Control device for hybrid vehicle

Abstract

The present invention addresses the problem of ensuring required output and improving emissions in a hybrid vehicle. A control device for a hybrid vehicle provided with: a vehicle travel engine connected to an exhaust pipe provided with a catalyst; a control device for a hybrid vehicle, which is driven by electric power of a battery, and a rotating electric machine for vehicle travel, and which switches between an HV travel mode in which the vehicle travels by an engine and the rotating electric machine and an EV travel mode in which the vehicle travels by the rotating electric machine while the engine is stopped, is provided with: a first control unit that generates catalyst warm-up control notification information that notifies the engine and the rotating electric machine; and catalyst warm-up control notification information for executing catalyst warm-up control when the engine is started when it is determined that the catalyst is not warmed up and catalyst warm-up control of the engine is necessary in a state where the EV travel mode is selected.

Description

Technical Field

[0001] This invention relates to a control device for a hybrid vehicle. Background Technology

[0002] Previously, in vehicles equipped with an engine, a first rotary electric motor mechanically connected to the engine's output shaft capable of generating electricity, and a second rotary electric motor for driving, a method for preheating the catalyst for purifying engine exhaust has been proposed (for example, see Patent Document 1). Patent Document 1 discloses rapid catalyst preheating in the idle off state.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2023-163747 Summary of the Invention

[0004] In hybrid vehicles, two driving modes are selected: Hybrid Driving Mode (HV mode) and Electric Driving Mode (EV mode). HV mode powers the vehicle using both the engine and a rotary electric motor. EV mode, on the other hand, powers the vehicle by stopping the engine and relying solely on the rotary electric motor. In EV mode, because the engine is off, catalytic converter preheating is not possible. In situations where high output is required from the hybrid vehicle in EV mode, switching to HV mode may occur. In this case, if catalytic converter preheating is not completed, emissions may sometimes worsen.

[0005] Patent Document 1 proposes catalytic preheating during idle off. Therefore, control related to catalytic preheating begins after the engine is running. Furthermore, Patent Document 1 does not consider the state of the battery driving the rotary motor. As a result, it is argued that to ensure the vehicle's required output, switching from EV driving mode to HV driving mode based on the battery state could easily result in incomplete catalytic preheating. Thus, Patent Document 1 has room for improvement in ensuring the vehicle's required output and emissions.

[0006] Therefore, the subject of the control device for hybrid vehicles disclosed in this specification is to achieve the required output and improve emissions in hybrid vehicles.

[0007] The aforementioned problem can be achieved through a control device for a hybrid vehicle, which includes: an engine connected to an exhaust pipe containing a catalyst, serving as a first drive source for vehicle operation; and a rotary motor driven by battery power, serving as a second drive source for vehicle operation. The control device switches between a hybrid driving mode, where the vehicle operates using both the engine and the rotary motor, and an electric driving mode, where the engine is stopped and the vehicle operates solely using the rotary motor. The control device includes: a first control unit that generates catalyst preheating control warning information. This warning information is used to execute catalyst preheating control when the engine starts, provided that, in the selected electric driving mode, the catalyst is not preheated and catalyst preheating control of the engine is required. The first control unit also switches the driving mode from the electric driving mode to the hybrid driving mode. Before the engine starts, the first control unit notifies a second control unit that executes the engine start command and the catalyst preheating control execution command.

[0008] In the control device of the hybrid vehicle with the above structure, it can be configured such that the control device includes the second control unit, which, when detecting a sign of battery polarization in the battery that supplies power to the rotary motor and receiving the catalyst preheating control warning information, issues the engine start command and the catalyst preheating control execution command to the first control unit.

[0009] Furthermore, in the control device of the hybrid vehicle with the above structure, it can be configured such that the second control unit determines that a sign of battery polarization has been detected when the voltage drop per unit time exceeds a predetermined threshold, based on the relationship between the current duration and voltage in the battery.

