JP2021035161A - Electric motor vehicle control device and method of the same - Google Patents

Abstract

To provide an electric motor vehicle control device which can start in an advance direction without largely retreating in an upward gradient environment or the like and without generating the large impulse.SOLUTION: An electric motor vehicle control device comprises: a start-up torque output unit 12 which outputs torque T in an advance direction to a motor 4 of an electric motor vehicle 11 that is retreating in accordance with a need of reversing the travel direction of the electric motor vehicle 11 from a retreat to an advance; and a reverse impact alleviation unit 13 which reduces the torque T to a target value β when an absolute value of an advance speed V is smaller than a prescribed value α during the retreat. The reverse impact alleviation unit 13 reduces the torque T to the target value β when the retreat speed V is equal to or less than the prescribed value α while the retreat of the electric motor vehicle 11 is ceasing. With this, the impulse that occurs in the electric motor vehicle 11 at the start-up on a slope from the retreat state can be suppressed. Consequently, the electric motor vehicle 11 can start-up in the advance direction without largely retreating on the upward gradient and without generating the large impulse.SELECTED DRAWING: Figure 1

Description

The present invention relates to an electric vehicle control device for controlling an electric motor for driving an electric vehicle and a method thereof.

According to Patent Document 1, when a reverse movement motion that does not match the target rotation speed is detected in an electric vehicle, the speed command value is reset to a value lower than the initial value to prevent an excessive driving force from being output. A drive control device for an electric vehicle is described.

Japanese Unexamined Patent Publication No. 2003-134611

The technique described in Patent Document 1 realizes a smooth starting operation from a backward state by mainly suppressing an excessive driving force when starting on a slope from the viewpoint of a user of an electric wheelchair. The electric wheelchair is designed to distribute the driving force to the weight of the controlled object so that it can overcome steep slopes, etc., assuming some unreasonable usage conditions. Therefore, when the control target is an electric wheelchair, it is not necessary to set a target value of the driving force, and only the driving force control based on the speed difference between the constantly monitored current speed and the target speed can be used to improve the riding comfort of the electric wheelchair. Usability can be satisfied to some extent.

However, in the case of a controlled object such as a railroad vehicle, which is much heavier than an electric wheelchair, the slope angle for starting on a slope and the weight of the vehicle may be within the specified range, and the distribution of driving force to the weight of the controlled object is Different from electric wheelchairs. When driving force control based on a speed difference such as an electric wheelchair is adopted for railway vehicles under different conditions in this way, even if the slope is within the specified range, the driving force enough to start on a slope cannot be secured and the vehicle starts. There are things you can't do. On the other hand, railroad vehicles may require a driving force that exceeds the value set by the speed difference so that they can overcome it. In such a railroad vehicle, when a driving force exceeding a value set by a speed difference is output and powering is performed, a large impulse may be generated and the riding comfort may be deteriorated.

The present invention has been made in view of the above problems, and an object of the present invention is to control an electric vehicle that can be started in the forward direction without significantly retreating in an uphill environment or the like and without generating a large impulse. To provide the equipment.

The present invention that solves the above problems is an electric vehicle control device that controls an electric motor that drives an electric vehicle, and is an electric vehicle that is moving backward as necessary to reverse the traveling direction of the electric vehicle from backward to forward. It is equipped with a starting torque output unit that outputs torque in the forward direction to the electric motor, and a reversing impact mitigation unit that reduces the torque to the target value when the absolute value of the traveling speed becomes smaller than a predetermined value during retreat. is there.

According to the present invention, while the retreat of the electric vehicle is stopping due to the action of the starting torque output unit, the reversing impact mitigation unit reduces the torque to the target value when the retreat speed becomes equal to or less than a predetermined value. Then, the urge generated in the electric vehicle at the time of starting from the retreating state to the start on the slope can be suppressed. As a result, the electric vehicle can be started in the forward direction without retreating significantly in an uphill environment or the like and without generating a large impulse.

FIG. 1A is a block diagram showing a schematic configuration of an electric vehicle control device (this device) according to an embodiment of the present invention. FIG. 1B is a block diagram showing a schematic configuration of an inverter device controlled by this device and a permanent magnet synchronous motor (PMSM). It is a flowchart which showed the process of this apparatus. It is a time chart showing the operation and effect of this device in comparison with the conventional example, and shows the output torque, the speed change rate, the jerk, and the vehicle speed of the electric motor.

