Control Strategies for Parallel Connected IGBT Modules

High current insulated gate bipolar transistors (IGBTs) are widely used. The main problems with high current IGBT modules are that they are expensive to manufacture and their switching frequency is typically lower as their switching loss is higher. In this paper, three IGBTs in parallel are employed in a half-bridge topology rated for 900Amps giving a total lower build cost and fast switching speed. Tests in a full bridge with a recirculating current are set up to thoroughly examine the performance. To ensure the current sharing is balanced among the three IGBT modules, the current of each IGBT will be measured by Rogowski coil and LEM and the temperature of each module will be measured.