Abstract:

With the rapid progress of new energy technology,the system voltage is increasing,and the breaking performance of DC circuit breaker is more stringent.DC miniature circuit breaker plays an important role in DC systems,which provides overload,short circuit and other protection for DC loads.The key interruption challenges of DC miniature circuit breakers are focused on,and performance enhancement research is conducted.Using series double break point to increase contact distance,“V” type dislocated arc extinguishing chamber and high performance gas-generating material to optimize air flow channel and arc extinguishing system,combining with simulation to enhance the rapid arc transfer capability.The test results show that the critical load current,electrical life,short-circuit breaking capacity and other key indicators are qualified.The research can provide technical reference for the design and application of high-voltage DC miniature circuit breakers.

Key words: DC circuit breaker, DC 1 500 V, non-polarity, high breaking capacity, arc extinguishing chamber, gas-generating material, double break point