PDM and PWM hybrid power control of a voltage-source type high-frequency inverter for ozonizer applications

This paper presents a high-frequency voltage source-fed load-resonant IGBT inverter with a series-compensated resonant inductor and a high-voltage transformer for ozone generating tube drive, which operates under a principle of the PDM (pulse density modulation) and PWM based power control strategy. The high-frequency inverter is composed of a high-voltage transformer series compensated inductor and ozone generating tube which is based on the silent principle. The state-of-the art efficiency incorporating a voltage-fed type high-frequency load resonant inverter with PDM and PWM control scheme is demonstrated, and its operating principle is described for ozone generating tube driving. It is noted that the pulse density modulated series resonant high-frequency inverter using IGBTs makes an ozone generating system simple, thus leading to improve the ozone generation efficiency. Finally, it is proved in feasible experiment and simulation that the series load-resonant inverter type ozonizer developed in this paper provides stable silent discharge characteristics over a wide output power range from 10% to 100%.