Hybrid vehicle control device

Abstract

To provide a hybrid vehicle control device suppressing excessive engine request power from being requested, and suppressing emission deterioration.SOLUTION: A hybrid vehicle control device is installed on a hybrid vehicle provided with an engine, a motor generating electricity using power from the engine and a battery exchanging power with the motor, adds charge request power to vehicle request power based on an accelerator opening at the time of charge request to set an engine request power, and limits the charge request power at the time of sudden acceleration determination of the hybrid vehicle.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a technology for a hybrid vehicle in which a charging / discharging required power is set within an upper limit power range so that the amount of stored electricity becomes a target amount of stored electricity, and the engine and two motors are controlled so that the sum of the set charging / discharging required power and the driving required power is output from the engine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-201245 Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology disclosed in Patent Document 1, the engine power requirement is increased when charging is required, but in situations where the vehicle power requirement increases, such as when accelerating the vehicle, the engine power requirement becomes even greater, leading to worsening of emissions.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a control device for a hybrid vehicle that can suppress the demand for excessive engine power and thereby suppress deterioration of emissions. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, the control device for a hybrid vehicle according to the present invention is provided in a hybrid vehicle having an engine, a motor that generates electricity using power from the engine, and a battery that exchanges power with the motor, and when charging is required, the control device for a hybrid vehicle adds a charging required power to a vehicle required power based on an accelerator opening degree to set an engine required power, and is characterized in that when a sudden acceleration of the hybrid vehicle is determined, the charging required power is limited. [Effects of the Invention]

[0007] The control device for a hybrid vehicle according to the present invention has the effect of suppressing excessive engine power demand, thereby suppressing deterioration of emissions. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a hybrid vehicle according to an embodiment. [Figure 2] FIG. 2 is a diagram showing the limitation of the charging request power when sudden acceleration of the hybrid vehicle is determined. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of a control device for a hybrid vehicle according to the present invention will be described, but the present invention is not limited to the embodiment.

[0010] Fig. 1 is a diagram showing a schematic configuration of a hybrid vehicle 20 according to an embodiment. As shown in Fig. 1, the hybrid vehicle 20 according to the embodiment includes an engine 22, an engine electronic control unit (hereinafter referred to as engine ECU) 24, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a motor electronic control unit (hereinafter referred to as motor ECU) 40, a high-voltage battery 50, a battery electronic control unit (hereinafter referred to as battery ECU) 52, and a hybrid electronic control unit (hereinafter referred to as HVECU) 70.

[0011] The engine 22 outputs power using gasoline, diesel, or the like as fuel. The engine ECU 24 controls the operation of the engine 22. The planetary gear 30 is a single-pinion planetary gear having a carrier connected to a crankshaft 26 of the engine 22 and a ring gear connected to a drive shaft 36 connected to drive wheels 38a and 38b via a differential gear 37. The motor MG1 is configured, for example, as a synchronous generator motor, with its rotor connected to the sun gear of the planetary gear 30. The motor MG2 is configured, for example, as a synchronous generator motor, with its rotor connected to the drive shaft 36. The inverters 41 and 42 drive the motors MG1 and MG2. The motor ECU 40 controls the operation of the motors MG1 and MG2 by controlling the switching of switching elements (not shown) of the inverters 41 and 42. The high-voltage battery 50 is configured, for example, as a lithium-ion secondary battery, and exchanges power with the motors MG1 and MG2 via the inverters 41 and 42. The battery ECU 52 manages the high-voltage battery 50. The HVECU 70 controls the entire vehicle.

[0012] The engine ECU 24 is configured as a microprocessor centered around a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, input / output ports, and communication ports. Signals from various sensors that detect the state of the engine 22 are input to the engine ECU 24 via input ports. The signals input to the engine ECU 24 include a crank position signal from a crank position sensor that detects the rotational position of the crankshaft 26. Another signal input to the engine ECU 24 is a coolant temperature signal from a water temperature sensor that detects the temperature of the coolant for the engine 22. Another signal input to the engine ECU 24 is a throttle position signal from a throttle valve position sensor that detects the position of the throttle valve. Another signal input to the engine ECU 24 is an intake air volume signal from an air flow meter attached to the intake pipe.

