A switch module stacked by a 4 × 3 IGBT array with balanced voltage sharing for PEF applications

A 4 × 3 IGBT (insulated-gate bipolar transistor) array designed for a high-power switch module implemented with balanced voltage/current sharing is proposed for generating pulsed electric fields (PEF) for many industrial applications. The PEF is known as a promising non-thermal pasteurization method that can be utilized to inactivate micro-organisms in liquid food with high-voltage pulsed power generated. The IGBT array and associated gate driver proposed herein offers an alternative than conventional large-sized power switches like thyristors and GTO (gate turn-off thyristor) etc., in a much smaller size and lower price. The design and implementation of such IGBT array are presented, along with the design and employment of balanced voltage sharing by snubbers to implement real-time fast voltage/current sharing to protect IGBT devices in the array from damages due to unexpected voltage/current surges. On the other hand, a novel gate driver is designed to drive multiple IGBT devices simultaneously by differential gate drivers biased at pre-determined voltage levels. Experiments are conducted to verify expected performance by the 3 × 4 IGBT array and their novel gate driver. It is validated that maximum voltage and current of 1.8 kV and 60A can be achieved with safe operation.