JPS60200702A - Brake controller of electric railcar - Google Patents

Abstract

PURPOSE:To prevent an electric railcar from sliding by decreasing a brake force in a high speed range as compared with that in a low speed range. CONSTITUTION:An armature voltage limiter 21 outputs an armature voltage limiter signal 22 when the armature voltage of a main motor is the prescribed value or higher, a real brake force calculator 15 obtains a regenerative brake force generated from the motor at that time from a main motor current to output a real brake signal 16, and a sliding time conduction rate reducing pattern generator 27 outputs a conduction rate reducing pattern 28 at the sliding time. A chopper controller 4 applies a conduction rate signal 24 in response to a brake force command value 2, a real brake signal 16, an armature voltage limiter signal 21, and a conduction rate reducing pattern 28. A pneumatic brake force controller 3 applies a supplementary brake force command value 17 to a brake force controller 3 in response to the command value 2, and the signals 16 and 22.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an improvement in a brake control device for an electric vehicle, and more particularly to a control technique for an air brake that supplements regenerative braking force controlled by an armature chopper device.

<Technical background of the invention and its problems> When accelerating or decelerating electric cars in recent years, there are many cases in which the frictional force between the rail and the wheels, or what is called ``adhesive force'' in railway engineering, is used to the utmost. .

For example, when the maximum speed is increased while the braking distance of the emergency brake remains constant, or when a machine-priority type automatic train stop device (J2 is referred to as ATC) is installed as a signal safety system, when decelerating. This is the case, for example, when the maximum service brake is frequently used by ATC operation.

When a high deceleration is used, that is, when a high value is used for the adhesion coefficient, which is the ratio of the braking force per axle to the axle load, the frequency of skidding increases, resulting in the occurrence of a sticking phenomenon in which the axle completely locks. As a result, the tread surface of the wheel slips and a so-called flat occurs, causing noise and vibration.

In order to remove this, it is necessary to cut the wheels, which takes many years and also shortens the life of the wheels.

Armature chopper type electric cars are often used on line sections with short distances between stations1, and therefore are often required to have high acceleration/deceleration, resulting in frequent flats.

Figure $1 shows a circuit diagram of a conventional brake control device for electric vehicles that controls regenerative braking using an armature chopper device and supplements this regenerative shaking and shock with an air brake.

When the driver operates the brake handle, the brake force command unit 1 generates a brake force command value 2 and sends it to the air brake control device 3 and the chopper device control unit 4.

The main circuit of the armature chopper type electric vehicle includes an armature 5 of the main motor, a field 6, a chopper section 7 composed of a zyristor, etc., a flywheel diode 8, a filter capacitor 9. It is comprised of a filter reactor 10, a pantograph 11, a current detection device 112 that detects the traction motor current IA, a voltage detection device 13 that detects the armature voltage EM of the traction motor, and the like. The chopper device control section 4 has an actual brake force signal section 15 that calculates the regenerative braking force generated by the main motor at that time from the detected value 14 of the main motor current IA from the current detection device 12. A signal 16 is output.

The actual brake force signal 16 is sent back to the air brake force control bag number 3, and the value of the difference from the brake force command value 2, that is, the supplementary brake force command value 17, is input to the electro-pneumatic conversion valve 18, and the brake pressure of the supplementary air brake is inputted to the electro-pneumatic conversion valve 18. 19 is output. In this way, control is performed so that the total braking force of the regenerative braking force and the supplementary air braking force matches the braking force command value 2: Also, in the chopper device control section 4, the output 20 of the voltage detection device 13 is There is an armature voltage limiter circuit 21 to suppress the voltage generated by the armature to below the overhead line voltage. In the 9 range, the armature voltage limiter signal 22 is output.

The actual brake force signal 16 and the armature voltage limiter output 22 are subtracted from the brake force command value 2 (No. 1 is input to the phase control circuit, and this phase control circuit 23 sends a conductivity signal train to the chopper section The chopper section 7 is controlled so that the actual brake force signal 16 and the brake force command value 2 match within the limits of the armature voltage limiter.

Although it is not shown in Figure 1, when a skid occurs, multiple traction motors (usually 4 or 8) are controlled by a pair of chopper devices, so an imbalance in the terminal voltages of the multiple traction motors is detected. A skid detection device 25 is provided, and a skid detection signal 26 is input to the chopper device control section 4.
The conductivity is narrowed down by the conductivity narrowing pattern 28 of the conductivity narrowing pattern generating circuit 27 during sliding, and the armature current I
A is decreased to reduce regenerative braking force.

On the other hand, as shown in FIG. 2, the adhesion coefficient μ between the rail and the wheel tread has a property of decreasing as the speed increases due to its relationship with the speed ■. Therefore, when driving at high speeds, skidding is more likely to occur even when decelerating with the same brake force than when driving at low speeds, and the wheel treads are more likely to be flat. As shown in Figure 3, the brake force command value is set to a value corresponding to the adhesion coefficient μ shown in Figure 2 when driving at high speed, as shown in Figure 3. Conventionally, control methods have been used to reduce

In order to realize this control method, it was necessary to add the function of the speed pattern generator shown in FIG. 4 to the brake force command device shown in FIG. 1. That is, in FIG. 4, the speedometer generator 29, the τ conversion circuit 30, the speed pattern generation circuit 3
This was achieved by adding first class parts and circuits.

