ABSTRACT
This chapter introduces the reader to the philosophy of using resonant power converters in high-power conversion systems and provides several examples for circuits. The major issue with pulse width modulations (PWM) control of resonant PWM three-phase converters consists in the minimum pulse-width required for allowing the resonant swing of either voltage or current waveforms. In the early 1990s, power converters with soft-switching operations were reported to save up to 10% of the switching loss. The advent of technology in the power semiconductor industry and the required complexity in the control circuit of resonant converters minimized the application of this technique within the large-scale production of power converters in the range of 10–100 kW. The major merit of this second direction in research and development efforts was to acknowledge the potential drawbacks of using resonant converters and to establish a proper comparison of losses at the system level rather than at the switch level.
