CONTROL DEVICE FOR HIGH-VOLTAGE VACUUM TRACTION SWITCH WITH ALTERNATING CURRENT

Abstract

This utility model relates to electrical engineering, specifically to control devices for high-voltage circuit breakers, disconnectors, and other switching devices. The control device can be used to control high-voltage circuit breakers used on traction rolling stock. The technical result consists of maintaining the key technical characteristics of the high-voltage circuit breaker within an operating range of 0.7 to 1.25 times the nominal control circuit voltage when switching electrical circuits under railway operating conditions.The high-voltage switch control device comprises an output voltage stabilization and boosting unit, an output voltage stabilization unit for the actuator circuit, a control unit, controlled contacts and switching contacts, an optothyristor in the discharge circuit (during the off-cycle), an optothyristor in the discharge circuit (during the on-cycle), an additional resistor, and a capacitor block. 4 sec. f-ly, 5 fig.

Description

[0001] This utility model relates to electrical engineering, specifically to control devices for high-voltage circuit breakers, disconnectors, and other switching devices. The control device can be used to control high-voltage circuit breakers used on traction railway rolling stock.

[0002] A high-voltage circuit breaker control device is known (patent SU 1332405 A1 dated August 23, 1987). This control device comprises several low-voltage terminals for series connection with the terminals of the control coil of the high-voltage circuit breaker's electromagnetic drive, the main (power) thyristor, and the terminals of the DC power supply. To reduce switching losses and improve response time, block-capacitor commutation is implemented, connected via an antiparallel-connected auxiliary thyristor and a diode. To reduce power consumption, a piezoelectric sensor and a zener diode are included in the device, connected to the control junction of the auxiliary thyristor. The piezoelectric sensor is located in the gap between the armature and the core of the electromagnetic drive, providing control by converting mechanical forces into an electrical signal. The zener diode stabilizes the voltage at the control junction.

[0003] The proposed solution has the following disadvantages:

[0004] the complexity of integrating a piezoelectric sensor into the design of an electromagnetic drive (limits the variability of drive designs);

[0005] The piezoelectric sensor installed in the gap is subject to wear, which limits the mechanical wear resistance of the high-voltage circuit breaker and reduces the intervals between repairs and the service life of the circuit breaker;

[0006] lack of galvanic isolation of the control circuit from the power control thyristors;

[0007] Limited adaptability, for use in high-voltage switches operated on traction railway rolling stock, due to the range of supply voltage changes and operating modes.

[0008] The closest device is a high-voltage circuit breaker control device (SU 1381617 A1 dated March 15, 1988). This high-voltage circuit breaker control device includes an induction-dynamic drive with a controlled coil, to which two storage capacitors are connected via thyristors, controlled by a block with a changeover contact for series or parallel switching of the thyristors. To expand the range of application and improve the device's reliability, additional elements have been incorporated: a delay diode and two quenching blocks. The quenching blocks have terminals connected to the thyristor anodes, while their second terminals are combined and connected to the anode of a special delay diode and the cathode of an additional thyristor. The control electrode and cathode of the additional thyristor described above are connected to the delay block, which ensures effective quenching.

[0009] The proposed solution has the following disadvantages:

[0010] It is impossible to adjust (reduce) the switch-off time of the circuit breaker drive during automatic reclosing, where after switching on to a short circuit it is necessary to quickly switch off the circuit breaker in the electrical network.

[0011] lack of galvanic isolation of the control circuit from the power control thyristors;

[0012] Limited adaptability, for use in high-voltage switches operated on traction railway rolling stock, due to the range of supply voltage changes and operating modes.

[0013] The tasks that the utility model can solve are:

[0014] the ability to reduce the high-voltage circuit breaker's own tripping time;

[0015] Galvanically isolate the switch control unit from the control power circuit;

[0016] maintain the time and speed characteristics of the high-voltage switch in the range of supply voltage values;

[0017] Creation of a unified control device for a series of switches with two-winding electromagnetic drives used on traction railway rolling stock.

[0018] The technical result is an increase in the speed, reliability and versatility of control of a high-voltage switch by reducing the inherent shutdown time, ensuring galvanic isolation of control circuits, maintaining characteristics in an extended range of supply voltage and unification for a series of switches with an electromagnetic drive.

