Fault Current Bypass-Based DC SSCB Using TIM-Pack Switch

This letter proposes a new bypass-based solid-state circuit breaker (SSCB) using a thyristor–insulated-gate bipolar transistor (IGBT)–metal oxide varistor (MOV) switch, named TIM-Pack, for dc applications. The presented SSCB features three key advantages. First, the stored inductive energy of dc systems is prevented from flowing through faulty sections, and the reaction speed is within microseconds, which enhances safety. Second, MOVs are disconnected from the power line during the off state, which improves reliability. Third, the proposed topology takes full use of the benefits of high-power rating thyristors in a TIM-pack. To validate the proposed SSCB, experiments on a 600-V/145-A scale-down prototype are conducted. Results show that the fault current reduces to zero in 6 μs, and the peak voltage on the main and auxiliary thyristors reaches 826 and 600 V, respectively, whereas the overshoot voltage on the main and auxiliary IGBTs reaches 185 and 245 V, respectively.