Abstract:

With the continuous advancement of photovoltaic and energy storage system technology, the voltage has been raised to the mainstream of 1 500 V, and the multi pole series connection is usually used to meet the demand for continuous voltage increase, resulting high cost, large volume, and certain limitations in the use category of existing DC isolation switch products. Therefore, a discussion is conducted on the operating conditions of DC isolation switch products, analyzing the differences in expected current waveforms under different time constants, proposing an improved arc extinguishing chamber structure, and analyzing the experimental results caused by the differences in arc extinguishing capacity of isolation switch products under different usage categories, providing new insights for enhancing the applicability of switch products in voltage systems that are continuously being upgraded.

Key words: direct current system, isolation switch, arc extinguishing capacity, time constant