[0019] The technical result is achieved in that the high-voltage switch consists of the following main components:

[0020] contact system (1) (moving and fixed), which performs switching of the main (power) circuit;

[0021] an electromagnetic drive (2) designed to control a contact system and containing a magnetic circuit (3), an anchor (4), a holding winding (5) and a starting winding (6) (which also functions as a trip winding), a contact block (7) kinematically connected to the anchor (4) of the electromagnetic drive (2), contains normally closed (7.1) and normally open (7.2) contacts for switching control circuits depending on the position of the electromagnetic drive (2);

[0022] control module (8) containing the main components of the control device, namely the output voltage stabilization and boosting unit (9); the output voltage stabilization unit (10) of the executive component circuit; control unit (11) (controlling signals during the on and off cycles); contactors (12), (13) with controlled contacts (12.1), (12.2) and (13.1), respectively, an optothyristor (14) in the discharge circuit (during the off cycle); an optothyristor (15) in the discharge circuit (during the on cycle); resistor (16); capacitor block (17), (18).

[0023] In this case, the connection of the circuits of the contactor control coils (12), (13), the holding winding (5) with the blocks (10), (11) is performed as follows:

[0024] one terminal of the contactor control coil (12) is connected to the output of the output voltage stabilization unit (10), and the second terminal of this coil is connected to the common output of the output voltage stabilization unit (10) via the normally closed contact (7.1) of the contact block (7); the first terminals of the holding winding (5) and the contactor control coil (13) are connected to the control output of the control unit (11); the second terminals of the holding winding (5) and the contactor control coil (13) are connected to the common output of the output voltage stabilization unit (10), wherein the second terminal of the holding winding (5) is connected to the common output via the normally open contact (7.2) of the contact block (7).

[0025] The utility model is explained with graphic materials.

[0026] Fig. 1 shows a general view of the high-voltage switch under consideration;

[0027] Fig. 2 shows a bottom view of the high-voltage switch in question;

[0028] Fig. 3 - shows the electromagnetic drive device;

[0029] Fig. 4 - shows the structure of the control module;

[0030] Fig. 5 shows a schematic diagram of the utility model.

[0031] The high voltage switch control device operates as follows.

[0032] In the static state (standby mode), in the presence of DC supply voltage at the input of the output voltage stabilization units (9), (10) and the control unit (11) (Fig. 5), the switch control device goes into the waiting mode for a command to turn on the switch at the input of the control unit (11). In this mode, the control voltage from the output voltage stabilization unit (10) appears at the terminals of the contactor control coil (12) through the normally closed contact (7.1), the controlled contact (12.1), which is in the closed state, and the contact (12.2), which is in the open state, change their closed and open states to the opposite (the controlled contact (12.1) is open, the controlled contact (12.2) is closed), which prepares the control circuit of the starting winding (6) of the electromagnetic drive (2) to perform the switch closing cycle, and the open state of the controlled contact (12.1) eliminates the possibility of applying reverse voltage to the terminals of the starting winding (6) in the event of an internal breakdown of the optothyristor (14). The capacitor blocks (17), (18) (storage) are charged through the current-limiting resistor (16) by the increased voltage generated by the block (9). The optothyristors (14) and (15) are in the closed state.

[0033] When an external command to turn on is received, the control unit (11) simultaneously generates the following signals:

[0034] closes the power supply circuit of the contactor control coil (13), which opens the normally closed contact (13.1), interrupting the charging circuit of the capacitor block (18), isolating it from the power source;

[0035] gives a control signal (to open) the optothyristor (15);

[0036] closes the power supply circuit of the holding winding (5) of the electromagnetic drive (2), supplying voltage to it.

[0037] The open optothyristor (15) connects the pre-charged capacitor block (18) to the starting winding (6) through the closed controlled contact (12.2). The discharge current flowing through the starting winding (6) creates an electromagnetic force that moves the armature (4) (Fig. 2, 3) of the electromagnetic drive (2), which, in turn, moves the movable contact system (1) (Fig. 1) of the switch to the closed position, whereby the contact (7.2), kinematically connected to the movable part of the electromagnetic drive (2), closes, closing the power supply circuit of the holding winding (5). After completion of the switching-on cycle and its latching, the power supplied to the holding winding (5) at the beginning of the switching-on cycle holds the electromagnetic drive (2) and the contact system (1) of the switch in the closed position. At the end of the switching-on cycle, the contact (7.1), kinematically connected with the moving part of the electromagnetic drive (2), breaks the power supply circuit of the contactor control coil (12), the controlled contact (12.1) closes, and the contact (12.2) opens. The open controlled contact (12.2) in the switching circuit prevents the switch from operating during the switching-off cycle in the event of an internal breakdown of the optothyristor (15).

