JP4784300B2 - Automobile and control method thereof - Google Patents

Description

  The present invention relates to an automobile and a control method thereof.

Conventionally, this type of automobile is provided with an engine that outputs power to the axle and a hydraulic brake, and even if the driver releases the brake pedal while the vehicle is stopped, the brake hydraulic pressure is maintained and the braking force on the axle is maintained. Has been proposed to perform a brake automatic continuation function in which the brake is released and the vehicle starts when the accelerator pedal is stepped on (see, for example, Patent Document 1). In this automobile, since the brake is released while outputting power from the engine that does not slip down when starting on a slope, it is possible to suppress the slope down.
JP-A-7-144625

  However, in the above-described automobile, even if the brake is released, the brake hydraulic pressure response is low, so the braking force on the axle is not released instantaneously. If power is output from the engine to the axle in such a state, the brake will be dragged and noise will be generated. It is desirable that such abnormal noise be suppressed as much as possible in order to make the driver feel uncomfortable.

  One object of the vehicle and the control method thereof according to the present invention is to suppress the generation of abnormal noise due to brake drag when starting. Another object of the present invention is to output power based on a driving request from a driver to an axle more quickly while suppressing the generation of abnormal noise.

  In order to achieve at least a part of the above object, the automobile of the present invention and the control method thereof employ the following means.

The automobile of the present invention
A power source capable of outputting power to the axle,
A braking force that operates using a pressurized working fluid and applies a braking force to the axle based on a driver's braking request operation and can apply the braking force to the axle regardless of the driver's braking request operation. Granting means;
Drive request detection means for detecting a drive request by the driver;
When a drive request by the driver is detected by the drive request detection means while the vehicle is stopped while a braking force is being applied to the axle by the braking force applying means in a state where no braking request operation has been performed by the driver The braking force applied by the braking force applying means is released, and less power than the detected driving request is output to the axle until a waiting time based on the detected driving request elapses. The braking force applying means and the power source are controlled so that the power based on the detected driving request is output to the axle after the waiting time has elapsed. Control means for controlling
It is a summary to provide.

  In the automobile according to the present invention, when the driver requests driving while the vehicle is stopped while the braking force is applied to the axle by the braking force applying means in a state where the driver does not perform the braking request operation, the control is performed. The braking force applying means and the power source are applied so that less power than the power based on the driving request is output to the axle until the application of the braking force by the power applying means is canceled and the waiting time based on the driving request by the driver elapses. After the elapse of the waiting time, the braking force applying means and the power source are controlled so that the power based on the driving request by the driver is output to the axle. Since the braking force applied by the braking force applying means is released and the waiting time based on the driving request by the driver has elapsed, less power than the driving request is output to the axle. Even when the braking force is low, dragging of the braking force applying means can be suppressed. As a result, the generation of abnormal noise can be suppressed. In addition, since the power based on the driving request by the driver is output to the axle after the waiting time based on the driving request by the driver has elapsed, the power based on the driving request can be more promptly after the waiting time has elapsed. Can be output to the axle.

  In such an automobile of the present invention, when the detected drive request is less than a predetermined request, the control means is less than the power based on the detected drive request until a waiting time based on the detected drive request elapses. The braking force applying means and the power source are controlled so that power is output to the axle, and based on the detected drive request without waiting for the waiting time when the detected drive request is greater than a predetermined request. It may be a means for controlling the braking force applying means and the power source so that power is output to the axle. When the drive request is less than the predetermined request, since less power than the power based on the drive request is output to the axle until the waiting time elapses, it is possible to suppress the generation of noise due to the drag of the braking force applying means. Further, when the drive request is larger than the predetermined request, the power based on the driver's drive request is output to the axle without waiting for the waiting time, so that the power based on the drive request can be quickly output to the axle.

  The automobile according to the present invention further includes a slope detection means for detecting a slope in the front-rear direction of the automobile, and the waiting time is a time based on the detected drive request and the detected slope. You can also. In this way, it is possible to suppress the automobile from sliding down.

