JP2011016425A - Hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve energy efficiency of a vehicle by suppressing operation of an internal combustion engine for charging an electricity accumulation means during stop of the vehicle.SOLUTION: When a stop charge ratio Ps which is a ratio of a stop charging current integrated value Is to the sum of a steady charging current integrated value Id, a deceleration charging current integrated value Ib and a stop charging current integrated value Is within a predetermined time tref is higher than a first threshold Pref and lower than a second threshold Pref2, a change rate α is set to 1 and a distribution ratio setting map is not changed. When the stop charge ratio Ps is higher than the second threshold Pref2, the change rate α is set to a value larger than 1 and the distribution ratio setting map is changed, so that a ratio of a required regenerative braking force RBF* to a required braking force BF* becomes larger.

Description

  The present invention relates to a hybrid vehicle.

  Conventionally, as this type of hybrid vehicle, a first motor generator capable of generating electric power using the power from the engine, and decelerating traveling that is power-running controlled to assist the engine when the vehicle starts or travels, and includes when the accelerator is off Some have been proposed that include a second motor generator that is sometimes regeneratively controlled and a battery that is charged by the power generated by the first motor generator or the power from the second motor generator that is regeneratively controlled (for example, a patent). Reference 1). In this hybrid vehicle, the time from when the accelerator pedal is returned by the driver until the start of regenerative control of the second motor generator and the regenerative braking force to be output to the second motor generator depend on the amount of change in the accelerator opening. Therefore, it is possible to generate a braking force that matches the driver's intention.

JP 2007-269095 A

  By the way, the way of operating the accelerator pedal and the brake pedal differs depending on the driver. In the hybrid vehicle as described above, when the driver frequently uses high-speed driving or sudden deceleration, the second motor generator is regeneratively controlled during braking. The resulting power may be insufficient. When the electric power obtained by the regeneration control of the second motor generator is insufficient in this way, the battery is operated with the electric power generated by the first motor generator by operating the engine while the vehicle is stopped in order to secure the remaining capacity of the battery. There is a need to charge, which may deteriorate the fuel consumption of the engine, that is, the energy efficiency of the vehicle.

  The main purpose of the hybrid vehicle of the present invention is to improve the energy efficiency of the vehicle by suppressing the operation of the internal combustion engine for charging the power storage means while the vehicle is stopped.

  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 includes an internal combustion engine, a generator capable of generating electric power using at least part of the power from the internal combustion engine, an electric motor capable of inputting / outputting power to / from a drive shaft, the generator, and the electric motor. Electric storage means capable of exchanging electric power, charging current detection means for detecting the charging current of the electric storage means, vehicle speed detection means for detecting the vehicle speed, and accelerator opening for detecting the accelerator opening according to the accelerator operation by the driver A required regenerative braking force for the electric motor based on the required braking force according to the braking request by the driver, the detected vehicle speed, and a predetermined distribution constraint. Required regenerative braking force setting means for setting the braking force, and when the braking request is made, the set required regenerative braking force is output from the motor, and the required braking force is applied to the vehicle. In the hybrid vehicle and a brake control means for controlling the at least the electric motor the friction brake means to be given,
The charging current in the steady running state of the vehicle is integrated as a charging current integrated value at steady state, the charging current in the deceleration state of the vehicle is integrated as an integrated charging current value in deceleration, and the charging current in the stationary state of the vehicle Charging current integrating means for integrating the charging current integrated value when the vehicle is stopped;
The sum of the steady-state charging current integrated value, the deceleration charging current integrated value, and the stationary charging current integrated value integrated by the charging current integrating means within a predetermined time is calculated, and the calculated sum is A stop-time charge ratio calculation means for calculating a stop-time charge ratio that is a ratio of the stop-time charge current integrated value;
When the calculated stop charging rate is equal to or less than a predetermined threshold, the distribution constraint is not changed, and when the stopped charging rate is greater than a predetermined threshold, the required regenerative braking force relative to the required braking force is not changed. The gist of the present invention is to provide distribution constraint changing means for changing the distribution constraint so that the ratio increases.

