A Review of the Series Resonant Converter Operating in the Capacitive Side of the Resonant Curve in Domestic Induction Heating Application

摘要

Induction heating (IH) technology is already well-known in domestic cooking mainly thanks to its superior energy efficiency. The series resonant converters are mostly used in high-end IH cooking appliances, with power ratings up to 3-4kW and driven with variable frequency power control in the inductive side of the resonant frequency curve. This operating range allows to take advantage of zero-voltage switching (ZVS) turn-on commutation and to work at switching frequencies high enough to avoid acoustic beatments between different hobs working at different frequencies within the same cooktop. Nowadays, the trend to increase operating frequencies to reduce coil size and cost, makes worth analyzing the operation in the capacitive side of the resonant curve, where, in contrary to the current inductive side control scheme, hard switching turn-on and zero-current switching (ZCS) turn-off occur. This paper discusses significant benefits of capacitive side control scheme by using the optimal IGBT and Diode better efficiency, lower EMI and higher reliability performances can be achieved.