Selection Procedure of Resonant Tank Parameters for an SiC MOSFET based DC/DC Series Resonant Converter

A systematic approach to select the resonant tank parameters for a DC/DC Series Resonant Converter (SRC) is proposed in this paper. The drawbacks of using sinusoidal approximation model, while selecting those parameters, are also discussed in this paper. Quality factor of the system is derived from an equivalent circuit to get an insight about the harmonics present in the tank current, for a different combination of L and C values. The presence of harmonic components in tank current deteriorates the performance of SRC by increasing conduction and switching losses. A detailed investigation is carried out in this paper to find the factors, responsible for the harmonics in the tank current, through theoretical analysis and simulation studies. Besides, voltage drop across the series capacitor plays a critical role in this selection process, which is also included in this paper. A laboratory prototype of 2kW, 45kHz SiC MOSFET based SRC is built to verify and validate the proposed method.