Hybrid vehicle control device

Abstract

To suppress racing of an internal combustion engine during catalyst warming-up.SOLUTION: A controller for hybrid vehicle includes: a traveling motor generator which supplies a drive wheel with a driving force and generates power by regenerative brake; a motor generator for power generation which is driven by an internal combustion engine and generates power; and a power storage device charged / discharged by the traveling motor generator and the motor generator for power generation. The controller for hybrid vehicle is provided for a hybrid vehicle where a power generation amount by the motor generator for power generation is restricted in accordance with a restriction situation of charge performance of the power storage device, and is provided with a catalyst warming-up control part. The catalyst warming-up control part reduces an amount of retardation defined in accordance with water temperature the greater the rotary frequency is on the basis of water temperature of cooling water of the internal combustion engine and the rotation frequency of the internal combustion engine during catalyst warming-up, performs retardation correction control so that the reduced amount of retardation is secured, and performs control to reduce throttle opening the larger a reduction amount of the amount of retardation is.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a control device for a hybrid vehicle. [Background technology]

[0002] Conventionally, hybrid vehicles equipped with two types of power sources, an electric motor and an internal combustion engine, are known. In particular, series-type hybrid vehicles are known to generate electricity using a power generating motor generator directly connected to the internal combustion engine, store the generated electricity in an electricity storage device, and drive a traction motor generator directly connected to the tire axle to run the vehicle. When accelerating, the vehicle is powered by driving the traction motor generator, and when decelerating, the vehicle efficiently runs by storing deceleration energy in the electricity storage device through regeneration by the traction motor generator.

[0003] In vehicles such as hybrid vehicles, catalyst warm-up is performed to warm up a catalyst that purifies exhaust gas. During catalyst warm-up, the output of the internal combustion engine is controlled to be constant regardless of the amount of power generated by the power generating motor generator, from the viewpoint of improving catalyst warm-up performance (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2004-251178 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a hybrid vehicle, the amount of electricity generated by the power generation motor generator may be limited in a situation where the charging performance of the power storage device is limited, such as an ultra-low temperature environment. If the amount of electricity generated by the power generation motor generator is limited during catalyst warm-up, the output of the internal combustion engine may exceed the output of the power generation motor generator, causing the internal combustion engine to rev up, increasing its rotation speed. For this reason, in the conventional technology, the internal combustion engine may rev up during catalyst warm-up.

[0006] The problem to be solved by the present disclosure is to provide a control device for a hybrid vehicle that can suppress the engine speed increasing when the catalyst is warmed up. [Means for solving the problem]

[0007] The control device for a hybrid vehicle according to the present disclosure includes a driving motor generator that supplies driving force to drive wheels and generates electricity by regenerative braking, a power generation motor generator that is driven by an internal combustion engine and generates electricity, and an electricity storage device that is charged and discharged by the driving motor generator and the power generation motor generator, Depending on the temperature environment The catalyst warm-up control unit is provided in a hybrid vehicle in which the amount of power generated by the power generating motor generator is limited in accordance with a limiting condition of the charging performance. In the state where the amount of power generation is limited During catalyst warm-up, the temperature of the cooling water of the internal combustion engine is determined based on the temperature of the cooling water of the internal combustion engine and the rotation speed of the internal combustion engine, and the higher the rotation speed, the higher the temperature of the cooling water is determined. is the amount by which the ignition timing of the spark plug provided in the internal combustion engine is retarded. The amount of retardation is decreased, and retardation correction control is performed so as to achieve the decreased amount of retardation, and control is performed such that the throttle opening is decreased as the amount of decrease in the amount of retardation is greater. Effect of the Invention

[0008] According to the control device for a hybrid vehicle according to the present disclosure, it is possible to suppress the acceleration of the internal combustion engine when the catalyst is warming up. [Brief description of the drawings]

[0009] [Figure 1]FIG. 1 is a diagram showing a schematic configuration of a vehicle. [Diagram 2] FIG. 2 is a hardware configuration diagram of the vehicle control device. [Diagram 3] FIG. 3 is a schematic diagram showing the configuration of an internal combustion engine. [Figure 4] FIG. 4 is a flowchart showing the flow of information processing executed by the catalyst warm-up control unit. [Diagram 5] FIG. 5 is a flowchart showing the flow of information processing executed by the HEV_ECU during catalyst warm-up. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a control device for a hybrid vehicle according to the present disclosure will be described with reference to the accompanying drawings.