  In the vehicle of the present invention, the required regenerative braking force for the motor is set based on the required braking force according to the braking request from the driver, the vehicle speed, and the predetermined distribution constraint. In addition, the charging current of the power storage means in the steady running state of the vehicle is integrated as an accumulated charge current value in the steady state, the charging current of the storage means in the deceleration state of the vehicle is integrated as the integrated charging current value in the deceleration state, and The charge current of the power storage means is integrated as a charge current integrated value during stoppage, and the sum of the charge current integrated value during steady state, the charge current integrated value during deceleration, and the charge current integrated value during stop is calculated. Then, a stop-time charge ratio, which is a ratio of the stop-time charge current integrated value to the calculated sum, is calculated. When the calculated stop charging rate is equal to or less than the predetermined threshold, the distribution constraint is not changed, and when the stopped charging rate is greater than the predetermined threshold, the ratio of the required regenerative braking force to the required braking force is large. Change the distribution constraint so that As a result, even when high-speed traveling or sudden deceleration is frequently used, it is possible to satisfactorily ensure the electric power obtained by performing regenerative control of the motor during braking. Therefore, it becomes possible to suppress the operation of the generator for charging the power storage means while the vehicle is stopped, that is, the operation of the internal combustion engine, and the fuel efficiency, that is, the energy efficiency of the internal combustion engine can be improved.

1 is a schematic configuration diagram of a hybrid vehicle 20 according to an embodiment of the present invention. It is explanatory drawing which shows an example of the map for distribution ratio setting. It is a flowchart which shows an example of the change rate setting routine performed by hybrid ECU70 of an Example.

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

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle 20 according to an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22 that uses gasoline, light oil, or the like as fuel, an engine electronic control unit (hereinafter referred to as “engine ECU”) 24 that drives and controls the engine 22, and an engine 22. A planetary gear 30 in which a carrier 34 is connected to a crankshaft 26 as an output shaft via a damper 28, a motor MG 1 capable of generating power connected to a sun gear 31 of the planetary gear 30, and a drive connected to a ring gear 32 of the planetary gear 30. A reduction gear 35 connected to a ring gear shaft 32a as a shaft, a motor MG2 connected to the ring gear shaft 32a via the reduction gear 35, and a gear mechanism 37 and a differential gear 38 connected to the ring gear shaft 32a. Drive wheels 39a, 39b, motor MG1, and Inverter 41 interposed between power line 54, inverter 42 interposed between motor MG2 and power line 54, and a motor for driving and controlling motors MG1 and MG2 via inverters 41 and 42 An electronic control unit (hereinafter referred to as “motor ECU”) 40, a battery 50 connected to an electric power line 54, for example, a lithium ion secondary battery or a nickel hydride secondary battery, and a battery electronic control unit that manages the battery 50 (Hereinafter referred to as “battery ECU”) 52, a hybrid electronic control unit (hereinafter referred to as “hybrid ECU”) 70 that controls the entire vehicle while communicating with engine ECU 24, motor ECU 40, and battery ECU 52, and friction braking force An electronically controlled hydraulic brake unit that can output And a brake unit "hereinafter) 90 and the like.

  The motor ECU 40 calculates data related to the motors MG1 and MG2, such as the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2. The battery ECU 52 is attached to a signal necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between the terminals of the battery 50, and a power line connected to the output terminal of the battery 50. The charging / discharging current I from the current sensor 55 and the battery temperature from a temperature sensor (not shown) attached to the battery 50 are input. Then, in order to manage the battery 50, the battery ECU 52 calculates the remaining capacity SOC of the battery 50, or calculates the charge / discharge required power Pb * of the battery 50 based on the remaining capacity SOC and predetermined charge / discharge constraints. Or the input limit Win as the allowable charging power that is the power allowed for charging the battery 50 based on the remaining capacity SOC of the battery 50 and the temperature of the battery 50 and the allowable discharge that is the power allowed for discharging the battery 50. The output limit Wout as power is calculated.

  The hybrid ECU 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 that stores a processing program, a RAM 76 that temporarily stores data, and a timer that executes a timing process in response to a timing command. 78, and an input / output port and a communication port (not shown). The hybrid ECU 70 includes 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, and an accelerator opening from the accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The degree Acc, the brake pedal stroke BS from the brake pedal stroke sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. As described above, the hybrid ECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52.

