Voltage Sharing Control With Gate Resistance Modulation for Series IGBTs During Turn-on and Turn-off

A gate resistance control (GRC) for voltage sharing of series-connected insulated gate bipolar transistors (IGBTs) is proposed in this article. The gate resistance control method is one of the IGBT series voltage sharing methods. The gate resistance modulation is realized by switching on and off the branch circuit resistors connected in parallel with the gate resistor, which is based on the principle of adjusting the size of the gate resistance of the IGBTs to achieve the variation of the transient voltage of the IGBTs. As a result, the GRC is suitable for digitally controlled system. The application of GRC enhances the performance of series-connected IGBTs and bolsters system stability. In this paper, the operating principle of GRC, the circuit topology of two series-connected IGBTs, and the control strategy are carried out in detail.