Research on characteristics of 6-inch IGCT with 15kA turn-off capability in DC circuit breaker

Abstract

The development of DC power grids requires DC circuit breaker(DCCB) to have higher breaking capacity. As a key component of DCCB, the withstand voltage and breaking capacity of power electronic devices affect the structure and cost of DCCB. Therefore, it is necessary to upgrade power electronic devices to improve the breaking capability of DCCB and reduce costs. Integrated gate commutated thyristor (IGCT) has great advantages in the application of DCCB due to its inherent high inrush current capacity and low on-state loss. This article introduces a novel IGCT used in DCCB. It is based on the existing 6-inch 4.5kV GCT chip and shell structure. After designing a new gate unit and optimizing the turn-off circuit, it effectively improves the turn-off capability of the device. In the DC circuit breaker application topology, the device has a turn-off capability of 15kA at 2400V. This new device is expected to further increase the breaking capability of DCCB in the future.