JPH01321802A - Controller for electric rolling stock - Google Patents

Abstract

PURPOSE:To enable smooth transition from the constant current control zone to the current limit step control zone by transiting a motor to field weakening control when the control phase angle of each semiconductor switch element in a group of control rectifier goes to zero and the current of a DC motor drops below a set value. CONSTITUTION:A comparator 23 provides a difference signal between a current set value 1p corresponding to a notch signal fed from a trunk controller 20 and the current Ia of DC motors 5, 6 to a regulator 24. The regulator 24 controls semiconductor switching elements 13, 14 according to an input signal. When a field weakening command is provided, the current set value 1p exceeds over the current Ia and when all the control phase angle of all semiconductor switching elements 13, 14 in the control rectifier groups 1U-4U is commanded to zero, a signal is outputted from an AND gate 30. Consequently, the contact 33a of a contactor/controller 33 is closed and a field weakening resistor 34 is inserted.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an electric vehicle control device, and in particular, to a control device for controlling an electric vehicle, and particularly to a control device for controlling a main motor of a rectifier phase control type AC electric vehicle. The present invention relates to an electric vehicle control device suitable for combined use.

[Conventional technology]

Electric cars, especially railway cars, have multiple power units, and among them, AC electric cars apply an AC voltage to the overhead wires and are equipped with a control rectifier.

A method that replaces alternating current with direct current and drives it in addition to a direct current motor is often used.

Fig. 2 shows a block diagram of the main circuit of such a conventional technology.The primary winding of the main transformer 3 is connected to the AC power supply 1, and the secondary winding is divided into a plurality of parts, each of which is equipped with a semiconductor switching element (
Control rectifiers IU to 4U configured as a bridge with thyristor) 13.14 and diodes 11.12 are connected, and on their DC side, smoothing reactor 1o, DC motor 5.6, and field windings 7, 8 are connected. The main circuit is constructed by connecting the DC circuits. In such a main circuit, by controlling the control phase angle (α) of the semiconductor switching elements 13°14 in the control rectifier groups IU to 4U,
It is well known that 6 can be controlled.

Incidentally, acceleration control in an AC electric vehicle equipped with such a main circuit has been performed as follows. The receiving relay circuit 21 receives a notch command from the master controller 2o,
A current value corresponding to the notch command is supplied from the current setting (pattern) circuit 22 to the comparator 23. On the other hand, the DC motor 5
, 6 is detected by a DCCT (direct current alternating current converter) 9, and the current value is given to a comparator 23 via a feedback device 25. A signal corresponding to the deviation between the two types of flow values is given from the comparator 23 to the regulator 24, and the regulator 24 passes through the phase shifter 26 to the semiconductor switching elements 13 and 14.
The electric vehicle accelerates by gradually opening the control phase angle from π toward zero degrees, increasing the DC output voltage, and controlling the acceleration current to a constant value. Here, the order in which the semiconductor switching elements 13.14 are controlled is such that the control phase angle of the semiconductor switching elements 13.14 of the first stage (IU) changes from π to zero degrees, and then the 2
The control phase angle of the semiconductor switching elements 13 and 14 of stage (2U) is controlled from π to zero degrees.

Thereafter, the phase angles of the semiconductor switching elements 13 and 14 of the third stage (3U) and fourth stage (4U) are sequentially controlled from π to 0 degrees. In the above order, all semiconductor switching elements 13.
The phase angle of 14 is zero degrees (fully open).

FIG. 3 shows a characteristic diagram of the relationship between current and speed during acceleration according to the prior art.

Literature related to this type of control device includes, for example, ``Science of Electric Vehicles,'' published in November 1960, page 20, and ``Science of Electric Vehicles'', published in August 1960, pages 32-33.

[Problem to be solved by the invention]

In the above conventional technology, the DC motors 5 and 6 are completely magnetized (100%
It is intended to be used in the field (magnetic field).

However, one possible means of increasing the speed of an electric vehicle is to switch the DC motor from the full field range to notch advance control using current limit value control and use it in the field weakening range.

However, the above-mentioned conventional technology is inconvenient because it does not have a function to switch from constant current control in the entire field region to current limit value control to shift to the field weakening region.

The purpose of the present invention is to solve the above-mentioned inconveniences in the prior art,
The object of the present invention is to provide an electric vehicle control device having both constant current control and current limit value control functions.

[Means to solve the problem]

The above object is to provide circuit means for detecting that the control phase angles of the semiconductor switching elements in the control rectifier group have all reached zero degrees (fully open) and that the current flowing through the armature of the traction motor has become smaller than a set value; The configuration includes circuit means for outputting a command signal to start field weakening control when these two conditions are satisfied, and circuit means for shifting the main motor to field weakening control in response to this command signal. This is achieved by

[Effect]

