JPS6027245B2 - electric car control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electric vehicle control device having a chopper circuit.

Conventional electric vehicle control equipment uses constant-on period variable frequency control,
There are constant frequency variable on-period control, etc., but in the case of the former constant on-period variable frequency control, in order to reduce the loss during commutation of the chopper circuit, the number of commutations of the chopper circuit is reduced and the chopper circuit is turned on. Since it is necessary to increase the period, the initial commutation capacity of the chopper circuit must be increased, and also in the latter constant frequency variable on-period control, the on-period must be increased in order to rapidly accelerate the electric vehicle. Since it is necessary to increase the current rapidly, there is a drawback that the initial commutation capacity must be increased.

In order to solve the above-mentioned drawbacks, the present invention changes both the on period and off period of the chopper circuit, and the maximum rate of change of the on period is determined by the delay time by the soft start circuit, thereby ensuring continuity during sudden acceleration and reverse braking. By changing the off period using an electric signal that corresponds to the accelerator, it is possible to control the rate change with a relatively small commutation capacity even during sudden acceleration and braking, and at the same time, during sudden acceleration, etc. When the zero start function is not required, the efficiency is improved by quickly raising the frequency to the one with the best overall efficiency, and at maximum efficiency, the on-period is increased to lower the chopping frequency, resulting in control with less chopper loss. The purpose is to provide an electric military control device that can perform

The present invention will be described below with reference to embodiments shown in the drawings.

In FIG. 3, 1 is a reverse braking detection circuit consisting of a switch la that detects reverse braking and turns on, diodes lb and ld, and a resistor lc; 2 is a variable resistor 2a that is linked to an accelerator such as an accelerator pedal or an accelerator lever; An accelerator circuit consisting of a transistor 2b, diodes 2c and 2d, and a resistor 2e, 3 is a capacitor 3a, a resistor 3b for short circuit prevention,
This is a soft start circuit consisting of a first resistor 3c, a second resistor 3d, a resistor 3e, and a diode 3f. 4 is resistance 4
a, 4c, 4g, 4e, transistor 4b, capacitor 4d, discharge circuit 4e that discharges the capacitor 4d when the chopper circuit 11 is turned on, programmable union transistor (product name, hereinafter simply referred to as PUT) 4
An on-pulse oscillation circuit consisting of f generates an on-pulse for turning on the chopper circuit 11.

5 is a transistor 5a, resistors 5b, 5c, 5g, 5h,
An off-pulse oscillation circuit including a capacitor 5d, a discharge circuit 5e that discharges the capacitor 5d when the chopper circuit 11 is turned off, and a PUT 5f generates an off-pulse for turning off the chopper circuit 11.

6 is a forward main circuit switch consisting of a normally open contact 6a, a normally closed contact 6b, and a movable contact 6c; 7 is a field coil 7a;
An electric vehicle drive motor comprising an armature coil 7b,
Reference numeral 8 designates a reverse main circuit switch consisting of a normally open contact 8a, a normally closed contact 8b, and a movable contact 8c, 9 an armature flywheel diode, 10 a motor flywheel diode, and 11 a chopper circuit.

148V is a 48V positive power supply voltage from the DC power supply, 112V is a 12V positive power supply voltage from the DC power supply, and G is a ground terminal to which the negative pole of the DC power supply is connected. Next, the operation of the above configuration will be explained.