[0010] Invention Effects

[0011] The control device for hybrid vehicles disclosed in this specification enables the achievement of required output and improved emissions in hybrid vehicles. Attached Figure Description

[0012] Figure 1 This is a schematic diagram showing the general structure of a hybrid vehicle with a control device for a hybrid vehicle having an implementation method.

[0013] Figure 2 This is a schematic diagram showing the general structure of the engine in the hybrid vehicle described in the embodiment.

[0014] Figure 3This is a flowchart illustrating an example of the control performed by the engine ECU included in the control device of a hybrid vehicle according to an embodiment.

[0015] Figure 4 This is a flowchart illustrating an example of the control performed by the HVECU included in the control device of a hybrid vehicle according to an embodiment.

[0016] Figure 5 This is a graph representing an example of the state of a battery. Detailed Implementation

[0017] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, in the drawings, the dimensions, proportions, etc., of each part are not sometimes illustrated in a manner completely consistent with the actual situation. Furthermore, sometimes detailed descriptions are omitted from the drawings.

[0018] (Implementation Method)

[0019] [Structure of Hybrid Vehicles] First, refer to Figure 1 The hybrid electric vehicle (hereinafter referred to as "vehicle") 100 of the embodiment will be described. Figure 1 This is a schematic diagram illustrating vehicle 100. Vehicle 100 includes an engine 1, a first electric generator (hereinafter referred to as 1MG) 61, a second electric generator (hereinafter referred to as 2MG) 62, a planetary gear mechanism 63, a transmission mechanism 64, and drive wheels 70. Furthermore, vehicle 100 includes a Hybrid Vehicle Electronic Control Unit (HVECU) 30, a Power Control Unit (PCU) 40, an engine ECU (Electronic Control Unit) 50, a battery 80, and a battery ECU 81. Additionally, vehicle 100 includes a vehicle speed sensor 92, a throttle opening sensor 93, a current sensor 94, and a voltage sensor 95. The current sensor 94 is mounted at the output terminal of the battery 80 and measures the current of the battery 80. The voltage sensor 95 is mounted between the terminals of the battery 80 and measures the voltage of the battery 80.

[0020] HVECU30 acts as the second control unit. Engine ECU50 acts as the first control unit. HVECU30 switches between EV driving mode and HV driving mode. Therefore, HVECU30 sends an engine start command to Engine ECU50. Furthermore, HVECU30 executes commands to control the catalyst preheating in engine 1. Engine ECU50 controls the intake air volume or ignition timing accompanying engine 1 operation. Catalyst preheating control is performed by Engine ECU50. HVECU30 and Engine ECU50 exchange information to cooperate in controlling vehicle 100. HVECU30 and Engine ECU50 will be explained in more detail later.

[0021] refer to Figure 2 Engine 1 is the primary drive source for vehicle operation. Engine 1 has multiple cylinders 2 within its cylinder block. Figure 2 Only one cylinder 2 is shown in the diagram. A piston 3 is slidably housed within each cylinder 2. A combustion chamber 2a is formed between the piston 3 and the cylinder head, which is located on the upper side of the cylinder block. The piston 3 is connected to the crankshaft 5 via a connecting rod 4. An injector 6 and a spark plug 7 are provided in the combustion chamber 2a for injecting fuel into the cylinder. The fuel injected from the injector 6 forms a mixture in the combustion chamber 2a and is ignited by the spark plug 7. If the ignited mixture burns and explodes, the piston 3 is pressed down. The pressed piston 3 transmits the explosive force to the crankshaft 5 via the connecting rod 4, causing the crankshaft 5 to rotate. A crankshaft angle sensor 15 for detecting the crankshaft angle is provided in the engine 1. The engine 1 is a gasoline engine, but is not limited to this; it can also be a diesel engine.

[0022] The engine 1 has an air intake 8 and an exhaust port 9 arranged facing the combustion chamber 2a. An intake pipe 10 is connected to the air intake 8. An exhaust pipe 11 is connected to the exhaust port 9.