[0013] The engine ECU 24 also outputs various control signals for driving the engine 22 via an output port. Examples of signals output from the engine ECU 24 include a drive signal for a fuel injection valve, a drive signal for a throttle motor that adjusts the position of a throttle valve, and a control signal for an ignition coil. The engine ECU 24 communicates with the HVECU 70, controls the operation of the engine 22 based on control signals from the HVECU 70, and outputs data related to the operating state of the engine 22 as necessary. The engine ECU 24 also calculates the rotation speed of the crankshaft 26, i.e., the rotation speed of the engine 22, based on the crank position from a crank position sensor.

[0014] The motor ECU 40 is configured as a microprocessor centered around a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, input / output ports, and communication ports. Signals required for driving and controlling the motors MG1 and MG2 are input to the motor ECU 40 via the input ports. Examples of signals input to the motors MG1 and MG2 include signals indicating the rotational positions of the rotors of the motors MG1 and MG2 from rotational position detection sensors 43 and 44, which detect the rotational positions of the rotors of the motors MG1 and MG2, and signals such as phase currents applied to the motors MG1 and MG2 detected by current sensors.

[0015] In addition, the motor ECU 40 outputs switching control signals and the like to the switching elements of the inverters 41, 42 via an output port. The motor ECU 40 also communicates with the HVECU 70, and controls the drive of the motors MG1, MG2 using control signals from the HVECU 70, and outputs data relating to the operating states of the motors MG1, MG2 to the HVECU 70 as necessary. The motor ECU 40 also calculates the rotational angular velocities and rotation speeds of the motors MG1, MG2 based on the rotational positions of the rotors of the motors MG1, MG2 detected by the rotational position detection sensors 43, 44.

[0016] The battery ECU 52 is configured as a microprocessor centered around a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, input / output ports, communication ports, etc. Signals required for managing the high-voltage battery 50 are input to the battery ECU 52. Examples of signals input to the battery ECU 52 include the inter-terminal voltage Vb from the voltage sensor 51a, the charge / discharge current from the current sensor 51b, and the battery temperature from the temperature sensor 51c.

[0017] The battery ECU 52 also transmits data related to the state of the high-voltage battery 50 to the HVECU 70 via communication as necessary. To manage the high-voltage battery 50, the battery ECU 52 calculates a power storage ratio SOC, which is the ratio of the amount of power that can be discharged from the high-voltage battery 50 at that time to the total capacity, based on an integrated value of the charging / discharging current detected by the current sensor 51b. The battery ECU 52 also calculates an input / output limit, which is the allowable input / output power that can be charged / discharged to / from the high-voltage battery 50, based on the calculated power storage ratio SOC and the battery temperature. The input / output limit of the high-voltage battery 50 can be set by setting a basic value of the input / output limit based on the battery temperature, setting an output limit correction coefficient and an input limit correction coefficient based on the power storage ratio SOC of the high-voltage battery 50, and multiplying the set basic value of the input / output limit by the correction coefficient.

[0018] The HVECU 70 is configured as a microprocessor centered around a CPU 72, and in addition to the CPU 72, includes a ROM 74 that stores processing programs, a RAM 76 that temporarily stores data, input / output ports, and communication ports. Various signals are input to the HVECU 70 via input ports. One signal input to the HVECU 70 is an ignition signal from an ignition switch 80. Another signal input to the HVECU 70 is a shift position signal from a shift position sensor 82 that detects the operating position of a shift lever 81. Another signal input to the HVECU 70 is an accelerator opening signal from an accelerator pedal position sensor 84 that detects the depression amount of an accelerator pedal 83. Another signal input to the HVECU 70 is a brake pedal position signal from a brake pedal position sensor 86 that detects the depression amount of a brake pedal 85. Another signal input to the HVECU 70 is a vehicle speed signal from a vehicle speed sensor 88.

[0019] The HVECU 70 is connected to the engine ECU 24, motor ECU 40, and battery ECU 52 via communication ports to exchange various control signals and data. The shift positions include a parking position, a neutral position, a drive position for forward travel, and a reverse position for reverse travel.

[0020] In hybrid vehicle 20, a user requested torque (vehicle requested torque) to be output to drive shaft 36 is calculated based on the accelerator opening corresponding to the amount of accelerator pedal depression by the driver and the vehicle speed. Then, the operation of engine 22 and motors MG1 and MG2 is controlled so that a user requested power (vehicle requested power) corresponding to this user requested torque (vehicle requested torque) is output to drive shaft 36.

