CN219351276U

CN219351276U - Starting current suppression device for high-capacity series resonance voltage-withstanding equipment

Info

Publication number: CN219351276U
Application number: CN202223557992.7U
Authority: CN
Inventors: 黎海凡; 谢雨轩
Original assignee: China Yangtze Power Co Ltd
Current assignee: China Yangtze Power Co Ltd
Priority date: 2022-12-30
Filing date: 2022-12-30
Publication date: 2023-07-14
Anticipated expiration: 2032-12-30

Abstract

The utility model discloses a starting current suppression device of high-capacity series resonance voltage-withstand equipment, which comprises a power switch cabinet and a voltage regulator; a breaker is arranged in the switch cabinet; the suppression device body is connected between the power switch cabinet and the voltage regulator; the suppression device body comprises an inductance coil L, an alternating current contactor KM and a time relay KT; the inductance coil L is connected in series on a line between the circuit breaker and the voltage regulator input, and the normally open contact of the alternating current contactor KM is connected with the inductance coil L in parallel to form an isolation bypass. The device can restrain the large excitation surge current generated in the moment of switching on the voltage regulator, reduce the switching-on times, improve the switching-on success rate, and can automatically exit operation after the starting is successful, so that the follow-up test is not affected.

Description

Starting current suppression device for high-capacity series resonance voltage-withstanding equipment

Technical Field

The utility model belongs to the technical field of stator alternating current withstand voltage tests of generators, and particularly relates to a starting current suppression device of high-capacity series resonance withstand voltage equipment.

Background

The series resonance voltage-withstand device is mainly used for stator alternating current voltage-withstand test of a generator, as the capacity of the generator increases, the capacitance of a stator winding to the ground increases, the inductance in a loop of the series resonance device also needs to increase, so that larger excitation surge current (8-10 times of rated current of a power switch to the maximum) can be generated when high-capacity series resonance voltage-withstand equipment is switched on, a test field voltage regulator is difficult to switch on, the switching-on success rate is less than 30%, and the upper-level 400V power distribution cabinet is easy to trip. If the quick-break release is to be prevented from tripping due to large excitation surge current, the current setting value of the circuit breaker in the power switch cabinet must be larger than the maximum excitation surge current of the voltage regulator to ensure that the circuit breaker can be switched on stably, but the capacity of the circuit breaker in the current field power switch cabinet cannot meet the test requirement; therefore, there is a need to design a starting current suppressing device for a high-capacity series resonance withstand voltage apparatus to solve the above-mentioned problems.

Disclosure of Invention

The utility model aims to solve the technical problem of providing a starting current suppression device for high-capacity series resonance voltage-withstand equipment, which can suppress large excitation surge current generated in the moment of switching on a voltage regulator, reduce switching on times, improve switching on success rate, and can automatically exit operation after the starting is successful without influencing the follow-up test.

In order to achieve the technical effects, the technical scheme adopted by the utility model is as follows: a starting current suppression device of high-capacity series resonance voltage-withstand equipment comprises a power switch cabinet and a voltage regulator; a breaker is arranged in the switch cabinet; the suppression device body is connected between the power switch cabinet and the voltage regulator; the suppression device body comprises an inductance coil L, an alternating current contactor KM and a time relay KT; the inductance coil L is connected in series on a line between the circuit breaker and the voltage regulator input, and the normally open contact of the alternating current contactor KM is connected with the inductance coil L in parallel to form an isolation bypass.

Preferably, an alternating-current contactor KM closing coil is connected in series with an auxiliary contact of a time relay KT, and two ends A1 and C1 of a series circuit are connected to a breaker output power supply 380V.

Preferably, the closing coil of the time relay KT is connected in series with the auxiliary normally open contact QF2 of the breaker, and two ends L, N of the series circuit are connected to the power transformer 220V.

The starting current suppression device for the high-capacity series resonance voltage-resistant equipment has the following beneficial effects:

1, stable performance, safety and reliability: the starting current restraining device ensures the switching-on success rate of the field voltage regulator, limits the excitation surge current to a reasonable range, enables the switching-on success rate to reach 100%, reduces switching-on times, and avoids damage to overhaul power supply cabinets and test equipment;

2, intelligence is convenient: the self-provided delay setting function is realized, the restraining device participates in the loop only at the moment of closing, the circuit is automatically short-circuited after being delayed and set by the time relay after closing, and the starting current restraining device automatically exits the loop;

3, the application range is wide. The universality is strong: the starting current suppression device is not only applied to the closing process of the high-capacity voltage regulator, but also can be used for solving the problem of no-load closing of the high-capacity single-phase or three-phase exciting transformer.