[0023] On the intake manifold 10, an air filter 12, an air flow meter 13, a throttle valve 17, and an intake manifold 18 are sequentially arranged from the upstream side of the intake air flow. The air flow meter 13 detects the amount of air flowing in the intake manifold 10. The throttle valve 17 adjusts the amount of air supplied to the combustion chamber 2a. The intake manifold 10 is branched by the intake manifold 18 and connected to the intake ports 8 of each cylinder.

[0024] On the exhaust pipe 11, an exhaust manifold 20 and a catalyst 21 are sequentially arranged from the upstream side of the exhaust flow. The catalyst 21 purifies the exhaust.

[0025] Engine 1 has an intake valve 23 for opening and closing the intake port 8 and an exhaust valve 24 for opening and closing the exhaust port 9. The intake valve 23 is opened and closed by a valve mechanism 25. The exhaust valve 24 is opened and closed by a valve mechanism 26.

[0026] The engine ECU 50 includes a central processing unit (CPU), random access memory (RAM), read-only memory (ROM), and storage devices. The engine ECU 50 controls the engine 1 by executing programs stored in the ROM or storage devices. The storage devices store programs or maps for control. The engine ECU 50 functions as a catalyst preheating control unit 50a for preheating the catalyst 21 by executing the program. The catalyst preheating control unit 50a includes a catalyst preheating preparation unit 50a1 and a catalyst preheating execution unit 50a2. Furthermore, a catalyst temperature estimation unit 51 is provided in the catalyst preheating control unit 50a. The catalyst temperature estimation unit 51 estimates the temperature of the catalyst 21 based on information such as the intake air volume. The catalyst preheating control unit 50a is electrically connected to a water temperature sensor 52 that detects the temperature of the coolant circulating in the engine 1. Alternatively, a catalyst temperature sensor may be provided instead of the catalyst temperature estimation unit 51, and the temperature of the catalyst 21 may be detected by the catalyst temperature sensor.

[0027] When the ignition switch is on and the engine 1 is off in EV driving mode, the catalyst preheating preparation unit 50a1 determines whether the catalyst 21 has not been preheated. The determination of whether the catalyst 21 has not been preheated is based on an estimate by the catalyst temperature estimation unit 51. Specifically, if the estimated catalyst temperature is lower than a preset catalyst preheating completion threshold, it is determined that the catalyst 21 has not been preheated. The method for determining whether the catalyst 21 has not been preheated is not limited to this, and various conventionally known methods can be used.

[0028] When the catalyst preheating preparation unit 50a1 determines that catalyst 21 has not been preheated and the catalyst preheating execution conditions are met, it determines that catalyst preheating control is required. In this case, the catalyst preheating preparation unit 50a1 generates catalyst preheating control warning information. The generated catalyst preheating control warning information is transmitted to the HVECU 30 before the engine 1 is started. In this embodiment, when catalyst preheating control warning information is generated, the catalyst preheating control warning flag is set to "on". Therefore, in this embodiment, the HVECU 30 is notified that the catalyst preheating control warning flag is "on" before the engine 1 is started. Thus, when the engine 1 is started, the catalyst preheating preparation unit 50a1 sets the catalyst preheating control to a ready state so as to immediately start catalyst preheating control.

[0029] Here, the catalyst preheating execution conditions are explained. One of the catalyst preheating execution conditions is that the coolant temperature detected by the coolant temperature sensor 52 exceeds a preset lower limit value for catalyst preheating control. This condition is considered to prevent emissions from deteriorating when catalyst preheating control is performed at excessively low coolant temperatures. Furthermore, not being in engine check mode is also included in the catalyst preheating execution conditions. Moreover, the catalyst preheating execution conditions also include the normal functioning of all components in engine 1, for example, no abnormalities detected in on-board diagnostics (OBD). This is because it is assumed that proper catalyst preheating cannot be performed if these conditions are not met. In the following description, these conditions will be collectively referred to as catalyst preheating execution conditions.