One of the forward and reverse main circuit switches 6 and 8 is connected to the normally open contact 6a or 8a, and the other is connected to the normally closed contact 8b or 6b, and the on-pulse oscillation circuit 4 and the off-pulse oscillation circuit 5 are caused to oscillate optically. The chopper circuit 11 is turned on and off to supply electric power to the electric motor 7 and drive the vehicle. Here, the vehicle distance change is performed by changing the conductivity of the chopper circuit 11 by using the accelerator. Now, if the accelerator is suddenly stepped on to request rapid acceleration of the vehicle from the time of startup, the mover c of the variable resistor 2a of the accelerator circuit 2 will move from point a to point b.
It moves toward the point side, and the resistance value of resistor 3b becomes resistor 3c, 3d, 3.
Since it is set to a very small value compared to e, the base voltage yb4 of the transistor 4b of the on-pulse oscillation circuit 4 and the base voltage VQ of the transistor 5a of the off-pulse oscillation circuit 5 are as shown in FIG. 1a. That is, when the accelerator is suddenly depressed and the movable element c of the variable resistor 2a rapidly moves from point a to point b, the emitter potential of the transistor 2b becomes b lower than the potential Vco at point a of the variable resistor 2a. However, after a delay of the charging delay time of the capacitor 3a, the potential at the connection point d on the capacitor 3a side of the first resistor 3c becomes the delayed signal (the base potential of the transistor 5a). ) decreases as shown at Vb5 in FIG. Since the potential VB is obtained by dividing the potential of After changing as shown in FIG. 1a, the voltage decreases to VAo at the voltage division potential at point d, as shown by VL in FIG. Also, if the accelerator is depressed slower than the delay time of the soft start circuit 3, the capacitor 3 of the soft start circuit 3
The delay time due to the charging of transistor a becomes virtually negligible, and the potentials at points d and e of the soft start circuit 3 almost match the change in the emitter potential of the transistor 2b, so that V
becomes = V&, as shown in Figure 1 M, and this first
The time axis in the figure almost coincides with the amount of accelerator operation. Since the potential at each point d, e is applied to the base of each pulse oscillation circuit 5, 4, the change in the oscillation period T, T2 with respect to the potential at point c of each oscillation circuit 4, 5 is caused by the accelerator. If the accelerator is operated suddenly, the result will be as shown in Fig. 2a according to the output of the soft start circuit 3 shown in Fig. 1a, and if the accelerator is gently operated, the soft start will be as shown in Fig. 1b. According to the output of step 3, the result is as shown in FIG. 2b. Here, the oscillation period T2 of the off-pulse oscillation circuit 5
corresponds to the on-period of the chopper circuit 11, and the oscillation period T of the on-pulse oscillation circuit 4 corresponds to the off-period of the chopper circuit 11, respectively, so the conductivity D of the chopper circuit 11 is D-; ), respectively, and the second
The result is as shown by D in Figures a and b. The change in the conductivity of the chopper circuit 11 in the chopper circuit 11 in this case is as shown in FIG. 4, and when the accelerator is depressed slowly as shown in FIG. When the pedal is depressed suddenly as shown in Figure a, the change occurs as shown by the broken line. That is, the maximum rate of change in the off-pulse oscillation period is determined by the time constant of the soft start circuit 3, and the maximum rate of change in the on-pulse oscillation period is determined by the change in the first and second resistors 3c and 3d when the accelerator is suddenly depressed.
Vb5- generated between the terminals of the first resistor 3c due to the voltage division of
In the voltage range of Vb4, it changes in response to the accelerator, and by increasing the chopping frequency and rapidly increasing the conduction rate, torque that satisfies the driver's request is generated and acceleration is improved. In addition, the main circuit switch 6 for forward and reverse
, 8 while the vehicle is running to perform reverse braking, the switch la of the reverse braking detection circuit 1 is turned on and the charge in the capacitor 3a of the soft start circuit 3 is discharged by the output of the reverse braking detection circuit 1. Then, the on-pulse oscillation period is minimized, and the potential at point b of the accelerator circuit 2 is increased, so that the potential VA at the maximum accelerator depression in FIG.
BSVA, SVco. That is, during reverse control, the on period of the chopper circuit 11 is kept constant at the minimum value, and by changing the accelerator, the base voltage of the transistor 4b of the on-pulse oscillation circuit 4 changes from VA to Vco, and the chopper circuit 11 turns off. By changing the period, the braking force during reverse braking can be changed using the accelerator. In addition, since the point d of the soft start circuit 3 is connected to the positive electrode side of the chopper circuit 11 via the resistor 3e and the diode 3f, the charging resistance of the capacitor 3a becomes smaller as the conductivity of the chopper circuit 11 increases. capacitor 3
By linearly changing the charging characteristic at point a, the potentials at point d and point e are changed linearly, so that stable acceleration characteristics can be obtained. In the above embodiment, the output voltages of the accelerator circuit 2 and the soft start circuit 3 are decreased as the accelerator operation amount increases.
By reversing the polarity of each part, the accelerator circuit 2
Of course, it is also possible to increase the output voltage of the soft start circuit 3 as the amount of accelerator operation increases.

