Passive high-voltage direct-current circuit breaker and implementation method therefor

Abstract

A passive high-voltage direct-current circuit breaker and an implementation method therefor. The high-voltage direct-current circuit breaker is connected in a direct-current system in series, and comprises an energy absorption branch, a main branch and a current transfer branch which are connected in parallel, wherein the current transfer branch comprises first current transfer branches (T1, T2) and second current transfer branches(T3, T4); the energy absorption branch is composed of a nonlinear resistor (MOV); and the main branch comprises at least two groups of high-speed mechanical switches (K1, K2) and at least two groups of full controlled device modules which are connected in series. Since the circuit has a simple topology structure, is simple and convenient to control, and is flexible to apply, the energy required by injecting a current into a capacitor can be obtained from a system without configuring an auxiliary power source, thereby improving the reliability of an apparatus. The used power electronic devices are mainly half controlled thyristors, so that the series connection technology is mature, the capability for current segmentation is strong, the level of withstand voltage is high, the expansion capability is strong, and the costs of devices are low.

Description

technical field [0001] The invention relates to a DC circuit breaker, in particular to a passive high-voltage DC circuit breaker and its realization method. Background technique [0002] With the application of multi-terminal flexible DC and DC grid technology based on voltage source converter (VSC), fast DC circuit breakers have become one of the key equipment to ensure the stable, safe and reliable operation of the system. In the AC system, the AC current has two natural zero-crossing points in one cycle, and the AC circuit breaker uses the natural zero-crossing points of the current to cut off the current, while in the DC system, the DC current does not have a natural zero-crossing point, so the DC current The breaking of the current is much more difficult than the breaking of the alternating current. [0003] There are usually three ways to break the DC current. One is to add an auxiliary circuit on the basis of the conventional AC mechanical circuit breaker to superimp...

AI Technical Summary

Problems solved by technology

[0003] There are usually three ways to break the DC current. One is to add an auxiliary circuit on the basis of the conventional AC mechanical circuit breaker to superimpose the increased oscillation current on the DC current of the breaking arc gap, and use the current to break when the current crosses zero. The mechanical circuit breaker manufactured using this principle cannot meet the requirements of the multi-terminal flexible DC transmission system in terms of breaking time; one is to use high power to turn off power electronic devices and directly break the DC current, using this principle Although the manufactured solid-state circuit breaker can meet the requirements of the multi-terminal flexible DC system in terms of time, the loss is

Images