[0030] The catalyst preheating actuator 50a2 actually performs catalyst preheating control. In this embodiment, ignition timing delay control is performed. Ignition timing delay control is accompanied by output limitation of engine 1. Furthermore, the content of catalyst preheating control is not limited to ignition timing delay control. Conventionally known catalyst preheating control can be used. For example, the throttle valve 17 can be controlled to adjust the intake air volume, or the fuel injection mode from the injector 6 can be controlled. Moreover, the content of catalyst preheating control can be conventionally known rapid catalyst preheating control, or other controls. When catalyst preheating control is performed, engine output limitation is usually present.

[0031] The engine ECU 50 is electrically connected to the air flow meter 13 and the crankshaft angle sensor 15. The engine ECU 50 calculates the output of the engine 1 based on the detection values ​​of the air flow meter 13 and the crankshaft angle sensor 15.

[0032] MG61 and MG62 are rotary motors, connected to battery 80 via PCU40, HVECU30, and battery ECU81. MG61 and MG62 function as motors that generate driving force for the vehicle based on power supplied from battery 80. Furthermore, MG61 and MG62 also function as generators that produce regenerative power to charge battery 80 based on power transmitted from engine 1 or drive wheels 70. The power supplied between MG61 and MG62 and battery 80 is regulated by PCU40. MG62 serves as a second drive source for vehicle operation. MG61 also functions as a starter motor when starting engine 1.

[0033] PCU40 is a power control device configured to control the input and output of power between the 1st MG61 and the 2nd MG62 and the battery 80. Although not shown, PCU40 includes an inverter, a boost converter, a system main relay (SMR), a motor ECU, etc.

[0034] Planetary gear mechanism 63 mechanically connects the crankshaft 5 of engine 1, the rotating shaft of the first MG61, the rotating shaft of the second MG62, and the output shaft of planetary gear mechanism 63. Planetary gear mechanism 63 includes a rotating sun gear, a ring gear rotating coaxially with the sun gear, a pinion revolving around the sun gear as a center, and a planet carrier rotating coaxially with the sun gear according to the revolution of the pinion. The planet carrier is connected to the crankshaft 5 of engine 1. The sun gear is connected to the rotating shaft of the first MG61. The ring gear is linked to the rotating shaft of the second MG62. Through transmission mechanism 64, the driving force of engine 1 or the first MG61 and second MG62 is transmitted to the drive wheel 70.

[0035] Like the engine ECU 50, the HVECU 30 has a CPU, RAM, ROM, and storage devices. The HVECU 30 controls the entire system of the vehicle 100 by executing programs stored in the ROM or storage devices. The HVECU 30 is electrically connected to the vehicle speed sensor 92, throttle opening sensor 93, current sensor 94, and voltage sensor 95.

[0036] HVECU30 switches the driving mode of vehicle 100 to either EV driving mode or HV driving mode. In EV driving mode, the vehicle travels using the second MG62 as the power source while engine 1 is stopped. In HV driving mode, engine 1 is driven, and the vehicle travels using engine 1 as the power source. Even when at least one of the first MG61 and the second MG62 is used in conjunction with engine 1, this is still considered HV driving mode.

[0037] The driving mode is switched based on the required torque for vehicle 100 calculated from vehicle speed or throttle opening. For example, if the required torque is less than the starting threshold for engine 1 to start, the EV driving mode, in order to improve fuel efficiency, is selected, which disables engine 1. If the required torque is greater than the starting threshold for engine 1 to start, the HV driving mode, in which engine 1 is started, is selected.

[0038] The HVECU 30 includes a battery polarization precursor detection unit (hereinafter referred to as the "prediction unit") 31 and a battery polarization determination unit (hereinafter referred to as the "determination unit") 32. Battery polarization is the deviation between the theoretical electromotive force and the actual operating voltage. It is a phenomenon in which the surface state of charge (SOC) of the active material decreases and the actual electromotive force decreases if current flows continuously to the discharge side for a long time. If battery polarization occurs, a sharp drop in the output of the battery 80 will be observed. When the prediction unit 31 detects a sharp drop in the output of the battery 80, it determines that there is a precursor to battery polarization. When the determination unit 32 detects a predetermined drop in the output of the battery 80, it determines that battery polarization has actually occurred.

