JP2019165523A - Discharge control system for vehicle and discharge control method for vehicle - Google Patents

Abstract

To discharge the electricity of smoothing capacitors of drive circuits so as to make a vehicle not to move when a front motor is directly connected to front wheels, and a rear motor is directly connected to rear wheels.SOLUTION: For example, when a vehicle moves after an electrical charge of a front smoothing capacitor C2 is discharged by a front motor 15, an electrical charge of a rear smoothing capacitor C3 is discharge-controlled by a rear motor 16 so that a vehicle drive force for suppressing the movement of a vehicle, that is, a backward drive force at the forward traveling of the vehicle, and a forward drive force at the backward traveling of the vehicle are generated by the rear motor 16. When the vehicle does not move, the electrical charge of the rear smoothing capacitor C3 is discharge-controlled by the rear motor 16 so that the vehicle drive force is not generated by the rear motor 16.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a vehicle discharge control system and a vehicle discharge control method, and more particularly, to a vehicle discharge control system and method for applying driving force to a front wheel and a rear wheel from a front motor and a rear motor, respectively.

  2. Description of the Related Art In recent years, electric vehicles that generate a driving force for driving a vehicle with a motor have become widespread. The electric vehicle includes a so-called electric vehicle (EV) in which only a motor is mounted as a vehicle drive source, a hybrid car in which an engine is mounted as a drive source, and a fuel cell vehicle in which a fuel cell is mounted. . In these electric vehicles, a driving battery is mounted, and electric power from the driving battery is converted into a power signal by a driving circuit such as an inverter and supplied (applied) to a motor. In general, a smoothing capacitor is provided between the drive circuit and the drive battery for stabilizing the power supplied from the drive battery. In addition, a drive motor mounted on this type of electric vehicle is often operated as a generator for storing power in a drive battery. In such a case, the motor is also referred to as a motor generator. Then, it is simply called a motor.

  A motor used as a vehicle drive source generally has a high voltage and large current characteristic. Therefore, a driving battery that supplies power to the motor also has a high voltage and large capacity characteristic. At the same time, the charge capacity accumulated in the smoothing capacitor is also low. large. For example, in a state where the vehicle is stopped, that is, in a state where the vehicle system is stopped (finished) as will be described later, the driving battery needs to be disconnected from the driving circuit of the driving motor, and at the same time, the smoothing capacitor It is also necessary to discharge the electric charge. Similarly, when the vehicle collides, the driving battery needs to be cut off, and at the same time, the charge of the smoothing capacitor needs to be discharged. Among these, the interruption of the driving battery is achieved, for example, by mechanically interrupting a switch or a relay interposed between the driving battery and the driving circuit, for example.

  Conventionally, as a vehicle discharge control system for discharging a charge of a smoothing capacitor at the time of termination of a vehicle system or a vehicle collision, for example, there is one described in Patent Document 1 below. In this vehicle discharge control system, for example, when two drive motors that individually apply driving force to each of the left and right wheels or the front and rear wheels of the vehicle are mounted, the electric charge of the smoothing capacitor of the drive circuit is discharged. The electric charge of the smoothing capacitor is discharged by each driving motor (motor coil) so that the driving force in the opposite direction is applied to the left and right wheels or the front and rear wheels of the vehicle.

International Publication Number WO2013 / 014768

  As described in Patent Document 1 described above, when the electric charge of the smoothing capacitor is discharged by the driving motor (motor coil), it is possible to control the driving motor not to generate the driving force (torque). is there. However, when considering a collision from the front or the rear of the vehicle, for example, when the smoothing capacitor discharge is discharged by the driving motor due to failure of the smoothing capacitor discharge system due to the collision or accumulation of errors, the driving motor is A driving force may be generated. That is, there is a possibility that the vehicle may move depending on the balance of the generated driving force. Thus, countermeasures are still insufficient when the driving motor generates an unintended vehicle driving force when discharging the smoothing capacitor. .

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle discharge control system and a vehicle discharge control method capable of discharging a smoothing capacitor while avoiding movement of the vehicle. There is to do.