[0011] 1 is a diagram showing a schematic configuration of a vehicle 1 according to the present embodiment. The vehicle 1 is an example of a hybrid vehicle. In the present embodiment, the vehicle 1 is described as a series hybrid vehicle by way of example.

[0012] The vehicle 1 includes a vehicle control device 10, an internal combustion engine 12, a power generating motor generator 14, a traveling motor generator 16, and an electricity storage device 18.

[0013] The internal combustion engine 12 is, for example, a four-stroke engine including a plurality of cylinders.

[0014] The power generation motor generator 14 is driven by the internal combustion engine 12 to generate electricity. A crankshaft, which is a rotating shaft of the internal combustion engine 12, is mechanically connected to a rotating shaft of the power generation motor generator 14 via a gear mechanism. The rotational driving force output by the internal combustion engine 12 is input to the power generation motor generator 14, causing the power generation motor generator 14 to generate electricity. The electricity generated by the power generation motor generator 14 is charged into the power storage device 18 and supplied to the traveling motor generator 16.

[0015] The power generating motor generator 14 also functions as an electric motor that generates a rotational driving force to rotate the crankshaft of the internal combustion engine 12. For example, the power generating motor generator 14 executes cranking to start the internal combustion engine 12 that is stopped.

[0016] The traveling motor generator 16 supplies driving force to the driving wheels 22 and generates electricity through regenerative braking. In detail, the traveling motor generator 16 generates driving force for traveling the vehicle 1 using electric power supplied from the power generation motor generator 14 and the power storage device 18, and outputs the driving force to the driving wheels 22 via a reduction gear 61. The traveling motor generator 16 also generates electricity by rotating in conjunction with the driving wheels 22, and recovers the kinetic energy of the vehicle 1 as electrical energy. The electric power generated through this regenerative braking is charged to the power storage device 18.

[0017] There are cases where power is stored up to the capacity of the power storage device 18, and further charging is difficult. In this case, power generated by regenerative braking of the traveling motor generator 16 is supplied to the power generation motor generator 14, and the power generation motor generator 14 is driven as an electric motor to rotate the internal combustion engine 12, thereby consuming surplus power. By consuming the surplus power, the braking performance of the vehicle 1 is maintained while the surplus power is consumed.

[0018] The power storage device 18 is charged and discharged by the power generation motor generator 14 and the travel motor generator 16. The power storage device 18 is charged with and stores electric power generated by each of the power generation motor generator 14 and the travel motor generator 16. The power storage device 18 also discharges electric power for operating each of the power generation motor generator 14 and the travel motor generator 16 as electric motors, and supplies the electric power required by each of the power generation motor generator 14 and the travel motor generator 16. The power storage device 18 is, for example, a battery or a capacitor.

[0019] The inverter 24 and the inverter 26 function as part of a PCU (Power Control Unit).

[0020] The inverter 24 converts the AC power generated by the power generation motor generator 14 into DC power and outputs it to at least one of the power storage device 18 and the inverter 26. When the power generation motor generator 14 is operated as an electric motor, the inverter 24 converts the DC power supplied from at least one of the power storage device 18 and the inverter 26 into AC power and outputs it to the power generation motor generator 14.

[0021] The inverter 26 converts DC power supplied from at least one of the power storage device 18 and the inverter 24 into AC power and outputs it to the traveling motor generator 16. The inverter 26 also converts AC power generated by the traveling motor generator 16 due to regenerative braking into DC power and outputs it to at least one of the power storage device 18 and the inverter 24.

[0022] The vehicle control device 10 is a controller that controls the vehicle 1. The vehicle control device 10 is an example of a control device for a hybrid vehicle.

[0023] The vehicle control device 10 acquires detection results from various sensors mounted on the vehicle 1. For example, the vehicle control device 10 acquires the vehicle speed of the vehicle 1, the ambient temperature of the power storage device 18, the charging / discharging current for the power storage device 18, the remaining capacity of the power storage device 18, the accelerator opening, the shift position, the ON / OFF state of a switch, the gradient of the road surface, the generated power of the power generation motor generator 14, the generated power of the traveling motor generator 16, and the like. In response to these detection results, the vehicle control device 10 controls the rotational driving force of the traveling motor generator 16, the rotational driving force of the internal combustion engine 12, the magnitude of the power generated by the power generation motor generator 14, and the like.

