JP2016175560A - Hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit generation of relatively large vibration in a vehicle in stopping an engine when a battery is separated from first and second motor sides.SOLUTION: When stopping an engine after finishing battery-less travel, a hybrid vehicle drives and controls a first motor so that torque for lowering an engine revolution speed is output from the first motor (S150, S160). The hybrid vehicle drives and controls a second motor so that electrical power obtained from the first motor without outputting torque from the second motor is consumed by the second motor (S160).SELECTED DRAWING: Figure 2

Description

  The present invention relates to a hybrid vehicle, and more particularly to a hybrid vehicle including an engine, first and second motors, a planetary gear, and a battery.

  Conventionally, in this type of hybrid vehicle, in a hybrid vehicle having a configuration in which an engine, a first motor, and a second motor are connected via a planetary gear, when an abnormality occurs in the battery, the battery is connected to the first and second motor sides. There has been proposed a battery-less traveling that travels separately from the vehicle (see, for example, Patent Document 1). In battery-less travel, the engine and the first motor are controlled so as to output power corresponding to the driver's accelerator operation, and the second motor is controlled so that the electric power generated from the first motor is consumed by the second motor. It is done by doing.

JP 2013-103514 A

  However, in the above-described hybrid vehicle, when the engine is stopped after the battery-less traveling is finished, a relatively large vibration may occur in the vehicle. The engine is stopped by controlling the first motor so as to reduce the engine speed so that the engine speed can quickly pass through the resonance frequency band when there is no abnormality in the battery. At this time, the power generated by the first motor is charged to the battery. In a state where the battery is disconnected from the first and second motor sides, the battery cannot be charged with the electric power generated by the first motor, and thus similar control cannot be performed. For this reason, it is conceivable to stop the fuel injection by stopping the fuel injection to the engine without driving the first motor, but the engine speed cannot pass through the resonance frequency band quickly, and the vehicle A relatively large vibration will occur.

  The main purpose of the hybrid vehicle of the present invention is to suppress the occurrence of relatively large vibrations in the vehicle when the engine is stopped when the battery is disconnected from the first and second motor sides.

  The hybrid vehicle of the present invention employs the following means in order to achieve the main object described above.

The hybrid vehicle of the present invention
Engine,
A first motor capable of inputting and outputting power;
A planetary gear in which three rotating elements are connected to three axes of a rotating shaft of the first motor, an output shaft of the engine, and a driving shaft coupled to a driving wheel;
A second motor capable of inputting and outputting power to the drive shaft;
A battery capable of exchanging electric power with the first motor and the second motor;
When an abnormality occurs in the battery, the engine and the first motor are connected so that the power from the engine is torque-converted by the first motor and the second motor without charging / discharging the battery and the battery is running. Control means for controlling the first motor and the second motor;
A hybrid vehicle comprising:
When the engine is stopped after the battery-less running, the control means controls the first motor so that the engine speed decreases, and outputs no torque from the second motor. Controlling the second motor so that the electric power obtained by the first motor is consumed by the second motor;
It is characterized by that.

  In the hybrid vehicle of the present invention, when the engine is stopped after the end of the battery-less running, the first motor is controlled so as to reduce the engine speed, and the first motor is not output with torque from the second motor. The second motor is controlled such that the electric power obtained by is consumed by the second motor. Thereby, the rotation speed of the engine can quickly pass through the resonance frequency band. As a result, it is possible to suppress the occurrence of relatively large vibrations in the vehicle. Here, as a method of consuming electric power obtained by the first motor without outputting torque from the second motor by the second motor, it is conceivable to pass a d-axis current to the second motor.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. It is a flowchart which shows an example of the battery abnormal time control routine performed by HVECU70 of an Example. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship between the rotation speed and torque in the rotation element of the planetary gear 30 when ignition is turned off.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50, a system main relay 56, and an electronic control unit for hybrid (hereinafter referred to as a hybrid electronic control unit). , “HVECU”) 70.

  The engine 22 is configured as an internal combustion engine that outputs power using gasoline or light oil as a fuel. The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24.

  Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . Signals from various sensors necessary for controlling the operation of the engine 22 are input to the engine ECU 24 via an input port. Examples of signals from various sensors include the following. A crank angle θcr from a crank position sensor 23 that detects the rotational position of the crankshaft 26 of the engine 22. The throttle opening TH from the throttle valve position sensor that detects the throttle valve position. Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 through an output port. Examples of various control signals include the following. Control signal to the fuel injection valve. Control signal to the throttle motor that adjusts the throttle valve position. Control signal to the ignition coil integrated with the igniter. The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 controls the operation of the engine 22 by a control signal from the HVECU 70. Further, the engine ECU 24 outputs data relating to the operating state of the engine 22 to the HVECU 70 as necessary. The engine ECU 24 calculates the rotation speed of the crankshaft 26, that is, the rotation speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 23.

  The planetary gear 30 is configured as a single pinion type planetary gear mechanism. The sun gear of planetary gear 30 is connected to the rotor of motor MG1. The ring gear of the planetary gear 30 is connected to a drive shaft 36 connected to drive wheels 38a and 38b via a differential gear 37 and a rotor of the motor MG2. A crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30.

  The motor MG1 is configured as a synchronous generator motor, for example. As described above, the motor MG1 has a rotor connected to the sun gear of the planetary gear 30. The motor MG2 is configured as, for example, a synchronous generator motor. In the motor MG2, the rotor is connected to the drive shaft 36 as described above. The inverters 41 and 42 are connected to the power line 54 together with the battery 50. A capacitor 58 is attached to the power line 54. The motors MG1 and MG2 are driven to rotate by switching control of a plurality of switching elements (not shown) of the inverters 41 and 42 by a motor electronic control unit (hereinafter referred to as “motor ECU”) 40.

  Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . Signals from various sensors necessary for driving and controlling the motors MG1, MG2 are input to the motor ECU 40 via the input port. Examples of signals from various sensors include the following. Rotation positions θm1 and θm2 from rotation position detection sensors 43 and 44 that detect the rotation positions of the rotors of the motors MG1 and MG2. Phase current from a current sensor that detects current flowing in each phase of motors MG1 and MG2. The motor ECU 40 outputs a switching control signal to a switching element (not shown) of the inverters 41 and 42 through an output port. The motor ECU 40 is connected to the HVECU 70 via a communication port. The motor ECU 40 controls driving of the motors MG1 and MG2 by a control signal from the HVECU 70. In addition, motor ECU 40 outputs data relating to the driving state of motors MG1 and MG2 to HVECU 70 as necessary. The motor ECU 40 calculates the rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2 from the rotational position detection sensors 43, 44.

  The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydride secondary battery. As described above, the battery 50 is connected to the power line 54 together with the inverters 41 and 42. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52. A system main relay 56 is attached to the power line 54, and the battery 50 can be connected to or disconnected from the inverters 41 and 42 by turning the system main relay 56 on and off.

  Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 via the input port. Examples of signals from various sensors include the following. The battery voltage Vb from the voltage sensor installed between the terminals of the battery 50. Battery current Ib from a current sensor attached to the output terminal of battery 50 (a positive value when discharging from battery 50). Battery temperature Tb from a temperature sensor attached to the battery 50. The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 outputs data relating to the state of the battery 50 to the HVECU 70 as necessary. Battery ECU 52 calculates power storage rate SOC based on the integrated value of battery current Ib from the current sensor. The storage ratio SOC is a ratio of the capacity of power that can be discharged from the battery 50 to the total capacity of the battery 50. Further, the battery ECU 52 calculates the input / output limits Win, Wout based on the calculated storage ratio SOC and the battery temperature Tb from the temperature sensor. The input / output limits Win and Wout are the maximum allowable power that may charge / discharge the battery 50.

  Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. Signals from various sensors are input to the HVECU 70 via input ports. Examples of signals from various sensors include the following. An ignition signal from the ignition switch 80. A shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81. Accelerator opening degree Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83. The brake pedal position BP from the brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85. Vehicle speed V from the vehicle speed sensor 88. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port. The HVECU 70 exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52.

In the hybrid vehicle 20 of the embodiment thus configured, the required driving force of the drive shaft 36 is set based on the accelerator opening Acc and the vehicle speed V, and the required power corresponding to the required driving force is output to the drive shaft 36. In addition, the engine 22 and the motors MG1, MG2 are controlled to operate. As operation modes of the engine 22 and the motors MG1, MG2, there are the following modes (1) to (3).
(1) Torque conversion operation mode: The operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is transmitted to the planetary gear 30 and the motors MG1, MG2. Is a mode in which the motors MG1 and MG2 are driven and controlled so that the torque is converted by the motor and the required power is output to the drive shaft.
(2) Charging / discharging operation mode: The engine 22 is operated and controlled so that the power corresponding to the sum of the required power and the power required for charging / discharging the battery 50 is output from the engine 22, and the power output from the engine 22 In which all or a part of the motor is torque-converted by the planetary gear 30 and the motors MG1 and MG2 with charging and discharging of the battery 50, and the motors MG1 and MG2 are driven and controlled so that the required power is output to the drive shaft 36. .
(3) Motor operation mode: Mode in which the operation of the engine 22 is stopped and the motor MG2 is driven and controlled so that the required power is output to the drive shaft 36.