In order to achieve the above object, a vehicle discharge control system according to claim 1,
A front motor that applies driving force to the front wheels, a rear motor that applies driving force to the rear wheels, a battery that supplies power to the front motor and the rear motor, and power from the battery is converted into a power signal to the front motor. A front drive circuit, a front smoothing capacitor provided between the front drive circuit and the battery, a rear drive circuit for converting power from the battery into a power signal to the rear motor, and the rear drive circuit, A rear smoothing capacitor provided between the battery, a vehicle state detection unit capable of detecting either or both of a vehicle system end and a vehicle collision, and a vehicle movement state detection for detecting the movement state of the vehicle. And a discharge control means for discharging the electric charge of the front smoothing capacitor and the rear smoothing capacitor. In,
The discharge control means is configured to charge the front smoothing capacitor or the rear smoothing capacitor with the front charge when at least one of a vehicle system end and a vehicle collision is detected by the vehicle state detection unit. A first discharge control unit that discharges by one of the motor and the rear motor; and after discharging by the first discharge control unit, and further confirming a vehicle movement state by the vehicle movement state detection unit, the front smoothing And a second discharge control section for discharging the charge of the other of the capacitor and the rear smoothing capacitor by the other of the front motor and the rear motor.

  According to this configuration, when the vehicle system ends or the vehicle collides, control is first performed to discharge the charge of either the front smoothing capacitor or the rear smoothing capacitor by either the front motor or the rear motor. Once the vehicle movement state is detected. Therefore, it is possible to accurately prevent the vehicle from moving at the time of discharge in a situation in which the discharge is performed almost simultaneously at the rear and the front as in the past, for example, in the situation where the vehicle system ends or the vehicle collides. It can be avoided.

  That is, the discharge by each motor can generally be selected in various ways, such as a discharge that generates a forward / reverse driving force in the vehicle or a discharge that does not generate a driving force. After confirming the above, it is possible to discharge one of the front smoothing capacitor and the rear smoothing capacitor appropriately.

  The vehicle discharge control system according to claim 2 is the vehicle discharge control system according to claim 1, wherein the second discharge control unit of the discharge control means is a vehicle by at least one of the front motor and the rear motor. The discharge control that does not generate a driving force is possible, and when the vehicle movement state detection unit detects that the vehicle is not moving after the discharge by one of the front motor and the rear motor, the front motor and It is characterized in that the charge of either the front smoothing capacitor or the rear smoothing capacitor is discharged so that no driving force is generated in either of the rear motors.

  According to this configuration, even if the discharge is performed by either the front motor or the rear motor, after confirming that the vehicle is not moving, the discharge is performed by either the front motor or the rear motor. Accurate discharge of the other one of the front smoothing capacitor and the rear smoothing capacitor is possible so that the driving force is not generated by either the motor or the rear motor. Therefore, the smoothing capacitor can be discharged while reliably preventing the movement of the vehicle.

  A vehicle discharge control system according to a third aspect is the vehicle discharge control system according to the first aspect, wherein the second discharge control unit of the discharge control means is positive by at least one of the front motor and the rear motor. The discharge control for generating the reverse vehicle driving force and the discharge control for not generating the vehicle driving force by one of the front motor and the rear motor can be selected, and the discharge by one of the front motor and the rear motor is possible. After that, when the vehicle movement state detection unit detects that the vehicle is moving, the front smoothing capacitor and the rear are arranged so that a vehicle driving force is generated in the direction of moving the vehicle in the direction opposite to the movement direction of the vehicle. It is characterized by discharging the other charge of the smoothing capacitor.

  According to this configuration, when it is detected that any one of the front motor and the rear motor is caused to move by the discharge of either the front smoothing capacitor or the rear smoothing capacitor, any of the front motor and the rear motor is detected. The discharge of either the front smoothing capacitor or the rear smoothing capacitor by the other is performed so as to generate a driving force that moves in the direction opposite to the movement of the vehicle. Therefore, the movement of the vehicle due to the discharge of either the front or the rear can be suppressed by the discharge of the other of the front or the rear, and the discharge of the smoothing capacitor of the front or rear is made safer without movement. be able to.

  The vehicle discharge control system according to claim 4 is the vehicle discharge control system according to any one of claims 1 to 3, wherein the vehicle movement state detection means is the other of the front motor and the rear motor. The movement of the vehicle is detected based on a detection signal of a motor resolver provided in the vehicle.

  According to this configuration, it is possible to increase the cost and structure by detecting the movement of the vehicle using the detection signal of the motor resolver that is generally provided for rotation control of either the front motor or the rear motor. Accordingly, the movement of the vehicle can be detected as quickly and accurately as possible, and the smoothing capacitor can be discharged without causing the movement of the vehicle more accurately.