[0039] Regarding the signs of battery polarization or the actual determination that battery polarization has occurred, for example, based on... Figure 5 The relationship between battery current duration and voltage is shown to determine polarization. Battery polarization precursor detection and determination will be explained in detail later.

[0040] [Catalyst Preheating Control] Next, refer to Figure 3 and Figure 4 The flowchart shown illustrates an example of control in this embodiment. Figure 3 The flowchart shown is an example of the control performed by the engine ECU 50. Figure 4 The flowchart shown illustrates an example of control performed by the HVECU 30. The control of both is performed in parallel. Furthermore, the HVECU 30 and the engine ECU 50 exchange information; information generated or commands sent by one control are used by the other. Alternatively, in this embodiment, the HVECU 30 and engine ECU 50 are separate, but they could also be integrated into a single control device.

[0041] First, refer to Figure 3 This section explains the control performed by the engine ECU 50. When utilizing information generated by the HVECU 30 or performing actions based on commands sent by the HVECU 30, appropriate reference should be made. Figure 4 .

[0042] In step S1, the catalyst preheating preparation unit 50a1 included in the engine ECU 50 determines whether the ignition switch is turned on. If the determination is affirmative ("yes") in step S1, the process proceeds to step S2. On the other hand, if the determination is negative ("no") in step S1, the process of step S1 is repeated.

[0043] In step S2, the catalyst preheating preparation unit 50a1 determines whether the catalyst 21 is in an unpreheated state. This determination is based on an estimate from the catalyst temperature estimation unit 51. If the estimate from the catalyst temperature estimation unit 51 is lower than a preset threshold, the catalyst 21 is in an unpreheated state. If the determination in step S2 is "yes," the process proceeds to step S3. Conversely, if the determination in step S2 is "no," the engine ECU 50 terminates the process.

[0044] In step S3, the catalyst preheating preparation unit 50a1 determines whether the above-mentioned catalyst preheating execution conditions are met. If the determination in step S3 is "yes", the process proceeds to step S4. On the other hand, if the determination in step S3 is "no", the process of step S2 is repeated.

[0045] In step S4, the catalyst preheating preparation unit 50a1 generates catalyst preheating control warning information and notifies the HVECU 30 of it. In this embodiment, a flag indicating that catalyst preheating control warning information has been generated is set to "on," and the HVECU 30 is notified that the flag is set to "on." After the processing in step S4, the engine ECU 50 proceeds to step S5.

[0046] In step S5, the engine ECU 50 determines whether an engine start command exists. Here, the target of the engine start command is... Figure 4 The flowchart shown includes both the instruction based on step S24 and the instruction based on step S26. That is, if either the engine start instruction based on step S24 or the engine start instruction based on step S26 exists, the condition is determined to be "yes" in step S5. Steps S24 and S26 will be explained later. If the condition is "yes" in step S5, the process proceeds to step S6. On the other hand, if the condition is "no" in step S5, the process of step S5 is repeated.

[0047] In step S6, the engine ECU 50 starts engine 1. After the processing in step S6, the engine ECU 50 proceeds to step S7.

[0048] In step S7, the engine ECU 50 determines whether there is an execution command for catalyst preheating control. Here, the execution command for catalyst preheating control is... Figure 4The flowchart shown is based on the instruction in step S24. That is, in step S6, if engine 1 is started based on the engine start instruction in step S24, the determination is "yes". On the other hand, in step S6, if engine 1 is started based on the engine start instruction in step S26, the determination is "no". If the determination is "yes" in step S7, the process proceeds to step S8. On the other hand, if the determination is "no" in step S7, the engine ECU 50 ends the process.

[0049] In step S8, the catalyst preheating actuator 50a2 included in the engine ECU 50 performs the aforementioned catalyst preheating. In this embodiment, ignition timing delay control is performed. This catalyst preheating improves emissions.