  The brake unit 90 is attached to the brake master cylinder 91, the hydraulic (hydraulic pressure) brake actuator 92, the drive wheels 39a and 39b, and the driven wheels (not shown), and holds the brake disk to apply friction braking force to the corresponding wheels. Brake wheel cylinder pressure sensors 94a to 94d for detecting the hydraulic pressure (brake wheel cylinder pressure) of the brake wheel cylinders provided for each of the brake wheel cylinders 93a to 93d and the brake wheel cylinders 93a to 93d for driving the brake pads that can be applied. , A brake electronic control unit (hereinafter referred to as “brake ECU”) 95 for controlling the brake actuator 92, and the like. The brake actuator 92 is a pump or accumulator as a hydraulic pressure generation source (not shown), a master cylinder cut solenoid valve for controlling the communication state between the brake master cylinder 91 and the brake wheel cylinders 93a to 93d, and a pedal according to the depression amount of the brake pedal 85 A stroke simulator or the like that creates a reaction force against the pedaling force is provided, and a friction braking force can be applied to the drive wheels 39a and 39b and other driven wheels. Further, the brake ECU 95 detects a master cylinder pressure from a master cylinder pressure sensor (not shown), a brake wheel cylinder pressure from the brake wheel cylinder pressure sensors 94a to 94d, and a vehicle speed via a signal line (not shown). A vehicle speed V from the sensor 88, a brake pedal stroke BS from the brake pedal stroke sensor 86, a wheel speed from a wheel speed sensor (not shown), a steering angle from a steering angle sensor (not shown), and the like are input to the hybrid ECU 70 and the like. Various signals are exchanged by communication.

  When the brake pedal 85 is depressed by the driver, the brake ECU 95 uses the brake pedal stroke BS from the brake pedal stroke sensor 86 and a predetermined pedal force setting map (not shown) to be applied to the brake pedal 85 by the driver. A pedaling force Fpd is calculated, and a required braking force BF * required by the driver is set based on the calculated pedaling force Fpd. Further, the brake ECU 95 uses the set required braking force BF *, the vehicle speed V from the vehicle speed sensor 88, and a predetermined distribution ratio setting map, and the required regenerative braking force RBF * (= d × BF *) for the motor MG2. The required friction braking force FBF * (= (1-d) × BF *) for the brake unit 90 is set. Then, the brake ECU 95 transmits the required regenerative braking torque RBT * obtained by multiplying the required regenerative braking force RBF * by a predetermined conversion coefficient to the hybrid ECU 70, and the regenerative braking force actually output that is transmitted from the hybrid ECU 70. The brake unit 90 is controlled so that the friction braking force based on the signal indicating the above and the required friction braking force FBF * acts on the drive wheels 39a and 39b and the driven wheels (not shown). In the embodiment, the distribution ratio setting map is created in advance so as to define the relationship between the distribution ratio d and the vehicle speed V, which is the ratio of the required regenerative braking force RBF * by the motor MG2 to the required braking force BF *. Is stored in a ROM (not shown). FIG. 2 shows an example of the distribution ratio setting map. Note that the distribution ratio setting constraint in FIG. 2 defines the required regenerative braking force RBF * and the required friction braking force FBF * for the sake of simplicity of explanation. Needless to say, the braking force by the brake may be taken into consideration.

  In the hybrid vehicle 20 of the embodiment configured as described above, as a drive shaft connected to the wheels 39a and 39b based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. The required torque Tr * to be output to the ring gear shaft 32a is calculated, and the engine 22, the motor MG1, and the motor MG2 are controlled so that torque based on the required torque Tr * is output to the ring gear shaft 32a. As an operation control mode of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that the engine 22 outputs power corresponding to the required torque Tr * to be output to the ring gear shaft 32a as an axle. Torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that all of the power output from the planetary gear 30, the motor MG1 and the motor MG2 is torque-converted by the planetary gear 30, the motor MG1 and the motor MG2, and the required torque Tr * The engine 22 is operated and controlled so that the power corresponding to the sum of the power required for charging / discharging of the battery 50 is output from the engine 22 and all or the power output from the engine 22 with charging / discharging of the battery 50 is controlled. Part of planetary gear 30 and motor M Charge / discharge operation mode in which the motors MG1 and MG2 are driven and controlled so that torque based on the required torque Tr * is output to the ring gear shaft 32a with torque conversion between the motor 1 and the motor MG2, and the required torque Tr is stopped. There is a motor operation mode in which the motor MG2 is driven and controlled so that torque based on * is output to the ring gear shaft 32a. In the hybrid vehicle 20 of the embodiment, the battery 50 can be charged with the electric power generated by the motor MG1 using the power from the engine 22 by operating the engine 22 in a stopped state.

