3-phase 3-level single-stage ac-to-dc series resonant converter

This paper presents a new three-phase, 3-level, pulse width modulated (PWM), boost-integrated ac-to-dc series resonant converter (SRC) with high frequency transformer isolation. This converter uses a new gating scheme suitable for integrating a boost converter with a PWM 3-level dc-to-dc SRC converter with above resonance operation. Principle of operation of this converter along with its different operating modes is presented with analysis. Based on the analysis design example of a 1 kW, 48 V, 50 kHz ac-to-dc series resonant converter is presented to explain design procedure. PSPICE simulation results of the designed converter are presented for different loads. Results show soft-switching operation, low switch voltage and low total harmonic distortion of this converter for a reasonably wide range of loads.