Hereinafter, an embodiment of the present invention will be illustrated with reference to the drawings. The electric vehicle control device according to the embodiment of the present invention is abbreviated as "this device". Further, although the PSMS electric motor is illustrated, an induction motor or other type may be used.

FIG. 1A is a block diagram showing a schematic configuration of an electric vehicle control device (this device) according to an embodiment of the present invention. As shown in FIG. 1A, the electric vehicle 11 to which the present device 10 is applied includes an inverter device 2, an electric motor 4, a speedometer 5, and a torque detection unit 6 in addition to the present device 10. Be prepared. The speedometer 5 detects the traveling speed V of the electric vehicle 11. The torque detection unit 6 detects the torque T applied to the wheels by the electric motor 4.

The device 10 controls the output of the inverter device 2, controls the torque T applied to the wheels by the electric motor 4, and controls the rotation speed, and controls the traveling speed V of the electric vehicle 11. The inverter device 2 constantly inputs the detected values of the torque T and the traveling speed V and uses them for feedback control.

FIG. 1B is a block diagram showing a schematic configuration of an inverter device 2 and an electric motor 4 controlled by the present device 10. The control system of the present device 10 includes a control logic unit 1 that outputs a control command based on a signal from an external device, a power unit INV controlled by a gate signal 7 from the control logic unit 1, and a current of a main circuit or the like. It is composed of a current / voltage measuring unit 3 for measuring a voltage and an electric motor 4 for driving a vehicle by passing a current from a power unit INV. The four PMSM_A to D shown in FIG. 1B are collectively referred to as the electric motor 4.

Further, the control logic unit 1 includes a starting torque output unit 12 and a reversing impact mitigation unit 13. The starting torque output unit 12 causes the electric motor 4 of the retreating electric vehicle 11 to output the torque T in the forward direction, as will be described later with reference to FIG. The reversing impact mitigation unit 13 torques T when the absolute value of the traveling speed V becomes smaller than the predetermined value α while the electric vehicle 11 is retreating, or at the timing J when the traveling speed V = the predetermined value α. To the target value β. The starting torque output unit 12 and the reversing impact mitigation unit 13 are functions provided in the control logic unit 1 for convenience of explanation, and have a configuration as clearly distinguished by the block of FIG. 1 (b). No need.

FIG. 2 is a flowchart showing the processing of the present device 10. As shown in FIG. 2, the processing of the apparatus 10 includes a notch-off step S1, a power running command step S2, a step S3 for determining whether or not the power running state is in the retracted state, and a step S4 for outputting the power running torque T. The step S5 for determining whether or not the predetermined speed α has been reached, the step S6 for controlling the torque T to the target value β, the step S7 for determining whether or not the torque T is in the forward state, and the power running torque T are output. It has step S8 and. More details are as follows.

When it is necessary to start the electric vehicle 11 on a slope on an uphill slope, the electric vehicle 11 is advanced by first releasing the brake, passing through a notch-off (S1), and outputting a power running command (S2). At this time, the control logic unit 1 actually determines the direction in which the control logic unit 1 intends to proceed from the speed V information calculated by the control logic unit 1 using the measured values of the current / voltage measurement unit 3. It is determined whether or not the electric vehicle 11 is traveling in the forward direction.

That is, in the driver's cab of the electric vehicle 11 on an uphill slope, the driver operates the electric vehicle 11 so as to advance in the forward direction for starting on a slope. At that time, the control logic unit 1 can determine whether the value of the speed V is positive or negative depending on whether the electric vehicle 11 is retreating in the downward direction or starting in the upward direction.

When the control logic unit 1 determines that the vehicle is traveling in the opposite direction, the control logic unit 1 outputs a command to output the power running torque T equivalent to that when the vehicle is traveling in the forward direction according to the weight of the vehicle. Then (S4), the command is input to the power unit INV. The power unit INV outputs a current value according to the input command value, and when the current is input to the electric motor 4, the power running torque T corresponding to the command is output.

When the power running torque T is applied to the wheels of the electric train 11 in the forward direction, the retreat speed V in the direction of going down the uphill becomes slow. Next, in the electric vehicle 11, the control logic unit 1 determines that the speed V = the predetermined value α while the absolute value of the retreating speed V approaches zero (Yes in S5). At that time, in step S6, the control logic unit 1 outputs a command to reduce the torque T to the target value β, the command value is input to the power unit INV, and the power unit INV is a current value having a value adapted to the command value. Is output, and the current value thereof is input to the electric motor 4, so that the electric motor 4 reduces the torque T to the target value β. The target value β is set to a numerical value calculated by the control logic unit 1 based on the weight and running resistance of the vehicle, that is, the friction between the wheels and the railroad track, and the meshing resistance of the drive gears by an arithmetic expression ( S6).