  The automobile of the present invention further includes a switch operation detecting means for detecting an operation of a predetermined switch, and the control means performs a braking request operation by a driver when the operation of the predetermined switch is detected by the switch operation detecting means. It is also possible to control the braking force applying means so that a braking force is applied to the axle in a state in which no braking is performed. In this way, when a predetermined switch operation is detected, a braking force can be applied to the axle in a state where the driver has not performed a braking request operation.

  Alternatively, the automobile of the present invention may include at least one of an internal combustion engine and an electric motor as the power source.

The method for controlling an automobile of the present invention includes:
A power source capable of outputting power to the axle, and a pressurized working fluid that operates to apply braking force to the axle based on a driver's braking request operation, and regardless of the driver's braking request operation. A braking force applying means capable of applying a braking force to an axle;
When a drive request by the driver is detected by the drive request detection means while the vehicle is stopped while a braking force is being applied to the axle by the braking force applying means in a state where no braking request operation has been performed by the driver The braking force is applied so that less power than the power based on the driving request is output to the axle until the application of the braking force by the braking force applying means is released and a waiting time based on the driving request by the driver elapses. The present invention is directed to controlling the applying means and the power source, and controlling the braking force applying means and the power source so that power based on the drive request is output to the axle after the waiting time has elapsed. And

  In the vehicle control method of the present invention, the driver requests driving while the vehicle is stopped while the braking force is applied to the axle by the braking force applying means in a state where the driver does not perform the braking request operation. Sometimes, the braking force applying means is released so that less power than the power based on the driving request is output to the axle until the waiting time based on the driving request by the driver elapses after the braking force applying means is released. After the waiting time has elapsed, the braking force applying means and the power source are controlled so that the power based on the driving request by the driver is output to the axle. Since the braking force applied by the braking force applying means is released and the waiting time based on the driving request by the driver has elapsed, less power than the driving request is output to the axle. Even when the braking force is low, dragging of the braking force applying means can be suppressed. As a result, the generation of abnormal noise can be suppressed. In addition, since the power based on the driving request by the driver is output to the axle after the waiting time based on the driving request by the driver has elapsed, the power based on the driving request can be more promptly after the waiting time has elapsed. Can be output to the axle.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 equipped with a power output apparatus according to an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30, a motor MG2 connected to the reduction gear 35, A brake actuator 92 for controlling the brakes of the drive wheels 63a and 63b and a driven wheel (not shown) and a hybrid electronic control unit 70 for controlling the entire power output apparatus are provided.

  The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit (hereinafter referred to as an engine ECU) that receives signals from various sensors that detect the operating state of the engine 22. ) 24 is subjected to operation control such as fuel injection control, ignition control, intake air amount adjustment control and the like. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and, if necessary, transmits data related to the operating state of the engine 22 to the hybrid electronic control. Output to unit 70.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62.

  The motor MG1 and the motor MG2 are both configured as well-known synchronous generator motors that can be driven as generators and can be driven as motors, and exchange power with the battery 50 via inverters 41 and 42. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive electrode bus and a negative electrode bus shared by the inverters 41 and 42, and the electric power generated by one of the motors MG1 and MG2 It can be consumed by a motor. Therefore, battery 50 is charged / discharged by electric power generated from one of motors MG1 and MG2 or insufficient electric power. If the balance of electric power is balanced by the motors MG1 and MG2, the battery 50 is not charged / discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 detects signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and current sensors (not shown). The phase current applied to the motors MG1 and MG2 to be applied is input, and a switching control signal to the inverters 41 and 42 is output from the motor ECU 40. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70.

  The battery 50 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input. Output to the control unit 70. The battery ECU 52 also calculates the remaining capacity (SOC) based on the integrated value of the charge / discharge current detected by the current sensor in order to manage the battery 50.