  Further, in the hybrid vehicle 20, when the accelerator pedal 83 is released, the accelerator is off (Acc = 0%), or when the accelerator pedal 83 is released and the brake pedal 85 is depressed, By adding the required regenerative braking torque RBT * (value 0 when the accelerator is off) received from the brake ECU 95 to the base torque Tb set as the torque to be output to the ring gear shaft 32a as the axle based on the vehicle speed V when the accelerator is off. The required torque Tr * is set. In the embodiment, the relationship between the vehicle speed V and the base torque Tb is determined in advance, and the base torque Tb is stored in the ROM 74 as a base torque setting map (not shown). The base torque Tb corresponding to the given vehicle speed V is Derived and set from the map. The torque command Tm1 * indicating the target torque of the motor MG1 and the torque command Tm2 * indicating the target torque of the motor MG2 are input / output of the battery 50 so that torque based on the required torque Tr * is output to the ring gear shaft 32a. It is set within the limits Win and Wout, and is transmitted from the hybrid ECU 70 to the motor ECU 40. Then, motor ECU 40 performs switching control of inverters 41 and 42 such that motors MG1 and MG2 are driven in accordance with torque commands Tm1 * and Tm2 *. The torque command Tm2 * is transmitted from the hybrid ECU 70 to the brake ECU 95 as a signal indicating the regenerative braking force that is actually output.

  Here, in the hybrid vehicle 20 of the embodiment, when the driver frequently uses high-speed traveling, sudden deceleration, or the like, the electric power obtained by regenerative control of the motor MG2 during braking may be insufficient. When the electric power obtained by the regenerative control of the motor MG2 is insufficient in this way, the battery 50 is discharged with the electric power generated by the motor MG1 by operating the engine 22 while the vehicle is stopped to secure the remaining capacity SOC of the battery 50. There is a need to charge the battery, which may deteriorate the fuel efficiency of the engine 22, that is, the energy efficiency of the vehicle. Therefore, in the embodiment, the change rate α is set according to the charge amount of the battery 50 when the hybrid vehicle 20 is stopped, and the distribution ratio setting map is changed based on the set change rate α. Electric power obtained by regenerative control of the motor MG2 can be secured satisfactorily.

Next, a procedure for setting the change rate α will be described. FIG. 3 is a flowchart showing an example of a change rate setting routine executed by the hybrid ECU 70 to set the change rate α. When starting the change rate setting routine of FIG. 3, the CPU 72 of the hybrid ECU 70 first starts the timer 78 (step S100). Then, data necessary for setting the change rate α such as the vehicle speed V from the vehicle speed sensor 88, the accelerator opening Acc from the accelerator pedal position sensor 84, and the charge / discharge current I of the battery 50 is input (step S110). Here, the charge / discharge current I is input from the battery ECU 52 by communication. After the data input process in step S110, it is determined whether the traveling state of the hybrid vehicle 20 is a steady traveling state, a deceleration state, or a stopped state based on the input vehicle speed V and the accelerator opening degree Acc. The charging current I of the battery 50 in the running state is integrated as a steady-state charging current integrated value Id, the charging current I of the battery 50 in the deceleration state is integrated as the charging current integrated value Ib during deceleration, and the charging current of the battery 50 in the stopped state I is integrated as a charge current integrated value Is during stop (step S120). However, in the embodiment, the steady running state is a state where the hybrid vehicle 20 is running at a substantially constant speed, that is, a state where the acceleration of the hybrid vehicle 20 is within a predetermined range (for example, within a range of ± 5 km / sec ² ). Yes, the deceleration state is a state in which the hybrid vehicle 20 is in an accelerator-off state and is decelerating at an acceleration smaller than, for example, −5 km / sec ² , and the stop state is a state in which the hybrid vehicle 20 is stopped. This is a state where the vehicle is traveling at an extremely constant speed close to the value 0.

