A power electronic transformer based on indirect matrix converter for PWM AC drive with lossless commutation of leakage energy

High frequency ac link three phase ac to three phase adjustable speed and magnitude PWM ac converters with single stage power conversion and bidirectional power flow are important in the generation of power from renewable energy sources or where isolation is necessary. Due to the use of high frequency these type of converters achieve high power density. Open loop power factor correction, higher efficiency and reliability are important features of these type of converters. One major problem in this type of converter is the commutation of leakage energy which results in power loss, reduction in switching frequency, distortion and loss of output voltage. The topology based on the indirect modulation of matrix converters uses minimum amount of copper and has relatively less number of semiconductor switches. This paper presents a lossless source based commutation strategy along with a modulation technique that minimizes the frequency of leakage inductance commutation. It also results in the soft switching of the output converter (Zero current switching : ZCS). The topology along with the proposed control has been analysed and simulated. Simulation results confirm the operation.