  The brake actuator 92 has a braking torque according to the share of the brake in the braking force applied to the vehicle by the pressure (brake pressure) of the brake master cylinder 90 and the vehicle speed V generated in response to the depression of the brake pedal 85. The brake wheel cylinders 96a and 96d are adjusted so as to act on the driven wheel 63b and a driven wheel (not shown), and the braking torque is applied to the drive wheels 63a and 63b and the driven wheel regardless of the depression of the brake pedal 85. The hydraulic pressures of 96a to 96d can be adjusted. The brake actuator 92 is controlled by a brake electronic control unit (hereinafter referred to as a brake ECU) 94. The brake ECU 94 inputs signals such as a wheel speed from a wheel speed sensor (not shown) attached to the driving wheels 63a and 63b and the driven wheel and a steering angle from a steering angle sensor (not shown) by a signal line (not shown). When the driver depresses the brake pedal 85, an anti-lock brake system function (ABS) that prevents any of the driving wheels 63a, 63b and the driven wheels from slipping due to the lock or when the driver depresses the accelerator pedal 83 Traction control (TRC) for preventing any one of the drive wheels 63a and 63b from slipping due to idling, posture holding control (VSC) for holding the posture while the vehicle is turning, and the like are also performed. The brake ECU 94 also performs an automatic brake continuation function that maintains braking torque that acts on the drive wheels 63a and 63b and the driven wheels even when the driver releases the brake pedal 85 while the vehicle is stopped. The brake ECU 94 communicates with the hybrid electronic control unit 70, and controls the drive of the brake actuator 92 by a control signal from the hybrid electronic control unit 70, and the data regarding the state of the brake actuator 92 is used for the hybrid as necessary. Output to the electronic control unit 70.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The accelerator pedal position Acc from the brake pedal, the brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, the operation signal from the brake automatic continuation function operation switch 87 for turning on / off the brake automatic continuation function, the vehicle speed The vehicle speed V from the sensor 88, the gradient θ from the gradient sensor 89 that detects the gradient in the longitudinal direction of the vehicle, and the like are input via the input port. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, the battery ECU 52, and the brake ECU 94 via a communication port, and the engine ECU 24, the motor ECU 40, the battery ECU 52, the brake ECU 94, and various control signals. And exchanging data.

  The hybrid vehicle 20 of the embodiment thus configured calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, 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 the power distribution and integration mechanism 30. Torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that the torque is converted by the motor MG1 and the motor MG2 and output to the ring gear shaft 32a, and the required power and the power required for charging and discharging the battery 50. The engine 22 is operated and controlled so that suitable power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution and integration mechanism 30, the motor MG1, and the motor. The required power is converted to the ring gear shaft 32 with torque conversion by MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled to be output to each other, and a motor operation mode in which the operation of the engine 22 is stopped and the power corresponding to the required power from the motor MG2 is output to the ring gear shaft 32a. and so on.

  Next, even if the operation of the hybrid vehicle 20 of the embodiment thus configured, in particular, the brake automatic continuation function operation switch 87 is turned on by the driver and the driver releases the brake pedal 85 while the vehicle is stopped, the driving wheel 63a is driven. , 63b and the operation when starting at the request of the driver while the automatic brake continuation function for holding the braking torque acting on the driven wheel is being performed. FIG. 2 is a flowchart showing an example of a start time control routine executed by the hybrid electronic control unit 70. In this routine, the brake pedal 94 is detected so as to release the braking torque acting on the drive wheels 63a and 63b and the driven wheels when the driver depresses the accelerator pedal 83 while the automatic brake continuation function is being performed. It is assumed that it is executed immediately after the cancellation instruction is given, and is repeatedly executed every predetermined time (for example, every several msec). The brake ECU 94 that has received the brake release instruction drives and controls the brake actuator 92 so as to release the hydraulic pressure of the brake wheel cylinders 96a to 96d and release the braking torque acting on the drive wheels 63a and 63b and the driven wheels.

  When the start time control routine is executed, the CPU 72 of the hybrid electronic control unit 70 firstly, the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speed Nm1 of the motors MG1 and MG2. , Nm2, the rotational speed Ne of the engine 22, the input / output limits Win and Wout of the battery 50, the gradient θ from the gradient sensor 89, the waiting time tb after the brake release instruction is given to the brake ECU 94, etc. Is input (step S100). Here, the rotation speed Ne of the engine 22 is calculated based on a signal from a crank position sensor 23a attached to the crankshaft 26, and is input from the engine ECU 24 by communication. Further, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication from those calculated based on the rotational positions of the rotors of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44. It was supposed to be. Further, the input / output limits Win and Wout of the battery 50 are set based on the battery temperature Tb of the battery 50 detected by the temperature sensor 51 and the remaining capacity (SOC) of the battery 50 from the battery ECU 52 by communication. To do. As the waiting time tb, a time measured by a timer (not shown) from when the brake ECU 94 is instructed to release the brake is input.

