Multi-break hybrid direct current breaker

Abstract

The invention discloses a multi-break hybrid direct current breaker. The multi-break hybrid direct current breaker comprises a main switch circuit, an oscillating circuit and an energy absorption circuit, wherein the main switch circuit is composed of three quick switches and three voltage equalizing circuits connected with the quick switches in parallel, the oscillating circuit is composed of thyristor valves T1-T4, a transformer, a capacitor and an inductor, and the absorption circuit is composed of a ZnO arrester. The multi-break hybrid direct current breaker is capable of bidirectionally and quickly breaking short circuit current in a direct current system in a non-arcing mode; the multi-break hybrid direct current breaker is low in conduction loss, low in cost, long in service life, strong in breaking ability, short in breaking time and low in implementation difficulty and improves the voltage equalization between breaks of each breaker so as to avoid the inconsistent braking voltage of each breaker due to breaking time difference; the circuit is faster and easier to reach a zero crossing point by means of active current injection.

Description

technical field [0001] The invention relates to an ultra-high voltage and ultra-high voltage power transmission and distribution technology, in particular to an ultra-high voltage DC circuit breaker used in ultra-high voltage and ultra-high voltage power transmission and distribution. Background technique [0002] In recent years, my country's DC transmission system has made remarkable achievements. At present, although the DC transmission technology has developed relatively maturely, compared with the flexible and diverse connection methods of the AC transmission system, there are only a few DC transmission systems in the world. It is a multi-terminal connection mode, and the vast majority are still two-terminal systems. The main reason is that there is no practical ultra-high voltage DC circuit breaker. When the two-terminal system develops to a certain extent, the emergence of the multi-terminal system will be an inevitable trend. At the same time, the development of power...

AI Technical Summary

Problems solved by technology

In a high-voltage system, the on-state voltage drop generated by a large number of fully-controlled devices connected in series can generally reach nearly 100 volts, and it is difficult to achieve complete transfer of current by relying on arc voltage. increase, the action speed becomes slower, and the arc generated will cause corrosion of the fast switch contacts

Common ultra-high voltage DC circuit breakers have limited breaking capacity and are highly dependent on arc extinguishing media, resulting in greater damage to the contacts. Using a single contact to divide the voltage is relatively large, which can easily lead to arc reignition and contact welding

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