A new delay time compensation principle for parallel connected IGBTs

The parallel connection of IGBTs is being applied in various low and medium voltage converters. The selection of the devices, the manual parameterization of gate units and the substantial device de-rating are substantial disadvantages of state of the art converters with parallel connected IGBTs. This paper introduces a new, low expensive and automated delay time compensation method without additional current measurements. The structure and function of the new scheme are described in detail. Finally, the performance of the new delay time compensation principle is verified by experimental investigations of two parallel connected (1700V, 450 A) IGBT modules.