[0024] The vehicle control device 10 includes, for example, an HEV_ECU (Electronic Control Unit) 30, an engine ECU 32, a generator ECU , a battery ECU , and a drive machine ECU .

[0025] The HEV_ECU 30, the engine ECU 32, the generator ECU 34, the battery ECU 36, and the drive machine ECU 38 are connected to each other so as to be able to communicate with each other via an electric communication line such as a CAN (Controller Area Network).

[0026] The HEV_ECU 30 manages and controls the engine ECU 32, the generator ECU 34, the battery ECU 36, and the drive unit ECU 38, etc. The HEV_ECU 30 optimally distributes the output of the internal combustion engine 12, the power generation motor generator 14, and the driving motor generator 16, etc., according to the vehicle load, driving conditions, etc., and controls the entire hybrid system of the vehicle 1 so that the vehicle 1 can run most efficiently.

[0027] The engine ECU 32 is an engine controller that controls the internal combustion engine 12. The engine ECU 32 includes a catalyst warm-up control unit 32A. The catalyst warm-up control unit 32A will be described in detail later. The generator ECU 34 is a controller that controls the power generation motor generator 14 and the inverter 24. The battery ECU 36 is a controller that controls the power storage device 18. The drive machine ECU 38 is a controller that controls the travel motor generator 16 and the inverter 26.

[0028] FIG. 2 is a diagram illustrating an example of a hardware configuration of the vehicle control device 10. As shown in FIG.

[0029] The HEV_ECU 30, engine ECU 32, generator ECU 34, battery ECU 36, and drive machine ECU 38 provided in the vehicle control device 10 are a hardware configuration utilizing a normal computer, in which a CPU (Central Processing Unit) 11A, a ROM (Read Only Memory) 11B, a RAM (Random Access Memory) 11C, an I / F 11D, etc. are interconnected via a bus 11E.

[0030] The CPU 11A is a calculation device that controls the vehicle control device 10 of this embodiment. The ROM 11B stores programs and the like that realize various processes by the CPU 11A. The RAM 11C stores data necessary for various processes by the CPU 11A. The I / F 11D is an interface for transmitting and receiving data.

[0031] The program for executing information processing executed by the vehicle control device 10 of this embodiment is provided by being pre-installed in the ROM 11B, etc. The program executed by the vehicle control device 10 of this embodiment may be provided by being recorded in a computer-readable recording medium such as a CD-ROM, a flexible disk (FD), a CD-R, or a digital versatile disk (DVD) in a format that can be installed in the vehicle control device 10 or in a format that can be executed.

[0032] FIG. 3 is a schematic diagram showing an example of the internal combustion engine 12. As shown in FIG.

[0033] The internal combustion engine 12 is configured as an engine capable of outputting power using a hydrocarbon fuel such as gasoline or diesel.

[0034] The internal combustion engine 12 has a cylinder 41. An injector 42 that injects fuel is provided near the intake port of the cylinder 41. An ignition plug 43 is attached to the ceiling of the combustion chamber of the cylinder 41. The ignition plug 43 generates a spark discharge between a center electrode and a ground electrode when an induced voltage generated in an ignition coil is applied to the ignition plug 43. The ignition coil is integrally built into a coil case together with an igniter, which is a semiconductor switching element.

[0035] An intake passage 44 for supplying intake air takes in air from the outside and guides it to the intake port of the cylinder 41. An air cleaner 45, an electronic throttle valve 46, a surge tank 47, and an intake manifold 48 are arranged in this order from the upstream side to the downstream side of the intake air on the intake passage 44. An exhaust passage 49 for discharging exhaust gas guides exhaust gas generated by fuel combustion inside the cylinder 41 from the exhaust port of the cylinder 41 to the outside. An exhaust manifold 50 and a three-way catalyst 51 for purifying exhaust gas are arranged on the exhaust passage 49.

[0036] The three-way catalyst 51 is a catalyst that purifies the exhaust gas from the internal combustion engine 12. The three-way catalyst 51 is a well-known catalyst that is activated at a predetermined temperature or higher and simultaneously oxidizes hydrocarbons and carbon monoxide and reduces nitrogen oxides, and is installed in internal combustion engines for vehicles.

