A new resonant soft switching topology for direct AC-AC converters

This paper shows that the most significant percentage of switching losses in a matrix converter is incurred while switching high voltage and current. A soft switching auxiliary circuit is proposed which has the ability to achieve ZCS under a wide range of operating conditions. Using the proposed topology it is possible to disable the auxiliary switch when the current and/or voltage is low. This simplifies the design of the auxiliary circuit as the range of operating conditions is reduced, allowing better optimisation in terms of switching loss and commutation speed. The authors present results from a laboratory prototype and Saber simulations to verify the feasibility of the proposed topology.