A Gate Driver Circuit for Series-Connected IGBTs Based on Quasi-Active Gate Control

Growth in high-voltage power-conversion applications in recent years shows the importance and requirement of high-voltage/high-power converters in power electronic applications. The major limitation in this industry is the maximum voltage blocking capability of semiconductor switches. To overcome this restriction, the power switches are connected in series to build a high-voltage compact switch. This paper proposes a modified circuit based on quasi-active gate control, which provides the capability of connecting a desired number of insulated gate bipolar transistors (IGBTs) in series. In addition, overcoming the limitation of balancing capacitors' sizing, alleviation of low-frequency oscillations, and better turn-OFF characteristics are some improvements obtained by the proposed circuit. Simulation results show an excellent voltage balancing between four and eight series-connected IGBTs. Also, experimental results are presented to verify the performance of the proposed circuit.