  When the data is input in this manner, whether or not the waiting time tb has passed the time tref until the hydraulic pressure of the brake wheel cylinders 96a to 96d becomes sufficiently low (step S110), and the accelerator opening degree Acc has a large driving request from the driver. It is determined whether or not the accelerator opening threshold value Accth is smaller than that (step S120), and whether or not the gradient θ is smaller than the threshold value θth of the gradient in which the vehicle slides down the slope if power is not quickly output to the ring gear shaft 32a. (Step S130). When the waiting time tb has passed the time tref (step S110), it is determined that the hydraulic pressures in the brake wheel cylinders 96a to 96d are sufficiently low, and the process proceeds to step S140. Further, even when the waiting time tb has not passed the time tref and the hydraulic pressure of the brake wheel cylinders 96a to 96d is not sufficiently low, the accelerator opening Acc is equal to or greater than the threshold value Accth, and the driver's drive request is large and the ring gear shaft When it is better to quickly output the power based on the driving request by the driver to 32a (step S120), or when the gradient θ is equal to or greater than the threshold θth and the vehicle will slide down unless the power is quickly output to the ring gear shaft 32a (step S130). ), The process proceeds to step S140.

  In the process of step S140, the required torque Tr * to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V. And the required power Pe * required for the engine 22 is set (step S140). In the embodiment, the required torque Tr * is determined in advance by storing the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tr * in the ROM 74 as a required torque setting map, and the accelerator opening Acc, the vehicle speed V, , The corresponding required torque Tr * is derived and set from the stored map. FIG. 3 shows an example of the required torque setting map. The required power Pe * can be calculated as the sum of the set required torque Tr * multiplied by the rotational speed Nr of the ring gear shaft 32a and the charge / discharge required power Pb * required by the battery 50 and the loss Loss. The rotation speed Nr of the ring gear shaft 32a can be obtained by multiplying the vehicle speed V by the conversion factor k, or can be obtained by dividing the rotation speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35.

  Subsequently, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on the set required power Pe * (step S170). In this setting, the target rotational speed Ne * and the target torque Te * are set based on the operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 4 shows an example of the operation line of the engine 22 and how the target rotational speed Ne * and the target torque Te * are set. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained from the intersection of the operation line and a curve with a constant required power Pe * (Ne * × Te *).

  Next, using the set target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ of the power distribution and integration mechanism 30, the target rotational speed Nm1 of the motor MG1 is given by the following equation (1). * Is calculated and a torque command Tm1 * of the motor MG1 is calculated by equation (2) based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1 (step S180). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 5 is a collinear diagram showing a dynamic relationship between the number of rotations and torque in the rotating elements of the power distribution and integration mechanism 30. In the figure, the left S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor MG1, the C-axis indicates the rotation speed of the carrier 34 that 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 ring gear 32 obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. Expression (1) can be easily derived by using this alignment chart. The two thick arrows on the R axis indicate that torque Te * output from the engine 22 when the engine 22 is normally operated at the operation point of the target rotational speed Ne * and the target torque Te * is transmitted to the ring gear shaft 32a. Torque and torque that the torque Tm2 * output from the motor MG2 acts on the ring gear shaft 32a via the reduction gear 35. Expression (2) is a relational expression in feedback control for rotating the motor MG1 at the target rotational speed Nm1 *. In Expression (2), “k1” in the second term on the right side is a gain of a proportional term. “K2” in the third term on the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (1)
Tm1 * = previous Tm1 * + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)