However, the speedometer generator attached to the axle for extracting the rotational speed of the wheel has mechanical parts and has a large number of parts such as a vehicle conversion circuit and a speed pattern generation circuit, so it is not reliable and economical.

<Object of the Invention> The present invention has been made in view of the above points, and is a highly reliable and economical method that prevents skidding by reducing the braking force in high speed ranges where the coefficient of adhesion is low than in low speed ranges. We provide brake control devices for electric vehicles.

<Summary of the Invention> The present invention detects the armature current while limiting the armature voltage generated during high-speed regenerative braking, and calculates the regenerative rake force actually generated from the detected armature current. In this system, the regenerative braking force by armature chopper control and the regenerative braking force supplementing this regenerative braking force are controlled according to the difference value by comparing the command value of the braking force. By adding control to limit the generated armature voltage to the calculated regenerative braking force that controls the braking force, the above object is achieved by reducing the air braking force during high-speed braking.

<Embodiments of the Invention> Examples of the present invention will be described below with reference to the drawings.

FIG. 5 is a diagram showing an embodiment of the present invention, in which the same parts as those of the conventional brake control device for an electric vehicle shown in FIG.

In FIG. 5, 30 is newly added in the present invention, and is the output 1 of the actual brake force calculation unit 15 of the chopper device control unit 4.
This is an adder that adds the output 22 of the armature voltage limiter circuit 21 to 6.

The operation of the embodiment of the present invention shown in FIG. 5 will be explained in the sixth section below.
This will be explained with reference to the figures.

In FIG. 6, (a) is the brake force command value 2 output from the brake force command device 1 shown in FIGS. 1 and 5, and (b)
(C) is the actual brake force signal output by the actual brake force calculation unit 15 shown in FIGS. 1 and 5, and (d) is the same 1 or more (a) in the armature voltage limiter signal output by the armature voltage limiter circuit 21 shown in FIGS. 1 and 5.
There are no differences between the conventional method and the present invention in (d). <e
) is output by the actual brake force calculation section 15 using the adder 30 newly added in the present invention, and is shown as a dotted line.C)
The brake force signal 33 for firm brake control is obtained by adding the armature voltage limiter signal 22 described in (d) and output from the armature voltage limiter circuit 21 to the actual brake force signal 16 described in (d), and is shown by a dotted line in (e). Compared to the conventional actual brake force No. 16 mentioned above, the value increases in the high speed range. Therefore, the supplementary braking force command value 17 output by the air brake control unit @3 will decrease in the high-speed range by the increased portion, and the supplementary braking force due to the air brake will be indicated by the solid line in Fig. 6(f). As shown, the supplementary braking force in the high speed range is lower than the conventional supplementary braking force shown by the dotted line.

The amount by which this braking force decreases increases as the speed increases, and the total braking force of the regenerative braking force and supplementary air braking force shown by the solid line in Fig. 6 (g) also differs from the conventional total braking force shown by the dotted line. will be a smaller value than
It is possible to prevent the occurrence of skidding at high speeds where the adhesive coefficient is low.

Although the adder is provided separately from the chopper device control section in this embodiment, it may be provided within the chopper device control section.

Furthermore, in the above embodiment, the output of the armature voltage limiter circuit is used to suppress the supplementary air braking force in the high speed range of the armature chopper method, but even in the case of the field chopper method, the supplementary air braking force is suppressed in the high speed range. The same effect can be achieved by using the output of the rectifier limiter circuit of the field chopper controller.

<Effects of the Invention> As explained above, according to the present invention, there is provided a device that performs particularly mechanical operation to reduce the braking force in the high speed range where the adhesion coefficient is low than in the low speed range to prevent the occurrence of skidding. Since there is no need to use a brake control system and fewer parts are used, a reliable and economical brake control system for electric vehicles can be obtained.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram of a conventional brake control device for an electric vehicle, Figures 2 and 3 are diagrams for explaining the technical background of the invention, Figure 4 is a diagram of a conventional speed pattern generator, and Figure 5 is a diagram of a conventional speed pattern generator. The figure is a circuit diagram showing an embodiment of the brake control device for an electric vehicle according to the present invention, and FIG. 6 is a diagram for explaining the operation of FIG. 5. 1... Brake force command device 3... Air brake control device 4... Chopper device control section 5... Main motor armature 7... Chopper section 12... Current detection Device 13... Voltage detector 15... Actual brake force calculation unit 21... Armature voltage limiter circuit 30... Adder (7317) Agent Patent attorney Kensuke Chika (and others) 1 person) Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] The regenerative braking force of the DC motor controlled by the armature chopper device and the brake control that supplements the regenerative braking force with the air braking force suppress the voltage generated by the armature in the high-speed regenerative braking and generate the regenerative braking force from the detected armature current. In a brake control system for an electric vehicle, the regenerative braking force and the air braking force are controlled according to the value of the difference between the actual braking force and the commanded braking force.
an adder that adds the output of the armature electric ratio limiter circuit that suppresses the voltage generated by the armature and the output of the actual brake calculation section that calculates the actual brake force, and outputs a signal that controls the air brake force. A brake control device for an electric vehicle characterized by: