Low-Cost HVdc Circuit Breaker With High Current Breaking Capability Based on IGCTs

DC circuit breaker plays an important role in the reliability of HVdc system, but the large number of expensive press-pack insulated-gate bipolar transistors (IGBTs) is used at present, which is a serious impediment to HVdc development. Thus, the low-price integrated gate commutated thyristor (IGCT) becomes a promising alternative device. This letter presents a low-cost HVdc circuit breaker with high current breaking capability based on IGCTs. The topology and principle of the proposed HVdc circuit breaker are introduced at first. Then, the parameter design is analyzed. A scaled-down test successfully demonstrates the high current breaking capability of 15 kA. In the end, the cost comparison shows that this scheme can achieve 61.8% cost reduction of the commutation branch.