JP7367601B2 - Vehicle control device, program - Google Patents

Description

The present invention includes a power storage device, an inverter electrically connected to the power storage device, a stator winding electrically connected to the inverter, and a rotating electric machine having a rotor capable of transmitting power to a drive wheel. The present invention relates to a vehicle control device and a program applied to a vehicle equipped with the vehicle.

As seen in Patent Document 1, this type of control device determines that the shift position is neutral and that the rotational speed of the rotor of a permanent magnet rotating electric machine is lower than a predetermined field weakening rotational speed. There is a known device that stops switching control of the inverter when it is determined that the inverter is low. This suppresses the back electromotive force generated when the rotating electric machine functions as a generator.

Patent No. 3077434

By the way, as a control device, it is possible to reduce the power consumption of the inverter by stopping the switching control of the inverter. At this time, it is also conceivable to set a condition that the shift position is neutral as described in Patent Document 1 as a condition for stopping the switching control.

Here, while the shift position is in the drive range, the vehicle may repeatedly start and stop due to the driver's accelerator and brake operations. In this case, if the condition for stopping the switching control is that the shift position is neutral, it may become impossible to stop the switching control even though the switching control can be stopped. For this reason, there is still room for improvement in the technology for reducing the power consumption of the inverter by stopping switching control.

A main object of the present invention is to provide a vehicle control device and program that can reduce power consumption of an inverter.

A first invention includes a power storage device;
an inverter electrically connected to the power storage device;
A vehicle control device applied to a vehicle including a stator winding electrically connected to the inverter, and a rotating electric machine having a rotor capable of transmitting power to a drive wheel,
a speed acquisition unit that acquires information regarding the traveling speed of the vehicle;
a driving force determination unit that determines whether the driver of the vehicle has an intention to generate a driving force for the vehicle by controlling the drive of the rotating electrical machine, based on the information acquired by the speed acquisition unit;
and a stop unit that stops switching control of the inverter on the condition that the driving force determining unit determines that there is no intention.

In the first invention, based on the information acquired by the speed acquisition section, it is determined whether the driver of the vehicle has an intention to generate driving force for the vehicle by controlling the drive of the rotating electric machine. Then, on condition that it is determined that the driver has the above-mentioned intention, the switching control of the inverter is stopped. Thereby, it is possible to reduce power consumption of the inverter while suppressing deterioration in drivability.

Here, the first invention can be embodied, for example, like the second invention. A second invention includes a shift position determination unit that determines whether the shift position of the vehicle is in a movement range in which movement of the vehicle is instructed;
a brake determination unit that determines whether or not the driver is operating the brake;
a speed determination unit that determines whether the vehicle is in a stopped state or an extremely low speed state based on the information acquired by the speed acquisition unit;
The driving force determination unit determines that the shift position is in the movement range, that the brake operation is being performed, and that the vehicle is in a stopped state or an extremely low vehicle speed state. If so, it is determined that there is no intention.

When the shift position is in the movement range, by stopping the switching control of the inverter when the driver intends to stop, it is possible to reduce the power consumption of the inverter while suppressing a decrease in drivability. Here, the inventor of the present application proposed that the conditions for accurately understanding the driver's intention to stop are that the driver is operating the brakes, and that the vehicle is at a halt or at an extremely low speed. found it to be appropriate.

Therefore, the driving force determination unit of the second invention is configured to operate when the shift position is determined to be in the movement range, the driver is determined to have applied the brakes, and the vehicle is in a stopped state or at an extremely low vehicle speed. If it is determined that the user is in the state, it is determined that the user does not have the above intention. Thereby, switching control can be stopped reflecting the driver's intention to stop, and power consumption of the inverter can be reduced while suppressing deterioration in drivability.

Here, the first invention can be embodied as, for example, the third invention. A third invention includes a torque acquisition unit that acquires information regarding the output torque of the rotating electric machine,
When the driving force determination unit determines that the vehicle is coasting based on the information acquired by the speed acquisition unit and the information acquired by the torque acquisition unit, the driving force determination unit determines that there is no intention. .

According to the third invention, it is also possible to determine that the driver has no intention. Thereby, it is possible to reduce power consumption of the inverter while suppressing deterioration in drivability.

