Latest practical developments of triplex series load resonant frequency-operated high frequency inverter for induction-heated low resistivity metallic appliances in consumer built-in cooktops

This paper deals with the new generation prototype of one-stage boost-half bridge (B-HB) series load resonant soft-switching high-frequency inverter with a lossless snubbing edge resonant capacitor and two selective resonant capacitors in series with inductive load for consumer induction heating (IH) appliances. The B-HB high frequency inverter treated here is based upon a dual series load resonant frequency selection strategy, changed automatically in accordance with resistivity of metallic materials as IH loads. In the first place, the triplex series load resonant high frequency (three times of switching frequency) operated B-HB inverter is demonstrated for IH non-magnetic low resistivity metallic pans/utensils fabricated by aluminum, copper and multi-layer of aluminum and stainless steel. In the second place, the fundamental series load resonant frequency (switching frequency) operated B-HB high frequency inverter is also described for IH magnetic high resistivity metallic pans/utensils fabricated by iron, iron cast and stainless steel. Finally, the principle of operation and inherent unique features of the B-HB high frequency inverter employing dual series load resonant frequency selection scheme in accordance with either low resistivity or high resistivity IH loads is presented from an experimental point of view, along with its operating steady state performance. This new generation B-HB frequency inverter type built-in IH cooktop with two/three ranges is put into practice for home energy utilizations in all electricity residential systems.