  Next, the operation of the hybrid vehicle 20 of the embodiment thus configured, particularly the operation when an abnormality has occurred in the battery 50 will be described. FIG. 2 is a flowchart illustrating an example of a battery abnormality control routine executed by the HVECU 70 of the embodiment. This routine is executed when an abnormality occurs in the battery 50.

  When the battery abnormality control routine is executed, the HVECU 70 first turns off the system main relay 56 (step S100). Thereby, the battery 50 is disconnected from the inverters 41 and 42.

  Next, it is determined whether or not it is possible to shift to battery-less travel (step S110). When it is determined that it is not possible to shift to battery-less travel, battery-less travel is not performed and this routine is terminated. Here, the determination as to whether or not it is possible to shift to battery-less traveling is performed by determining whether or not the engine 22 is in operation and whether or not the motor MG2 is operating normally. Battery-less travel will be described later.

  If it is determined in step S110 that it is possible to shift to battery-less travel, battery-less travel is performed (step S120). The battery-less travel is performed by driving and controlling the engine 22 and the motors MG1 and MG2 in the state where the battery 50 is disconnected from the inverters 41 and 42 as in the above-described torque conversion operation mode.

  Next, it is determined whether or not the ignition is turned off (step S130). If it is determined that the ignition is not turned off, the process returns to step S120. In this way, the battery-less running is performed until the ignition is turned off. Whether or not the ignition has been turned off can be determined using an ignition signal from the ignition switch 80.

  If it is determined in step S130 that the ignition is turned off, a fuel injection and ignition stop command for engine 22 is transmitted to engine ECU 24 (step S140). When the engine ECU 24 receives this stop command, the engine ECU 24 stops fuel injection and ignition. Note that when the ignition is turned off, basically, the rotation of the drive wheels 38a, 38b and hence the drive shaft 36 is restricted by the shift position SP being set to the parking position or the brake pedal position BP being depressed. ing.

  Next, the target torque for stop Tstop * is set to the torque command Tm1 * for the motor MG1 (step S150). Here, the stop target torque Tstop * is a torque to be output from the motor MG1 in order to quickly reduce the engine speed Ne, and in the embodiment, the engine speed Ne and the stop target torque Tstop. The relationship with * is determined in advance and stored in a ROM (not shown) as a map, and when the engine speed Ne is given, the corresponding stop target torque Tstop * is derived and set from this map. .

  When torque command Tm1 * for motor MG1 is set, the set torque command Tm1 * and the discharge command for motor MG2 are transmitted to motor ECU 40 (step S170). When the motor ECU 40 receives the torque command Tm1 * and the discharge command of the motor MG2, the motor ECU 40 performs switching control of a plurality of switching elements of the inverter 41 so that the motor MG1 is driven by the torque command Tm1 *, and by driving the motor MG1. Switching control of the plurality of switching elements of the inverter 42 is performed so that the obtained electric power is discharged without outputting torque from the motor MG2. Specifically, the drive control of the motor MG2 is performed by controlling the inverter 42 so that the d-axis current (and the q-axis current of value 0) corresponding to the electric power obtained by driving the motor MG1 is supplied to the motor MG2. Is done by. With such drive control of the motors MG1 and MG2, the rotational speed Ne of the engine 22 can be quickly reduced by the torque from the motor MG1, and the electric power obtained by the motor MG1 can be reduced by the motor MG2 without outputting the torque from the motor MG2. It can be consumed as heat. As a result, it is possible to suppress the time required for the engine speed Ne to pass through a resonance frequency band (for example, 400 rpm to 600 rpm, etc.) and to suppress the occurrence of relatively large vibrations in the vehicle. it can. At this time, an increase in the voltage of the power line 54 (the voltage of the capacitor 58) can be suppressed. At this time, as described above, since the rotation of the drive shaft 36 is limited, the torque from the motor MG2 (the torque output from the motor MG1 and acting on the drive shaft 36 via the planetary gear 30 is canceled). Torque) does not have to be output.