  The vehicle discharge control system according to claim 5 is the vehicle discharge system according to any one of claims 1 to 4, wherein the first discharge control unit uses the front motor to charge the front smoothing capacitor. And the second discharge controller discharges the electric charge of the rear smoothing capacitor by the rear motor.

  According to this configuration, even when there is an abnormality in the front smoothing capacitor due to a collision from the front of the vehicle, it is possible to reliably prevent the movement of the vehicle.

The vehicle discharge control method according to claim 6 includes a front motor that applies a driving force to a front wheel, a rear motor that applies a driving force to a rear wheel, a battery that supplies electric power to the front motor and the rear motor, and the battery. A front drive circuit that converts power from the power signal to the front motor, a front smoothing capacitor provided between the front drive circuit and the battery, and a power signal from the battery to the rear motor A rear drive circuit for converting to a rear drive circuit, a rear smoothing capacitor provided between the rear drive circuit and the battery, a vehicle state detection unit capable of detecting either or both of a vehicle system end and a vehicle collision; A vehicle movement state detection unit for detecting the movement state of the vehicle, and a discharge control for discharging electric charges of the front smoothing capacitor and the rear smoothing capacitor. The vehicular discharge control method and means, and
The discharge control means is configured to charge the front smoothing capacitor or the rear smoothing capacitor with the front charge when at least one of a vehicle system end and a vehicle collision is detected by the vehicle state detection unit. After discharging by either one of the motor or the rear motor and discharging by either one of the front motor or the rear motor, after confirming the vehicle movement state by the vehicle movement state detector, the front smoothing capacitor and the rear motor The other charge of the smoothing capacitor is discharged by the other of the front motor and the rear motor.

  According to this configuration, when the vehicle system ends or the vehicle collides, control is first performed to discharge the charge of either the front smoothing capacitor or the rear smoothing capacitor by either the front motor or the rear motor. Once the vehicle movement state is detected. Therefore, it is possible to accurately prevent the vehicle from moving at the time of discharge in a situation in which the discharge is performed almost simultaneously at the rear and the front as in the past, for example, in the situation where the vehicle system ends or the vehicle collides. It can be avoided.

  That is, the discharge by each motor can generally be selected in various ways, such as a discharge that generates a forward / reverse driving force in the vehicle or a discharge that does not generate a driving force. After confirming the above, it is possible to discharge one of the front smoothing capacitor and the rear smoothing capacitor appropriately.

  As described above, according to the present invention, first, after the electric charge of either the front smoothing capacitor or the rear smoothing capacitor is discharged by either the front motor or the rear motor, the movement of the vehicle is detected, It becomes possible to discharge the electric charge of either the front smoothing capacitor or the rear smoothing capacitor by either one of the front motor and the rear motor accurately, and the discharge using the motor can be performed accurately while avoiding the movement of the vehicle. It is possible to prevent unnecessary movement of the vehicle at the end of the vehicle system or at the time of collision and improve safety.

1 is a schematic plan view showing an embodiment of a vehicle to which a vehicle discharge control system of the present invention is applied. It is a block diagram which shows the power control unit and motor drive system of FIG. It is a flowchart which shows the arithmetic processing performed with the power control apparatus of FIG. It is explanatory drawing of the effect | action by the arithmetic processing of FIG.

  Hereinafter, an embodiment of a hybrid vehicle to which a vehicle discharge control system of the present invention is applied will be described in detail with reference to the drawings. FIG. 1 is a schematic plan view of the hybrid vehicle of this embodiment. This vehicle is, for example, a station wagon type passenger vehicle. An engine 12 as one of the drive sources of the vehicle is disposed in an engine room in front of the vehicle, and a transmission 14 is connected to the rear of the engine 12 in the vehicle. In this embodiment, a front motor 15 for applying a driving force to the front wheels 10FL and 10FR is interposed between the engine 12 and the transmission 14. The front motor 15 is composed of, for example, a three-phase AC motor, and is operated as a generator for accumulating in a driving battery 24 described later, as in an existing hybrid vehicle. It is called a motor.

