Latest Advances and Trends in High Voltage DC Circuit Breakers

High Voltage DC Circuit Breakers have seen rapid technology advances recently, in terms of improved performance and lowering costs. Multiple 500kV DC CB units have been installed in Zhangbei project and 3 different technologies have been tested at high voltage at an independent laboratory in Europe. There is significant ongoing research worldwide with some laboratory prototypes reporting very fast insertion of counter voltage, in the timeframe below 1ms. Other technologies, with proven track record of cost-effectiveness at medium DC voltage levels are now upscaled to High DC transmission voltages. The DC grid protection strategy is also evolving, in response to DC CB advances and operating experience. CIGRE is completing 2nd working group on DC CB topic, and as IEEE and IEC have begun work on DC CB standard development, it is important to facilitate two-way discussion between professional community and key experts from manufacturers and research centers.