JPS62281705A - Slip control method for electric rolling stock - Google Patents

Abstract

PURPOSE:To detect an accurate slip speed at all times, by obtaining the flux from the field flux characteristic of amotor in detecting the armature differential voltage and field current connected in series. CONSTITUTION:A voltage detector DCPT detects the occurrence of slip in detecting that the counter electromotive force of armatures A 1 and A 2 becomes unbalanced when the slip occurs. A slip detector 1 inputs the output DELTAE of DCPT and the field current IF from a current detector DCCT and calculates the field flux phi from the field flux characteristic of a motor and the input IF. Then an operation DELTAV=XDELTAE/phi is carried out to find the output DELTAV of a slip detector l. Ry an adder 3, subtraction of the output IP of a current pattern generator 2 and DELTAV is carried out and gives answer to a current control computing element 4. In this way, the accurate slip speed can be detected at all times.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for controlling the idling of an electric vehicle, and in particular, to improving the performance of idling control of a DC motor using chopper control input. Regarding.

[Conventional technology]

FIG. 3 shows an example of a slip control method using a conventional device disclosed in Japanese Unexamined Patent Publication No. 51-93005. PG in Figure 3
is the current collector, FL-FC is the filter circuit, accelerator and capacitor, person 1 and A2 are the armatures of the DC motor, Fl and F2 are the field windings of the DC motor, MSL is the smoothing reactor, and CH is the chopper. , D is a freewheel diode, R1 and R2 are voltage dividing resistors, DCPT is a voltage detector,
DCCT is a current detector, 2 is a current pattern generator, 3 is an adder, 4 is a current control calculator, 5 is a chopper phase shifter,
6 indicates an idle rotation detector.

Conventional devices usually utilize the fact that the armature difference voltage is generated almost in proportion to the idling speed to create a control system in which the adder 3 subtracts the pattern generated by the current pattern generator 2 by a value proportional to the DCPT output. By performing @, readhesion control] is performed. However, as a result of reducing the motor current, the armature voltage decreases, so the differential voltage for the same idling speed decreases, so there is a drawback that the idling speed cannot be accurately detected using this differential voltage.

[Problem that the invention seeks to solve]

In the above conventional technology, slipping is detected by the generation of armature differential voltage, and the current of the motor is reduced according to the value of the differential voltage to lower the generated torque and re-adhesion. 8, but by decreasing the electric motor current, the field 1!
There is no consideration given to the fact that the current decreases and the value of the armature differential voltage for the same slip speed becomes smaller, that is, the slip detection sensitivity decreases during readhesion control. There was a problem in that the idle speed could not be detected accurately.

An object of the present invention is to provide a method that always accurately detects the idling speed and performs idling control.

[Means for solving problems]

The above purpose is to detect the field current of the DC motor, calculate the field magnetic flux from the motor characteristics, and utilize the characteristic that the armature back electromotive force is proportional to the product of the field magnetic flux and the motor rotation speed. The difference voltage ΔE of the armatures connected in series and the field current IFt-
Detect the magnetic flux φ from the field magnetic flux characteristics of the motor, and calculate the idling speed vS as follows: VS=KXΔE/φ ・・・・・・・・・
...Achieved by finding (1).

Here K is a constant.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 1 is an idle rotation detector.

The t-light control of a DC motor using a chopper is a well-known technique described in many papers and the like, and a description of its operation will be omitted here.

The resistance values of R1 and R2 are selected to be equal, and the DCPT detects that the back electromotive force of A1 and A2 becomes unbalanced when a slip occurs, thereby detecting the occurrence of a slip.

The idling detector 1 inputs the output ΔE of the DCFT and the output IP of the DCCT, and calculates the field magnetic flux φ from the field magnetic flux characteristics of the motor and the input IF'. The specific calculation method is based on the input IP
This can be obtained by creating in advance a converter that obtains an output φ for the IP, and automatically converting the output from IP to φ. Next, the output Δ■ of the slip detector 1 is obtained by calculating (ΔV=KXΔE/φ). The output of the current pattern generator 2 is set as IP, and the adder 3 subtracts (IP-ΔV), and the output is input to the current control calculator 4. The current control calculator 4 sets 1! so that the subtracted pattern and the output of the DCCT match. Perform flow control tMJ.

FIG. 2 shows voltage/current characteristics for each area according to FIG. 1 of the embodiment.

When idling occurs, back electromotive force FAI/EA2 of A1/A2
A difference is generated in the DCPT, and the DCPT detects this difference ΔEt- to reduce the motor current M. At this time, since the absolute value of the armature voltage decreases, the DCPT output ΔE is no longer proportional to the idling speed ■s. Therefore, the idling speed vS can be accurately detected by performing calculations using the method shown in FIG. 1 from the DCCT output IF.

〔Effect of the invention〕

According to the present invention, even if the armature back electromotive force decreases in the process of performing readhesion control during idling, the idling speed can always be accurately detected. Even if it is difficult to mechanically detect the speed, it is possible to indirectly and accurately detect the idle speed using a simple method using voltage and current detection.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an embodiment of the present invention, and FIG. 2 is a circuit diagram of an embodiment of the present invention. Current Characteristics, FIG. 3 is a circuit diagram showing an example of the conventional technology. PG... Current collector.

Claims (1)

[Claims] 1. A plurality of armatures of a DC motor connected in series, a chopper that controls the current flowing through the armatures, and a voltage detection that detects the difference in back electromotive force between the armatures. In the idling control device for a DC motor that limits the current flowing through the armature according to the difference between the counter electromotive force and the back electromotive force, the A method for controlling the slippage of an electric vehicle, comprising correcting the difference in the back electromotive force.