  In this embodiment, a front differential (front differential gear) 18 is built in the transmission 14, and the drive force of the engine 12 alone or the drive force of the front motor 15 alone via the transmission 14 and the front differential 18, Alternatively, the combined driving force of the engine 12 and the front motor 15 is applied to the front wheels 10FL and 10FR. The operating state of the front motor 15 is cooperatively controlled with the operating state of the engine 12 by a power control unit 33 described later, similarly to the well-known hybrid control. It should be noted that the arrangement of the front motor 15 is not limited to the above, and may be installed inside the transmission 14, for example. Further, the front motor 15 of this embodiment is directly connected to the front wheels 10FL and 10FR.

  In this embodiment, a rear differential (rear differential gear) 22 is interposed between the rear left and right wheels 10RL, 10RR, and a rear motor for applying a driving force to the rear wheels 10RL, 10RR. 16 is connected. Accordingly, the driving force of the rear motor 16 is applied to the rear wheels 10RL and 10RR via the rear differential 22. Like the existing hybrid vehicle, the rear motor 16 is also operated as a generator (generator) for storing power in the driving battery 24, but is simply referred to as a rear motor here. Further, the operation state of the rear motor 16 is cooperatively controlled by the power control unit 33 described later in cooperation with the operation states of the engine 12 and the front motor 15 in the same manner as the well-known hybrid control. Further, the rear motor 16 of this embodiment is constituted by, for example, a three-phase AC motor, and is directly connected to the rear wheels 10RL and 10RR.

  This vehicle is equipped with a driving battery 24 that supplies power to the front motor 15 and the rear motor 16. As described above, both the front motor 15 that applies driving force to the front wheels 10FL and 10FR and the rear motor 16 that applies driving force to the rear wheels 10RL and 10RR have high voltage and large current characteristics in order to generate vehicle driving force. is there. Accordingly, the driving battery 24 that supplies power to the front motor 15 and the rear motor 16 also has a high voltage and a large capacity. Therefore, the operating state of the driving battery 24, that is, the charge / discharge state, is controlled separately from the so-called 12V battery (auxiliary battery) by the power control unit 33 described later.

  Further, this vehicle is provided with a start switch 30 that permits the operation of the vehicle, for example, on an instrument panel. The start switch 30 permits the operation of the engine 12 by an ON operation and permits the start of operation as a vehicle. The start switch 30 corresponds to an ignition switch for a vehicle equipped with only the engine as a drive source. However, in a hybrid vehicle, the engine is often stopped when the vehicle is stopped. Twelve operations are permitted. In the vehicle of this embodiment, when the start switch 30 is turned on, various control units 31 to 34 described later are started, various controls are started, and when the start switch 30 is turned off, the control units 31-34 also stops operation | movement and control is also complete | finished. In the vehicle of this embodiment, it is considered that the vehicle system is activated by these controls. Therefore, the on operation of the start switch 30 starts the vehicle system, and the off operation of the start switch 30 ends the vehicle system.

  In this vehicle, as in recent vehicles, the engine 12 is driven by the engine control unit 31, the transmission 14 is driven by the transmission control unit 32, and the front motor 15, the rear motor 16 and the driving battery 24 are driven by the power control unit 33, respectively. Be controlled. The vehicle is also equipped with an airbag device as a vehicle collision detection means. The airbag device includes, for example, an acceleration sensor 36 provided on a front bumper of a vehicle and a sensor signal of the acceleration sensor 36 together with a well-known driver's seat airbag and passenger seat airbag (not shown). And an airbag control unit 34 for controlling the operating state of the inflator for deploying the inflator.

  These control units 31 to 34 are configured by mounting an arithmetic processing device such as a microcomputer and have an advanced arithmetic processing function. Therefore, these control units 31 to 34 are configured to include an input / output unit, a storage unit, and the like in addition to the arithmetic processing unit, similarly to the computer system. Further, like the recent vehicles, the control units 31 to 34 are configured to communicate with each other, perform coordinated control with each other, and exchange and share information. In addition, as described above, these control units 31 to 34 are activated when the start switch 30 is turned on and stopped when the start switch 30 is turned off.

  FIG. 2 is a configuration diagram showing the power control unit 33 and the motor drive system of FIG. As described above, the power control unit 33 includes a power control device 33a that performs arithmetic processing, an input / output unit 33b, and a storage unit 33c. The motor drive system includes a drive battery control unit 41 that controls the charge / discharge state of the drive battery 24, a front motor control unit 42 that controls the operating state of the front motor 15, separately from the power control unit 33. A rear motor control unit 43 that controls the operating state of the rear motor 16 is provided, which is housed in a separate housing from the power control unit 33. Specifically, the drive battery control unit 41 is disposed in the immediate vicinity of the drive battery 24, the front motor control unit 42 is disposed in the immediate vicinity of the front motor 15, and the rear motor control unit 43 is disposed in the immediate vicinity of the rear motor 16. It is installed. The driving battery control unit 41, the front motor control unit 42, and the rear motor control unit 43 are all equivalent to the battery control unit and the motor control unit in the existing hybrid vehicle, and therefore the configuration will be briefly described. .

