through each exhaust pipe during all cylinder operation. As a result, the catalyst for the right bank and the catalyst for the left bank are warmed by the exhaust gas passing through the exhaust pipes, and the active state of the catalyst is maintained. However, during the reduced cylinder operation, the cylinders in the right bank are deactivated, and the exhaust gas does not pass through the catalyst for the right bank, so the temperature of the catalyst for the right bank decreases. In order to suppress such deterioration of exhaust emission, the internal combustion engine described in Patent Document 1 has the catalyst temperature for the right bank estimated by the catalyst temperature estimation means after the shift from the reduced cylinder operation to the all cylinder operation. Accordingly, the ignition timing in the idle cylinder is retarded with respect to the ignition timing in the operating cylinder.

JP-A-2005-351134

  As described above, for example, in order to raise the exhaust gas temperature in order to achieve early activation of the catalyst when the internal combustion engine is cold, catalyst warm-up operation that retards the ignition timing is known. If the angle is retarded, the combustion efficiency (actual engine torque) of the internal combustion engine decreases. For this reason, when the internal combustion engine is cold, for example, when the driver depresses the accelerator (power-on state), the target engine torque requested by the driver may not be output. Therefore, in a hybrid vehicle, it is conceivable to perform control for raising the actual engine torque to the target engine torque by compensating for the decrease in the actual engine torque with the torque output by the electric motor. However, if the power-on state is made when the remaining capacity of the battery that accumulates the electric power of the motor is small, the remaining capacity of the battery may fall below a threshold (charging threshold) that requires charging during the catalyst warm-up operation. There is. If it becomes like this, the drive of an electric motor must be stopped and the fall of an engine torque cannot be supplemented with the torque which an electric motor outputs.

  The present invention has been made paying attention to the above technical problem, and is a hybrid capable of suppressing battery consumption when the output of the internal combustion engine caused by the ignition delay of the cylinder is compensated by the output of the electric motor. An object of the present invention is to provide a vehicle control device.

  In order to achieve the above object, the present invention provides an internal combustion engine having an operating cylinder that is always operated during operation and a non-operating cylinder that is inactive, and an exhaust gas into which exhaust gas from the operating cylinder flows. An exhaust gas purifying unit having one catalyst and a second catalyst into which exhaust gas from the idle cylinder flows, a first detecting unit for detecting an estimated temperature of the second catalyst, and a function of generating electric power by a driving force output from the internal combustion engine When switching from a reduced-cylinder operation in which the deactivated cylinder is deactivated to an all-cylinder operation in which the deactivated cylinder is activated, the battery stores the electric power generated by the motor. And a control unit that performs first control for retarding the ignition timing of the idle cylinder when the estimated temperature of the second catalyst does not reach a predetermined temperature based on information obtained from one detection unit. The vehicle control device includes a second detection unit that detects a remaining capacity of the battery, and the control unit uses the electric power stored in the battery during the first control. When the second control for outputting the driving force for traveling is performed, and when the first control and the second control are performed, the rest of the battery detected by the second detection unit decreases, so that the pause The ignition timing in the cylinder is configured to be set to a timing when the amount of shifting to the retard side becomes larger than the ignition timing of the operating cylinder.

  In this invention, when the output reduction of the internal combustion engine caused by the ignition delay of the cylinder is compensated by the output of the electric motor, the ignition timing in the idle cylinder is delayed from the ignition timing of the operating cylinder as the remaining battery capacity decreases. It is configured to set at a time when the amount of shift to the corner side becomes large. As a result, the temperature of the catalyst is raised more quickly, so that the motor drive time for compensating for the decrease in the output of the internal combustion engine can be reduced, and thus battery consumption can be suppressed.

It is a block diagram which shows an example of the hybrid vehicle applied to this invention. It is explanatory drawing which shows the operation mode in the case of switching to all cylinder operation. It is a flowchart which shows control of ECU in the case of switching to all cylinder operation. It is a flowchart which shows the procedure of ECU which implements a catalyst warm-up mode. It is a time chart which shows operation | movement of each part in a catalyst warm-up mode. It is a time chart which shows operation | movement of each part in E / G retardation angle mode. It is explanatory drawing which shows the relationship between the engine torque with respect to ignition retard, and exhaust temperature. It is explanatory drawing which shows the relationship between the engine torque with respect to the opening degree of a throttle valve, and exhaust temperature.