FIG. 1 is an overall configuration diagram of an in-vehicle system according to a first embodiment. 5 is a flowchart showing a procedure of processing executed by a control unit. 5 is a time chart showing an example of a switching control mode of an inverter. FIG. 3 is an overall configuration diagram of an in-vehicle system according to a second embodiment. 5 is a flowchart showing a procedure of processing executed by a control unit. 5 is a time chart showing an example of a switching control mode of an inverter.

<First embodiment>
DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a control device according to the present invention will be described below with reference to the drawings. The control device of this embodiment is installed in a vehicle such as a hybrid vehicle or an electric vehicle that uses a rotating electric machine as a driving power source.

As shown in FIG. 1, the vehicle 10 includes a rotating electric machine 20, an inverter 30, a contactor 31, and a storage battery 32 as a power storage device. In this embodiment, the rotating electrical machine 20 has a three-phase stator winding 21 and a rotor 22, and is, for example, a permanent magnet type synchronous machine.

Vehicle 10 includes a transmission 23, a drive shaft 24, and drive wheels 25. The rotor 22 of the rotating electrical machine 20 is capable of transmitting power to drive wheels 25 via a transmission 23 and a drive shaft 24 . In other words, the rotating electric machine 20 serves as a driving power source for the vehicle 10.

The stator winding 21 of the rotating electrical machine 20 is electrically connected to a storage battery 32 via an inverter 30 and a contactor 31. The inverter 30 has upper and lower arm switches. The storage battery 32 is an assembled battery consisting of a plurality of cells connected in series, and is, for example, a secondary battery such as a lithium ion storage battery or a nickel-hydrogen storage battery.

The vehicle 10 includes a brake sensor 40, a shift position sensor 41, a rotation angle sensor 42, and an eco mode switch 43. The brake sensor 40 detects the brake stroke Sb, which is the amount of depression of the brake pedal, which is a brake operation member, by the driver.

Shift position sensor 41 detects the shift position of transmission 23. This shift position is operated by the driver. The shift positions in this embodiment include a parking range (P range) used when parking the vehicle 10, a reverse range (R range) used to instruct the vehicle 10 to move backward, and a power transmission range between the rotor 22 and the drive shaft 24. The range includes a neutral range (N range) that is cut off, a drive range (D range) that instructs the vehicle 10 to move forward, and a brake range (B range) that instructs the vehicle 10 to move forward. The B range is a range in which the braking force applied to the wheels by regenerative drive control is set to be greater than the D range when the driver does not press down on the accelerator pedal as an accelerator operating member.

The rotation angle sensor 42 detects the rotation angle (electrical angle) of the rotor 22, and is, for example, a resolver. The eco mode switch 43 is a switch that instructs to switch the driving mode to the power saving mode, and is turned on or off by the driver. When the eco-mode switch 43 is turned on, control for saving power of in-vehicle equipment including the inverter 30 is permitted. The detected values of each of the sensors 40 to 42 and the operating state of the eco mode switch 43 are transmitted to a control unit 50 included in the vehicle 10.

In order to control the torque generated by the rotating electric machine 20 to the command torque Trq*, the control unit 50 controls the upper and lower parts of the inverter 30 based on the detected values of the rotation angle sensor 42 and the like while the contactor 31 is turned on. Performs arm switch switching control. Specifically, the control unit 50 performs power running drive control, which is switching control that converts the DC power output from the storage battery 32 into AC power and supplies the AC power to the stator winding 21. When this control is performed, the rotating electric machine 20 functions as an electric motor and generates power running torque. Further, the control unit 50 performs regenerative drive control, which is switching control that converts AC power generated by the rotating electrical machine 20 into DC power and supplies the DC power to the storage battery 32. When this control is performed, the rotating electrical machine 20 functions as a generator and generates regenerative torque. Braking force is applied to the wheels by the regenerative torque.

FIG. 2 shows a procedure for switching control processing of the inverter 30 executed by the control unit 50. This process is repeatedly executed, for example, at a predetermined control cycle.