  The drive battery control unit 41 includes a main relay 41a for simultaneously opening and closing both poles of the drive battery 24, and a converter for boosting the power of the drive battery 24 and reducing the power generation of the front motor 15 and the rear motor 16. 41b, a battery C1 for smoothing power between the driving battery 24 and the converter 41b, and a driving battery control device 41c for controlling the operating state of the main relay 41a and the converter 41b. The converter 41b connects power elements P1 and P2 including a switching element and a diode connected in reverse parallel thereto in series, and a reactor L is interposed between the connection point and the positive electrode of the driving battery 24, for example. Configured. Both ends of the series connection of the power elements P1, P2 are connected as input / output ends of the converter 41b to a front motor inverter 42a of the front motor control unit 42 and a rear motor inverter 43a of the rear motor control unit 43 which will be described later.

  The front motor control unit 42 is connected to the input / output terminal of the converter 41b and is connected to the lower arm and upper arm of the U-phase, V-phase, and W-phase motor coils 15a of the three-phase AC motor constituting the front motor 15. A front motor inverter 42a provided with P3 to P8, a front smoothing capacitor C2 interposed between the front motor inverter 42a and the converter 41b, and a front inverter control device 42b for controlling the operating state of the front motor inverter 42a It is prepared for. The rear motor control unit 43 is connected to the input / output terminal of the converter 41b and is connected to the lower arm and upper arm of the U-phase, V-phase, and W-phase motor coils 16a of the three-phase AC motor constituting the rear motor 16. A rear motor inverter 43a provided with P9 to P14, a rear smoothing capacitor C3 interposed between the rear motor inverter 43a and the converter 41b, and a rear inverter control device 43c for controlling the operating state of the rear motor inverter 43a. It is prepared for.

  The drive battery control device 41c, the front inverter control device 42b, and the rear inverter control device 43c all control the operating states of the converter 41b, the front inverter, and the rear inverter, respectively, in accordance with a control command from the power control unit 33. It is configured as follows. Further, the front motor 15 is provided with a front motor resolver 26 that precisely and quickly detects the rotational state of the front motor 15, and an output signal thereof is input to the front inverter control device 42b. Further, the rear motor 16 is provided with a rear motor resolver 28 that precisely and quickly detects the rotation state of the rear motor 16, and an output signal thereof is input to the rear inverter control device 43c. As is well known, these motor resolvers are provided with, for example, a plurality of coils around a rotor, supply an AC reference signal to one of the coils, and another stator when the rotor coil rotates. The rotational state of the motor is precisely and rapidly detected from the phase of the output signal of the side coil.

  In the power control unit 33, the operating state of the engine 12, the driving battery 24, the front motor 15, the rear motor 16, or the transmission 14 is determined according to the state of the vehicle and the operation / input state by the driver, as in the known hybrid control. Overall control. Specifically, those control commands (control command values) are calculated and set and output to the corresponding control unit or control device. The power control unit 33 also controls to start (activate) all the systems of the vehicle when the start switch 30 is turned on or to end all the systems of the vehicle when the start switch 30 is turned off. Control. In addition, even if all the systems of the vehicle are finished, the function of the vehicle is not completely stopped. For example, power supply for holding the storage contents of the volatile memory is continuously performed.

  Next, the charge discharge control of the front smoothing capacitor C2 and the rear smoothing capacitor C3 performed by the power control unit 33 will be described. FIG. 3 is a flowchart showing a calculation process for the capacitor charge discharge control. This calculation process is executed by, for example, a timer interruption process with a predetermined sampling period set in advance. First, in step S1, it is determined whether or not the start switch 30 is turned off, and the start switch 30 is turned off. That is, when the system of the vehicle is finished, the process proceeds to step S3. Otherwise, the process proceeds to step S2.

  In step S2, as described above, for example, it is determined whether or not there is vehicle collision information through mutual communication with the airbag control unit. If there is vehicle collision information, that is, if the vehicle collides, step S2 is performed. The process proceeds to S3, and otherwise returns.