Drawings

The utility model is further illustrated by the following examples in conjunction with the accompanying drawings:

FIG. 1 is a schematic circuit diagram of the present utility model;

FIG. 2 is a schematic diagram of the circuit wiring in the present utility model;

FIG. 3 is a diagram showing the construction of an AC withstand voltage test in the background of the utility model;

in the figure: the power supply comprises a switch cabinet 1, a circuit breaker 11, a voltage regulator 2, a time relay auxiliary contact KT1, an alternating current contactor normally open contact KM1, a circuit breaker auxiliary normally open contact QF2 and an inductor L.

Detailed Description

As shown in fig. 1-2, a starting current suppression device of a high-capacity series resonance voltage-withstand device comprises a power switch cabinet 1 and a voltage regulator 2; a breaker 11 is arranged in the switch cabinet 1; the suppression device body is connected between the power switch cabinet 1 and the voltage regulator 2; the suppression device body comprises an inductance coil L, an alternating current contactor KM and a time relay KT; the inductance coil L is connected in series on a line between the breaker 11 and the input of the voltage regulator 2, and the normally open contact of the alternating current contactor KM is connected in parallel with the inductance coil L to form an isolation bypass.

Preferably, the switching-on coil of the alternating current contactor KM is connected in series with an auxiliary contact of the time relay KT, and two ends A1 and C1 of the series circuit are connected to the output power supply 380V of the circuit breaker 11.

Preferably, the closing coil of the time relay KT is connected in series with the auxiliary normally open contact QF2 of the circuit breaker 11, and two ends L, N of the series circuit are connected to the power transformer 220V.

Fig. 3 is a schematic diagram of an ac withstand voltage test.

The working principle of the starting current suppression device of the high-capacity series resonance voltage-resistant equipment is as follows:

closing the breaker 11, wherein an inductance coil L is connected in series to a load loop of the switch cabinet to form a loop with an input coil of the voltage regulator, and the current of the loop is limited in the setting range of the breaker 11 due to the existence of the inductance coil, so that the breaker 11 is not tripped; after closing, an auxiliary normally open point QF2 of the breaker 11 is closed, so that a time relay KT is electrified, after the time relay delays and sets, an auxiliary contact KT1 of the time relay is electrified, and a closing coil of an alternating current contact KM is electrified, so that the normally open contact KM1 of the alternating current contactor is closed, a bypass of a current-limiting coil L is isolated, and the current-limiting coil L does not work continuously; at that time, current in the main loop can pass through the KM contactor, the current limiting coil L does not work continuously, and the follow-up resonance withstand voltage test work is not influenced.

The foregoing embodiments are merely preferred embodiments of the present utility model, and should not be construed as limiting the present utility model, and the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without collision. The protection scope of the present utility model is defined by the claims, and the protection scope includes equivalent alternatives to the technical features of the claims. I.e., equivalent replacement modifications within the scope of this utility model are also within the scope of the utility model.

Claims

1. A starting current suppression device of high-capacity series resonance voltage-withstand equipment comprises a power switch cabinet (1) and a voltage regulator (2); a circuit breaker (11) is arranged in the power switch cabinet (1); the method is characterized in that: the suppression device body is connected between the power switch cabinet (1) and the voltage regulator (2); the suppression device body comprises an inductance coil L, an alternating current contactor KM and a time relay KT; the inductance coil L is connected in series on a line between the circuit breaker (11) and the input of the voltage regulator (2), and the normally open contact KM1 of the alternating current contactor KM is connected with the inductance coil L in parallel to form an isolation bypass.

2. The starting current suppressing device for a high-capacity series resonance voltage withstand apparatus according to claim 1, wherein: the alternating-current contactor KM switching-on coil is connected with an auxiliary contact KT1 of a time relay KT in series, and two ends A1 and C1 of a series circuit are connected into a circuit breaker (11) to output 380V.

3. The starting current suppressing device for a high-capacity series resonance voltage withstand apparatus according to claim 1, wherein: the closing coil of the time relay KT is connected with an auxiliary normally open contact QF2 of a circuit breaker (11) in series, and two ends L, N of a series circuit are connected into a power transformer 220V.