In step S10, it is determined whether the shift position detected by the shift position sensor 41 is in the D range, B range, R range, or N range. In this embodiment, the process of step S10 corresponds to a "shift position determination section".

If an affirmative determination is made in step S10, the process proceeds to step S11, where it is determined whether the brake stroke Sb detected by the brake sensor 40 is larger than the brake threshold value Sth (>0). The process in step S11 is a process for determining whether or not the driver is performing a brake operation (that is, whether or not the driver is depressing the brake pedal). In addition, in this embodiment, the process of step S11 corresponds to the "brake determination section".

If an affirmative determination is made in step S11, it is determined that a brake operation is being performed, and the process proceeds to step S12. In step S12, it is determined whether the vehicle 10 is in a stopped state or an extremely low vehicle speed state. In this embodiment, the detected value of the rotation angle sensor 42 is acquired, and the rotational speed of the rotor 22 (hereinafter referred to as motor rotational speed Nm) is calculated based on the acquired detected value. Then, based on the calculated motor rotational speed Nm, it is determined whether the vehicle is in a stopped state or an extremely low vehicle speed state.

Specifically, when it is determined that the motor rotational speed Nm is less than the first speed threshold value Nth1 (>0) near 0, it is determined that the traveling speed of the vehicle 10 is equal to 0, and the vehicle 10 is in a stopped state. It is determined that

On the other hand, if it is determined based on the motor rotational speed Nm that the traveling speed of the vehicle 10 is 3 km/h or more and less than the predetermined speed set to a value of 4 km/h or less, the vehicle 10 is It is determined that the vehicle is in a speed state. Specifically, when it is determined that the motor rotational speed Nm is less than the second speed threshold Nth2, which is larger than the first speed threshold Nth1, it is determined that the vehicle 10 is in an extremely low speed state. The second speed threshold Nth2 is set to a value that allows it to be determined whether the traveling speed of the vehicle 10 is less than a predetermined speed. In this embodiment, the process of step S12 corresponds to a "velocity acquisition unit" and a "velocity determination unit".

If it is determined in step S12 that the vehicle is in a stopped state or an extremely low vehicle speed state, the process proceeds to step S13, and the command torque Trq* (specifically, the absolute value of the command torque Trq*) of the rotating electrical machine 20 is equal to or less than the torque threshold value. It is determined whether or not it is less than Tth. The process in step S13 is a process for determining whether the command torque Trq* is equal to zero.

If an affirmative determination is made in step S13, it is determined that the command torque Trq* is equal to 0, and the process proceeds to step S14. In step S14, it is determined whether the eco mode switch 43 is turned on.

If a negative determination is made in any of steps S10 to S14 in a situation where switching control of the upper and lower arm switches constituting the inverter 30 is being performed, the process advances to step S16 and switching control is continued. Note that in this embodiment, the processing in steps S10 to S13 corresponds to a "driving force determination section".

On the other hand, if an affirmative determination is made in step S14 in a situation where switching control is being performed, the process proceeds to step S15 and the switching control is stopped. This keeps the upper and lower arm switches of each phase off. In addition, in this embodiment, the process of step S15 corresponds to a "stop part".

After stopping the switching control in step S15, if a negative determination is made in any of steps S10 to S14, the process advances to step S16 and switching control is restarted. In addition, in this embodiment, the process of step S16 corresponds to a "resuming part".

Incidentally, until a predetermined period has elapsed after stopping the switching control in step S15, even if an affirmative determination is made in any of steps S10 to S14, the process does not proceed to step S16 and the switching control continues to be stopped. It's okay. Here, the predetermined period may be set to a period longer than the control cycle of the control unit 50, for example.

Next, switching control of the inverter 30 will be explained using FIG. 3. 3(a) shows changes in the motor rotational speed Nm, FIG. 3(b) shows changes in the brake stroke Sb, and FIG. 3(c) shows changes in the switching state of the inverter 30. Note that in the example shown in FIG. 3, the eco mode switch 43 is turned on.

Switching control is performed in a period before time t1. At time t1, it is determined that the brake stroke Sb has become larger than the brake threshold Sth. After that, the traveling speed of the vehicle 10 gradually decreases, and at time t2, it is determined that the vehicle 10 is in a stopped state. Furthermore, since affirmative determinations are made in steps S13 and S14, switching control of the inverter 30 is stopped.