  Embodiments will be described below with reference to the drawings. FIG. 1 shows an example of a drive device 10 used in a hybrid vehicle (hereinafter referred to as “vehicle”) 9 applied to the present invention. As shown in FIG. 1, the drive device 10 includes an engine 11, a first motor (MG1) 12, a second motor (MG2) 13, a power transmission mechanism 14, an output member (OUT) 15, and an ENG_ECU (Engine_Electronic Control Unit) 16. , MG (Motor Generator) _ECU 17, hydraulic control unit 18, ECU 19, battery 20, and power supply unit 21. The output member 15 is, for example, a gear example that transmits a driving force obtained by combining the driving force output from the power transmission mechanism 14 and the driving force output from the second motor 13 to the output shaft 22. The driving force output from the output shaft 22 is transmitted to the driving wheel 24 through the differential 23. The first motor 12 and the second motor 13 are constituted by a motor / generator having a power generation function. The engine 11 is an example of an internal combustion engine.

  The power transmission mechanism 14 is configured by, for example, a speed reduction mechanism and a power split mechanism. This power transmission mechanism 14 has a plurality of engagement mechanisms (all not shown) including, for example, a clutch mechanism and a brake mechanism, and the driving force output by the engine 11 by switching the engagement state of each engagement mechanism. Is divided into a driving force transmitted to the first motor 12 and a driving force transmitted to the output member 15. The engagement state of the engagement mechanism is switched by the hydraulic pressure supplied from the hydraulic control unit 18. The ECU 19 controls one of the plurality of travel modes including the hybrid travel mode by controlling the hydraulic pressure supply of the hydraulic pressure control unit 18 and implements it. In the hybrid travel mode, the first motor 12 is driven as a power generation function using a part of the driving force output from the engine 11, and the second motor 13 is driven using the power generated by the first motor 12. . In the hybrid travel mode, the vehicle travels by adding the driving force output from the second motor 13 to the driving force output from the engine 11. The second motor 13 is an example of an electric motor.

  The MG_ECU 17 comprehensively manages the first motor 12, the second motor 13, the battery 20, and the power supply unit 21. The ENG_ECU 16 controls the operating state of the engine 11. The ECU 19 controls the ENG_ECU 16, the MG_ECU 17, and the hydraulic control unit 18 so that the vehicle can operate most efficiently. The power supply unit 21 includes a converter 25 and an inverter 26. Converter 25 boosts the DC voltage and outputs it to inverter 26 in accordance with information output from ECU 19 including, for example, the rotational speed of the motor and target output torque (output torque command value). The inverter 26 converts the direct current output from the converter 25 into an alternating current for driving the second motor 13. Further, the inverter 26 converts, for example, the power generated by the first motor 12 into the charging power of the battery 20 during the regenerative operation of the vehicle 9. Power supply unit 21 calculates the state of charge of battery 20 (battery remaining capacity: SOC (State Of Charge)) based on the storage voltage and input / output current of battery 20, and outputs the calculated SOC to MG_ECU 17. The voltage and input / output current of the battery 20 are detected by a voltage sensor and a current sensor not shown, respectively. Alternatively, the voltage of battery 20 and the detected value of the input / output current may be output from battery 20 to MG_ECU 17 or ECU 19, and SOC may be calculated in MG_ECU 17 or ECU 19. The power supply unit 21 is an example of a second detection unit.

  The ENG_ECU 16 receives, for example, vehicle speed information sent by a vehicle speed sensor 27 that detects the rotational speed of the drive shaft, and position information sent by a position switch 28 provided on a shift lever (not shown). The ENG_ECU 16 also includes information on the accelerator opening sent from the accelerator opening sensor 29 provided on the accelerator pedal (not shown) and the depression of the brake pedal sent by the stroke sensor 30 provided on the brake pedal (not shown). Quantity information is entered. Further, the ENG_ECU 16 receives information on the engine speed sent from the engine speed sensor 32 provided in the engine 11.

  The engine 11 is a multi-cylinder engine having a first cylinder 33 to a fourth cylinder 36, and is an in-cylinder direct injection engine that supplies fuel directly into each cylinder separately from air. Fuel injection valves 37 to 40 for directly injecting fuel, for example, gasoline, are attached to the first cylinder 33 to the fourth cylinder 36. Spark plugs 41 to 44 are attached to the first cylinder 33 to the fourth cylinder 36. An igniter (not shown) is connected to the spark plugs 41 to 44. The igniter adjusts the ignition timing of the spark plugs 41 to 44. The ENG_ECU 16 controls the operation of the fuel injection valves 37 to 40 and the igniter. In this control, the amount of fuel injected from the fuel injection valves 37 to 40 and the control of the injection timing, and the timing (ignition timing) for performing ignition by the spark plugs 41 to 44 are determined from MBT (Minimum advance for Best Torque). In addition, it is possible to control the ignition delay that is shifted to the retard side. The MBT is the most retarded ignition timing at which the engine torque becomes maximum, that is, the optimal ignition timing when only the ignition timing is changed under the same operating conditions.

