Low-loss multi-terminal DC circuit breaker and its control method

Abstract

The invention belongs to the field of multi-terminal DC circuit breakers, specifically relates to a low-loss multi-terminal DC circuit breaker and a control method thereof, aiming to solve the problems of large loss and high cost of existing bridge-type multi-terminal DC circuit breakers. The invention includes: a main circuit breaker, a resonant circuit and a mechanical switch group. The positive terminal of the main circuit breaker is connected to the DC bus and the positive terminal of the mechanical switch group. The negative terminal of the main circuit breaker is connected to the positive terminal of the resonant circuit. The mechanical switch The negative terminal of the group is connected to the negative terminal of the resonant circuit, and the output terminal of the mechanical switch group serves as the output terminal of a low-loss multi-terminal DC circuit breaker for supplying the corresponding positive pole of the DC line. The mechanical switches of the invention back up each other, and use a multiplexable resonant circuit composed of resonant inductors, resonant capacitors, switches and diodes to generate high-frequency resonant current, guide the mechanical switch current to cross zero and extinguish arcs, with high breaking reliability and small size. Small, low loss and low cost.

Description

technical field [0001] The invention belongs to the field of multi-terminal DC circuit breakers, and specifically relates to a low-loss multi-terminal DC circuit breaker and a control method thereof. Background technique [0002] In some application scenarios, a DC bus in the DC grid has multiple DC lines. In order to selectively remove faulty lines, each DC line port needs to be equipped with a DC circuit breaker. However, the construction cost of this configuration is too high. Using a single multi-terminal DC circuit breaker to replace multiple DC circuit breakers allows multiple ports to share expensive breaking equipment, which can effectively reduce construction costs and improve line breaking efficiency. [0003] Bridge-type multi-terminal DC circuit breakers are characterized by the fact that the most costly main circuit breaker part is shared. It has strong economic application prospects in DC power grid. However, this bridge-type multi-terminal DC circuit breake...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the above-mentioned problems in the prior art, that is, the problems of large loss and high cost of the existing bridge-type multi-terminal DC circuit breaker, the present invention provides a low-loss multi-terminal DC circuit breaker, which includes a main circuit breaker, Resonant circuit and mechanical switch group;

Images