Thereafter, at time t3, a negative determination is made in step S11, and switching control is restarted through the processing in step S16. However, in the example shown in FIG. 3, if the control unit 50 determines that the brake stroke Sb has become equal to or less than the release threshold Sα, which is larger than the brake threshold Sth, a negative determination is made in step S15. By setting the release threshold Sα to be larger than the brake threshold Sth, it is possible to quickly determine that the brake operation has been released.

According to this embodiment described in detail above, the following effects can be obtained.

The control unit 50 determines that the shift position is in the D range, B range, or R range, and determines that the brake stroke Sb is larger than the brake threshold value Sth, and the vehicle 10 is in a stopped state or in an extremely low The switching control of the inverter 30 is stopped on condition that the vehicle speed is determined to be high. Thereby, power consumption of the inverter 30 can be reduced while suppressing deterioration in drivability.

When the switching control is stopped and a negative determination is made in step S11, the control unit 50 restarts the switching control in order to cause the rotating electric machine 20 to generate torque and start or move the vehicle 10 backward. Thereby, after accurately understanding the driver's intention to start, it is possible to promptly restart the switching control and start starting or reversing the vehicle 10. Therefore, deterioration in drivability can be further suppressed.

<Second embodiment>
The second embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, the method for determining whether or not the driver of the vehicle 10 has an intention to generate the driving force for the vehicle 10 by controlling the drive of the rotating electric machine 20 is changed.

FIG. 4 shows the overall configuration of the system according to this embodiment. Note that in FIG. 4, the same components as those shown in FIG. 1 above are given the same reference numerals for convenience.

The vehicle 10 includes an accelerator sensor 44 and a slope information detection section 45. The accelerator sensor 44 detects an accelerator stroke Sa that is the amount of depression of an accelerator pedal, which is an accelerator operating member, by the driver.

The slope information detection unit 45 detects slope information of the road on which the vehicle 10 travels. The slope information detection unit 45 may be configured by, for example, a sensor that detects the slope of the driving path or a process that acquires the slope of the driving path from map information. The detection values of the accelerator sensor 44 and the slope information detection section 45 are input to the control section 50.

In this embodiment, the control unit 50 is capable of implementing vehicle speed maintenance control (cruise control) and vehicle distance maintenance control as driving support control for the vehicle 10. Vehicle speed maintenance control is control that causes the host vehicle to travel at a constant speed. Vehicle distance maintenance control is control to maintain a constant distance between the preceding vehicle and the own vehicle.

FIG. 5 shows a procedure for switching control processing of the inverter 30 executed by the control unit 50. This process is repeatedly executed, for example, at a predetermined control cycle.

In step S20, based on the accelerator stroke Sa detected by the accelerator sensor 44, it is determined whether the accelerator is being operated (that is, whether the accelerator pedal is being depressed).

If it is determined in step S20 that the accelerator operation has not been performed, the process proceeds to step S21, where the command torque Trq* (specifically, the absolute value of the command torque Trq*) of the rotating electrical machine 20 is acquired, and the acquired command It is determined whether the torque Trq* is less than the torque threshold Tth. The process in step S21 is a process for determining whether the command torque Trq* is equal to 0, similar to step S13 in FIG. Note that the process in step S21 corresponds to a "torque acquisition section".

If an affirmative determination is made in step S21, it is determined that the command torque Trq* is equal to 0, and the process proceeds to step S22. In step S22, one of the first conditions is that the vehicle speed maintenance control is canceled while the vehicle speed maintenance control is being performed, and the second condition is that the control is canceled while the vehicle distance maintenance control is being performed. , it is determined whether any of them hold true. If it is determined that either the first or second condition is satisfied, it is determined that the driver of the vehicle 10 has an intention to generate the driving force for the vehicle 10, and the process proceeds to step S25.

If a negative determination is made in step S22, the process proceeds to step S23, and based on the motor rotational speed Nm and the slope information detected by the slope information detection unit 45, it is determined that the vehicle 10 is running inertia. It is determined whether or not it is possible to make a definitive determination. In this embodiment, the process of step S23 corresponds to a "velocity acquisition unit".