[0037] The internal combustion engine 12 takes in air that has been purified by an air cleaner 45 through an electronic throttle valve 46. The internal combustion engine 12 injects fuel from an injector 42 and mixes it with the air that has been taken in, and takes the resulting mixture into the cylinders 41, which are fuel chambers, through an intake manifold 48. The mixture taken into the cylinders 41 explodes and burns due to an electric spark from an ignition plug 43, and the resulting energy pushes down the pistons, and the reciprocating motion of the pistons is converted into the rotational motion of a crankshaft to drive the internal combustion engine 12. Exhaust from the internal combustion engine 12 is discharged to the outside air through an exhaust passage 49 and a three-way catalyst 51.

[0038] The internal combustion engine 12 is driven under the control of the engine ECU 32 .

[0039] The engine ECU 32 receives signals representing the detection results of various sensors provided in the vehicle 1 and the internal combustion engine 12. For example, the engine ECU 32 receives a water temperature signal representing a water temperature detected by a water temperature sensor that detects the coolant temperature of the internal combustion engine 12, and a rotation speed signal representing the rotation speed detected by an engine rotation speed sensor that detects the rotation speed of the internal combustion engine 12. The rotation speed of the internal combustion engine 12 may be referred to as engine rotation speed. In addition, the engine ECU 32 receives various signals, such as a vehicle speed signal representing the actual vehicle speed of the vehicle 1, an accelerator opening signal representing an accelerator opening, an intake temperature / intake pressure signal representing the intake temperature and intake pressure in the intake passage 44, and a cam angle signal representing multiple cam angles of the intake camshaft or exhaust camshaft.

[0040] The engine ECU 32 controls the operation of the internal combustion engine 12 in response to the input signals. For example, the engine ECU 32 determines various operating parameters such as an estimated intake amount, a fuel injection amount, a fuel injection timing, a fuel injection pressure, an ignition timing, and a required EGR (Exhaust Gas Recirculation) amount in response to the input signals. Known methods can be used to determine the operating parameters. The engine ECU 32 outputs various control signals corresponding to the operating parameters to each mechanism of the internal combustion engine 12. For example, the engine ECU 32 outputs an ignition signal to an igniter of the spark plug 43, a fuel injection signal to the injector 42, an opening degree operation signal to the electronic throttle valve 46, and the like.

[0041] The engine ECU 32 includes a catalyst warm-up control unit 32A.

[0042] The catalyst warm-up control unit 32A performs retardation correction control for catalyst warm-up. The retardation correction control for catalyst warm-up is a control for retarding the ignition timing of the spark plug 43 in order to warm up the three-way catalyst 51, which is a catalyst, and raise the temperature of the catalyst to an activation temperature to activate the three-way catalyst 51. Retarding the ignition timing increases the exhaust temperature, making it possible to promote catalyst warm-up of the three-way catalyst 51. The catalyst warm-up control unit 32A performs retardation correction control for catalyst warm-up when it is estimated that the temperature of the three-way catalyst 51 is below the activation temperature, such as when the internal combustion engine 12 is started.

[0043] During catalyst warm-up, the engine ECU 32 controls the internal combustion engine 12 so that the output is constant regardless of the amount of power generated by the power generation motor generator 14, from the viewpoint of improving catalyst warm-up performance.

[0044] Furthermore, in a situation where the charging performance of the power storage device 18 is limited, such as an ultra-low temperature environment, the HEV_ECU 30 controls the power generation motor generator 14 to limit the amount of power generation in order to suppress deterioration of the power storage device 18.

[0045] However, if the amount of electricity generated by the generator motor-generator 14 is limited during catalyst warm-up, the output of the internal combustion engine 12, which is controlled to a constant output, may exceed the output of the generator motor-generator 14, causing the internal combustion engine 12 to rev up and increase in rotation speed.

[0046] Therefore, the catalyst warm-up control unit 32A of this embodiment performs control during catalyst warm-up to reduce the throttle opening of the electronic throttle valve 46 as the rotation speed of the internal combustion engine 12 increases. By the catalyst warm-up control unit 32A performing control to reduce the throttle opening in accordance with the rotation speed of the internal combustion engine 12 during catalyst warm-up, the amount of air flowing into the internal combustion engine 12 is reduced, and it is possible to suppress the internal combustion engine 12 from racing during catalyst warm-up.

[0047] Although reducing the throttle opening of the electronic throttle valve 46 suppresses the engine from revving up, it may not be possible to achieve a balance between the retardation of the ignition timing and the amount of air inflow, resulting in a loss of combustion stability in the internal combustion engine 12. If the internal combustion engine 12 is unable to achieve combustion stability, it may cause misfires in the internal combustion engine 12 or a deterioration in exhaust emissions due to an increase in the amount of unburned components in the exhaust.

