JPS62160001A - Controller for electric railcar - Google Patents

Abstract

PURPOSE:To accurately detect the slip and the slide of an electric railcar by using a reference rotation frequency change rate and a delay time value in response to the speed of the railcar. CONSTITUTION:A rotation frequency change rate detector 10 inputs a pulse signal of a pulse generator 6 and outputs a rotation frequency changer rate DELTAFR. A detecting level calculator 8 outputs a slip detection level or a slide detection level on the basis of the speed signal. Similarly, a delay time calculator 9 outputs a delay time on the basis of the speed signal. A comparator 14 outputs an H level signal when the change rate DELTAFR becomes larger than the output signal of the calculator 8. Then, a delay circuit 15 outputs a slip, the slide signal SL when the H level signal from the comparator 14 continues for the delay time or longer by the calculator 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a control device for an electric vehicle that detects slipping or skidding of drive wheels in the electric vehicle.

[Technical background of the invention and its problems]

Generally, in order to prevent the drive wheels of electric vehicles from slipping or sliding, a slipping/sliding detection device is provided to control the torque of the drive wheels and obtain a predetermined adhesive force between the drive wheels and the rail. The slipping/skidding detection detects the rate of change ΔFR of the rotational frequency of the drive wheel based on a signal from a pulse generator provided on the rotating shaft of the electric motor that drives the drive wheel. Rotational frequency change rate ΔF
When R is detected, it is compared with the slip detection level or the skid detection level. When this rate of change ΔFR remains greater than the detection level for longer than a predetermined time T, it is determined that the drive wheels are slipping or skidding, and slipping/slipping detection is performed.

The slipping/skidding detection level and the predetermined time T are constant values at high speeds and low speeds, and the values are adjusted to values suitable for driving in the low speed range where the torque generated by the drive wheels is large. At high speeds, the vibration of the truck becomes more pronounced than at low speeds, and the rate of change in the rotational frequency of the drive wheels, FR, fluctuates more violently and takes on a larger value than at low speeds. Therefore, a false detection may be made even though the drive wheels are not actually spinning or sliding. If a false detection is made, the torque of the drive wheels is controlled to obtain a predetermined adhesion force between the drive wheels and the rail, which worsens the ride comfort during acceleration, and prevents sufficient braking force from being applied, especially during regeneration control. The problem arises that it is not possible to obtain

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a control device for an electric vehicle that has good accuracy in detecting slipping and skidding and can eliminate deterioration in riding comfort of an electric vehicle due to false detection.

[Summary of the invention]

The present invention provides a first detection means for detecting the rate of change in rotational frequency of the drive wheels of an electric vehicle, and a first calculation means for outputting a reference value of the rate of change in rotational frequency according to the speed of the electric vehicle. Compare the frequency change rate value and the reference value using a comparison means,
When the rotational frequency change rate of the drive wheels exceeds the reference value, the comparison means outputs a signal that is maintained for a predetermined delay time corresponding to the speed output from the second calculation means, and the wheel slips or skids. Provided is a control device for an electric vehicle that outputs a signal from a delay means.

[Embodiments of the invention]

An embodiment based on the present invention will be described using the drawings. 1st
The figure shows a slipping/skidding detection device according to the present invention. The main controller 2 is comprised of a variable voltage, variable frequency inverter and controls the speed of the main motor 3.

The main electric motor 3 drives the drive wheels 4 of the electric vehicle. Main motor 3
A pulse generator 6 that generates pulses in accordance with the rotation is connected to the rotating shaft. The output of the pulse generator 6 is sent to the detection level calculator 8 of the slipping/skidding detection device 1 via the speed detector 7.
and is input to the delay time calculator 9 as well as to the rotation frequency change rate detector 10. The rotation frequency change rate detector 10 is composed of a pulse counter 11, a sampling hold circuit 12, and a change rate calculator 13. The rotational frequency change rate detector 10 and the detection level calculator 8 are connected to a comparator 14. Comparator 14 and delay time calculator 9
is connected to the delay circuit 15. The output of the delay circuit 15 is input to the main controller 2 as a slipping/skidding detection signal.

The operation of the embodiment with the above configuration will be explained.

A pulse generator 6 provided on the rotating shaft of the main electric motor 3 generates pulse signals corresponding to the rotation of the drive wheels 4 at any time. The pulse counter 11 outputs a rotation frequency value by counting the number of pulses per unit time of the pulse signal output by the pulse generator 6. The sampling hold circuit 12 inputs the output signal of the pulse counter 11, and after a predetermined time (sampling time) outputs the same signal as the input signal. The arithmetic unit 13 calculates the rate of change FR from the output value of the pulse counter 11 and the output value FR (ST) of the sampling hold circuit 12 using the following equation and outputs the result.

ΔFR=FR2FR(ST) (ST, sampling time)・ST The pulse signal output from the pulse generator 6 is input to the speed detector 7, and the speed detector 7 detects the speed from the pulse signal, Outputs speed signal. This speed signal is input to the detection level Uratake 8 no. Based on the speed signal, the detection level calculator 8 outputs a slipping detection level FRD when the electric vehicle is moving, and outputs a skidding detection level SRD when regenerative braking is applied. Similarly, the delay time calculation 9 outputs the delay time based on the speed signal.

