A micro-loss combined mechanical DC circuit breaker with reclosing function

Abstract

The invention relates to a micro-loss combined mechanical DC circuit breaker with a reclosing function. The micro-loss combined mechanical DC circuit breaker comprises n terminals, n through-current branches, and one current-commuting branch, wherein n through-current branches are connected with one current-commuting branch in parallel, each through-current branch is divided into an upper bridge arm and a lower bridge arm by taking a connecting point as the boundary; each terminal is electrically connected with the connecting point of one through-current branch; the upper bridge arm of each through-current branch comprises one auxiliary mechanical switch, and the lower bridge arm comprises an isolation switch and a semiconductor switch component in serial connection; the current-commutingbranch comprises a main mechanical switch, a high-voltage arm capacitor and a low-voltage arm capacitor in serial connection; the high-voltage arm capacitor is connected with a high-voltage resistor and an arrester in parallel, and the high-voltage arm capacitor is unnecessary to be pre-charged; the low-voltage arm capacitor is pre-charged with a certain voltage, and the low-voltage end of the low-voltage capacitor is electrically connected with the high-voltage arm capacitor directly.

Description

technical field [0001] The invention relates to the technical field of power equipment, in particular to a micro-loss combined mechanical DC circuit breaker with a reclosing function. Background technique [0002] In the DC power grid, DC circuit breakers are urgently needed to quickly isolate DC side faults, so as to ensure the reliable operation of normal converter stations and lines. [0003] At present, the mainstream technical routes of DC circuit breakers are divided into hybrid DC circuit breakers and mechanical DC circuit breakers. Among them, mechanical DC circuit breakers have the advantages of low cost and low operating loss, but they have the disadvantage of being unable to achieve fast reclosing. A typical mechanical DC circuit breaker topology is as figure 1 and figure 2 As shown, the mechanical DC circuit breaker includes a flow branch, a commutation branch and an energy absorption branch. The normal load current is conducted by the flow branch, and the ci...

AI Technical Summary

Problems solved by technology

In other words, the number of DC circuit breakers that need to be configured in the DC power grid is huge, and the cost of DC circuit breakers is expensive, which in turn causes a substantial increase in the construction cost of the DC power grid

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