By such control of the present device 10, a current is input to the electric motor 4, torque T corresponding to a command is output, timing X of switching from the backward state to the forward state, or an impulse generated shortly before the timing X is suppressed, and electricity is generated. The car 11 can move forward. After that, when the control logic unit 1 determines that the vehicle is moving forward (Yes in S7), the control logic unit 1 issues a command to increase the torque T in step S8. Upon receiving this, the power unit INV outputs a current having a value corresponding to the command value input to the control logic unit 1, and the current having this value is input to the electric motor 4. As a result, the torque T corresponding to the command is output from the electric motor 4 (S8).

FIG. 3 is a time chart showing the operation and effect of the apparatus 10 in comparison with the conventional example, and the horizontal axis is a common time axis. On the vertical axis, four types of variables are shown in order from the top. The first from the top is the output torque T of the electric motor 4. The second from the top is the speed change rate Z, which can be read as acceleration. Even if the linear change is good, if it is non-linear or discontinuous, it is considered to cause deterioration of riding comfort. The third from the top is Jerk G, which is considered to be an index value for deterioration of ride quality, so the smaller the value, the better. The fourth from the top is the vehicle speed V of the electric vehicle 11, and if it is equal to or less than zero, it is backward, and if it is greater than zero, it is forward.

In FIG. 3, the effect is clear when the invention of the present device 10 is applied to 8 and the non-applied case 9 is compared. As shown in FIG. 3, the present device 10 reduces the torque T to the target value β when the velocity V reaches the predetermined value α at the time J. As a result, the impact when the electric vehicle 11 reverses from backward to forward is alleviated. When the present invention is not applied 9, the velocity change rate Z changes greatly in a rectangular shape, and the peak value of the jerk G is high.

On the other hand, at the time of application of the present invention 8, the rate of change in velocity Z is relaxed in a stepwise manner, and the peak value of jerk G is reduced to less than half. In particular, the jerk G at a speed V = 0 is reduced by 60% as compared with 9 when the present invention is not applied. That is, at the time of application 8 of the present invention using the present device 10, the riding comfort is clearly improved.

Further, when the electric vehicle 11 has passed the stage of reversing the traveling direction from backward to forward and the reversed electric vehicle 11 is in the forward state, the control logic unit 1 of the present device 10 corresponds to the torque T of the wheel. And increase the speed V of the electric vehicle 11. Regarding this, there is not much difference between 8 when the present invention is applied and 9 when the present invention is not applied. That is, the velocity V increases without a large delay as compared with 9 when the present invention is not applied.

[Summary]
The present device 10 can be summarized as follows.
[1] The present device 10 shown in FIG. 1B controls an electric motor 4 for driving an electric vehicle 11. The device 10 performs the following control as necessary to reverse the traveling direction of the electric vehicle 11 from backward to forward. As shown in FIG. 3, the starting torque output unit 12 outputs the torque T in the forward direction to the electric motor 4 of the electric vehicle 11 that is moving backward. Here, when the absolute value of the traveling speed V becomes smaller than the predetermined value α while the electric vehicle 11 is reversing, or at the timing J when the traveling speed V = the predetermined value α, the reversing impact mitigation unit 13 torques. T is lowered to the target value β.

By setting the target value of the driving force (torque) according to the weight of the controlled object and the resistance when traveling, the present device 10 is traveling in the direction opposite to the direction in which it is intended to travel. Start up with the impulse of the electric vehicle suppressed. By such control, it is possible to start in the forward direction without causing a large retreat in an uphill environment or the like and without generating a large impulse. The fact that the absolute value of the speed V is smaller than the predetermined value α means that the speed V is closer to zero than the predetermined value α regardless of whether the forward speed (+) or the backward speed (-) is used. .. That is, the state of "velocity V = predetermined value α" is a state in which the speed of slow retreat is accurately defined just before reversing from retreat to forward.

[2] In the present device 10, when the electric vehicle 11 is driven in the forward direction, the starting torque output unit 12 outputs the torque T having the target value γ to the electric motor 4. Further, the present device 10 needs to reverse the traveling direction of the electric vehicle 11 from backward to forward until the absolute value of the retreating speed V of the electric vehicle 11 becomes smaller than a predetermined value α in the forward direction. The torque T is increased to the target value γ, which is the same as when the force is applied to the vehicle.