  In step S3, charge discharge control of the front smoothing capacitor C2 by the front motor 15 (motor coil 15a) is performed according to individual calculation processing (not shown). In this embodiment, the electric charge of the front smoothing capacitor C2 is discharged by the motor coil 15a of the front motor 15 so that the front motor 15 does not generate a driving force (torque) in the forward or backward direction of the vehicle. Control for discharging the electric charge of the smoothing capacitor with the motor coil so that the motor does not generate driving force is also described in, for example, Patent Document 1 described above.

  Next, the process proceeds to step S4, and the output signal of the rear motor resolver 28 is read from, for example, the aforementioned rear inverter control device 43c.

  Next, the process proceeds to step S5, where it is determined whether or not the vehicle moves from the output signal of the rear motor resolver 28 read in step S4. If the vehicle moves, the process proceeds to step S6. Proceeds to step S9.

  In step S6, it is determined from the output signal of the rear motor resolver 28 read in step S4 whether or not the movement (movement) of the vehicle is forward. If the movement (movement) of the vehicle is forward, the process proceeds to step S7. If not, that is, if the movement (movement) of the vehicle is reverse, the process proceeds to step S8.

  In step S7, in accordance with individual calculation processing (not shown), control is performed to discharge the electric charge of the rear smoothing capacitor C3 by the rear motor 16 (motor coil 16a) so that the rear motor 16 generates a backward driving force (torque). To do. The method of discharging the electric charge of the rear smoothing capacitor C3 by the motor coil 16a of the rear motor 16 so that the rear motor 16 generates the reverse drive force (torque) is, for example, a well-known hybrid rear that generates the reverse drive force (torque) by the rear motor 16. Equivalent to motor control.

  In step S8, the rear motor 16 (motor coil 16a) is controlled to discharge the electric charge of the rear smoothing capacitor C3 so that the vehicle driving force (torque) is generated by the rear motor 16 according to an individual calculation process (not shown). Return from. A method of discharging the electric charge of the rear smoothing capacitor C3 by the motor coil 16a of the rear motor 16 so that the rear motor 16 generates forward driving force (torque) is, for example, a well-known hybrid rear that generates forward driving force (torque) by the rear motor 16. Equivalent to motor control.

  In step S9, control is performed so that the electric charge of the rear smoothing capacitor C3 is discharged by the rear motor 16 (motor coil 16a) so that the vehicle driving force (torque) is not generated by the rear motor 16. Control for discharging the electric charge of the rear smoothing capacitor C3 by the motor coil 16a of the rear motor 16 so that the rear motor 16 does not generate vehicle driving force (torque) is equivalent to that described in Patent Document 1 described above.

  The forward driving force or the backward driving force generated by the rear motor 16 when the electric charge of the rear smoothing capacitor C3 is discharged by the rear motor 16 (motor coil 16a) is controlled, for example, by the amount of charge accumulated in the front smoothing capacitor C2 in advance. Since the driving force (torque) generated by the front motor 15 generated by the discharge can be calculated approximately, the driving force (torque) that cancels the driving force (torque) generated by the front motor 15 is generated by the rear motor 16. Thus, the charge discharge of the rear smoothing capacitor C3 may be controlled.

  According to this calculation process, when a vehicle system end or a vehicle collision is detected (vehicle state detection unit), first, the electric charge of the front smoothing capacitor C2 is discharged by the motor coil 15a of the front motor 15 (first discharge). Control unit). As is well known, there is a method in which the electric charge of the smoothing capacitor is discharged by an element of the drive circuit, but this discharge control takes a long time to discharge. On the other hand, if the electric charge of the smoothing capacitor is discharged with a motor coil having high voltage and large current characteristics, the required discharge time may be small. Accordingly, the electric charge of the front smoothing capacitor C2 is quickly discharged by the motor coil 15a of the front motor 15.

  In this embodiment, when the front smoothing capacitor C2 is discharged, the operating state of the front motor inverter 42a is controlled so that the front motor 15 does not generate vehicle driving force. However, as described above, particularly when a vehicle collides, the front motor 15 may generate an unintended vehicle driving force as a result of a failure of the discharge system of the front smoothing capacitor C2 or accumulation of errors. . In this embodiment, the movement of the vehicle due to an unintended vehicle driving force that may be generated by the front motor 15 is detected from the rotation state of the rear motor 16, more precisely from the output signal of the rear motor resolver 28 (vehicle movement). State detector). As described above, since the motor resolver can accurately and rapidly detect the rotation state of the motor, the movement of the vehicle from the output signal of the rear motor resolver 28, and whether it is forward or backward, It can be detected accurately.

