Complementary Commutation-Based Π-Type DC SSCB

This digest introduces a new dc solid-state circuit breaker (SSCB) using a complementary commutation technique. The proposed SSCB employs a capacitor-capacitor pair topology in a Π structure, called II-type SSCB. The capacitor-capacitor pair structure helps to achieve a reliable and fast re-closing and re-breaking process. The presented topology mostly benefits from its simplicity. It removes the voltage on passive components during the SSCB OFF-state, which enhances reliability. The II-type SSCB needs no charge/discharge circuits, and it solely depends on the dc system itself. In addition, the introduced SSCB facilities using high-power rating thyristors in the main and auxiliary branches, making it one of the best solutions for medium-voltage section. Two modified topologies are also presented to extend the applications of II-type SSCB in practice. To verify the effectiveness of the proposed topology, experiments of 500 V/50 A prototype are conducted. The results show the reaction time interval of 42 μs under load current interruption, where the peak voltage on the main and auxiliary thyristors reaches 581 V and 500 V, respectively.