A signal that detects that the control phase angles of each semiconductor switching element in the control rectifier group have all reached zero degrees and a signal that detects that the current flowing through the armature of the DC motor has become smaller than the set value are logically combined. By controlling the opening and closing of the contactor for current limit value control by a relay that is input to a product circuit and activated by the output signal of this AND circuit, a smooth transition from a constant current control area to a current limit value advancement control area is achieved. I can do it.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 4. The difference between the block diagram of the embodiment shown in FIG. 1 and the conventional example shown in FIG. 2 is that the field winding RIA7.
A field weakening resistor 34 and a field weakening contactor group 33a to 33c for controlling the insertion of the field weakening resistor 34 are located in the DC circuit in parallel with the field weakening resistor 8, and a contact for controlling the opening and closing of these contactor groups 33a to 33c. The condition is that the controller (control coil) 33 and the semiconductor switching elements 13.14 of the control rectifier groups IU to 4U are all at zero temperature, and the set value (current limit) of the current flowing through the armature of the DC motor 5.6 The two conditions of the smaller condition (value) are that an AND circuit 30 that receives input and a relay 31 that operates with its output are added.

Next, an explanation will be given of the operation when the DC motor shifts from constant current control to current limit value control. In FIG. 1, the weak field notch signal is transmitted from the main controller 20 to the contactor controller (control coil) 33 via the normally open contact 31a of the relay 31.
given to.

On the other hand, the current Ia flowing through the armatures of the DC motors 5 and 6 is
The current value is detected by the DCCT 9 and given to the comparator 23 via the feedback device 25.

In the comparator 23, the set value (
The pattern value knee corresponding to the current limit value) is compared with the above I&, and if the condition Ia<Ip is satisfied, a signal is sent to one input of the AND circuit 30. Further, in the regulator 24,
It is detected that the control phase angles of the semiconductor switching elements 13 and 14 of the control rectifier groups IU to 4U are all commanded to zero degrees, and this detection signal is input to the other input of the AND circuit 30.

When these two conditions are met and input, AND circuit 3
The level of the 0 output signal becomes "1", the relay 31 is activated, and its normally open contact 31a is closed.

This barrier, the contactor controller (control coil) 33 is excited,
In conjunction with this, the field weakening contactor 33a is closed, and the field weakening resistor 34 is inserted in parallel to the field windings 7 and 8.
It enters a state of field weakening operation using current limit value control.

FIG. 4 shows a characteristic diagram of the relationship between current and speed according to this embodiment. In FIG. 4, characteristic lines 1 to 4 are constant current control regions where the accelerating current is constant, which is the same as in the prior art. Characteristic line 5~
7 is the current limit value advancement control region by field weakening control.

As mentioned above, at the characteristic line 4, the semiconductor switching element 13
．． When all the phase angles of 14 become zero degrees (fully open) and the armature current further drops to the current limit value (IP), relay 3
1 (FIG. 1) is activated, and the closing of the contact 31a closes the interlocking contactor 33a of the contactor controller 33, and the field weakening resistor 34 is inserted. As a result, in FIG. 4, the characteristic line progresses from characteristic i4 to characteristic line 5. Thereafter, similarly, when the armature current drops to the current limit value 1p,
The contactor controller 33 operates to control the contactors 33b and 33c.
are sequentially closed, and characteristic line 5 to characteristic line 6. It will progress to characteristic line 7 one after another.

In the embodiment shown in FIG. 1, the number of controlled rectifiers is four, and the number of semiconductor switching elements in each controlled rectifier is two. However, these numbers may be larger or smaller. could be. Further, although the embodiment shown in FIG. 1 shows a case where there are two DC motors and one field control circuit, the number may be larger or smaller. The present invention can produce similar effects when applied to these various combinations and operated in the same manner as in the embodiments.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to smoothly transition from the constant current control region of the DC motor to the current limit step-up control region, so that field weakening operation of the DC motor, which is necessary for increasing speed, for example, can be easily performed. As a result, this was not necessary in the case of the prior art. There is no need to increase the number of control rectifiers or increase the secondary voltage of the main transformer to increase speed, making it possible to achieve higher speeds at low cost.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a block diagram of a conventional example, FIG. 3 is a characteristic diagram of the relationship between current and speed in the conventional example, and FIG. FIG. 4 is a characteristic diagram of the relationship between current and speed in the case of the illustrated embodiment. 1... AC power supply, 3... Main transformer, 5, 6... DC motor, 7, 8... Field winding, 9... DCCT,
11゜12...Diode, 13.14...Semiconductor switching element, 20...Main controller, 21...Reception relay circuit, 22...Current setting circuit, 23...Comparator,
24...Adjuster. 25...Returner, 26...Phase shifter, 31...Relay, Figure 1 and Figure 2

Claims (1)

[Claims] 1. A main transformer having a secondary winding divided into multiple parts, a circuit that controls the voltage applied to the main motor by controlling the phase of semiconductor switching elements in a control rectifier connected to each secondary winding, and In a controlled rectifier phase control type AC electric vehicle that is equipped with a circuit that feedback controls the accelerating current of the electric motor to a constant value,
circuit means for detecting that the control phase angles of the semiconductor switching elements in the control rectifier group have all reached zero degrees (fully open) and that the current flowing through the armature of the traction motor has become smaller than a set value; An electric vehicle comprising: circuit means for outputting a command signal to start field weakening control when two conditions are met; and circuit means for shifting the main motor to field weakening control in response to the command signal. Control device.