[0048] Therefore, the catalyst warm-up control unit 32A of this embodiment performs retard angle correction control based on the water temperature of the cooling water of the internal combustion engine 12 and the rotation speed of the internal combustion engine 12, so that the retard angle amount determined in accordance with the water temperature is reduced as the rotation speed increases, thereby achieving the reduced retard angle amount.

[0049] The catalyst warm-up control unit 32A uses the rotation speed of the internal combustion engine 12 in addition to the water temperature of the cooling water, and reduces the amount of retardation determined according to the water temperature as the rotation speed increases, thereby making it possible to suppress a decrease in the combustion stability of the internal combustion engine 12 and suppress misfires and deterioration of exhaust emissions.

[0050] The control performed by the catalyst warm-up control section 32A will be described in detail below.

[0051] The catalyst warm-up control unit 32A executes the following control during catalyst warm-up.

[0052] The catalyst warm-up control unit 32A acquires the temperature of the cooling water for the internal combustion engine 12, which is represented by a water temperature signal detected by a water temperature sensor, and the rotation speed of the internal combustion engine 12, which is detected by an engine rotation speed sensor.

[0053] The catalyst warm-up control unit 32A determines the amount of retardation according to the acquired water temperature. A known method may be used to determine the amount of retardation according to the water temperature. For example, the catalyst warm-up control unit 32A determines a larger amount of retardation as the acquired water temperature becomes lower.

[0054] Then, the catalyst warm-up control unit 32A further reduces the retard amount determined in accordance with the water temperature as the acquired rotation speed becomes higher. That is, the catalyst warm-up control unit 32A reduces the retard amount determined in accordance with the water temperature so that the amount by which the ignition timing of the ignition plug 43 is retarded becomes smaller as the rotation speed, which is the engine rotation speed, becomes higher.

[0055] The catalyst warm-up control unit 32A reduces the retard amount determined according to the water temperature as the engine speed increases, thereby decreasing the retard amount from the optimal ignition timing for stable combustion. Therefore, the catalyst warm-up control unit 32A can determine a retard amount that can suppress a decrease in the combustion stability of the internal combustion engine 12 and suppress misfires and deterioration of exhaust emissions.

[0056] In addition, the catalyst warm-up control unit 32A determines the throttle opening degree using the retard amount determined according to the water temperature and the engine speed.

[0057] In detail, the catalyst warm-up control unit 32A determines a throttle opening that is reduced so that the amount of air inflow is reduced as the amount of reduction in the retardation amount after reduction using the rotation speed relative to the retardation amount determined according to the water temperature is greater. As described above, the catalyst warm-up control unit 32A reduces the retardation amount determined according to the water temperature as the rotation speed is higher. Therefore, the catalyst warm-up control unit 32A determines a throttle opening that is reduced as the engine rotation speed of the internal combustion engine 12 is higher by determining a throttle opening that is in accordance with the amount of reduction in the retardation amount after reduction using the rotation speed relative to the retardation amount before reduction using the rotation speed.

[0058] The catalyst warm-up control unit 32A may determine a throttle opening that is more decreased as the retard amount determined according to the water temperature and the engine speed is smaller, so that the higher the engine speed is, the more decreased the throttle opening is determined. In this case, for example, the catalyst warm-up control unit 32A stores in advance a table that indicates the relationship between the retard amount determined according to the water temperature and the engine speed and the throttle opening that satisfies the above condition. The catalyst warm-up control unit 32A may then determine the throttle opening by identifying the throttle opening that corresponds to the retard amount determined according to the water temperature and the engine speed in the table.

[0059] During catalyst warm-up, the catalyst warm-up control unit 32A performs retard correction control using a retard amount determined according to the water temperature and engine speed, and controls the throttle opening of the electronic throttle valve 46 to the determined throttle opening.

[0060] In detail, for example, catalyst warm-up control unit 32A retards the ignition timing of spark plug 43 by a predetermined amount every cycle (e.g., 0.16 ms) until the retard amount of the ignition timing reaches the retard amount determined according to the water temperature and the rotation speed. Then, when the retard amount of the ignition timing reaches the retard amount determined according to the water temperature and the rotation speed, catalyst warm-up control unit 32A maintains the retard amount of the ignition timing at the retard amount determined according to the water temperature and the rotation speed. Through these controls, catalyst warm-up control unit 32A performs retard correction control using the retard amount determined according to the water temperature and the rotation speed.

