An IGBT Current Boosting Method by Using Ultrahigh Driving-Voltage in HVdc Circuit Breaker Applications

High-voltage direct current (HVdc) circuit breakers based on power electronic technology usually require a large number of insulated-gate bipolar transistors (IGBTs) to achieve large-capacity breaking. The insufficient current capacity is an important reason for the excessive cost of dc circuit breakers. However, the single switching condition in the circuit breaker makes it possible for IGBTs to control the current of several times rated value in a short time. This article proposed an effective current boosting method for IGBT. By applying an unconventionally ultrahigh driving-voltage (UDV) to the gate of devices, the instantaneous current capability of IGBTs can be significantly improved. The possible failure modes and lifetime issues caused by UDV are also discussed in detail. Through comprehensive theoretical calculations and experimental analysis, a proper UDV selection principle for IGBTs in HVdc circuit breakers is proposed. The single device is verified to have the ability to control 31.2 kA current in milliseconds by using UDV. This conclusion can greatly increase the allowable working area of IGBTs, thereby significantly reducing the cost of HVdc circuit breakers.