[0038] When an external command to turn off is received, the control unit (11) simultaneously sends an unlocking control signal to the optothyristor (14), opens the power supply circuit of the contactor control coil (13) and the holding winding (5). The open optothyristor (14) connects the capacitor block (17) to the starting winding (6) through the closed contact (12.1) with reverse (relative to the switching-on cycle) polarity, creating a current pulse that returns the electromagnetic drive (2) and the contact system (1) of the circuit breaker to the open (disconnected) position, the contact (7.2) kinematically connected to the movable part of the electromagnetic drive opens.

[0039] Increasing the reliability and expanding the scope of application of a high-voltage switch when switching electrical circuits under operating conditions on railway transport is achieved through: the use of stabilization units in the control device, which allows maintaining the main technical characteristics of the switch in the operating range of values ​​from 0.7 to 1.25 of the nominal value of the control circuit voltage;

[0040] The use of an additional capacitor block and a circuit that allows for the application of reverse polarity voltage to the starting winding upon a trip signal, thereby reducing the breaker's own tripping time by half and increasing reliability in operating modes that require immediate disconnection from the electrical network; the use of optothyristors as a control power key, which allows for a simplified breaker control unit and thereby interconnects control circuits of different potentials; to prevent false re-triggeration in the event of an internal breakdown of one of the optothyristors, a controlled contact is connected in series with it in the circuit; in standby mode, after an on / off cycle, this contact physically breaks the discharge circuits.

Claims

1. A high-voltage switch control device comprising a control module and an electromagnetic drive with starting and holding windings, characterized in that the control module contains a unit for stabilizing and increasing the output voltage (9), a unit for stabilizing the output voltage of the circuit of executive components (10), two units of storage capacitors (17, 18), a current-limiting resistor (16), two optothyristors (14, 15), two contactor control coils (12, 13), as well as a contact unit with normally closed (7.1) and normally open (7.2) contacts, kinematically connected with the anchor of the electromagnetic drive, wherein the output of the voltage stabilization and boosting unit (9) is connected through the current-limiting resistor (16) to the storage capacitor blocks (17, 18) for charging them, the optothyristor (14), operating on the switch-on cycle in the discharge circuit, is connected between the capacitor block (17), used on the switch-on cycle, and the starting winding (6), the optothyristor (15), operating on the switch-off cycle in the discharge circuit, is connected between the capacitor block (18), used on the switch-off cycle, and the starting winding (6), the control inputs of the optothyristors (14, 15) and the control coil of the contactor (13) are connected to the outputs of the control block (11), and controlled contacts (12.1) are also introduced (12.2), which protect the discharge circuits from abnormal operations and are connected accordingly in series in the optothyristor circuits - between the optothyristors (14, 15) and the starting winding 6, one of the terminals of the contactor control coil (12) is connected to the output of the voltage stabilization unit of the executive component circuit (10), and the second terminal of the contactor control coil (12) is connected through the normally closed contact (7.1) of the contact block (7) to the common output of the voltage stabilization unit (10), the first terminals of the holding winding (5) and the contactor control coil (13) are connected to the output of the control unit (11), and the second terminals are connected to the common output of the output voltage stabilization unit of the executive component circuit (10), wherein the terminal of the holding winding (5) is connected through the normally open contact (7.1) of the contact block (7).

2. The device according to paragraph 1, characterized in that optothyristors (14, 15) are used to switch the power control circuits.

3. The device according to paragraph 1, characterized in that increased voltage from the voltage stabilization and booster unit (9) is used to charge the block of storage capacitors (17, 18).

4. The device according to paragraph 1, characterized in that during the shutdown cycle, a voltage of reverse polarity from the block of storage capacitors (17) is applied to the terminals of the starting winding (6).

5. The device according to paragraph 1, characterized in that in order to prevent false re-triggering in the event of an internal breakdown of one of the optothyristors (14, 15) in the circuit, a controlled contact (12.1, 12.2) is connected in series with it, which, in standby mode after an on or off cycle, physically breaks the discharge circuits.

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