JP7333201B2 - vehicle controller - Google Patents

Description

The present invention relates to a vehicle control device mounted on a hybrid vehicle.

Conventionally, as a vehicle control device, for example, as described in Japanese Unexamined Patent Application Publication No. 2000-213770, there is known a control device that is mounted on a hybrid vehicle that can be driven by an engine and a motor and that controls an inverter that drives the motor. ing. This control device attempts to obtain the deceleration torque requested by the driver by adjusting the strength of regenerative torque according to the release speed when the accelerator pedal is released.

JP-A-2000-213770

By the way, in this vehicle control device, when the engine is idling with the clutch engaged while the vehicle is stopped, the motor using the permanent magnet operates as a generator and a back electromotive force is applied to the inverter. For this reason, it is conceivable to perform a zero torque control that does not generate driving torque (positive torque) or braking torque (negative torque) in the motor.

However, in order to perform this zero torque control, battery power is consumed for the operation of the inverter and the motor.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a vehicle control apparatus capable of suppressing power consumption without generating a back electromotive force during idling.

That is, the vehicle control device according to the present invention is mounted on a vehicle that can be driven by an engine and a motor and that connects the engine and the motor via a clutch. an idling determination unit that determines whether the vehicle is idling, a rotation speed determination unit that determines whether the rotation speed of the motor is equal to or less than a preset rotation speed, and the idling determination unit and an operation control section that stops outputting a control signal to the inverter when the number of revolutions of the motor is determined to be equal to or less than a preset number of revolutions by the number of revolutions determining section. . According to this vehicle control device, the output of the control signal to the inverter is stopped when the vehicle is idling and the rotation speed of the motor is low. Thereby, power consumption for operating the inverter and the motor can be suppressed.

Further, in the vehicle control device according to the present invention, the operation control unit determines that the vehicle is idling by the idling determination unit, and the rotation speed determination unit determines that the rotation speed of the motor is not equal to or lower than a preset rotation speed. If it is determined that, a control signal may be output to the inverter. In this case, by outputting a control signal to the inverter when the vehicle is idling and the number of revolutions of the motor is not equal to or less than a preset number of revolutions, the inverter can be operated so as to suppress the back electromotive force. It becomes possible. Therefore, damage to the inverter can be suppressed.

Further, in the vehicle control device according to the present invention, the idling determination unit may determine that the vehicle is idling at least when the gear state of the transmission is in neutral.

According to the present invention, power consumption can be suppressed without generating a back electromotive voltage when the vehicle is idling.

1 is a block diagram showing a configuration outline of a vehicle control device according to an embodiment of the present invention; FIG. 2 is a circuit diagram showing electrical configurations of a battery, an inverter, and a motor in the vehicle control device of FIG. 1; FIG. 2 is a flow chart showing the operation of the vehicle control device of FIG. 1;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same or corresponding parts are denoted by the same reference numerals, and redundant explanations are omitted.

FIG. 1 is a block diagram showing a schematic configuration of a vehicle control device 1 according to this embodiment. As shown in FIG. 1, a vehicle control device 1 is mounted on a vehicle that can be driven by an engine 2 and a motor 4 and is connected to the engine 2 and the motor 4 via a clutch 3, and controls an inverter 6 that operates the motor 4. It is a device. The vehicle is, for example, a parallel hybrid vehicle, and is a large vehicle such as a bus or truck. An input shaft of the clutch 3 is connected to the output shaft of the engine 2 . A rotating shaft of a motor 4 is connected to the output shaft of the clutch 3 . The rotating shaft of the motor 4 is connected to the input shaft of the transmission 5 . A propeller shaft 11 is connected to the output shaft of the transmission 5 . Left and right drive wheels 14 are connected to the propeller shaft 11 via a differential mechanism 12 and a drive shaft 13 .

The engine 2 is an internal combustion engine such as a gasoline engine and a diesel engine. The clutch 3 mechanically connects and disconnects the engine 2 and the motor 4 . The motor 4 functions as an electric motor and a generator, and for example, a motor generator is used. Motor 4 operates upon receiving a control signal from inverter 6 . Inverter 6 is electrically connected to battery 7 and operates motor 4 using the power of battery 7 . The battery 7 is a rechargeable electric storage device that outputs a DC voltage. When the motor 4 functions as a drive power source, the inverter 6 converts the DC power of the battery 7 into AC power and supplies the AC power to the motor 4 . Details of the inverter 6 will be described later. The transmission 5 is a mechanism for transmitting the power of the engine 2 and the motor 4 to the drive wheels 14 by changing the torque, rotation speed, and rotation direction, and for example, an automatic transmission is used. The transmission 5 has a neutral gear stage so that the power input to the input shaft is not transmitted to the output side. The transmission 5 operates according to the operation of a shift operation section such as a shift lever, a shift switch, or a shift dial.