For example, in a situation where it is determined that the vehicle 10 is traveling on a flat road based on gradient information, if it is determined that the motor rotation speed Nm is decreasing, it is determined that the vehicle 10 is decelerating, and the vehicle 10 is coasting. It is also possible to make a definite determination that it is inside. Specifically, for example, in a situation where it is determined that the vehicle 10 is traveling on a flat road, if it is determined that the rate of decrease in the motor rotational speed Nm is equal to or higher than a predetermined speed, it is determined that the vehicle 10 is coasting. All you have to do is make a definitive determination. Note that in a situation where it is determined that the vehicle 10 is traveling on an uphill road surface based on the slope information, the predetermined speed is set higher than when it is determined that the vehicle 10 is traveling on a flat road. You may.

For example, if it is determined that the motor rotation speed Nm is approximately constant in a situation where it is determined that the vehicle 10 is traveling on a road surface with a downward slope based on the slope information, the vehicle 10 is coasting. You may also make a definitive determination that there is.

In a situation in which switching control of the upper and lower arm switches constituting the inverter 30 is performed, if an affirmative determination is made in step S20 or S22, or a negative determination is made in step S21 or S23, the process proceeds to step S25, and the switching control is performed. Continue.

On the other hand, in a situation where switching control is being performed, if an affirmative determination is made in step S23, the process proceeds to step S24 and the switching control is stopped.

After stopping the switching control in step S24, if an affirmative determination is made in step S20 or S22, or a negative determination is made in step S21 or S23, the process proceeds to step S25 and the switching control is restarted. Note that in this embodiment, the process of step S25 corresponds to a "resuming section". Further, the processing in steps S20 to S23 corresponds to a "driving force determination section".

Incidentally, as in the first embodiment, until the predetermined period has elapsed after switching control is stopped in step S25, even if an affirmative determination is made in step S20 or S22 or a negative determination is made in step S21 or S23, , the switching control may continue to be stopped without proceeding to step S25.

Next, switching control of the inverter 30 will be explained using FIG. 6. FIG. 6(a) shows the transition of the command torque Trq*, FIG. 6(b) shows the transition of the motor rotation speed Nm, FIG. 6(c) shows the transition of the brake stroke Sb, and FIG. 6(d) shows the transition of the brake stroke Sb. 6(e) shows the transition of the driving state of the vehicle 10, and FIG. 6(e) shows the transition of the switching state of the inverter 30. Note that FIG. 6 shows each transition when the vehicle 10 is traveling on a flat road.

In a period before time t1, the vehicle 10 is in an accelerated state due to the power running drive control being implemented. At time t1, it is determined that the accelerator is not operated and the command torque Trq* is less than the torque threshold Tth. Furthermore, at time t1, it is determined that the motor rotational speed Nm is decreasing. Thereby, it is determined that the vehicle 10 is coasting, and the switching control is stopped.

Thereafter, at time t2, the switching control is restarted, and the vehicle 10 is brought into an accelerated state. Thereafter, at time t3, the switching control is stopped again as in the case of time t1.

Thereafter, at time t4 during coasting, regenerative drive control is started, and then at time t5, the vehicle 10 is brought to a stopped state or an extremely low vehicle speed state.

Also according to the present embodiment described above, it is possible to reduce the power consumption of the inverter 30 while suppressing a decrease in drivability.

<Other embodiments>
Note that each of the above embodiments may be modified and implemented as follows.

- The shift position when an affirmative determination is made in step S10 of FIG. 2 may be any one or two of the D range, B range, and R range.

- The process of step S12 in FIG. 2 may be replaced with a process of determining whether the vehicle 10 is in a stopped state or a process of determining whether the vehicle 10 is in an extremely low speed state.

- Both steps S13 and S14 in FIG. 2 may be deleted. In this case, when the control unit 50 makes an affirmative determination in step S12, the process proceeds to step S15. Furthermore, either one of steps S13 and S14 may be deleted.

