Operating characteristics of MCTs in resonant DC link inverters

Improved performance of inverters may be obtained by increasing the switching frequency of the power semiconductor devices. Switching frequencies greater than the hard-switched limits may be obtained by using soft-switching techniques, The MOS-controlled thyristor (MCT) is a relatively new device showing a great potential in soft-switching applications involving high-power densities. Hence, the main objective of this paper is to extend the research work done on both soft-switched (resonant) inverters and MCTs by evaluating the operating characteristics of MCTs for switching frequencies up to approximately 75 kHz under a zero-voltage switching condition. A PCB is developed to subject the MCTs and passive components to stresses similar to those actually occurring in the resonant and actively-clamped resonant DC link inverter topologies. In addition, operation results of the operation of the MCT-based active clamp in the actively-clamp resonant DC link inverter and some practical implementation considerations are included