A modular bi-directional hybrid circuit breaker for medium and high voltage DC networks

The development of dc transmission and distribution technologies are gaining traction. With renewable energy being fed to the grid constantly increasing, there is growing interest in development of dc grids. A major hindrance for their development is attributed to the lack of protection during short-circuit fault. Hybrid circuit breakers, a combination of mechanical and semi-conductor devices are understood to be the most effective method to protect dc grids against such faults. Several of such hybrid breakers are published and patented but still a practical high voltage dc breaker has not been developed. In this paper a novel modular hybrid circuit breaker is presented. This paper tries to address limitations present in existing breakers and a scalable model which can be used for both medium and high voltage dc networks is proposed.