Direct-current circuit breaker for low-voltage direct current

Abstract

The invention relates to a direct-current circuit breaker for a low-voltage direct current. The direct-current circuit breaker comprises a through current branch and a conversion current branch whichare connected in parallel; and a circuit breaker contact is arranged in the through current branch in series, a conversion current control switch and a capacitor are arranged in the conversion currentbranch in series, a dissipation branch is connected to the two ends of the capacitor in parallel, and a lightning arrester is arranged in the dissipation branch in series. According to the direct-current circuit breaker, by improving the arc extinguishing mode of the low-voltage direct-current circuit breaker and arranging the circuit breaker contact with the low voltage level in the through current branch in series, the low voltage with the high level can be cut off, the advantages that the size of an arc extinguishing chamber is small, and the life of the contact is long are achieved, and the requirements on current breaking of the low-voltage direct current in different working environments can be met.

Description

technical field [0001] The invention relates to a circuit breaker, in particular to a DC circuit breaker for low-voltage direct current. Background technique [0002] The power supply system of rail transit includes high, medium and low voltage AC power supply system, DC power supply system and centralized power monitoring system (SCADA). The electrical equipment in the DC power supply system includes rectifiers, DC fast circuit breakers, DC switchgear, etc. Among them, the DC switchgear is one of the core equipment of the rail transit power supply system, and the DC circuit breaker in the DC switchgear plays a role in the DC switchgear. to a vital role. [0003] At present, there are three main types of technical solutions for DC circuit breakers, namely traditional mechanical DC circuit breakers based on conventional switches, solid-state DC circuit breakers based on pure power electronic devices, and hybrid DC circuit breakers based on the combination of the two. Among ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a DC circuit breaker for low-voltage DC, which is used to solve the problem that the DC circuit breaker in the rail transit system requires a large volume of arc extinguishing chamber and severe contact ablation, which cannot meet the low-voltage DC current breaking requirements. demand problem

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