  When the target rotational speed Nm1 * and the torque command Tm1 * of the motor MG1 are thus calculated, the input / output limits Win and Wout of the battery 50 and the calculated torque command Tm1 * of the motor MG1 are multiplied by the current rotational speed Nm1 of the motor MG1. Torque limits Tmin and Tmax as upper and lower limits of the torque that may be output from the motor MG2 by dividing the deviation from the obtained power consumption (generated power) of the motor MG1 by the rotational speed Nm2 of the motor MG2 is expressed by the following equation (3). Further, the temporary motor torque Tm2tmp as the torque to be output from the motor MG2 is calculated by using the required torque Tr *, the torque command Tm1 *, and the gear ratio ρ of the power distribution and integration mechanism 30 (step S190). Calculated by equation (5) (step S200), with the calculated torque limits Tmin and Tmax Setting the torque command Tm2 * of the motor MG2 as a value obtained by limiting the motor torque Tm2tmp (step S210). By setting the torque command Tm2 * of the motor MG2 in this way, the required torque Tr * output to the ring gear shaft 32a as the drive shaft is set as a torque limited within the range of the input / output limits Win and Wout of the battery 50. can do. Equation (5) can be easily derived from the collinear diagram of FIG. 5 described above.

Tmin = (Win-Tm1 * ・ Nm1) / Nm2 (3)
Tmax = (Wout-Tm1 * ・ Nm1) / Nm2 (4)
Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (5)

  Thus, when the target engine speed Ne *, the target torque Te *, and the torque commands Tm1 *, Tm2 * of the motors MG1, MG2 are set, the target engine speed Ne * and the target torque Te * of the engine 22 are set in the engine ECU 24. The torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are transmitted to the motor ECU 40 (step S220), and the start time control routine is terminated. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * performs fuel injection control in the engine 22 such that the engine 22 is operated at an operating point indicated by the target rotational speed Ne * and the target torque Te *. Controls such as ignition control. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * controls the switching elements of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. To do. Thus, when the hydraulic pressures of the brake wheel cylinders 96a to 96d are sufficiently low, power based on the driver's drive request can be quickly output to the ring gear shaft 32a. Further, even when the hydraulic pressure of the brake wheel cylinders 96a to 96d is not sufficiently low, the waiting time tb elapses the time tref when the driving request by the driver is large or the vehicle may slide down on the slope. The power based on the driving request of the driver can be quickly output to the ring gear shaft 32a without waiting for the motor.

  On the other hand, the elapsed time tb has not passed the time tref, that is, the hydraulic pressure of the brake wheel cylinders 96a to 96d is not sufficiently low (step S110), and the accelerator opening Acc is smaller than the threshold value Accth. When the drive request is not large (step S120) and the gradient θ is smaller than the threshold θth and the vehicle does not slide down (step S130), it is necessary to quickly output the power based on the driver's drive request to the ring gear shaft 32a. As in step S140, the temporary required torque Trtmp is set based on the input accelerator opening Acc and the vehicle speed V using the required torque setting map illustrated in FIG. 3 (step S140). S150), a value obtained by subjecting the set temporary required torque Trtmp to the time constant τ and the following equation ( ), The calculated torque is set as the required torque Tr *, and the set required torque Tr * is multiplied by the rotation speed Nr of the ring gear shaft 32a, and the charge / discharge required power Pb * required by the battery 50 and the loss Loss. Is set as the required power Pe * required for the engine 22 (step S160). Here, the time constant τ is a time constant of the annealing process, and is determined in the range of value 0 to value 1. As described above, the required torque Tr * is obtained by subjecting the torque set by the driver based on the input accelerator opening Acc and the vehicle speed V to the torque required for the ring gear shaft 32a as the drive shaft. Therefore, the required power Pe * is set as less power than the power required by the driver for the ring gear shaft 32a as the drive shaft.