[0061] In addition to the retard correction control, the catalyst warm-up control section 32A also performs throttle opening control to control the throttle opening of the electronic throttle valve 46 to the determined throttle opening.

[0062] The catalyst warm-up control unit 32A continues to determine the amount of retard depending on the water temperature and engine speed, determine the throttle opening, perform the retard correction control, and control the throttle opening, until it determines that the catalyst warm-up end condition is satisfied.

[0063] Therefore, the catalyst warm-up control unit 32A can suppress the revving up of the internal combustion engine 12 during catalyst warm-up. In addition, the catalyst warm-up control unit 32A can suppress the deterioration of the combustion stability of the internal combustion engine 12 during catalyst warm-up, and can suppress misfires and deterioration of exhaust emissions.

[0064] Next, an example of the flow of information processing executed by the catalyst warm-up control unit 32A of the engine ECU 32 of this embodiment will be described.

[0065] FIG. 4 is a flowchart showing an example of the flow of information processing executed by the catalyst warm-up control unit 32A of this embodiment.

[0066] The catalyst warm-up control unit 32A determines whether or not a condition for executing catalyst warm-up is satisfied (step S100). For example, the catalyst warm-up control unit 32A makes the determination in step S100 by determining whether or not a predetermined condition for executing catalyst warm-up is satisfied, such as whether the internal combustion engine 12 has just finished starting, whether the temperature of the three-way catalyst 51 is lower than the activation temperature, etc. If a negative determination is made in step S100 (step S100: No), this routine ends. If a positive determination is made in step S100 (step S100: Yes), the routine proceeds to step S102.

[0067] The catalyst warm-up control unit 32A transmits a catalyst warm-up request signal to the HEV_ECU 30 (step S102). If the signal received from the HEV_ECU 30 in response to the catalyst warm-up request signal is a signal indicating permission for catalyst warm-up (step S104: Yes), the catalyst warm-up control unit 32A proceeds to step S106. If the signal received from the HEV_ECU 30 is a signal indicating non-permission for catalyst warm-up (step S104: No), the catalyst warm-up control unit 32A ends this routine.

[0068] The catalyst warm-up control unit 32A determines the amount of retardation using the water temperature represented by the water temperature signal of the internal combustion engine 12 detected by the water temperature sensor and the rotation speed of the internal combustion engine 12 detected by the engine rotation speed sensor (step S106). The catalyst warm-up control unit 32A determines the amount of retardation according to the water temperature, and determines the amount of retardation by decreasing the amount of retardation determined according to the water temperature as the rotation speed increases.

[0069] The catalyst warm-up control unit 32A determines the throttle opening degree using the retard amount determined in step S106 (step S108). The catalyst warm-up control unit 32A determines the throttle opening degree to be reduced more as the retard amount after reduction using the rotation speed for the retard amount determined according to the water temperature is reduced by a larger amount. That is, the catalyst warm-up control unit 32A determines the throttle opening degree to be reduced more as the engine speed of the internal combustion engine 12 is higher.

[0070] The catalyst warm-up control section 32A performs retard correction control using the retard amount determined in step S106, and controls the throttle opening of the electronic throttle valve 46 to the throttle opening determined in step S108 (step S110).

[0071] The catalyst warm-up control unit 32A determines whether or not to end catalyst warm-up (step S112). The catalyst warm-up control unit 32A makes the determination in step S112 by judging whether or not the catalyst warm-up end condition is satisfied. For example, the catalyst warm-up control unit 32A determines that the catalyst warm-up end condition is satisfied when it is detected that the three-way catalyst 51 has risen to an activation temperature or when the shift position of the vehicle 1 has changed from the non-driving range to the driving range. If a negative determination is made in step S112 (step S112: No), the process returns to step S106. If a positive determination is made in step S112 (step S112: Yes), this routine ends.

[0072] Next, an example of the flow of information processing executed by the HEV_ECU 30 of this embodiment will be shown.

[0073] FIG. 5 is a flowchart showing an example of the flow of information processing executed by the HEV_ECU 30 during catalyst warm-up.

[0074] The HEV_ECU 30 determines whether or not a catalyst warm-up request signal has been received from the engine ECU 32 (step S200). If the determination in step S200 is negative (step S200: No), the routine ends. If the determination in step S200 is positive (step S200: Yes), the routine proceeds to step S202.