That is, the torque T is strongly increased to the target value γ, which is equal to the normal power running, until the electric vehicle 11 is about to reverse its progress from backward to forward. Even with such control, it is possible to start the vehicle in the forward direction without causing a large retreat in an uphill environment or the like and without generating a large impulse.

[3] However, as described in the above [1], the basic control pattern of the present device 10 is the timing when the absolute value of the traveling speed V becomes smaller than the predetermined value α while the electric vehicle 11 is reversing. This is a control pattern in which J lowers the torque T to the target value β. Although the present device 10 of [3] belongs to this basic control pattern, it may be likely to achieve the purpose of reversing the torque T from backward to forward without reducing the torque T to the target value β. That is, in the present device 10, the speed V is easy at a small stage before the output of the power running torque T (S4 in FIG. 3) exceeds the target value γ equivalent to the power running in the forward direction described in [2] above. May approach zero from the predetermined value α.

There are roughly two possible causes for the small amount of torque T required to reverse the traveling direction of the electric vehicle 11 from backward to forward. The first is that the slope of the track is close to zero and the component force in the direction of retracting the electric vehicle 11 from gravity is small. The second is that the weight of the electric vehicle 11 is relatively light. In such a case, it is not necessary to output the torque T with a strength exceeding the target value γ, which is the same as when the power is driven in the forward direction described in [2] above, and before that, the electric vehicle 11 moves from backward to forward. It may be reversed. In that case, it is natural that the electric vehicle 11 does not retreat significantly in an uphill environment or the like by controlling the reversing impact mitigation unit 13 so as to reduce the torque T to the target value β referred to in the above [1]. Also, it can be activated in the forward direction without generating a large impulse.

[4] Further, in the present device 10, as shown in FIG. 3, it is preferable that the starting torque output unit 12 increases the torque T at the time X when the traveling direction is switched from the reverse direction to the forward direction. Up to the point X when the vehicle reverses from backward to forward, strong torque is likely to deteriorate the ride quality. Since the device 10 is controlled to accelerate strongly after the time point X when it reverses so as to avoid the trouble, it starts in the forward direction without retreating significantly in an uphill environment or the like and without generating a large impulse. The effect of making it is enhanced.

[5] Further, it is preferable that the apparatus 10 further includes a gradient meter (not shown) for detecting the gradient of the track on which the electric vehicle 11 is located. When the gradient meter detects that the gradient is upward with respect to the traveling direction of the electric vehicle 11 and outputs a gradient detection signal, it is preferable to reduce the torque T referred to in the above [1] to the target value β. If the uphill slope is detected, the behavior of the electric vehicle 11 starting on the slope is predicted. Therefore, if the present device 10 controls the impact avoidance, the expected effect and effect can be obtained.

[6] Further, in the present device 10, the target value β of the torque T referred to in the above [1] is preferably a value corresponding to the vehicle body weight of the electric vehicle 11. The torque T required to reverse the traveling direction of the electric vehicle 11 starting on a slope from backward to forward is set to a value according to the component force in the direction of reversing the electric vehicle 11 from gravity based on the gradient of the track. Just do it. That is, the target value β of the above [1] is linked to the magnitude of the target value γ for powering in the forward direction referred to in the above [2], and is proportional to the body weight of the electric vehicle 11.

[7] Further, in the present device 10, the target value β of the torque T referred to in the above [1] is preferably a value corresponding to the friction between the wheel and the railroad track and the meshing resistance of the drive gear. Since these are also related to the magnitude of the target value γ of the above [2], an action effect similar to that of the above [6] can be considered. Therefore, the control logic unit 1 sets the numerical value calculated according to the friction between the wheel and the railroad track and the meshing resistance of the drive gear by the calculation formula.

The electric vehicle control method (the present method) according to the embodiment of the present invention can be summarized as follows.
[8] This method is a method that enables activation in the forward direction without causing a large retreat in an uphill environment or the like and without generating a large impulse. That is, in this method, by setting the target value β of the driving force (torque T) according to the weight of the controlled object and the resistance when traveling, the vehicle is traveling in the direction opposite to the direction in which the vehicle is to be driven. In addition, the electric vehicle 11 is started by suppressing the impulse.