  Subsequently, it is determined whether or not the elapsed time t counted by the timer 78 exceeds a predetermined time tref (step S130). The predetermined time tref is predetermined as a constant value such as 1 hour. If the elapsed time t is less than or equal to the predetermined time tref, the processes of steps S110 and S120 are repeatedly executed. When it is determined that the elapsed time t exceeds the predetermined time tref, the timer 78 is reset (step S140), and the charging current integration value Id of the battery 50 accumulated at step S120 and the charging current integration during deceleration are integrated. A stop charging rate Ps that is a ratio of the stop charging current integrated value Is to the sum of the value Ib and the stop charging current integrated value Is is calculated (step S150), and the calculated stop charging rate Ps is a first threshold value Pref1. It is determined whether it is within the range from to the second threshold value Pref2 (step S160). However, the second threshold value Pref2 is a predetermined positive value, and the first threshold value Pref1 is a positive value smaller than the second threshold value Pref2. When the stop-time charging rate Ps is equal to or higher than the first threshold value Pref1 and equal to or lower than the second threshold value Pref2, the change rate α is set to a value of 1 in order to continue using the current distribution ratio setting map. Setting is made (step S170). On the other hand, when the stationary charging rate Ps is smaller than the first threshold value Pref1 or larger than the second threshold value Pref2, the change rate α is set based on the stationary charging rate Ps (step S180). In the embodiment, the change rate α is set to a value smaller than the value 1 (for example, 1−Ps / 2) and the second threshold value when the stationary charging rate Ps is smaller than the first threshold value Pref1. When larger than Pref2, it is set to a value larger than value 1 (for example, 1 + Ps / 2). Then, the set change rate α is transmitted to the brake ECU 95 (step S190), and this routine is terminated.

  The brake ECU 95 that has received the change rate α from the hybrid ECU 70 changes the distribution ratio setting map based on the change rate α. Specifically, the change rate α is multiplied by the entire value of the required regenerative braking force RBF * defined by the distribution ratio setting map when the change rate α is received. When the change rate α is a value 1, that is, when the stopping charging rate Ps is equal to or higher than the first threshold value Pref1 and equal to or lower than the second threshold value Pref2, the value of the required regenerative braking force RBF * is not changed, The current distribution ratio setting map is continuously used. Further, when the change rate α is larger than the value 1, that is, when the stopping charging rate Ps is larger than the second threshold value Pref2, the distribution ratio setting map at that time, as shown by a one-dot chain line in FIG. The distribution ratio setting map is changed so that the value of the required regenerative braking force RBF * is increased according to the change rate α (by the ratio Ps / 2). Then, when the change rate α becomes smaller than the value 1, that is, when the stopping charging rate Ps becomes smaller than the first threshold value Pref1, the distribution at that time is shown as shown by a two-dot chain line in FIG. The distribution ratio setting map is changed so that the value of the required regenerative braking force RBF * defined by the ratio setting map decreases according to the change rate α (by the ratio Ps / 2). Thus, in the hybrid vehicle 20 of the embodiment, the distribution ratio setting map is changed so that the ratio of the required regenerative braking force RBF * to the required braking force BF * increases as the stop charging rate Ps increases. . Further, even if the stop-time charging rate Ps once increases, if the stop-time charging rate Ps becomes smaller than the first threshold value Pref1, the ratio of the required regenerative braking force RBF * to the required braking force BF * is reduced. The distribution ratio setting map is changed.

  As described above, in the hybrid vehicle 20 of the embodiment, the required regenerative braking force RBF * for the motor MG2 based on the required braking force BF * according to the driver's braking request, the vehicle speed V, and the distribution ratio setting map. Set. Further, the charging current I of the battery 50 in the steady running state of the hybrid vehicle 20 is integrated as the charging current integrated value Id during normal operation, and the charging current I of the battery 50 in the deceleration state of the hybrid vehicle 20 is used as the charging current integrated value Ib during deceleration. The charging current I of the battery 50 when the hybrid vehicle 20 is stopped is integrated as a charging current integrated value Is when stopped, and the charging current integrated value Id during steady state and the charging current integrated value during deceleration are integrated within a predetermined time tref. The sum of Ib and the stop charging current integrated value Is is calculated, and the stop charging ratio Ps that is the ratio of the stop charging current integrated value Is to the calculated sum is calculated. When the calculated stop charging rate Ps is equal to or higher than the first threshold value Pref1 and equal to or lower than the second threshold value Pref2, the change rate α is set to the value 1 and the distribution ratio setting map is not changed. . On the other hand, when the stopping charging rate Ps is larger than the second threshold value Pref2, the change rate α is set to a value larger than the value 1 so that the ratio of the required regenerative braking force RBF * to the required braking force BF * is increased. Change the distribution ratio setting map. As a result, even when high-speed running or sudden deceleration is frequently used, it is possible to satisfactorily secure the electric power obtained by regeneratively controlling the motor MG2 during braking. Therefore, it becomes possible to suppress the operation of the motor MG1 for charging the battery 50 while the vehicle is stopped, that is, the operation of the engine 22, and to improve the fuel consumption of the engine 22, that is, the energy efficiency. Further, in the embodiment, when the stopping charging rate Ps becomes smaller than the first threshold value Pref1, the change rate α is set to a value smaller than the value 1, and the ratio of the required regenerative braking force RBF * to the required braking force BF *. The distribution ratio setting map is changed so that becomes smaller. Thereby, it can suppress that the ratio of the request | requirement regenerative braking force RBF * with respect to the request | requirement braking force BF * becomes large too much.