The detection level calculator 8 and the delay time calculator 9 both input the speed signal from the speed detector 7 and output their respective signals, and their relationship is shown in FIGS. 2(a) and 2(b). As shown in the drawing, as the speed increases, the detection level and delay time increase.

The comparator 14 compares the rate of change ΔF+(of the rotational frequency) with the output signal of the detection level calculator 8, and outputs the 'H level signal when the rate of change ΔFR becomes large. Next, the delay circuit 15
is tH7 if the input is longer than the delay time from the delay time calculator 9 after the lHl level signal is input from the comparator I4.
When the level state continues, a signal at the t Hl level is output, and thereafter the output signal is kept at the 1H level until the signal from the comparator 14 reaches the I L l level. Delay circuit 1
5 is output (Hp level signal is given to the main controller 2 as a slipping/sliding detection signal SL) 6 Main controller 2
performs control to reduce the torque generated by the main motor 3 when the detection signal SL is applied.

The relationship between the rotational frequency change rate ΔFR and the slipping/skidding detection signal SL will be explained using FIG. In FIG. 3(a), HFRD and H3RD are the outputs of the detection level calculator 8, and are the slip detection level and skid detection level during high-speed operation. This slipping/sliding detection level HFRD, H
3RD is a value larger than the detection levels FRD and SRD at low speed. 3rd wheel slipping/sliding detection signal SL during low speed driving
Shown in Figure (b). In the figure, TA is the output value of the delay time calculator 9, which exceeds the detection levels FRD and SRD at time t, which is the value during low-speed operation, and remains above the detection level even after time TA, so the detection signal SL is output,
Time t when the rate of change ΔFR continues to be at or above the detection level
The detection signal SL continues to be output from 2 to t. Similarly, the detection signal SL is output from time t6 to t9.

Next, high-speed operation will be explained. Idling during high-speed operation
The skidding detection signal SL is shown in FIG. 3(c). In the figure, TB is the output value of the delay time calculator 9, which is a value during high-speed operation and is larger than TA during low-speed operation. At time t, the rate of change ΔFR exceeds the detection levels HFRD and H5RD, but falls below the detection level again within the delay time TB, so the detection signal SL is not output. Similarly, at time t, the odor detection level )IFRD,) exceeds IsRD and the delay time T
Even after B, the detection level is higher than the detection level, so the detection signal S
1.L is output and the rate of change ΔFR continues to be higher than the detection level, so 1.L is output from time t7. The detection signal SL is output until During high-speed operation, the detection level and delay time are set to larger values than during low-speed operation, so the values shown in Figure 3 (
At time t of c), the detection signal SL is not output.

That is, in the past, since the detection level and delay time are constant with respect to speed, false detection occurs between times t2 and t3 in FIG. 3(c) during high-speed driving. However, if the detection level and delay time are variable depending on the speed, false detection will not occur at high speeds.

In the above embodiment, the slip detection level and the skid detection level were explained as having the same value, but these are independent values and the values differ depending on the electric vehicle.

[Effects of invention]

According to the present invention, by using a predetermined reference rotation frequency change rate depending on the vehicle speed of the electric vehicle and a predetermined delay time value depending on the vehicle speed, a slipping and skidding detection level corresponding to the speed can be obtained. It is possible to provide a control device for an electric vehicle that has high detection accuracy and can prevent deterioration of riding comfort of the electric vehicle due to false detection.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a slipping/skidding detection device according to an embodiment of the present invention, Fig. 2 is an output waveform diagram of a detection level calculator and a delay time calculator, and Fig. 3 is a rotation of drive wheels during low-speed operation. The rate of change in frequency and the waveform diagram of the slipping/skidding detection signal are shown. 1... Idle/slip detection device 7... Speed detector 8... Detection level calculator 9... Delay time calculator 10... Rotation frequency change rate detector 11... Pulse counter 12...・Sampling hold circuit 13... Rate of change calculator 14... Comparator 15... Delay circuit SL... Slipping/skidding detection signal FRD... Slipping detection level at low speed SRD... At low speed Skidding detection level HFRD...Slip detection level at high speed H3RD...
Skidding detection level TA at high speeds... Delay time TB at low speeds... Delay time at high speeds Agent Patent Attorney Noriyuki Ken Yudo Mitsumata Hirobumi 〃l Araya Diagram 2

Claims (1)

[Claims] A first detection means for detecting a rate of change in the rotational frequency of the driving wheels of an electric vehicle; and a first calculation unit for outputting a reference value of the rate of change in the rotational frequency of the driving wheels according to the speed of the electric vehicle. and a second means for outputting a predetermined delay time value according to the speed of the electric vehicle.
a computation means, a comparison means for outputting a signal when the rotational frequency change rate determined by the first detection means exceeds a reference value determined by the first computation means, and a signal from the comparison means is transmitted to the second computation means. A control device for an electric vehicle, comprising a delay means for outputting a slipping/sliding signal when the signal is output while maintaining a predetermined delay time.