Experimental investigation of the LLC-type parallel resonant converter

Based on the theoretical analysis of R. Liu et al. (see Proc. High Freq. Power Conv. Conf., p.486-96 (1989)), a complete set of design curves for the LLC-type parallel resonant converter is derived. Using these curves, a design procedure for the converter operating in the continuous conduction mode and with natural commutation is formulated. As an example, a 150 W, 150 kHz, multioutput LLC-type parallel resonant converter power supply was designed and tested. Various test waveforms for the output load variation from 10% load to full load and the input voltage variation from 90 VAC to 130 VAC line voltages are presented. The experimental results and the theoretical values are in good agreement.<
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