The vehicle control device 1 includes an ECU (Electronic Control Unit) 8 . The ECU 8 is an electronic control unit that controls the vehicle control device 1, and is mainly composed of a computer including a CPU [Central Processing Unit], ROM [Read Only Memory], and RAM [Random Access Memory]. The ECU 8 is electrically connected with the engine 2 , the clutch 3 , the motor 4 , the transmission 5 and the inverter 6 . For example, the ECU 8, the engine 2, the clutch 3, the motor 4, the transmission 5, and the inverter 6 may input and output data through CAN (Controller Area Network) communication.

The ECU 8 controls the operation of the inverter 6 based on the idling state of the vehicle and the rotation speed of the motor 4 . Further, the ECU 8 outputs control signals to the engine 2, the clutch 3, the transmission 5, and the inverter 6 according to the driving operation of the vehicle driver, the running state of the vehicle, etc., and performs drive control and regeneration control. good. Known control can be used for this drive control and regeneration control. For example, when the vehicle is driven only by the driving force of the motor 4 , the ECU 8 releases the connection of the clutch 3 and outputs a control signal to the inverter 6 . As a result, the motor 4 is driven to allow the vehicle to run. When the vehicle is driven by the driving force of the motor 4 and the engine 2 , the ECU 8 connects the clutch 3 and outputs control signals to the inverter 6 and the engine 2 . As a result, the motor 4 and the engine 2 are driven to allow the vehicle to run. Further, when performing regenerative control such as when running downhill, the ECU 8 releases the connection of the clutch 3 and causes the motor 4 to function as a generator to charge the battery 7 via the inverter 6 .

The ECU 8 inputs data such as the number of revolutions of the engine 2, the state of engagement of the clutch 3, the number of revolutions of the motor 4, and the gear state of the transmission 5 (gear position (gear stage) state). The ECU 8 is also connected to a plurality of sensors (not shown). For example, the ECU 8 is connected to an accelerator operation sensor such as an accelerator position sensor, a brake operation sensor, a shift lever position sensor, etc., and inputs vehicle driving operation data at any time, records them, and detects the state of accelerator operation and brake operation. state and the position of the shift lever.

The ECU 8 is provided with an idling determination section 81 . The idling determination unit 81 determines whether the vehicle is in an idling state. For example, the idling determination unit 81 determines whether the vehicle is in the idling state based on the gear position of the transmission 5 when the control state of the vehicle is not the running mode. Specifically, the idling determination unit 81 determines that the vehicle is in the idling state when the shift lever is in the neutral position. On the other hand, the idling determination unit 81 determines that the vehicle is not idling when the shift lever is not in the neutral position. The travel mode is a mode in which the vehicle travels by driving the engine 2 and the motor 4, and is called an HV mode, for example. In the traveling mode, when the accelerator is operated, the engine 2 and the motor 4 are driven according to the operation state, and the vehicle travels.

Further, the determination of whether or not the vehicle is in the idling state by the idling determination unit 81 may be performed as follows. That is, when the driving mode is in the off control state, the idling determination unit 81 determines that the position of the shift lever is neutral, the gear state of the transmission 5 is neutral, and the clutch 3 is engaged. If so, it may be determined that the vehicle is idling. On the other hand, the idling determination unit 81 determines that the position of the shift lever is not neutral, the gear state of the transmission 5 is not neutral, or the gear state of the transmission 5 is not neutral, or the clutch 3 is not in the connected state, it may be determined that the vehicle is not in the idling state. Further, another condition may be added as a condition for determining whether or not the engine is in the idling state in the idling determination unit 81 . Here, the idling state of the vehicle means a state in which the engine 2 and the motor 4 are operating in a no-load state.

The ECU 8 is provided with a rotational speed determination section 82 . The rotation speed determination unit 82 determines whether or not the rotation speed of the motor 4 is equal to or less than a preset rotation speed. The preset number of revolutions is the number of revolutions for determining that the vehicle is in the idling state, and is set in the ECU 8 as a number of revolutions greater than the number of revolutions in the idling state. For example, if the normal idling speed is 700 rpm, the preset speed is set to 1300 rpm. Further, the preset number of revolutions is not limited to 1300 rpm as long as the number of revolutions is within a range in which the back electromotive force of the motor 4 does not pose a problem. In other words, the preset number of revolutions may be set to a number of revolutions higher than the number of revolutions in the idling state and smaller than the number of revolutions at which the back electromotive force of the motor 4 becomes a problem. Specifically, the preset number of revolutions may be set to any number of revolutions from 900 to 2000 rpm.