  The present invention includes an internal combustion engine, a generator connected to the output shaft of the internal combustion engine, an electric motor capable of inputting / outputting power to / from the drive shaft, and a power storage means capable of exchanging electric power with the generator and the electric motor. The present invention may be applied to a series type hybrid vehicle, or may be applied to a parallel type hybrid vehicle including an internal combustion engine and an electric motor that is connected to an output shaft of the internal combustion engine and capable of inputting and outputting power to a drive shaft. May be. When the present invention is applied to a parallel hybrid vehicle, the electric motor connected to the output shaft of the internal combustion engine functions as both the generator and the electric motor in the present invention.

  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 is applicable to the hybrid vehicle manufacturing industry.

  20 hybrid vehicle, 22 engine, 24 electronic control unit (engine ECU) for engine, 26 crankshaft, 28 damper, 30 planetary gear, 31 sun gear, 32 ring gear, 32a ring gear shaft, 34 carrier, 35 reduction gear, 37 gear mechanism, 38 Differential gear, 39a-39b wheel, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 52 battery electronic control unit (battery ECU), 54 power line, 55 current sensor, 70 electronic control unit for hybrid (hybrid ECU), 72 CPU, 74 ROM, 76 RAM, 78 timer, 80 ignition switch, 81 shift lever, 82 Shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal stroke sensor, 87 vehicle speed sensor, 90 electronically controlled hydraulic brake unit (brake unit), 91 brake master cylinder, 92 brake actuator, 93a -93d Brake wheel cylinder, 94a-94d Brake wheel cylinder pressure sensor, 95 Electronic control unit for brake (brake ECU), MG1, MG2 motor.

Claims (1)

An internal combustion engine, a generator capable of generating electric power using at least part of the power from the internal combustion engine, an electric motor capable of inputting / outputting power to / from a drive shaft, and an electric storage capable of exchanging electric power with the generator and the electric motor Means, a charging current detecting means for detecting a charging current of the power storage means, a vehicle speed detecting means for detecting a vehicle speed, an accelerator opening detecting means for detecting an accelerator opening corresponding to an accelerator operation by a driver, and a friction control. Friction braking means capable of outputting power, required regenerative braking force for setting a required regenerative braking force for the electric motor based on a required braking force according to a braking request by a driver, the detected vehicle speed, and a predetermined distribution constraint Setting means, and when the braking request is made, the set required regenerative braking force is output from the electric motor and at least before the requested braking force is applied to the vehicle. In the hybrid vehicle and a brake control means for controlling the electric motor the friction braking means,
The charging current in the steady running state of the vehicle is integrated as a charging current integrated value at steady state, the charging current in the deceleration state of the vehicle is integrated as an integrated charging current value in deceleration, and the charging current in the stationary state of the vehicle Charging current integrating means for integrating the charging current integrated value when the vehicle is stopped;
The sum of the steady-state charging current integrated value, the deceleration charging current integrated value, and the stationary charging current integrated value integrated by the charging current integrating means within a predetermined time is calculated, and the calculated sum is A stop-time charge ratio calculation means for calculating a stop-time charge ratio that is a ratio of the stop-time charge current integrated value;
When the calculated stop charging rate is equal to or less than a predetermined threshold, the distribution constraint is not changed, and when the stopped charging rate is greater than a predetermined threshold, the required regenerative braking force relative to the required braking force is not changed. A hybrid vehicle comprising: distribution restriction changing means for changing the distribution restriction so that the ratio increases.

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