Tr * = τ ・ Previous Tr * + (1-τ) ・ Trtmp (6)

  Subsequently, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on the set required power Pe * (step S170), and the set target rotational speed Ne * and the rotational speed Nr of the ring gear shaft 32a are set. The target rotational speed Nm1 * of the motor MG1 is calculated using (Nm2 / Gr) and the gear ratio ρ of the power distribution and integration mechanism 30, and the motor MG1 is based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1. Torque command Tm1 * (step S180), torque limits Tmin and Tmax as upper and lower limits of torque that may be output from the motor MG2 are calculated (step S190), and the required torque Tr * and torque command Tm1 * are calculated. A temporary motor torque Tm2tmp as a torque to be output from the motor MG2 is calculated using the gear ratio ρ of the power distribution and integration mechanism 30. The torque command Tm2 * of the motor MG2 is set as a value obtained by limiting the temporary motor torque Tm2tmp with the calculated torque limits Tmin and Tmax (step S210), and the set target engine speed Ne * or The target torque Te * and torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the engine ECU 24 and the motor ECU 40, respectively (step S220), and the start time control routine is terminated. As described above, when the hydraulic pressure of the brake wheel cylinders 96a to 96d is not sufficiently low and it is not necessary to promptly output the power based on the driving request from the driver to the ring gear shaft 32a, the driver is driven to the ring gear shaft 32a. Power smaller than the power based on the demand can be output.

  FIG. 6 is an explanatory diagram showing an example of a time change between the hydraulic pressure of the brake wheel cylinder 96a and the power output from the ring gear shaft 32a. In the figure, the solid line shows the time change of the power when the power smaller than the power based on the driving request by the driver is output from the ring gear shaft 32a, and the broken line shows the power smaller than the power based on the driving request by the driver. The time change of the motive power when it outputs from 32a is shown. In the figure, time t0 is the time when the brake ECU 94 is instructed to release the brake. As shown in the figure, until the time t1 (= t0 + tref) elapses from time t0, that is, until the hydraulic pressure of the brake wheel cylinder 96a becomes sufficiently low, power smaller than the power required by the driver is output to the ring gear shaft 32a. To do. If it carries out like this, the drag of a brake can be suppressed and generation | occurrence | production of the noise by the drag of a brake can be suppressed. Further, after the time t1, the power requested by the driver can be quickly output to the ring gear shaft 32a.

  In the hybrid vehicle 20 of the embodiment described above, when the hydraulic pressure of the brake wheel cylinder 96a is sufficiently low and it is not necessary to output power to the ring gear shaft 32a quickly, the power required by the driver for the ring gear shaft 32a. Outputs less power. As a result, the generation of abnormal noise due to brake drag can be suppressed. Further, when the hydraulic pressure of the brake wheel cylinder 96a is sufficiently low or when it is necessary to quickly output power to the ring gear shaft 32a, the power requested by the driver can be quickly output to the ring gear shaft 32a. .

  In the hybrid vehicle 20 of the embodiment, the smoothed torque based on the driver's drive request is set as the required torque Tr * in the processes of steps S150 and S160. Since torque smaller than the torque based on the request may be set as the required torque Tr *, the torque based on the driver's drive request may be subjected to rate processing.

  In the hybrid vehicle 20 of the embodiment, even when the hydraulic pressure of the brake wheel cylinder 96a is not sufficiently low, the waiting time tb does not wait for the time tref to elapse when it is necessary to quickly output power to the ring gear shaft 32a. It is assumed that power based on the power requested by the driver is output. However, even in such a case, the driver requests until the waiting time tb elapses the time tref if the responsiveness can be lowered. A power smaller than the power may be output.

  In the hybrid vehicle 20 of the embodiment, the gradient θ from the gradient sensor 89 is taken into consideration, but the gradient θ may not be taken into consideration if a slight slip is allowed on a slope.

  In the hybrid vehicle 20 of the embodiment, the start-time control routine illustrated in FIG. 2 is executed by turning on and off the brake automatic continuation function switch 87 by the driver. The start time control routine shown in FIG.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is shifted by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. May be connected to an axle (an axle connected to the wheels 64a and 64b in FIG. 7) different from an axle to which the ring gear shaft 32a is connected (an axle to which the drive wheels 63a and 63b are connected).

  In the hybrid vehicle 20 of the embodiment, the power of the engine 22 is output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b via the power distribution and integration mechanism 30, but the modified example of FIG. The hybrid vehicle 220 includes an inner rotor 232 connected to the crankshaft 26 of the engine 22 and an outer rotor 234 connected to a drive shaft that outputs power to the drive wheels 63a and 63b. A counter-rotor motor 230 that transmits a part of the power to the drive shaft and converts the remaining power into electric power may be provided.