- The detected value used to determine whether the vehicle 10 is in a stopped state or an extremely low vehicle speed state is not limited to the detected value of the rotation angle sensor 42. For example, a sensor that detects the rotation speed of the power transmission system from the rotor 22 to the drive wheels 25, such as the rotation speed of the input/output shaft of the transmission 23, the rotation speed of the drive shaft 24, and the rotation speed of the drive wheels 25 (wheels). It may be a detected value.

- At least one of steps S22 and S23 in FIG. 5 may be deleted.

- The value to be compared with the torque threshold Tth in step S13 in FIG. 2 or step S21 in FIG. The value may be calculated by a torque calculation unit that calculates torque.

- The power storage device is not limited to a storage battery, and may be, for example, a large capacity capacitor.

- The inverter 30 and the storage battery 32 may be electrically connected via a DC/DC converter. This DCDC converter boosts the output voltage of the storage battery 32 and supplies it to the inverter 30, or steps down the voltage from the inverter 30 and supplies it to the storage battery 32.

- The control unit and the method described in the present disclosure are implemented by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. May be realized. Alternatively, the controller and techniques described in this disclosure may be implemented by a dedicated computer provided by a processor configured with one or more dedicated hardware logic circuits. Alternatively, the control unit and the method described in the present disclosure may be implemented using a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. It may be implemented by one or more dedicated computers configured. The computer program may also be stored as instructions executed by a computer on a computer-readable non-transitory tangible storage medium.

DESCRIPTION OF SYMBOLS 10... Vehicle, 20... Rotating electric machine, 25... Driving wheel, 30... Inverter, 32... Storage battery, 50... Control part.

Claims (4)

A power storage device (32),
an inverter (30) electrically connected to the power storage device;
Applied to a vehicle (10) comprising a stator winding (21) electrically connected to the inverter, and a rotating electric machine (20) having a drive wheel (25) and a rotor (22) capable of transmitting power. In the vehicle control device (50),
a shift position determination unit that determines whether the shift position of the vehicle is in a movement range in which movement of the vehicle is instructed;
a brake determination unit that determines whether or not the driver is operating the brake;
a speed acquisition unit that acquires information regarding the traveling speed of the vehicle;
a speed determination unit that determines whether the vehicle is in a stopped state or an extremely low speed state based on the information acquired by the speed acquisition unit;
a driving force determination unit that determines whether a driver of the vehicle has an intention to generate driving force for the vehicle by controlling the drive of the rotating electric machine;
a stop unit that turns off upper and lower arm switches of each phase of the inverter and stops switching control on the condition that the driving force determination unit determines that there is no intention ;
The driving force determining unit determines that the shift position is in the movement range, that the brake operation is being performed, and that the vehicle is in a stopped state or an extremely low vehicle speed state. If the determination is made, the vehicle control device determines that there is no intention . The vehicle control device according to claim 1 , wherein the movement range is a range that instructs the vehicle to move forward. When the switching control is stopped by the stopping unit and the driving force determining unit determines that there is the intention, the switching control is performed to generate torque in the rotating electric machine and start moving the vehicle. The vehicle control device according to claim 1 or 2, further comprising a restart section that restarts control. A power storage device (32),
an inverter (30) electrically connected to the power storage device;
a rotating electric machine (20) having a stator winding (21) electrically connected to the inverter, a drive wheel (25), and a rotor (22) capable of transmitting power;
In a program applied to a vehicle (10) comprising a computer,
to the computer;
A process of determining whether the shift position of the vehicle is in a movement range that instructs movement of the vehicle;
A process for determining whether or not the driver is operating the brakes;
a process of acquiring information regarding the traveling speed of the vehicle;
A process of determining whether the vehicle is in a stopped state or an extremely low speed state based on the acquired information;
Driving force determination processing for determining whether a driver of the vehicle has an intention to generate driving force for the vehicle by controlling the drive of the rotating electric machine;
on the condition that it is determined that there is no intention, execute a process of turning off upper and lower arm switches of each phase of the inverter and stopping switching control;
The driving force determination process is performed when it is determined that the shift position is in the movement range, that the brake operation is being performed, and that the vehicle is in a stopped state or an extremely low speed state. If the determination is made, the program determines that there is no intention.

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