  For example, an intake manifold 45 including a plurality of intake branch pipes is connected to each intake valve of the first cylinder 33 to the fourth cylinder 36. The intake manifold 45 joins and is connected to one intake pipe 46. The intake pipe 46 is provided with an electronically controlled throttle valve 47. The throttle valve 47 is driven to open and close by an actuator 48. The drive of the actuator 48 is controlled by the ENG_ECU 16 via the driver 49. The throttle valve 47 changes the flow rate (intake amount) of air passing through the intake pipe 46 by a change in opening degree associated with the opening / closing operation. The throttle valve 47 is provided with an opening sensor 50 for detecting the opening amount. Information on the throttle opening (actual opening) detected by the opening sensor 50 is sent to the ENG_ECU 16. Further, the intake pipe 46 is provided with an airflow sensor 51 for detecting the intake air flow rate upstream of the throttle valve 47. Information on the intake air flow rate detected by the airflow sensor 51 is sent to the ENG_ECU 16.

  The ENG_ECU 16 obtains user request power required for driving required for the vehicle 9 in response to, for example, a state where the accelerator pedal is depressed (power-on state). For example, after determining the target output torque (drive shaft torque) of the output shaft 22 from parameters including the vehicle speed and the accelerator opening, the user request power is determined from, for example, a map according to the ratio of the engine speed and the vehicle speed. It is determined based on the calculated value and the target drive shaft torque.

  The ENG_ECU 16 obtains a base opening corresponding to the target throttle opening, for example, with reference to a map based on parameters including the user request power and the engine speed. For example, the map is a three-dimensional map created by measuring in advance the relationship between user required power, engine speed, and base opening. The ENG_ECU 16 obtains a target throttle opening that can suppress the exhaust emission deterioration by correcting the base opening, for example, with an opening correction amount corresponding to the catalyst temperature, for example. The ENG_ECU 16 calculates the control amount of the actuator 48 based on the calculated target throttle opening and the throttle opening at that time (actual throttle opening). Then, the ENG_ECU 16 outputs the calculated control amount to the driver 49, and the driver 49 drives the actuator 48.

  The ENG_ECU 16 obtains the target intake air amount and the target ignition timing with reference to, for example, a map based on the parameters including the user request power. The ENG_ECU 16 controls the opening degree of the throttle valve 47 by driving the actuator 48 via the driver 49 so as to realize the obtained target intake air amount. Further, the ENG_ECU 16 controls energization of the igniter based on the calculated target ignition timing. Furthermore, the ENG_ECU 16 accurately calculates the actual output torque of the engine 11 from the actual operating state of the engine 11, and achieves the target output torque so that the actual output torque accurately follows the target output torque.

  The ENG_ECU 16 selects and executes either one of a reduced-cylinder operation in which some cylinders are deactivated or an all-cylinder operation in which all cylinders are activated in accordance with the operation state of the vehicle 9. In the reduced-cylinder operation, for example, fuel supply and ignition are stopped for the first cylinder 33 and the fourth cylinder 36 so as to be inoperative, and the remaining second cylinder 34 and third cylinder 35 are activated. . In the all cylinder operation, the first cylinder 33 to the fourth cylinder 36 constituting all the cylinders are put into an operating state. Note that the first cylinder 33 and the fourth cylinder 36 are examples of idle cylinders, and the second cylinder 34 and the third cylinder 35 are examples of operating cylinders.

  An exhaust gas purification unit 53 is connected to the engine 11. The exhaust gas purification unit 53 includes a first catalyst 55 into which exhaust gas from the operating cylinders 34 and 35 flows through the first exhaust pipe 54 and a second catalyst 57 into which exhaust gas from the idle cylinders 33 and 36 flows through the second exhaust pipe 56. Have. The second exhaust pipe 56 is disposed on the outer peripheral side of the first exhaust pipe 54. That is, the second catalyst 57 is arranged to be heated by heat transfer from the first catalyst 55 in the inner peripheral portion. An exhaust temperature sensor 58 is attached to the second exhaust pipe 56. The exhaust temperature sensor 58 outputs an electrical signal corresponding to the temperature of the exhaust gas flowing through the second exhaust pipe 56 to the ENG_ECU 16. The ENG_ECU 16 estimates the temperature of the second catalyst 57 based on information obtained from the exhaust temperature sensor 58. The exhaust temperature sensor 58 is an example of a first detection unit.

