A comparative study of the gate driver circuits for series stacking of semiconductor switches

For the high voltage semiconductor switch based pulsed power application, series operation of semiconductor switches is generally required because of limitation of device ratings. However, there are many considerations to design gate driver circuit for stacking the IGBTs because of the complexity and difficulty of synchronization and protection. Gate driver circuit of series connected IGBTs usually requires high number of high voltage insulated gate power source and complex gate signal schemes depending on the total number of switches. Furthermore, since it is difficult to synchronize switching operations, complex protection circuit should be employed to protect semiconductors switches from arc or short circuit condition which is frequently generated during normal operation of pulsed power application. The purpose of this study is the introducing of the simple and reliable gate driver circuits for series connected semiconductor switches based on the expected problems and considerations. The advantages of each driver circuit are analyzed based on comparative study of proposed gate driver circuits with PSpice simulation. By combining driver circuit with 12 series connected IGBT stack for 10 kV pulsed modulator, the various kinds of testing were performed including normal operation and arc or short condition. The experimental results is confirmed that proposed gate driver circuit can be effectively used at semiconductor based pulsed power modulator.