Resonant PWM inverter linked DC-DC convertor using parasitic impedances of high-voltage transformer and its applications to X-ray generator

A description is given of a resonant DC-DC converter that uses both the leakage inductances and stray winding capacitances of a high-voltage transformer as LC resonant components and the input capacitance of high-voltage cables as a smoothing DC capacitor. The converter incorporates a pulsewidth-modulated (PWM) control based on a high-frequency inverter at constant frequency to adjust output over a wide range of loads, Its application to an X-ray generator power supply system is reported. A computer-aided state-variable analysis of the circuit is presented. Experimental results using a prototype transformer are given, covering output voltage control characteristics, maximum output power, and converter output waveforms in the X-ray generator.<>