Zero-voltage switching in a constant frequency digitally controller resonant DC-DC power converter

A series-resonant DC-DC converter operating at a constant frequency above its resonant frequency is analyzed and experimentally tested. Using a state-plane analysis, the range of load for a given set of circuit parameters over which zero-voltage zero-current turn-on and zero-voltage turn-off (using lossless capacitive snubbers) are calculated and verified on a test circuit. A digital controller, designed previously for a quantized duty-ratio control in PWM DC-DC converters and now available in a gate array, is used to implement the constant-frequency control of the output voltage.<
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