The ECU 8 is provided with an operation control section 83 . The operation control section 83 controls the operation of the inverter 6 . That is, the operation control unit 83 stops outputting the control signal to the inverter 6 when the vehicle is idling and the rotation speed of the motor 4 is equal to or lower than the preset rotation speed. On the other hand, even when the vehicle is idling, the operation control unit 83 outputs a control signal to the inverter 6 to operate the inverter 6 when the rotation speed of the motor 4 is not equal to or lower than the preset rotation speed.

The idling determination unit 81, the rotation speed determination unit 82, and the operation control unit 83 are configured by, for example, introducing programs that perform the respective functions into the ECU 8. Also, the idling determination unit 81, the rotation speed determination unit 82, and the operation control unit 83 may be provided in the ECU 8 as physically separate control units. Further, the ECU 8 may be configured as a plurality of electronic control units for each individual control such as the operation control of the inverter 6 and the running control of the vehicle. Furthermore, in addition to the ECU 8, an electronic control unit that performs control other than the operation control of the inverter 6, such as running control of the vehicle, may be provided.

FIG. 2 is a circuit diagram showing electrical configurations of the battery 7, the inverter 6 and the motor 4. As shown in FIG. As shown in FIG. 2, as the motor 4, for example, a permanent magnet three-phase AC type motor generator is used. The motor 4 is rotationally driven by power supply from the inverter 6 . Also, the motor 4 generates power as its rotor rotates, and supplies power to the battery 7 via the inverter 6 .

The inverter 6 is composed of a bridge circuit having a plurality of switching elements 61 . For example, the inverter 6 is configured by connecting two switching elements 61 in series and providing three directly connected elements in parallel. This inverter 6 generates three-phase AC power by controlling on/off of six switching elements 61 . Each phase coil of the motor 4 is connected between the switching elements 61 connected in series. As the switching element 61, for example, a transistor is used, and more specifically, an insulated gate bipolar transistor (IGBT) is used. A diode 62 for freewheeling is connected between the emitter terminal and the collector terminal of the switching element 61 . The diode 62 is connected in the forward direction from the emitter terminal of the switching element 61 to the collector terminal.

The inverter 6 is operated by switching on and off of the switching element 61 by inputting a control signal to the gate terminal of the switching element 61 . When the control signal is not input to the gate terminal of the switching element 61, the switching element 61 of the inverter 6 is turned off. Therefore, since no current flows through the switching element 61, the power consumption of the battery 7 can be suppressed.

Next, the operation of the vehicle control device 1 according to this embodiment will be described.

FIG. 3 is a flow chart showing the operation of the vehicle control device 1. As shown in FIG. Each control process in FIG. 3 is executed by the ECU 8, for example.

First, as shown in step S10 in FIG. 3 (hereinafter simply referred to as "S10"; the same applies to the following steps), it is determined whether or not the vehicle is in the running mode. The driving mode is a control state in which the vehicle is driven by, for example, the engine 2 and the motor 4, and is called an HV mode, for example. When it is determined in S10 that the control state of the vehicle is the running mode, the control process proceeds to S20. In this case, the vehicle travels according to the driver's driving operation.

If it is determined in S10 that the control state of the vehicle is not in the running mode, it is determined whether or not the vehicle is idling (S12). For example, the idling determination unit 81 determines whether the vehicle is in an idling state based on the gear position of the transmission 5 . Specifically, the idling determination unit 81 determines that the vehicle is in the idling state when the shift lever is in the neutral position. On the other hand, the idling determination unit 81 determines that the vehicle is not idling when the shift lever is not in the neutral position.

Further, the idling determination unit 81 determines that the vehicle is in the idling state when the shift lever is in the neutral position, the gear stage of the transmission 5 is in the neutral state, and the clutch 3 is in the engaged state. It may be determined that there is On the other hand, if the shift lever position is not in neutral, the gear position of the transmission 5 is not in neutral, or the clutch 3 is not in the engaged state, the idling determination unit 81 determines that the vehicle is idling. It may be determined that it is not in the state.

Then, the control process proceeds to S14, and it is determined whether or not the number of revolutions of the motor 4 is equal to or less than a preset number of revolutions. That is, the rotation speed determination unit 82 determines whether or not the rotation speed of the motor 4 is equal to or less than a preset rotation speed.

If it is determined in S14 that the rotation speed of the motor 4 is not equal to or lower than the preset rotation speed, inverter operation control processing is performed (S16). The inverter operation control process is a process of outputting a control signal to the inverter 6 to operate the inverter 6 . For example, the operation control unit 83 outputs a control signal to the inverter 6 and executes zero torque control to set the output torque of the motor 4 to zero. This zero torque control suppresses damage to the inverter 6 due to the back electromotive force of the motor 4 .