[0075] In step S202, the HEV_ECU 30 judges whether or not the permission condition for catalyst warm-up is satisfied (step S202). For example, the HEV_ECU 30 has a predetermined priority order for signals received from the engine ECU 32, the generator ECU 34, the battery ECU 36, and the drive unit ECU 38 for each driving mode that indicates the driving state of the vehicle 1. The HEV_ECU 30 judges that the permission condition for catalyst warm-up is satisfied when the priority order of the signal corresponding to the current driving state of the vehicle 1 indicates that the signal received from the engine ECU 32 has a higher priority order than the signals received from the other ECUs (the generator ECU 34, the battery ECU 36, and the drive unit ECU 38). When the HEV_ECU 30 judges that the permission condition is satisfied (step S202: Yes), it transmits a signal indicating permission for catalyst warm-up to the engine ECU 32 (step S204) and ends this routine. When it is determined that the permission condition is not satisfied (step S202: No), the HEV_ECU 30 transmits a signal indicating that catalyst warm-up is not permitted to the engine ECU 32 (step S206), and ends this routine.

[0076] As described above, the vehicle control device 10 (control device for a hybrid vehicle) of this embodiment is provided in a vehicle 1 (hybrid vehicle) that includes a traveling motor generator 16 that supplies driving force to the drive wheels 22 and generates electricity by regenerative braking, a power generation motor generator 14 that is driven by an internal combustion engine 12 to generate electricity, and an electricity storage device 18 that is charged and discharged by the traveling motor generator 16 and the power generation motor generator 14, and that limits the amount of electricity generated by the power generation motor generator 14 depending on the limited state of the charging performance of the electricity storage device 18. The vehicle control device 10 includes a catalyst warm-up control unit 32A. During catalyst warm-up, the catalyst warm-up control unit 32A performs a retard correction control such that the greater the rotation speed, the greater the retard amount determined according to the water temperature, based on the water temperature of the cooling water for the internal combustion engine 12 and the rotation speed of the internal combustion engine 12, and the greater the retard amount, the greater the reduction in the retard amount, and the greater the reduction in the throttle opening.

[0077] When the catalyst is warming up, the catalyst warm-up control unit 32A controls the throttle opening to be reduced as the rotation speed of the internal combustion engine 12 is higher, and as the amount of retardation is reduced, the throttle opening is reduced. This reduces the amount of air flowing into the internal combustion engine 12 when the catalyst is warming up, and suppresses the internal combustion engine 12 from racing when the catalyst is warming up.

[0078] For example, during catalyst warm-up, from the viewpoint of improving catalyst warm-up performance, the engine ECU 32 controls the output of the internal combustion engine 12 to be constant regardless of the amount of power generated by the power generation motor generator 14. In addition, in a situation where the charging performance of the power storage device 18 is limited, such as in an ultra-low temperature environment, the HEV_ECU 30 controls to limit the amount of power generated by the power generation motor generator 14 from the viewpoint of suppressing deterioration of the power storage device 18.

[0079] Here, in the conventional technology, the amount of retardation during catalyst warm-up was determined only from the water temperature of the internal combustion engine 12, and the throttle opening was determined according to the determined water temperature. However, in the conventional technology, if the catalyst warm-up was performed in a state in which the amount of power generated by the electricity generating motor-generator 14 was limited, the output of the internal combustion engine 12 during catalyst warm-up became constant, and the output of the internal combustion engine 12 exceeded the output of the electricity generating motor-generator 14, causing the rotation speed of the internal combustion engine 12 to increase.

[0080] On the other hand, in this embodiment, the catalyst warm-up control unit 32A of the vehicle control device 10 performs control during catalyst warm-up to reduce the rotation speed of the internal combustion engine 12 as it increases, and to reduce the throttle opening as the amount of decrease in the retard amount increases.

[0081] Therefore, the catalyst warm-up control unit 32A of the vehicle control device 10 of this embodiment can prevent the output of the internal combustion engine 12 from exceeding the output of the power generator motor generator 14, even when the amount of power generated by the power generator motor generator 14 is limited during catalyst warm-up, and can suppress the internal combustion engine 12 from revving up.

[0082] Therefore, the vehicle control device 10 of this embodiment can suppress the acceleration of the internal combustion engine 12 when the catalyst is warmed up.