  As a result of discharging the electric charge of the front smoothing capacitor C2 by the front motor 15 as described above, when the vehicle moves forward, as shown in FIG. 4, the rear smoothing capacitor C3 is generated so that the rear motor 16 generates a backward driving force. Is discharged by the motor coil 16 a of the rear motor 16. As a result of discharging the electric charge of the front smoothing capacitor C2 by the front motor 15, when the vehicle moves backward, the electric charge of the rear smoothing capacitor C3 is generated by the motor coil 16a of the rear motor 16 so that the forward driving force is generated by the rear motor 16. Discharge. Further, when the vehicle does not move as a result of discharging the electric charge of the front smoothing capacitor C2 by the front motor 15, the electric charge of the rear smoothing capacitor C3 is transferred by the motor coil 16a of the rear motor 16 so that the vehicle driving force is not generated by the rear motor 16. Discharge (the second discharge control unit).

  Thus, in the vehicle discharge control system of this embodiment, when the vehicle moves as a result of discharging the electric charge of the front smoothing capacitor C2 by the front motor 15 (motor coil 15a), the movement of the vehicle is suppressed. The rear motor 16 (motor coil 16a) charges the rear smoothing capacitor C3 so that the vehicle driving force, that is, the backward driving force when the vehicle moves forward, and the forward driving force when the vehicle moves backward are generated by the rear motor 16, respectively. Discharge control. When the vehicle does not move, the electric charge of the rear smoothing capacitor C3 is controlled to be discharged by the rear motor 16 (motor coil 16a) so that the vehicle driving force is not generated by the rear motor 16. As a result, in any case, it is possible to suppress the vehicle from moving when the smoothing capacitor of the motor drive circuit is discharged.

  In addition, the movement of the vehicle is precisely and quickly detected by the rear motor resolver 28 provided in the rear motor 16, so that the movement of the vehicle is detected as quickly and accurately as possible without an increase in cost and structure. can do.

  In the above-described embodiment, the description has been given of the hybrid vehicle including the motor and the drive circuit that individually apply the driving force to the front wheels and the rear wheels, but the present invention applies the driving force to the front wheels and the rear wheels individually. As long as it is an electric vehicle provided with a motor and a driving circuit, it can be applied to any vehicle. Examples of such an electric vehicle include an electric vehicle and a fuel cell vehicle.

  In the above embodiment, only one front motor for driving the front left and right wheels and only one rear motor for driving the rear left and right wheels are described in detail. Two front motors for individually driving the front left and right wheels may be provided, or two rear motors for individually driving the rear left and right wheels may be provided.

  In the above embodiment, only the electric vehicle provided with only one battery (drive battery) for supplying power to the front motor and the rear motor has been described in detail. For example, to supply power to the front motor. Two batteries for supplying power to the battery and the rear motor may be provided. Furthermore, as described above, when two front motors and two rear motors are provided, batteries for supplying power independently to the respective motors may be provided.

  Further, the vehicle system end may be a conventional ignition switch OFF operation instead of the start switch OFF operation, or a completely individual system end input means may be provided.

  Further, the front motor in the above embodiment can be divided into a front motor that applies driving force to the front wheels and a front generator that generates electric power from the rotation of the front wheels, and each can be powered and regenerated by individual inverters.

  Further, the smoothing capacitor charge discharge control of the present invention can be similarly applied to, for example, discarding a vehicle.

  Further, in the above embodiment, only the case where the charge of the front smoothing capacitor is discharged by the front motor and then the charge of the rear smoothing capacitor is discharged by the rear motor has been described in detail. For example, the charge of the rear smoothing capacitor may be discharged by the rear motor, and then the charge of the front smoothing capacitor may be discharged by the front motor. Furthermore, after the front smoothing capacitor is discharged by the rear motor, the rear smoothing capacitor is discharged by the front motor, or after the rear smoothing capacitor is discharged by the front motor, the front smoothing capacitor is discharged by the rear motor. Or can be discharged. These cases can be dealt with, for example, by simply changing and setting “front” and “rear” in the flowchart of FIG. 3 and the above description according to the corresponding control mode.