  The ENG_ECU 16 performs control to switch the engine 11 from all-cylinder operation to reduced-cylinder operation when the load required by the user is less than a predetermined threshold, for example, when the vehicle 9 is stopped. Further, the ECU 19 uses the driving force output from the engine 11 to start the engine 11 when the user requested power is low and the SOC is less than a predetermined charging threshold. The charge control is performed to charge the battery 20 with the electric power generated by the rotated first motor 12. Further, when the SOC exceeds the charging threshold, the ECU 19 uses the charging power of the battery 20 to drive the second motor 13 and use the driving force output from the second motor 13 as the driving force for traveling. Allow motor assist control to be used.

  When the engine 11 is switched from the reduced-cylinder operation to the all-cylinder operation, the ENG_ECU 16 determines that the idle cylinder 33, when the temperature of the second catalyst 57 is lower than a predetermined threshold, that is, when the second catalyst 57 is lower than the activation temperature. A first control is performed in which the ignition timing 36 is retarded by a predetermined amount from the ignition timing (optimum ignition timing) of the operating cylinders 34 and 35. The ignition timing retarded in the first control is set within an emission establishment range in which the exhaust emission limitation can be observed. Further, when performing the first control, the ENG_ECU 16 performs the second control for outputting the driving force for compensating for the output shortage of the engine 11 from the second motor 13. The temperature of the second catalyst 57 is estimated based on information obtained from the exhaust temperature sensor 58. By retarding the ignition timing when the idle cylinders 33 and 36 are operated, the exhaust gas temperature can be raised at an early stage, for example, in order to activate the second catalyst 57 early.

  When performing the first control, the ENG_ECU 16 shifts the ignition timing in the combustion stroke of the idle cylinders 33 and 36 more retarded than the ignition timing retarded in the first control as the SOC decreases. The amount is controlled so as to be set at a time when it becomes large. Here, for example, “the smaller the SOC is” means that the chargeable capacity of the battery 20 is small in the non-charge capacity range where the SOC exceeds the charging threshold and charging is not necessary. In this embodiment, for example, the detection is performed by dividing into three regions, that is, a region having a relatively large remaining capacity in a non-charge capacity region, a region having a small remaining capacity, and an intermediate region therebetween. When it is included in the region where the SOC is low, the ignition timing is set at a time when the amount of shift from the ignition timing retarded in the first control to the retard side becomes larger than in the case where it is included in the region where the SOC is high. The In addition, when it is included in the region where the SOC is low, the ignition timing is set at a time when the amount of shift from the ignition timing retarded in the first control to the retard side is smaller than in the case where it is included in the region where the SOC is high. Is done. When the SOC is included in the intermediate region, the ignition timing is set to a timing at which the amount shifted from the ignition timing retarded in the first control to the retard side is a relatively intermediate amount. Although the retardation amount corresponding to the SOC is set in three stages, it is not limited to three stages and may be two stages or four or more stages.

  FIG. 2 is an explanatory diagram showing an operation mode selected based on the required load (user required power) of the vehicle 9 and the estimated temperature of the second catalyst 57 when switching from the reduced cylinder operation to the all cylinder operation. When the estimated temperature of the second catalyst 57 is relatively low and the required load of the vehicle 9 is low, the ECU 19 performs the catalyst warm-up mode.

  In the catalyst warm-up mode, the first control described above is performed, and the engine 11 is operated autonomously (no-load operation) at the idle rotation speed in a state where the retarded cylinders 33 and 36 perform the ignition retardation. Further, in the catalyst warm-up mode, the second control described above is performed when the insufficient power obtained by subtracting the engine power when the catalyst warm-up mode is performed from the user requested power is smaller than the upper limit output power of the second motor 13. carry out. The upper limit output power of the second motor 13 is set by the ECU 19 according to the state of the battery including the SOC. The ECU 19 adjusts the output of the second motor 13 below the output upper limit power. The ECU 19 ends the catalyst warm-up mode when the second catalyst 57 reaches the activation temperature.

  When the temperature of the second catalyst 57 is relatively low and the required load of the vehicle 9 is high, the ECU 19 performs the E / G retardation mode. In the E / G retarded angle mode, the first control described above is performed, and control is performed so that the opening degree of the throttle valve 47 is increased in a state in which the retarded cylinders 33 and 36 perform the retarded ignition. Further, in the E / G retard mode, the second power is obtained when the insufficient power obtained by subtracting the engine power when the E / G retard mode is performed from the user requested power is smaller than the upper limit output power of the second motor 13. Implement control. In this case, since the opening degree of the throttle valve 47 is set to be larger, the actual engine power becomes larger than that in the case where the catalyst warm-up mode is performed. The vehicle 9 travels by assisting the driving force output by the engine 11 with the driving force output by the second motor 13. In this case, the output of the second motor 13 may be smaller than when the catalyst warm-up mode is performed. The ECU 19 ends the E / G retardation mode when the second catalyst 57 reaches the activation temperature.