[0083] In addition, the vehicle control device 10 of this embodiment can suppress the acceleration of the internal combustion engine 12 during catalyst warm-up while continuing catalyst warm-up, compared to when catalyst warm-up is simply interrupted in order to suppress the acceleration of the internal combustion engine 12.

[0084] Furthermore, the vehicle control device 10 of this embodiment can suppress a decrease in the rotation speed of the internal combustion engine 12 compared to a control that suppresses the output of the internal combustion engine 12 according to the output of the power generating motor generator 14 during catalyst warm-up. Therefore, the vehicle control device 10 of this embodiment can suppress a state in which the rotation speed of the internal combustion engine 12 decreases during catalyst warm-up, causing a fluctuation in the heat given to the three-way catalyst 51 and making it impossible to sufficiently activate the three-way catalyst 51.

[0085] In addition, the catalyst warm-up control unit 32A of this embodiment performs retard angle correction control based on the water temperature of the cooling water of the internal combustion engine 12 and the rotation speed of the internal combustion engine 12, thereby reducing the retard angle amount determined in accordance with the water temperature as the rotation speed increases, so as to achieve the reduced retard angle amount.

[0086] Therefore, in addition to the above-mentioned effects, the vehicle control device 10 of the present embodiment can suppress a decrease in the combustion stability of the internal combustion engine 12 during catalyst warm-up, and can suppress misfires and deterioration of exhaust emissions.

[0087] Furthermore, in the vehicle control device 10 of this embodiment, the catalyst warm-up control unit 32A performs the above processing according to the water temperature of the internal combustion engine 12 and the rotation speed of the internal combustion engine 12, so the above effects can be obtained by changing the control method without changing the system configuration of the vehicle 1 and the vehicle control device 10. Therefore, in addition to the above effects, the vehicle control device 10 of this embodiment can suppress the revving of the internal combustion engine 12 during catalyst warm-up, misfires in the internal combustion engine 12, and deterioration of exhaust emissions without increasing costs and mass.

[0088] The programs for executing the above-mentioned processes executed by the vehicle control device 10 of the present embodiment may be stored in the HDD. Also, the programs for executing the above-mentioned processes executed by the vehicle control device 10 of the present embodiment may be provided by being pre-installed in the ROM 11B.

[0089] The program for executing the above-mentioned processes executed by the vehicle control device 10 of the above-mentioned embodiment may be stored in a computer-readable storage medium such as a CD-ROM, CD-R, memory card, DVD (Digital Versatile Disc), or flexible disk (FD) in an installable or executable format file and provided as a computer program product. The program for executing the above-mentioned processes executed by the vehicle control device 10 of the present embodiment may be stored on a computer connected to a network such as the Internet and provided by downloading the program via the network. The program for executing the above-mentioned processes executed by the vehicle control device 10 of the present embodiment may be provided or distributed via a network such as the Internet.

[0090] Although the embodiment of the present invention has been described above, the embodiment is presented as an example and is not intended to limit the scope of the invention. This new embodiment can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. This embodiment and its modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0091] 1 vehicle 10 Vehicle control device 32A Catalyst warm-up control unit

Claims

1. The hybrid vehicle is provided with a driving motor generator that supplies driving force to driving wheels and generates electricity by regenerative braking, a power generation motor generator that is driven by an internal combustion engine and generates electricity, and an electricity storage device that is charged and discharged by the driving motor generator and the power generation motor generator, and the amount of electricity generated by the power generation motor generator is limited in accordance with a limiting condition of charging performance according to a temperature environment of the electricity storage device, a catalyst warm-up control unit that, during catalyst warm-up in a state in which the amount of power generation is limited, reduces a delay amount, which is an amount by which an ignition timing of an ignition plug provided in the internal combustion engine is retarded, based on a water temperature of a cooling water of the internal combustion engine and a rotation speed of the internal combustion engine, the greater the rotation speed of the internal combustion engine, and performs a retard correction control to achieve the reduced delay amount, and performs a control to reduce a throttle opening as the reduction amount of the delay amount becomes greater; A control device for a hybrid vehicle comprising:

2. The catalyst warm-up control unit is the retard angle correction control based on the water temperature and the engine speed, and the control of reducing the throttle opening in accordance with the amount of reduction in the retard angle amount are continuously performed from when it is determined that an execution condition for catalyst warm-up is satisfied until when it is determined that an end condition for catalyst warm-up is satisfied. The control device for a hybrid vehicle according to claim 1.

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