As described above, in the device of the present invention, the change in the on period of the chopper circuit is determined by the time constant of the soft start circuit, and the change in the off period is determined by the amount of change that quickly responds to the accelerator only when the accelerator is suddenly depressed. Because of this, the initial commutation capacity can be kept to a small value, and when the driver suddenly operates the accelerator during sudden acceleration, acceleration is improved by outputting a set amount of torque that quickly responds to the accelerator. It has the excellent effect of improving the Furthermore, during reverse braking, the on period of the chopper circuit is set to the minimum value, and the off period is changed to follow the accelerator to change the braking force, so that reverse braking can be performed smoothly and in accordance with the amount of accelerator operation. The commutation capacity is small, and the ripple of the motor current is small, resulting in excellent rectification. In addition, in the control that changes both the conduction period and the non-conduction period of the chopper circuit in this way, the chopping frequency is determined within a range that has good overall efficiency of the motor and chopper circuit, but it is necessary to If a sudden start function is required to transition to a running state, the chopping frequency must be lowered to reduce the conduction rate, but during sudden acceleration, the sudden start function is not necessary and the conduction is reduced as shown by the broken line in Figure 4. Raise the chopping frequency from the low rate state,
The overall efficiency can be improved by keeping this chopping frequency within the efficient range shown by the dashed line.

[Brief explanation of the drawing]

1 and 2 are input voltage characteristic diagrams and operation characteristic diagrams of an on-off pulse oscillation circuit for explaining the operation of the device of the present invention shown in FIG. 3, and FIG. 3 is an electrical diagram showing an embodiment of the device of the present invention The circuit diagram and FIG. 4 are characteristic diagrams of changes in chopping frequency with respect to conductivity in the device of the present invention shown in FIG. 1. ．． ．． ．． ．． - Reverse braking detection circuit, la... switch, 2... accelerator circuit, 3... soft start circuit, 3a... capacitor, 3c... first resistor, 3d...
...Second resistor, 4...On-pulse oscillation circuit, 5...
...Off pulse oscillation circuit, 6...Main circuit switch for forward movement, 7...Electric vehicle drive motor, 8...
...Main circuit switch for reverse, 11...Chopper round trip. Fins Figure 1 Figure 2 / Figure 1 Scales Figure 4

Claims (1)

[Scope of Claims] 1. A main circuit that supplies power from a DC power supply to an electric vehicle driving motor via a chopper circuit, an on-pulse oscillation circuit that generates an on-pulse for turning on the chopper circuit, and An off-pulse oscillator circuit that generates an off-pulse for turning off the accelerator, an accelerator circuit that generates an electric signal according to the amount of operation of the accelerator, and a series connection circuit of a capacitor connected to a DC power source and a first and second resistor. an output side of the accelerator circuit is connected to a connection point between the capacitor and the first resistor, and generates a delay signal that responds to the operation amount of the accelerator with a delay at the connection point; The output side of the accelerator circuit is connected to the connection point of the second resistor, and a half-speed response signal that quickly responds to the operation amount of the accelerator by a voltage corresponding to the voltage drop of the first resistor is sent to this connection point. a soft start circuit that generates a soft start circuit, and applies a delay signal of the soft start circuit to the off-pulse oscillation circuit in order to lengthen the oscillation period of the off-pulse as the amount of operation of the accelerator increases; An electric vehicle control device characterized in that a half-speed response signal of the soft start circuit is applied to the on-pulse oscillation circuit in order to shorten the oscillation period of the on-pulse as the on-pulse increases. 2. A main circuit that supplies power from a DC power supply to an electric vehicle drive motor via a chopper circuit and a forward and reverse main circuit switch for switching the direction of rotation, and an on-pulse to turn on the chopper circuit. an off-pulse oscillation circuit that generates an off-pulse for turning off the chopper circuit; an accelerator circuit that generates an electric signal according to the amount of operation of the accelerator; a capacitor connected to a DC power source; , includes a series connection circuit with a second resistor, the output side of the accelerator circuit is connected to the connection point between the capacitor and the first resistor, and the output side of the accelerator circuit responds to the operation amount of the accelerator with a delay to this connection point. At the same time, the output side of the accelerator circuit is connected to the connection point between the first and second resistors, and the output side of the accelerator circuit is connected to the connection point to generate a delay signal of the accelerator circuit by a voltage corresponding to the voltage drop of the first resistor. It includes a soft start circuit that generates a half-speed response signal that quickly responds to the manipulated variable, and a switch that turns on when it detects that reverse braking is occurring in the motor. and a reverse braking detection circuit for discharging the accelerator circuit and limiting an output value variable range of the accelerator circuit to a maximum response range of the half-speed response signal or less, the oscillation period of the off-pulse is changed as the amount of operation of the accelerator increases. A delay signal of the soft start circuit is applied to the off-pulse oscillation circuit in order to lengthen the oscillation period of the on-pulse, and a half-speed response signal of the soft-start circuit is applied to the on-pulse oscillation circuit in order to shorten the oscillation period of the on-pulse as the amount of operation of the accelerator increases. An electric vehicle control device characterized by applying voltage to an oscillation circuit.