  It goes without saying that the present invention includes various embodiments not described above. Therefore, the technical scope of the present invention is defined only by the invention-specifying matters described in the scope of claims which is appropriate from the above description.

10FL to 10RR Wheel 12 Engine 15 Front motor 16 Rear motor 24 Battery for driving (battery)
26 Front motor resolver 28 Rear motor resolver 33 Power control unit 42a Front motor inverter (drive circuit)
43a Rear motor inverter (drive circuit)
C2 Front smoothing capacitor C3 Rear smoothing capacitor

Claims (6)

A front motor that applies driving force to the front wheels, a rear motor that applies driving force to the rear wheels, a battery that supplies power to the front motor and the rear motor, and power from the battery is converted into a power signal to the front motor. A front drive circuit, a front smoothing capacitor provided between the front drive circuit and the battery, a rear drive circuit for converting power from the battery into a power signal to the rear motor, and the rear drive circuit, A rear smoothing capacitor provided between the battery, a vehicle state detection unit capable of detecting either or both of a vehicle system end and a vehicle collision, and a vehicle movement state detection for detecting the movement state of the vehicle. And a discharge control means for discharging the electric charge of the front smoothing capacitor and the rear smoothing capacitor. In,
The discharge control means includes
When at least one of a vehicle system end and a vehicle collision is detected by the vehicle state detection unit,
A first discharge control unit that discharges one of the front smoothing capacitor and the rear smoothing capacitor by one of the front motor and the rear motor;
After discharging by the first discharge control unit, and further confirming the vehicle movement state by the vehicle movement state detection unit, the charge of either the front smoothing capacitor or the rear smoothing capacitor is charged to the front motor and rear motor. A second discharge control section for discharging by either one of
A vehicle discharge control system comprising: The second discharge controller of the discharge controller is
The discharge control that does not generate vehicle driving force by at least one of the front motor and the rear motor is possible,
After the discharge by one of the front motor and the rear motor, when the vehicle movement state detection unit detects that the vehicle is not moving, the driving force is not generated in either the front motor or the rear motor. 2. The vehicle discharge control system according to claim 1, wherein the electric charge of one of the front smoothing capacitor and the rear smoothing capacitor is discharged. The second discharge controller of the discharge controller is
It is possible to select at least the discharge control for generating forward / reverse vehicle driving force by either one of the front motor or the rear motor and the discharge control for not generating vehicle driving force by either the front motor or the rear motor. ,
After the discharge by one of the front motor and the rear motor, when the vehicle movement state detection unit detects that the vehicle is moving, the vehicle driving force in the direction of moving the vehicle in the direction opposite to the movement direction of the vehicle is 2. The vehicle discharge control system according to claim 1, wherein one of the front smoothing capacitor and the rear smoothing capacitor is discharged so as to be generated.   4. The vehicle movement state detection means detects the movement of the vehicle based on a detection signal of a motor resolver provided on one of the front motor and the rear motor. The vehicle discharge control system described in 1. The first discharge controller discharges the electric charge of the front smoothing capacitor by the front motor,
The vehicle discharge control system according to any one of claims 1 to 4, wherein the second discharge control unit discharges the electric charge of the rear smoothing capacitor by the rear motor. A front motor that applies driving force to the front wheels, a rear motor that applies driving force to the rear wheels, a battery that supplies power to the front motor and the rear motor, and power from the battery is converted into a power signal to the front motor. A front drive circuit, a front smoothing capacitor provided between the front drive circuit and the battery, a rear drive circuit for converting power from the battery into a power signal to the rear motor, and the rear drive circuit, A rear smoothing capacitor provided between the battery, a vehicle state detection unit capable of detecting either or both of a vehicle system end and a vehicle collision, and a vehicle movement state detection for detecting the movement state of the vehicle. And a discharge control means for discharging the electric charge of the front smoothing capacitor and the rear smoothing capacitor. Stomach,
The discharge control means includes
When at least one of a vehicle system end and a vehicle collision is detected by the vehicle state detection unit, the charge of either the front smoothing capacitor or the rear smoothing capacitor is charged to either the front motor or the rear motor. Discharged by one side,
After discharging by one of the front motor and the rear motor, and further confirming the vehicle movement state by the vehicle movement state detector, the charge of the other of the front smoothing capacitor and the rear smoothing capacitor is charged to the front A vehicle discharge control method, wherein discharge is performed by either the motor or the rear motor.

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