JP3830176B2 - Electric vehicle control equipment - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a control device for an electric vehicle, and more particularly to a control device for an electric drive motor for driving an electric vehicle.
[0002]
[Prior art]
In recent years, as disclosed in Japanese Utility Model Publication No. Hei 6-70498, etc., by improving the performance of the permanent magnet, the permanent magnet is used for the rotor, and the position of the rotor is detected to perform optimum control of energization to the stator. Many electric vehicle travel drive systems using synchronous motors (brushless motors) have been proposed.
[0003]
[Problems to be solved by the invention]
However, when the rotor of the motor is locked due to wheel removal or the like in a motor for driving driving in an electric vehicle, a current is continuously supplied to a specific stator, resulting in an increase in power circuit loss. It was.
In view of the above problems, an object of the present invention is to accurately detect a lock state or an overload state of an electric motor and reduce power circuit loss.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, an electric motor, position detecting means for detecting a rotor position of the electric motor, and energization of the electric motor in accordance with an output of the position detecting means. The accelerator operation amount detecting means for detecting the accelerator operation amount of the driver, and a control circuit for controlling the energization amount of the power circuit in accordance with the output of the accelerator operation amount detecting means. the output value of the quantity detection means is equal to or greater than a predetermined value, and when it detects a lock state based on the absence rotation signal of the motor, the technical means that includes a current amount limiting means for limiting the current amount of the power circuit Adopted.
[0005]
According to a second aspect of the present invention, the vehicle includes a braking device that brakes the vehicle and a braking device operation detecting unit that detects the operation of the braking device, and the power supply amount control of the power circuit is operated. You may comprise so that it may be performed.
Further, the energization amount limiting means may be configured to switch the current limit setting value of the power circuit to a value lower than the current setting value.
[0006]
Further, the energization amount limiting means may be configured to switch the set value of temperature protection detection of the power circuit to a value lower than the current set value.
Further, the energization amount limiting means may be configured to provide a first period for intermittent energization and a second period for continuous pause.
Further, the energization amount limiting means may be configured to cancel the output of the position detection means and input a predetermined pseudo rotor position detection signal to the control circuit.
[0007]
[Action]
Since the present invention has the configuration as described above, an accelerator operation amount detection means for detecting the driver's accelerator operation amount, and a control circuit for controlling the energization amount of the power circuit in accordance with the output of the accelerator operation amount detection means. with the door, energization amount limiting means, when the output value of the accelerator operation amount detecting means detects the locked state on the basis of the case where there is no rotation signal at a predetermined value or more, and an electric motor, the current amount of the power circuit Restrict. And a braking device for braking the vehicle and a braking device operation detecting means for detecting the operation of the braking device, wherein the output value of the accelerator operation amount detecting means is equal to or greater than a predetermined value and the braking device is operating. Limit the amount of current in the power circuit.
[0008]
【Example】
Hereinafter, the present invention will be described with reference to embodiments shown in the drawings.
FIG. 1 is an electrical connection diagram showing a first embodiment of the present invention, where 1 is a battery, 2 is a known inverter as a power circuit, semiconductor switches 4, 5, 6, 7, 8, 9 and the semiconductor It consists of diodes 10, 11, 12, 13, 14 and 15 connected in antiparallel to the switch. Reference numeral 16 is a synchronous motor (hereinafter referred to as a motor), 3 is a known resolver for detecting the rotor position of the motor 16, 17 is a control circuit for controlling the inverter 2 and the motor 16, and 20 is an accelerator operation for detecting the operation amount of the accelerator. Quantity detection means, 21 and 22 are comparators, 23 are diodes, 24 and 25 are capacitors, 26, 27 and 28 are resistors, 29 is a transistor, and 30 is a current sensor.
[0009]
The operation of the above configuration will be described.
The control circuit 17 uses the command signal from the accelerator operation amount detection means 20, the feedback signal from the current sensor 30, and the rotor position signal of the resolver 3 as input signals, and supplies PWM gate signals to predetermined semiconductor switches 4-9. This is a known circuit. The power circuit constituted by the semiconductor switches 4 to 9 diodes 10 to 15 constitutes a known three-phase inverter circuit.
[0010]
When the accelerator operation amount detection means 20 depresses an accelerator pedal (not shown), the movable terminal that moves in conjunction with the accelerator depression amount moves upward, and the output voltage of the accelerator operation amount detection means 20 increases. Since the output of the comparator 21 is 0 until the output voltage of the accelerator operation amount detection means 20 reaches a predetermined value, the capacitor 24 is discharged through the diode 23 until the output voltage reaches the predetermined value. On the other hand, a differential circuit composed of the capacitor 25 and the resistor 28 detects a voltage change (rotational state of the motor) of the output signal of the resolver 3 and turns the transistor 29 on and off.
[0011]
As a result, when the output voltage of the accelerator operation amount detection means 20 is equal to or higher than a predetermined value and there is no rotation detection signal from the resolver 3 of the motor 16, the capacitor 24 is charged via the resistor 26 and when the predetermined voltage is reached, The output of the comparator 22 is inverted to 1. The output of the comparator 22 is input to the control circuit 17 and is controlled so that the ON time of the gate signal to each semiconductor switch is shortened so that the pulse width is shorter than the normal pulse width.
[0012]
FIG. 2 is an electrical connection diagram showing a second embodiment, wherein 40 is a braking device operation detecting means of a vehicle braking device, 41 and 42 are comparators 43 and an AND circuit. Since the other configurations are the same as those of the first embodiment shown in FIG. 1, the same reference numerals are given to the respective components, and detailed descriptions thereof are omitted.