  When the temperature of the second catalyst 57 is relatively medium and the required load of the vehicle 9 is low, the ECU 19 performs the E / G retardation mode. When the temperature of the second catalyst 57 is relatively medium and the required load of the vehicle 9 is high, the ECU 19 performs the E / G retardation mode. When the temperature of the second catalyst 57 is relatively high and the required load of the vehicle 9 is relatively low, and when the temperature of the second catalyst 57 is relatively high and the required load of the vehicle 9 is relative In particular, the ECU 19 performs normal all-cylinder operation (normal mode) since there is no need for catalyst warm-up operation when the load is high.

  FIG. 3 is a flowchart showing a control procedure of the ECU 19 when switching from the reduced cylinder operation to the all cylinder operation. As shown in FIG. 3, in step S <b> 1, the ECU 19 obtains user request power (request load of the vehicle 9) based on the map using the engine speed and the engine torque as parameters. In step S2, the ECU 19 determines whether or not the user request power exceeds a predetermined threshold value. If affirmative (Y side), that is, if the user request power exceeds the threshold value, the process proceeds to step S3. In the case of negative (N side), the user request power is equal to or less than the threshold value, so the process proceeds to step S4 and the reduced cylinder operation is performed as it is.

  In step S <b> 3, the ECU 19 acquires the catalyst temperature, that is, the estimated temperature of the second catalyst 57 obtained from the exhaust temperature sensor 58. In step S <b> 5, the ECU 19 determines whether or not the acquired estimated temperature of the second catalyst 57 is lower than a predetermined threshold, that is, the activation temperature of the second catalyst 57. If the determination is affirmative (Y side), that is, if the temperature is lower than the activation temperature (the temperature of the second catalyst 57 corresponds to an intermediate temperature or a low temperature), the process proceeds to step S6. If the result is negative (N side) (the temperature of the second catalyst 57 is equivalent to the high temperature (activation temperature)), the process proceeds to step S7 and the normal mode of all cylinder operation is performed.

  In step S6, the ECU 19 determines whether or not the acquired estimated temperature of the second catalyst 57 is lower than a predetermined threshold value (activation temperature of the second catalyst 57). If the determination is affirmative (Y side), that is, if the temperature of the second catalyst 57 is low, the process proceeds to step S8. If negative (N side), that is, if the activation temperature is medium temperature, the process proceeds to step S9, and the E / G retardation mode is performed.

  In step S8, the ECU 19 acquires the upper limit output power of the second motor 13 based on the SOC at that time. In step S9, the ECU 19 determines whether or not the insufficient power obtained by subtracting the engine power when the catalyst warm-up mode is performed from the user requested power is less than the upper limit output power. If the determination is affirmative (Y side), that is, if the required load of the vehicle 9 is low, the ECU 19 proceeds to step S11 and performs the catalyst warm-up mode. In the case of negative (N side), that is, when the required load of the vehicle 9 is high, the ECU 19 proceeds to step S9 and implements the E / G retardation mode.

  FIG. 4 is a flowchart showing a control procedure of the ECU 19 that performs the catalyst warm-up mode. 4 that are the same as or similar to the processes described in FIG. 3 are assigned the same reference numerals, and detailed descriptions thereof are omitted. For example, the catalyst warm-up mode is characterized by processing performed in a range surrounded by a two-dot chain line in FIG. In step S13, the ECU 19 calculates the opening degree of the throttle valve 47 when the catalyst warm-up mode is performed within a range in which the exhaust emission deterioration can be suppressed based on the user requested power, and proceeds to step S14. Note that, in the catalyst warm-up mode, the throttle opening of the independent operation (no-load operation) is calculated. In step S14, the ECU 19 calculates the ignition timing in the operating cylinders 34 and 35 based on the calculated throttle opening so that MBT or TK (trace knock) can be obtained within a range in which exhaust emission deterioration can be suppressed. The process proceeds to step S15. In step S15, the ECU 19 acquires the SOC, and proceeds to step S16. In step S16, the ECU 19 calculates the ignition timing in the deactivated cylinders 33, 36 according to the SOC. The ignition timing in the deactivated cylinders 33, 36 calculated in step S16 is retarded by a predetermined amount (in the first control) than the ignition timing in the operating cylinders 34, 35 calculated in step S14. A timing for shifting to the retarded side is calculated in accordance with the SOC with respect to the retarded ignition timing. In step S16, the retard amount including the amount retarded in the first control and the amount retarded according to the SOC may be calculated.