  Next, the rotational speed Ne of the engine 22 is input (step S170), the rotational speed Ne of the engine 22 is compared with the value 0 (step S180), and when the rotational speed Ne of the engine 22 is not 0, step S150 is performed. Return to. Then, the processes of step S150 to step S180 are repeatedly executed, and when the rotation speed Ne of the engine 22 becomes 0, it is determined that the rotation of the engine 22 has stopped, and this routine is ended. Here, the rotation speed Ne of the engine 22 is calculated by the engine ECU 24 and input by communication.

  FIG. 3 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the rotational speed and torque in the rotating elements (sun gear, ring gear, planetary carrier) of the planetary gear 30 when the ignition is turned off. In the figure, the S axis indicates the rotation speed Ns of the sun gear which is the rotation speed Nm1 of the motor MG1, the C axis indicates the rotation speed Nc of the planetary carrier which is the rotation speed Ne of the engine 22, and the R axis indicates the rotation speed of the motor MG2. The rotational speed Nr of the drive shaft 32 which is Nm2 is shown. At this time, basically, the rotation of the drive wheels 38a and 38b and thus the drive shaft 36 is restricted by the shift position SP being set to the parking position or the brake pedal position BP being depressed. When the ignition is turned off, the fuel injection and ignition of the engine 22 are stopped. As shown in the figure, when the rotational speed Ne of the engine 22 is reduced by outputting torque in the direction of decreasing the rotational speed Ne of the engine 22 (downward torque in the S axis in the figure) from the motor MG1. The resonance frequency band of the engine 22 can be passed quickly. Thereby, it can suppress that a comparatively big vibration arises in a vehicle. Further, the electric power obtained by outputting the torque Tm1 from the motor MG1 is consumed as heat without outputting the torque from the motor MG2 by causing the d-axis current to flow through the motor MG2.

  In the hybrid vehicle 20 of the embodiment described above, when the engine 22 is stopped after the end of the battery-less running, the inverter 41 is set so that the motor MG1 is driven by the torque command Tm1 * in order to reduce the rotational speed Ne of the engine 22. Control. Then, the inverter 42 is controlled such that the electric power obtained by the motor MG1 without being output from the motor MG2 is consumed by the motor MG2. Thereby, when the engine 22 is stopped when the battery 50 is disconnected from the inverters 41 and 42, it is possible to suppress a relatively large vibration from being generated in the vehicle.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to the “engine”, the motor MG1 corresponds to the “first motor”, the planetary gear 30 corresponds to the “planetary gear”, the motor MG2 corresponds to the “second motor”, and the battery 50 Corresponds to the “battery”, and the HVECU 70, the engine ECU 24, and the motor ECU 40 correspond to the “control unit”.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. In other words, the interpretation of the invention described in the column of means for solving the problem should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problem. It is only a specific example.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of hybrid vehicles.

  20 Hybrid Vehicle, 22 Engine, 23 Crank Position Sensor, 24 Electronic Control Unit for Engine (Engine ECU), 26 Crankshaft, 30 Planetary Gear, 36 Drive Shaft, 37 Differential Gear, 38a, 38b Drive Wheel, 40 Electronic Control Unit for Motor (Motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 52 electronic control unit for battery (battery ECU), 54 power line, 56 system main relay, 58 capacitor, 70 electronic control unit for hybrid (HV ECU), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal 86, brake pedal position sensor, 88 vehicle speed sensor, MG1, MG2 motor.

Claims (1)

Engine,
A first motor capable of inputting and outputting power;
A planetary gear in which three rotating elements are connected to three axes of a rotating shaft of the first motor, an output shaft of the engine, and a driving shaft coupled to a driving wheel;
A second motor capable of inputting and outputting power to the drive shaft;
A battery capable of exchanging electric power with the first motor and the second motor;
When an abnormality occurs in the battery, the engine and the first motor are connected so that the power from the engine is torque-converted by the first motor and the second motor without charging / discharging the battery and the battery is running. Control means for controlling the first motor and the second motor;
A hybrid vehicle comprising:
When the engine is stopped after the battery-less running, the control means controls the first motor so that the engine speed decreases, and outputs no torque from the second motor. Controlling the second motor so that the electric power obtained by the first motor is consumed by the second motor;
A hybrid vehicle characterized by that.

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