Short-circuit fault current-limiting transformer

Abstract

The invention relates to the technical field of circuit fault current limiting, and specifically relates to a short-circuit fault current-limiting transformer. The current-limiting transformer comprises a transformer and short-circuit protection circuits. The secondary coil of the transformer is composed of three identical secondary coils. A low-voltage tap is led out from each of the three secondary coils. One short-circuit protection circuit is connected between each low-voltage tap and the high-voltage end of the corresponding coil. Each short-circuit protection circuit is a current limiting loop in which one low-voltage tap is sequentially connected in series with an auxiliary reactor, a short-circuit protection switch and a capacitor and then connected with the high-voltage end of the corresponding secondary coil, wherein the capacitor is connected in parallel with a power supply switch, and the common joint of the power supply switch and the short-circuit protection switch is connected to a power supply circuit. At the moment when a line fails, a large impedance is added between the power supply and the fault point, and thus, the fault current is limited.

Description

technical field [0001] The invention relates to the technical field of circuit fault current limiting, in particular to a short circuit fault current limiting transformer. Background technique [0002] With the vigorous development of all walks of life in society, the demand for electricity as an energy source has become more prominent, and the capacity of the power grid has expanded rapidly. At the same time, the level of short-circuit current in the power system has also reached a severe level. Safety issues and economic issues force people to do a lot of research and implement some measures passively and actively, and therefore fault current limiting technology has appeared, especially in the past ten years, short-circuit fault current limiting technology has developed rapidly, such as superconducting fault current limiter , power electronic fault current limiter, permanent magnet fault current limiter, etc. are all hot topics of current research, and there are many branc...

AI Technical Summary

Problems solved by technology

[0004] The invention provides a short-circuit fault current-limiting transformer, which solves the problem of poor short-circuit resistance of the transformer

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