  For example, in step S <b> 16, the ECU 19 retards the ignition timing with respect to the ignition timing retarded by the first control when it is included in the region where the SOC is low, compared to the case where it is included in the region where the SOC is high. The ignition timing is obtained so that the amount of shift is relatively large. In addition, when it is included in the region where the SOC is small, the amount by which the ignition timing is shifted to the retard side relative to the ignition timing retarded by the first control is relative to the case where it is included in the region where the SOC is large. The ignition timing is calculated so as to be less. When the SOC is included in the intermediate region, the amount by which the ignition timing is shifted to the retard side with respect to the ignition timing retarded by the first control is determined depending on whether the SOC is high or low. The ignition timing is calculated so that it is about the middle amount. In step S16, the ECU 19 calculates the ignition timing in the deactivated cylinders 33 and 36, and then proceeds to step S17. That is, when the SOC is small, the retard amount is increased to quickly raise the temperature of the second catalyst 57, and when the SOC is large, the retard amount is decreased to slowly raise the second catalyst 57. Let

  In step S <b> 17, the ECU 19 calculates the engine power when the catalyst warm-up mode is performed in consideration of the output decrease due to the ignition delay in the idle cylinders 33 and 36. When the catalyst warm-up mode is performed, for example, the engine power when the catalyst warm-up retarded combustion operation (self-supporting operation) for maintaining the engine 11 at the idling rotational speed is performed is calculated. In step S8, the ECU 19 acquires the upper limit output power based on the SOC at that time. In step S10, the ECU 19 determines whether or not the power obtained by subtracting the engine power in the catalyst warm-up mode from the user requested power is less than the upper limit output power. If the determination is affirmative (Y side), that is, if the required load of the vehicle 9 is high, the ECU 19 proceeds to step S18. In the case of negative (N side), that is, when the required load of the vehicle 9 is low, the ECU 19 proceeds to step S4 and maintains the reduced cylinder operation.

  In step S18, the ECU 19 sets the total power of the engine power considering the engine output reduction due to the ignition delay in the idle cylinders 33 and 36 and the power of the target second motor 13 to be the user-requested power. Then, the power of the target second motor 13 is calculated. In step S19, the ECU 19 instructs the ENG_ECU 16 the ignition timing calculated in step S16. In step S20, the ECU 19 instructs the MG_ECU 17 the target rotational speed and torque command value corresponding to the power of the second motor 13 calculated in step S18.

  The control procedure of the ECU 19 that implements the E / G retardation mode is the same as or similar to the control procedure that implements the catalyst warm-up mode described in FIG. The difference is that in step S13 described with reference to FIG. 4, the ECU 19 calculates the throttle opening when the E / G retardation mode is implemented. The value is calculated so that the opening degree of the throttle valve 47 at this time becomes large. In step S17, the ECU 19 calculates the engine power in the E / G retardation mode. For example, the ECU 19 calculates the engine power when performing the retarded combustion operation when the opening degree of the throttle valve 47 is set to be large.

  FIG. 5 is a time chart showing the operation of each part in the catalyst warm-up mode. As shown in FIG. 5, before the time t1, the reduced-cylinder operation is performed and the accelerator pedal is not depressed (the required load is low). At time t1, for example, a power-on state is established, and the user-requested power increases as indicated by symbol A in FIG. At this time, it is assumed that the insufficient power obtained by subtracting the engine power in the catalyst warm-up mode from the user requested power is less than the upper limit output power. In response to this, the ECU 19 starts the all-cylinder operation of the engine 11 and performs the catalyst warm-up mode. In the catalyst warm-up mode, as described above, the ignition delay is performed in the combustion stroke of the idle cylinders 33 and 36, and the catalyst warm-up retarded combustion operation (self-sustained operation) is performed in which the engine 11 is maintained at the idling speed. No-load operation is performed. Thus, since the engine 11 has an output corresponding to the idling rotation and the ignition delay is performed in the idle cylinders 33, 36, the idle cylinders 33, 36 are operated cylinders 34 as indicated by reference numeral B in FIG. , 35, the output is reduced. The output of the second motor 13 is increased as indicated by the symbol C in FIG. At time t2, as indicated by the symbol D in the figure, the second catalyst 57 reaches the activation temperature and the execution of the catalyst warm-up mode is stopped. That is, normal operation is performed from time t2, and the output of the idle cylinders 33 and 36 is increased as indicated by symbol E in the figure, and the output of the second motor 13 is correspondingly increased as indicated by symbol F in the figure. Is reduced.