More specifically, the rotation of the motor 4 generates a back electromotive force in the motor 4 . As the number of revolutions of the motor 4 increases, this back electromotive force also increases, and may exceed the withstand voltage of the components of the inverter 6 . Therefore, a control signal is output to the inverter 6 to operate the inverter 6, and the rotational state of the motor 4 is adjusted to perform zero torque control so that the torque of the motor 4 becomes zero. Thereby, the inverter 6 can be protected from the back electromotive force. However, operating the inverter 6 consumes the power of the battery 7 . Therefore, it is desirable to avoid operating the inverter 6 for a long time.

On the other hand, when it is determined in S14 that the rotation speed of the motor 4 is equal to or lower than the preset rotation speed, the output of the control signal to the inverter 6 is stopped (S18). That is, when the vehicle is idling and the rotation speed of the motor 4 is low, the operation control unit 83 stops outputting the control signal to the inverter 6 and turns off the switching element 61 . As a result, current does not flow through the switching element 61, and power consumption of the battery 7 is suppressed. Especially when the vehicle is in an idling state for a long time, it is effective in suppressing consumption of the battery 7 .

Then, the control process proceeds to S20, and it is determined whether or not the control end condition is satisfied. The case where the control end condition is met is, for example, the case where the power of the vehicle is turned off. If it is determined in S20 that the control end condition is not satisfied, the control process returns to S10, and the processes of S10 to S20 are executed as appropriate. At this time, in the previous control process, even if it was determined in S14 that the rotation speed of the motor 4 was equal to or lower than the preset rotation speed, and the output of the control signal to the inverter 6 was stopped in S18. When the number of revolutions of the motor 4 becomes less than the preset number of revolutions due to the driver's accelerator operation or the like, the inverter operation control process of S16 is executed. In other words, the inverter 6 can be appropriately protected from the back electromotive force by canceling the blocking of the switching element 61 and executing the zero torque control.

On the other hand, if it is determined in S20 that the control termination condition is satisfied, the series of control processing in FIG. 3 is terminated.

As described above, according to the vehicle control device 1 according to the present embodiment, when the vehicle is idling and the rotation speed of the motor 4 is low, outputting the control signal to the inverter 6 is stopped. Power consumption for operating the motor 4 can be suppressed.

Further, in the vehicle control device 1 according to the present embodiment, even when the vehicle is idling, when the number of revolutions of the motor 4 is high, a control signal is output to the inverter 6 to suppress the back electromotive force. It is possible to operate the inverter immediately. Therefore, damage to the inverter 6 can be suppressed. For example, when the number of revolutions of the motor 4 increases due to an accelerator operation or the like, the inverter 6 can be protected against the back electromotive force of the motor 4 by restoring the operation of the inverter 6 and performing zero torque control of the motor 4 . can.

Although the embodiment of the present invention has been described above, the above-described embodiment is a description of one embodiment of the vehicle control device according to the present invention, and the vehicle control device according to the present invention is described in the above embodiment. not limited to The vehicle control device according to the present invention may be a modification of the vehicle control device according to the above-described embodiment, or may be applied to another device within the scope of the claims.

DESCRIPTION OF SYMBOLS 1... Vehicle control apparatus, 2... Engine, 3... Clutch, 4... Motor, 5... Transmission, 6... Inverter, 7... Battery, 8... ECU, 61... Switching element, 62... Diode, 81... Idling determination part, 82... Rotation speed determination unit, 83... Operation control unit.

Claims (2)

In a vehicle control device that is mounted on a vehicle that can be driven by an engine and a motor and that connects the engine and the motor via a clutch and that controls an inverter that operates the motor,
an idling determination unit that determines whether or not the vehicle is idling when the control state of the vehicle is not in a driving mode in which the vehicle is driven by driving the engine and the motor;
a rotation speed determination unit that determines whether or not the rotation speed of the motor is equal to or lower than a preset rotation speed;
When the idling determination unit determines that the vehicle is idling and the rotation speed determination unit determines that the rotation speed of the motor is equal to or lower than a preset rotation speed, the control signal to the inverter is output. an operation control unit that stops output;
with
The idling determination unit determines that the vehicle is idling when the gear state of the transmission is in neutral and the clutch is in the engaged state.
Vehicle controller. When the idling determination unit determines that the vehicle is idling and the rotation speed determination unit determines that the rotation speed of the motor is not equal to or lower than a predetermined rotation speed, the operation control unit outputting control signals to the inverter,
The vehicle control device according to claim 1.

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