A power running command is issued to the electric train 11 in a state of retreating due to an uphill slope or the like (Yes in S3), and the starting torque output unit 12 outputs torque T to the wheels (S4). The control logic unit 1 determines that the retreat speed V is equal to or less than a predetermined value α, that is, | V | ≦ | α | while the retreat of the electric vehicle 11 is stopping (S5). At the time of such determination (Yes in S5), the reversing impact mitigation unit 13 reduces the torque T to the target value β (S6). Then, the urge generated in the electric vehicle 11 at the time of starting from the backward state to start on the slope can be suppressed. The above-mentioned target value β is a value provided by the control logic unit 1 for the torque T by calculating from the vehicle weight and the running resistance by a predetermined calculation formula (S6).

1: Control logic unit 2: Inverter device 3: Current / voltage measurement unit 4: Electric motor 5: Speedometer, 6: Torque detector unit, 7: Gate signal, 8: Application of the present invention, 9: The present invention Not applied, 10: electric vehicle control device, 11: electric vehicle, 12: starting torque output unit, 13: reversal impact mitigation unit, G: jerk, INV: power unit, V: speed, Z: speed change rate

Claims (14)

It is an electric vehicle control device that controls the electric motor that drives the electric vehicle.
A starting torque output unit that outputs torque in the forward direction to the electric motor of the electric vehicle that is moving backward, as needed, to reverse the traveling direction of the electric vehicle from backward to forward.
A reversing impact mitigation unit that reduces the torque to a target value when the absolute value of the traveling speed becomes smaller than a predetermined value during the retreat.
An electric vehicle control device equipped with. The starting torque output unit raises the torque to a target value equivalent to that when powering in the forward direction until the absolute value of the retreating speed becomes smaller than the predetermined value.
The electric vehicle control device according to claim 1. When the absolute value of the retreating speed falls below the predetermined value before the torque is increased to the same target value as when the force is driven in the forward direction, the reversing impact mitigation unit is said to reach the target value. Reduce torque,
The electric vehicle control device according to claim 2. The starting torque output unit increases the torque when the traveling direction is switched from the reverse direction to the forward direction.
The electric vehicle control device according to claim 1. Further equipped with a gradient meter for detecting the gradient of the track on which the electric vehicle is located,
When the gradient meter detects that the gradient is uphill with respect to the traveling direction of the electric vehicle and outputs a gradient detection signal,
The torque is reduced to the target value.
The electric vehicle control device according to claim 1. The target value of the torque is a value corresponding to the body weight of the electric vehicle.
The electric vehicle control device according to claim 1. The target value of the torque is a value corresponding to the friction between the wheel and the railroad track and the meshing resistance of the drive gear.
The electric vehicle control device according to claim 1. It is an electric vehicle control method that controls the electric motor that drives the electric vehicle.
If necessary, the direction of travel of the electric vehicle is reversed from backward to forward.
The starting torque output unit outputs torque in the forward direction to the electric motor of the electric vehicle that is moving backward, and the torque is output in the forward direction.
The control logic unit determines whether or not the absolute value of the traveling speed becomes smaller than the predetermined value during the retreat, and determines the speed.
When it is determined that the torque has become smaller, the reversing impact mitigation unit reduces the torque to the target value.
Electric vehicle control method. During the period when the result of the speed determination by the control logic unit is larger than the predetermined value,
The torque is increased to a target value equivalent to that when the starting torque output unit is forced to run in the forward direction.
The electric vehicle control method according to claim 8. The control logic unit determines whether or not the target value equivalent to that when the starting torque output unit is forced to run in the forward direction in the process of increasing the torque from the notch-off state is reached.
When it is determined that the vehicle has not reached the vehicle and the speed has been determined to have decreased.
The reversing impact mitigation unit reduces the torque to the target value.
The electric vehicle control method according to claim 9. When the control logic unit determines that the traveling direction has been switched from the reverse direction to the forward direction, the starting torque output unit increases the torque.
The electric vehicle control method according to claim 8. The gradient meter determines whether or not the slope is uphill with respect to the traveling direction of the electric vehicle, and the gradient is determined.
When it is determined that the slope is uphill, the reversing impact mitigation unit reduces the torque to the target value.
The electric vehicle control method according to claim 8. The target value of the torque is calculated by the control logic unit according to the vehicle body weight of the electric vehicle by an arithmetic expression.
The electric vehicle control method according to claim 8. The target value of the torque is calculated by the control logic unit according to the friction between the wheel and the railroad track and the meshing resistance of the drive gear by an arithmetic expression.
The electric vehicle control method according to claim 8.

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