  FIG. 6 is a time chart showing the operation of each part in the E / G retardation mode. As shown in FIG. 6, before the time t3, the reduced-cylinder operation is performed, and the power pedal is not turned on (the required load is low). At time t3 during the reduced cylinder operation, for example, a power-on state is established, and the user requested power is increased as indicated by reference numeral G in FIG. At this time, it is assumed that the insufficient power obtained by subtracting the engine power in the catalyst warm-up mode from the user requested power is equal to or higher than the upper limit output power. In response to this, the ECU 19 operates the idle cylinders 33 and 36 to start the full cylinder operation of the engine 11 and implements the E / G retardation mode. In the E / G retarded mode, ignition retarded control is performed in the idle cylinders 33 and 36 as described above, and retarded combustion operation is set so that the opening of the throttle valve 47 is increased. . Since the ignition delay is performed, the output of the idle cylinders 33 and 36 is lower than that of the operating cylinders 34 and 35 as indicated by the symbol H in FIG. Further, since the opening degree of the throttle valve 47 is set to be large, the output of the idle cylinders 33 and 36 is higher than that of the idle cylinders 33 and 36 in the catalyst warm-up mode described with reference to FIG. The output of the second motor 13 is increased by the amount corresponding to the decrease in the output of the idle cylinders 33 and 36 as compared with the operating cylinders 34 and 35, as indicated by the symbol I in FIG. The output of the second motor 13 in the E / G retardation mode is lower than that of the second motor 13 in the catalyst warm-up mode described with reference to FIG. At time t4, the second catalyst 57 reaches the activation temperature and the execution of the catalyst warm-up mode is stopped as indicated by the symbol J in FIG. That is, normal operation is performed from time t4. When the operation is switched to the normal operation, the output of the idle cylinders 33 and 36 increases as indicated by reference numeral K in the same figure, and the output of the second motor 13 is reduced correspondingly as indicated by reference numeral L in the same figure.

  Further, at the time t3, when the ECU 19 is included in the region where the SOC is low, the ECU 19 sets the ignition timing to a time when the amount of shifting the ignition timing to the retard side becomes larger than when the ECU 19 is included in the region where the SOC is high. In this case, the output of the deactivated cylinders 33 and 36 is reduced according to the further retarded amount, as indicated by the symbol M in FIG. On the other hand, since the ignition timing is set to a time when the retard amount is greatly shifted, the high-temperature exhaust gas generated by the post-combustion of the combustion timing of the idle cylinders 33 and 36 is positively sent to the second catalyst 57. The temperature of the second catalyst 57 rises early. For this reason, when the SOC is low during the execution of the E / G retarded angle mode, the timing for raising the temperature of the second catalyst 57 to the activation temperature by the time t4 'to the time t4' can be advanced. Between the time t3 and the time t4 ′, the output of the second motor 13 is increased as indicated by the symbol N in the same figure as the output of the idle cylinders 33 and 36 due to the ignition delay corresponding to the SOC decreases. The Even when the SOC is low during the catalyst warm-up mode described with reference to FIG. 5, the ignition timing is similarly set to a timing shifted greatly to the retard side, so the temperature of the second catalyst 57 is set to the activation temperature. It can be raised early.

  FIG. 7 is an explanatory diagram showing the relationship between the engine torque and the exhaust temperature with respect to the retard amount of the ignition timing. As shown in FIG. 7, the relationship between the rate of decrease in engine torque and the rate of increase in exhaust temperature (warming-up acceleration rate) relative to the amount by which the ignition timing is shifted from the advance side to the retard side (retard amount) is different. It has become. That is, if the retard amount is, for example, “y”, the engine torque has a decrease rate of “x”, while the exhaust temperature has an increase rate of “K” (x <K). That is, when the retard amount is increased, the warm-up acceleration rate becomes larger than the engine torque decrease rate. For this reason, the capacity of the battery 20 that is not consumed by suppressing the output of the second motor 13 by promoting warm-up is the battery that is consumed for outputting the second motor 13 as the engine torque decreases due to the ignition retardation. Since it exceeds the capacity of 20, a battery suppression effect is obtained.