[0021] The operation control of the engine 22 and the motors MG1 and MG2 includes a torque conversion operation mode in which the engine 22 is controlled so that power corresponding to the user's required power (vehicle required power) is output from the engine 22, and the motors MG1 and MG2 are controlled so that all of the power output from the engine 22 is torque converted by the planetary gear 30, the motors MG1 and MG2, and output to the drive shaft 36.

[0022] In addition, the operation control of the engine 22 and the motors MG1 and MG2 includes a charging operation mode in which the engine 22 is controlled to output an engine required power that corresponds to the sum of the user required power (vehicle required power) and the charging required power required to charge the high-voltage battery 50, and the motors MG1 and MG2 are driven and controlled so that all or part of the engine required power output from the engine 22 in conjunction with charging the high-voltage battery 50 is output to the drive shaft 36 as the user required power (vehicle required power) in conjunction with torque conversion by the planetary gear 30, the motors MG1 and MG2.

[0023] In addition, the operation control of the engine 22, motor MG1, and motor MG2 includes a motor operation mode in which the operation of the engine 22 is stopped and the operation is controlled so that motor required power corresponding to the user required power (vehicle required power) from motor MG2 is output to the drive shaft 36.

[0024] In addition, both the torque conversion operation mode and the charge / discharge operation mode are modes that control the engine 22, motor MG1, and motor MG2 so that the user required power (vehicle required power) is output to the drive shaft 36 while operating the engine 22, and since there is no substantial difference in control between them, the two modes are also collectively referred to as engine operation modes.

[0025] In the hybrid driving mode, the charging power requirement of the high-voltage battery 50 is set according to the storage rate SOC of the high-voltage battery 50, and the driving power is added to the set charging power requirement to set the engine power requirement to be output from the engine 22. The engine 22, the motor MG1, and the motor MG2 are controlled so that the engine power requirement is output from the engine 22 and the user-requested torque (vehicle-requested torque) is output to the drive shaft 36, and the vehicle travels by hybrid driving.

[0026] FIG. 2 is a diagram showing the limitation of the charging request power when sudden acceleration of the hybrid vehicle 20 is determined.

[0027] In the hybrid vehicle 20 according to the embodiment, for example, the HVECU 70, which is a control device, sets engine required power by adding a charging required power to a user required power (vehicle required power) based on an accelerator opening when charging of the high-voltage battery 50 is requested (in a charging operation mode). Then, in the hybrid vehicle 20 according to the embodiment, the HVECU 70 limits the charging required power (Pchg amount, which is an amount to be added to the engine required power for charging) when sudden acceleration of the hybrid vehicle 20 is determined, as shown in Fig. 2. At this time, the limit amount of the charging required power (Pchg amount) is calculated by the HVECU 70 based on, for example, the power storage rate SOC of the high-voltage battery 50 and the user required power (vehicle required power).

[0028] The HVECU 70 determines that the hybrid vehicle 20 is experiencing sudden acceleration when, for example, the slope of a graph showing changes in vehicle speed as shown in Fig. 2 is equal to or greater than a first predetermined value. Also, for example, the HVECU 70 determines that the hybrid vehicle 20 is experiencing sudden acceleration when the increase in vehicle speed over a certain period of time is equal to or greater than a second predetermined value.

[0029] In the hybrid vehicle 20 according to the embodiment, the HVECU 70 limits the charging power requirement (Pchg amount) when sudden acceleration of the hybrid vehicle 20 is determined, thereby preventing excessive engine power requirement from being requested of the engine 22 and suppressing deterioration of emissions. [Explanation of symbols]

[0030] 20 Hybrid vehicles 22 Engine 50 High Voltage Battery 70 HVECU MG1, MG2 motors

Claims

[Claim 1] The hybrid vehicle is provided with an engine, a motor that generates electricity using power from the engine, and a battery that exchanges power with the motor, A control device for a hybrid vehicle, wherein when charging is required, a charging required power is added to a vehicle required power based on an accelerator opening degree to set an engine required power, A control device for a hybrid vehicle, wherein the charging request power is limited when it is determined that the hybrid vehicle is rapidly accelerating.

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