[0050] Next, refer to Figure 4 The control performed by HVECU30 will be explained. When using information generated by engine ECU50, appropriate references will be made. Figure 3 .

[0051] In step S21, the HVECU 30 determines whether the vehicle 100 is in EV driving mode. That is, it determines whether the engine 1 is stopped. If the determination is "yes" in step S21, the process proceeds to step S22. On the other hand, if the determination is "no" in step S21, the HVECU 30 ends the process.

[0052] In step S22, the warning detection unit 31 included in the HVECU 30 determines whether there are signs of battery polarization. Here, refer to... Figure 5 The graph shown illustrates the precursors of battery polarization. Figure 5 The diagram shows the relationship between battery current duration and voltage. Figure 5 In the diagram, the relationship when the current is 50A and the ambient temperature is T1 is represented by a thick solid line. The relationship when the current is 50A and the ambient temperature is T2 is represented by a thick dashed line. Furthermore, the relationship when the current is 100A and the ambient temperature is T1 is represented by a thin solid line. And the relationship when the current is 100A and the ambient temperature is T2 is represented by a thin dashed line. Here, T1 > T2.

[0053] Battery polarization indicators can be determined by whether the rate of voltage drop (ΔV / Δt) exceeds a specified value under continuous discharge conditions. This specified value can be set based on the current value or ambient temperature. For example, based on the current value and ambient temperature... Figure 5As shown, thresholds a1, b1, c1, and d1 can be set. That is, based on the current value and ambient temperature, when threshold a1 is detected, it is determined that there is a sign of battery polarization, and in step S22, it is determined to be "yes". The ambient temperature can be detected by an external temperature sensor or the like (not shown).

[0054] Here, the setting policy for threshold a1, etc., will be explained. Threshold a1, etc., is set such that, assuming a high output is required in vehicle 100 at this stage, the second MG62 can achieve a specified output value. Specifically, it is set so that even when the output of engine 1 is limited by preheating the catalyst, the second MG62 can ensure that the required output of electricity for vehicle 100 is met. If a stage where signs of battery polarization are detected, the battery power can be ensured. Therefore, in this state, if engine 1 is started and catalyst preheating is completed, the required output and improved emissions in vehicle 100 can be achieved. In addition, the current value can be detected by current sensor 94, and the voltage value can be detected by voltage sensor 95.

[0055] If the determination in step S22 is "yes", the process proceeds to step S23. Conversely, if the determination in step S22 is "no", the process proceeds to step S27. In step S27, the EV driving mode continues. After the processing in step S27, the process ends.

[0056] In step S23, the HVECU30 determines whether a catalyst preheating control warning sign exists. That is, the engine ECU50 determines whether to proceed. Figure 3 The process in step S4 of the flowchart shown is as follows: If the result in step S23 is "yes", the process proceeds to step S24. Conversely, if the result in step S23 is "no", the process proceeds to step S25.

[0057] In step S24, HVECU30 executes engine start commands and catalyst preheating control commands to engine ECU50. Therefore, engine ECU50... Figure 3 In step S5 of the flowchart shown, if the determination is "yes", engine 1 is started in step S6. By starting engine 1 in step S6, vehicle 100 switches from EV driving mode to HV driving mode. That is, engine 1 and the second MG62 are used as the drive source for vehicle 100. At this time, although there are signs of battery polarization in battery 80, it is able to supply power to drive the second MG62. Therefore, even if the output of engine 1 is limited, the required output of vehicle 100 can be ensured. After the processing in step S24, the process ends.

[0058] In step S25, the determination unit 32 included in the HVECU 30 determines whether battery polarization has occurred. Here, refer to... Figure 5 A voltage threshold is set. When the voltage is lower than the voltage threshold, the determination unit 32 determines that battery polarization has occurred. If the determination is "yes" in step S25, the process proceeds to step S26. On the other hand, if the determination is "no" in step S25, the process proceeds to step S27. The process of step S27 is the same as the case where the determination is "no" in step S22, so its detailed description is omitted here.