  FIG. 8 is an explanatory diagram showing the relationship between the engine torque and the exhaust temperature with respect to the opening amount of the throttle valve 47. As shown in FIG. 8, when the amount by which the ignition timing is shifted to the retard side is “z”, the engine torque decreases from “O” to “P”. On the other hand, when the opening degree of the throttle valve 47 is increased, the engine torque can be maintained at approximately “O” as indicated by the dotted line Q, even when the ignition delay is being performed. Further, while the exhaust temperature increases from “R” to “S”, when the opening of the throttle valve 47 is increased, the exhaust temperature is further increased from the temperature “S” as indicated by the dotted line T. be able to. Therefore, the ECU 19 may perform control so as to increase the opening of the throttle valve 47 in accordance with the SOC when performing the ignition delay for warming up the catalyst. In this case, a process of “detecting remaining SOC capacity” is added before the process of “calculation of throttle opening during catalyst warm-up mode”, which is the process of step S13 described in FIG. The ECU 19 may perform control so that the opening degree of the throttle valve 47 is increased as the SOC remaining capacity is smaller. According to this, when the opening degree of the throttle valve 47 is increased, the decrease in the engine torque is reduced, so that the output of the second motor 13 can be reduced. Further, since the exhaust temperature further increases by increasing the opening of the throttle valve 47, the catalyst warm-up operation time can be greatly shortened.

  Although the present invention has been described based on the embodiments, the present invention is not limited to the above-described embodiments, and various modifications are made without departing from the spirit of the present invention. For example, the vehicle of the present invention may be a plug-in hybrid vehicle that can be charged by an external power source. Further, the hybrid vehicle has been described as an example in which two motors 12 and 13 are mounted. However, a vehicle in which one or three or more motors are mounted may be used. Further, for example, in the above embodiment, the cylinder arrangement of the internal combustion engine is an example using the in-line type, but the cylinder arrangement of the internal combustion engine of the present invention is not limited to this, and is V-type, W-type, horizontally opposed Molds and stars may be used.

  In each of the embodiments described above, the idle cylinders are determined as the first cylinder 33 and the fourth cylinder 36, but are not limited to these. For example, the second cylinder 34 and the third cylinder 35, or the first cylinder 33 and the second cylinder 34 are used. Alternatively, the third cylinder 35 and the fourth cylinder 36 may be used. Further, the idle cylinder may be one or three cylinders. Furthermore, the engine described in each of the above embodiments may be an engine that outputs a driving force by a hydrocarbon-based fuel such as gasoline or light oil. The engine is described as an in-cylinder direct injection engine that supplies fuel directly into the cylinder separately from air, but fuel is injected at the intake port and an air-fuel mixture is supplied into the cylinder. It may be a port injection type.

  Further, an electric heating unit may be installed on the outer periphery of the second catalyst 57 or the second exhaust pipe 56, and the second catalyst 57 or the second exhaust pipe 56 may be heated from the outer periphery by the electric heating unit. This heating is performed together with the catalyst warm-up mode or the E / G retarded angle mode. According to this, since the 2nd catalyst 57 can be heated up to activation temperature at an early stage, the consumption of the battery 20 can be suppressed.

  DESCRIPTION OF SYMBOLS 11 ... Engine, 12 ... 1st motor, 13 ... 2nd motor, 19 ... ECU, 20 ... Battery, 21 ... Power supply part, 33, 36 ... Pause cylinder, 34, 35 ... Operation cylinder, 53 ... Exhaust gas purification part, 55 ... 1st catalyst, 57 ... 2nd catalyst, 58 ... Exhaust temperature sensor.

Claims (1)

An internal combustion engine having an operating cylinder that is always activated during operation and a deactivated cylinder that is deactivated;
An exhaust gas purification unit having a first catalyst into which exhaust gas from the operating cylinder flows and a second catalyst into which exhaust gas from the idle cylinder flows;
A first detector for detecting an estimated temperature of the second catalyst;
An electric motor having a function of generating electric power by a driving force output from the internal combustion engine;
A battery for storing electric power generated by the electric motor;
Estimated temperature of the second catalyst based on information obtained from the first detection unit when switching from a reduced cylinder operation in which the deactivated cylinder is deactivated to an all cylinder operation in which the deactivated cylinder is activated. In a control device for a hybrid vehicle, comprising: a control unit that performs a first control for retarding the ignition timing of the idle cylinder when the temperature does not reach a predetermined temperature;
A second detector for detecting the remaining capacity of the battery;
The control unit performs a second control for outputting a driving force for traveling from the electric motor using the electric power stored in the battery during the first control, and the first control and the When performing the second control, the smaller the remaining capacity of the battery detected by the second detection unit, the more the amount by which the ignition timing in the combustion stroke of the idle cylinder is shifted to the retard side than the ignition timing of the operating cylinder. A control device for a hybrid vehicle, characterized in that the control device is configured to set the time when the vehicle becomes large.

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