The output of the comparator 41 becomes 1 when the output of the accelerator operation amount detection means 20 exceeds a predetermined value. The braking device operation detecting means 40 is interlocked with a side brake (not shown), and the illustrated switch is turned on in the operating state. As a result, the output of the comparator 42 becomes 1. As a result, when the accelerator means 20 is depressed more than a predetermined value while the side brake is operated, the output of the AND circuit 43 becomes 1, and the signal is input to the control device 17, and the pulse width is shorter than the normal pulse width. Control is performed so that the ON time of the gate signal to each semiconductor switch is shortened.
[0013]
FIG. 3 shows a main part of another embodiment as the energization amount limiting means, and is configured to switch the current limit set value.
50 is a comparator, 51, 52, 53 and 54 are resistors, and 55 is a transistor. As in FIG. 1, the comparator 50 compares the output of the current sensor 30 that detects the output signal from the inverter with the voltage as the set value of the voltage dividing circuit composed of the resistors 51 and 52, and compares the output with the current that is higher than the set value. When the output of the sensor 30 increases, the signal is input to the control circuit 17 so that the output of the comparator 50 is set to 1 and the gate signal is cut off.
[0014]
Here, when the output of the comparator 22 becomes 1, the transistor 55 is turned on and the minus side input terminal voltage (comparison voltage) of the comparator 50 is lowered, so that the current limit set value becomes low. By inputting a signal, the current limit set value can be switched as necessary.
FIG. 4 is a diagram showing a main part of still another embodiment of the energization amount limiting means, and shows an embodiment for switching the temperature protection set value.
[0015]
FIG. 4 is obtained by replacing the current sensor 30 in FIG. 3 with a temperature sensor 60. The other configurations are the same as those in FIG. 3, and therefore the same configurations are denoted by the same reference numerals and details thereof. The detailed explanation is omitted.
The temperature sensor 60 detects the temperature of a semiconductor switch or the like in the inverter. When the temperature increases, the output voltage, that is, the input voltage to the comparator 50 increases. The following operations are the same as those in FIG.
[0016]
The temperature difference between the temperature sensor 60 and the semiconductor switch is represented by the loss of the semiconductor switch × the thermal resistance between the temperature sensor 60 and the semiconductor switch. Here, when an overload state occurs in which the rotor is locked, the loss of the semiconductor switch increases from two times to three times the normal time. Therefore, by lowering the detection level of the temperature sensor 60 from the above formula, The maximum temperature can be protected at a predetermined value regardless of the load state.
FIG. 5 shows an example in which a pause section is provided as the energization amount limiting means.
[0017]
Reference numeral 70 denotes a transmitter 71, a resistor, 72 a transistor, and 73 to 78 a diode. When the output of the comparator 22 becomes 1, the transmitter 70 is repeatedly turned on and off in a cycle of, for example, 100 msec. Therefore, even if the control circuit 17 continues to output a PWM signal to a specific semiconductor switch, as shown in FIG. Will be suspended for t1.
FIG. 6 shows an operation of an inverter with a constant period as an energization amount limiting means regardless of the output state of the resolver 3. 80 is an oscillator, 81 and 82 are resistors, and 83 is a transistor. When the output of the comparator 22 becomes 1, the transistor 83 is turned on to block the resolver output. On the other hand, the oscillator 80 starts oscillating, and supplies the rotation signal to the control circuit 17 instead of the resolver 3 to the control circuit 17. As a result, the inverter operates at a constant cycle based on the rotation signal of the oscillator 80 even though the rotor is locked.
[0018]
As described above, the inverter 2 is described as a semiconductor switch. However, the semiconductor switch produces the same function and effect in the present invention in any of transistors, IGBTs, MOSFETs, and the like.
[0019]
【effect】
As described above, in the present invention, the configuration as described above makes it possible to detect the state even when a specific motor is locked due to wheel removal or the like. An increase in loss can be prevented.
[Brief description of the drawings]
FIG. 1 is an electrical connection diagram illustrating an overall configuration of a control device for an electric vehicle motor according to the present invention.
FIG. 2 is an electrical connection diagram illustrating the overall configuration of a control device for an electric vehicle motor, showing the configuration of another energization amount limiting means.
FIG. 3 is an electrical connection diagram showing a main part of energization amount limiting means in another embodiment.
FIG. 4 is an electrical connection diagram showing a main part of energization amount limiting means in another embodiment.
FIG. 5A is an electrical connection diagram illustrating a main part of another energization amount limiting unit, and FIG. 5B is a diagram illustrating an output state of a gate signal to an inverter at that time.
FIG. 6 is an electrical connection diagram showing a main part of energization amount limiting means in another embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Battery 2 Inverter 3 Resolver 4, 5, 6, 7, 8, 9 Semiconductor switch 16 Synchronous motor (motor)
17 Control circuit 20 Accelerator operation amount detection means 30 Current sensor 40 Braking device operation detection means

Claims (1)

An electric motor, position detecting means for detecting a rotor position of the electric motor, a power circuit for energizing the electric motor in accordance with an output of the position detecting means, and an accelerator operation amount detecting means for detecting an accelerator operation amount of a driver And a control circuit for controlling the energization amount of the power circuit in accordance with the output of the accelerator operation amount detection means,
When the output value of the accelerator operation amount detection means is equal to or greater than a predetermined value and there is no rotation signal of the motor , the power supply amount limiting means for limiting the power supply amount of the power circuit is provided ,
The electric vehicle control device, wherein the energization amount limiting means cancels the output of the position detection means and inputs a predetermined pseudo rotor position detection signal to the control circuit .

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