  The hybrid vehicle 20 of the embodiment is a so-called type in which a part of the power from the engine is transmitted to the axle side, and the remainder is converted into electric energy to charge a secondary battery or supply it to an electric motor attached to the axle side. Although it was configured as a parallel hybrid vehicle, it is configured as a so-called series hybrid vehicle that converts all of the power from the engine into electrical energy to charge the secondary battery and travels using the power from the secondary battery. Alternatively, it may be configured as a vehicle other than a hybrid vehicle, for example, a normal engine vehicle that travels only by power from the engine.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 according to an embodiment of the present invention. It is a flowchart which shows an example of the control routine at the time of start performed by the electronic control unit for hybrids 70 of an Example. It is explanatory drawing which shows an example of the map for torque setting. It is explanatory drawing which shows a mode that an example of the operating line of the engine 22, and target rotational speed Ne * and target torque Te * are set. FIG. 4 is an explanatory diagram showing an example of a collinear diagram for dynamically explaining rotational elements of a power distribution and integration mechanism 30; It is explanatory drawing which shows an example of the time change of the hydraulic pressure of the brake wheel cylinder 96a, and the motive power output from the ring gear shaft 32a. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example.

Explanation of symbols

20, 120, 220 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 24a CPU, 24b ROM, 24c RAM, 26 crankshaft, 28 damper, 30 power distribution integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 reduction gear, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51 temperature sensor, 52 battery electronic control Unit (battery ECU), 54 power line, 60 gear mechanism, 62 differential gear, 63a, 63b driving wheel, 64a, 64b wheel, 70 hybrid electronic control unit, 72 CPU, 74 ROM, 76 RAM, 0 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, 87 Brake automatic continuation function operation switch, 88 Vehicle speed sensor, 89 Gradient sensor, 90 Brake master cylinder, 92 brake actuator, 94 brake electronic control unit (brake ECU), 96a to 96d brake wheel cylinder, 230 rotor motor, 232 inner rotor 234 outer rotor, MG1, MG2 motor.

Claims (3)

A power source capable of outputting power to the axle,
A braking force that operates using a pressurized working fluid and applies a braking force to the axle based on a driver's braking request operation and can apply the braking force to the axle regardless of the driver's braking request operation. Granting means;
Drive request detection means for detecting a drive request by the driver;
A gradient detecting means for detecting a gradient in the longitudinal direction of the vehicle;
When a drive request by the driver is detected by the drive request detection means while the vehicle is stopped while a braking force is being applied to the axle by the braking force applying means in a state where no braking request operation has been performed by the driver The braking force applying means is controlled to start releasing the braking force applied by the braking force applying means, and the power source is controlled when the detected drive request is less than a predetermined request. The braking force applied by the braking force applying unit is a predetermined time period from when the release of the braking force applied by the power applying unit is started until the braking force applied by the braking force applying unit is sufficiently reduced. Less power than the power based on the detected drive request is output to the axle until the waiting time after the release of the application of After the predetermined waiting time has elapsed, control is performed so that power based on the detected drive request is output to the axle, and when the detected drive request is greater than or equal to the predetermined request, the wait time is Control is performed so that power based on the detected drive request is output to the axle without waiting for the predetermined time to elapse, and when the detected gradient is equal to or greater than a predetermined gradient, the detected drive request is Control means for controlling the power based on the detected drive request to be output to the axle without waiting for the waiting time to pass the predetermined time even if less than the predetermined request ;
Automobile equipped with. The automobile according to claim 1 ,
A switch operation detecting means for detecting an operation of a predetermined switch for turning on and off a function of maintaining a braking force applied to the axle even when the driver does not perform a braking request operation while the vehicle is stopped;
The control means provides the braking force applying means so that when the switch operation detecting means detects that the predetermined switch is turned on, a braking force is applied to the axle regardless of a driver's braking request operation. The vehicle that is the means to control. The automobile according to claim 1 or 2 , comprising at least one of an internal combustion engine and an electric motor as the power source.

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