RU2706709C1 - Apparatus for testing transformers and reactors - Google Patents

Abstract

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering and is used in transformer plants. Invention comprises network transformer (1) connected to converter (2) of three-phase mains voltage into alternating voltage, controlled by frequency and value by voltage inverter, equipped with control unit (9), output transformer (5, 6), output terminals (4) of alternating current. Novelty is switch (3), which central lead is connected to converter (2), first extreme terminal is connected to output transformer (4, 5), and the second one – to DC terminal (7), and the second DC control unit (10) is introduced, outputs of control units are connected to extreme outputs of contact-block (11) of switch (3), which central lead is connected to converter control input. This achieves a new function – obtaining direct current at output, which is required for removal of reactor reactive-reactor characteristics.

EFFECT: broader functional capabilities.

1 cl, 2 dwg

Description

The invention relates to electrical engineering and is used in transformer plants. The well-known [1] circuit of a device for a similar purpose, containing a frequency converter, connected to an output three-phase transformer by an output. The disadvantage of such a device is its great complexity due to the need to use a six-phase converter. In addition, in single-phase mode, the output power is reduced by 2/3.

The closest in technical essence and the achieved results to the first option is the installation of / 2 / and reactors. The disadvantage of this device is the relatively low functionality, since such a circuit is adapted only for testing with alternating current. Meanwhile, for testing the reactors, an adjustable direct current is required to take the web-ampere characteristic.

The technical result of the proposal is the expansion of functionality.

The technical result is achieved due to the fact that the installation contains a switch, the central terminal of which is connected to the output of the converter, the first extreme terminal is connected to the output transformer, and the second to the DC terminal and the second DC control unit is inserted, the outputs of the control units are connected to the extreme terminals of the block contact switch, the Central output of which is connected to the control input of the Converter.

The technical result is additionally achieved due to the fact that the switch is made of three-pole, with the combined second extreme conclusions, the output transformer and the converter are made of three-phase.

In FIG. 1 shows a single-line installation diagram containing a network transformer 1 and a converter 2 for converting a three-phase network voltage to a voltage, adjustable in frequency and amplitude. A converter 2 is connected by an output to switch 3. There are AC output terminals 4 and a transformer with windings 5 and 6, DC terminals 7, 8, AC and DC units 9, 10, respectively, and a switching block contact 11. In FIG. 2 shows a converter circuit 2 comprising a three-phase diode bridge 12, a capacitor 13, a single-phase diode bridge 14, a bridge of lockable thyristors or transistors 15-18. The first mode of operation of the installation. An AC test load is connected to terminals 4. The switch 3 attaches the transformer 4, 5 to the converter, and the block contact 11 AC unit 9, which sets the necessary frequency and magnitude of the alternating current, forming the control signals of transistors 15-18. The second mode is direct current. A test reactor is connected to terminals 7, 8, in which it is necessary to increase the required value of direct current, and then short-circuit it, providing a smooth free-fall current to zero / 3 /. In this case, the contacts 3, 11 are installed in the opposite direction. The transformer 4, 5 and unit 9 are turned off. Block 10 gives a signal for a long (until the current drops to zero) thyristor 15 is turned on, and thyristor 18 is turned on only at the stage of increasing current in the load (the tested reactor) to the required value. In the second recession period, the current 18 is turned off and the load current is closed through the thyristor 18 and one of the bridge diodes 14. Both modes can be provided in both single-phase and three-phase versions 2, 3, 4, 5. Thus, the installation very easily provides a transition from one mode to another, providing wider functionality.

Information sources:

1. Patent for utility model of the Russian Federation No. 142928, cl. G0lR 31/12, 06/17/2013

2. Patent for utility model of the Russian Federation No. 119544, class. Н02М 5/451, Н02М 5, December 4, 2012

3. IEC 60076-6-2007 standard, b.

Claims (2)

1. Installation for testing transformers and reactors, comprising a network transformer, which is connected via an output to a converter of three-phase mains voltage to alternating voltage, including an inverter for regulating voltage in frequency and magnitude, equipped with a control unit, an output transformer, output terminals, characterized in that the installation contains a switch, the central terminal of which is connected to the output of the converter, the first extreme terminal is connected to the output transformer, and the second to the constant terminal of the current, and the second DC control unit is introduced, the outputs of the control units are connected to the extreme terminals of the switch contact block, the central terminal of which is connected to the control input of the converter. 2. Installation for testing transformers and reactors according to claim 1, characterized in that the switch is made tri-pole with the combined second extreme conclusions, the output transformer and the converter are made three-phase.

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