Utility AC Frequency AC Connected High Frequency AC Cycloinverter with Non DC Smoothing Electroytic Capacitor Filter Stage

In this paper, a novel topology of soft switching PWM high frequency AC power conversion conditioning and processing circuit without DC smoothing Capacitor filter link from the voltage grid of commercial utility frequency AC power supply source with 60Hz-100V or 60Hz-200V is proposed and introduced for next generation consumer induction heating (IH) boiler applications as a hot water producer, steamer and super heated steamer. The operating principle of commercial utility frequency AC (LFAC) to high frequency AC (HFAC) power frequency conversion soft switching circuit defined as high frequency soft switching cycloinverter is described, which can efficiently operate under a principle of zero voltage soft switching and regulate by means of positive and negative alternate asymmetrical PWM synchronized with the commercial utility frequency single phase AC voltage. The dual mode control scheme based on high frequency PWM and commercial frequency AC voltage PDM for high frequency cycloinverter are discussed in order to extend its soft switching commutation operating range in spite of power regulation ranging from low power to high power setting. This power frequency changer as high frequency cycloinverter is developed originally for the high frequency induction heating boiler in promising consumer and industrial fluid pipeline systems. It is verified on the basis of experiment and simulation results of the soft switching high frequency cycloinverter using IGBTs which is more suitable for the business-use IH boiler using new electromagnetic induction heating dual packs fluid heater. Finally, the power regulation characteristics in addition to utility AC side line current harmonic components and power factor characteristics and power conversion efficiency characteristics of this high frequency cycloinverter treated here are evaluated and discussed from an experimental point of view.