[0059] In step S26, HVECU30 sends an engine start command to engine ECU50. Unlike step S24, the engine start command in step S26 is not accompanied by an execution command for catalyst preheating control. This is because the engine 1 is being started while the battery is in a polarized state. If battery polarization occurs, it is difficult to ensure the output generated by the drive of the second MG62. Therefore, in this case, by operating engine 1 without output limitation, the required output of vehicle 100 is prioritized. After the processing in step S26, the catalyst preheating control in this embodiment ends.

[0060] [Effect]

[0061] According to this embodiment, when the engine 1 is stopped and it is determined that the catalyst 21 is not preheated and catalyst preheating control is required, the catalyst preheating control warning flag, which indicates that catalyst preheating control will be performed when the engine 1 is started, is set to "on" before the engine 1 is started. Therefore, catalyst preheating control can be performed immediately upon starting the engine 1. As a result, emissions can be improved.

[0062] Furthermore, when the catalyst preheating control warning sign is on and signs of battery polarization are detected in the battery 80 supplying power to the 2MG62, the engine 1 is immediately started to perform catalyst preheating control. This ensures the required output of the vehicle 100 while simultaneously improving emissions.

[0063] The above embodiments are merely examples for implementing the present invention, and the present invention is not limited to these. Various modifications to these embodiments are within the scope of the present invention, and other various embodiments are possible within the scope of the present invention, as is evident from the above description.

[0064] Symbol Explanation

[0065] 1-Engine, 2-Cylinder, 3-Piston, 4-Connecting rod, 5-Crankshaft, 6-Injector, 7-Spark plug, 10-Intake manifold, 11-Exhaust manifold, 12-Air filter, 13-Air flow meter, 15-Crankshaft angle sensor, 17-Throttle valve, 21-Catalyst, 30-HVECU, 31-Battery polarization warning detection unit, 32-Battery polarization determination unit, 40-PCU, 50-Engine ECU, 50a-Catalyst preheating control Part, 50a1-Catalyst preheating preparation unit, 50a2-Catalyst preheating execution unit, 51-Catalyst temperature estimation unit, 52-Water temperature sensor, 61-1st MG, 62-2nd MG, 63-Planetary gear mechanism, 64-Transmission mechanism, 70-Drive wheel, 80-Battery, 81-Battery ECU, 92-Vehicle speed sensor, 93-Throttle opening sensor, 94-Current sensor, 95-Voltage sensor, 100-Hybrid vehicle.

Claims

1. A control device for a hybrid vehicle, the hybrid vehicle comprising: an engine connected to an exhaust pipe in which a catalyst is disposed, serving as a first drive source for driving the vehicle; and a rotary motor driven by electricity from a battery, serving as a second drive source for driving the vehicle, and the control device switching driving modes between a hybrid driving mode in which driving is achieved through the engine and the rotary motor, and an electric driving mode in which driving is achieved through the rotary motor when the engine is stopped, the control device being characterized in that it comprises: The first control unit generates catalyst preheating control prediction information. This information is used to determine, when the electric driving mode is selected, that the catalyst is not preheated and requires catalyst preheating control of the engine. In this case, the unit executes the catalyst preheating control when the engine starts. The first control unit, while switching the driving mode from the electric driving mode to the hybrid driving mode, notifies the second control unit, which executes the engine start command and the catalyst preheating control execution command, of the catalyst preheating control advance warning information before the engine starts.

2. The control device for a hybrid vehicle according to claim 1, characterized in that, The control device includes the second control unit. When the second control unit detects a sign of battery polarization occurring in the battery supplying power to the rotating motor and receives the catalyst preheating control warning information, it issues the engine start command and the catalyst preheating control execution command to the first control unit.

3. The control device for a hybrid vehicle according to claim 2, characterized in that, The second control unit determines that a sign of battery polarization has been detected when the voltage drop per unit time exceeds a predetermined threshold, based on the relationship between the current duration and voltage in the battery.

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