2008 Volume 34 Pages 103-110
In this paper, multi-resonant zero current soft switching (ZCS) -PWM single ended push pull (SEPP) high frequency inverter is newly demonstrated for consumer induction heating (IH) appliances. The proposed inverter circuit has a novel ZCS cell consisting of high side main switch with lossless inductor snubber and active edge-resonant commutation cell (AERCC). The AERCC consisting of auxiliary diode, auxiliary resonant capacitor, auxiliary resonant inductor and auxiliary switch in parallel with the high side main switch arm. In the newly proposed inverter, heating power of IH cooking heater is controlled continuously during all heating power range under a principle of ZCS. The operating principle and performance analysis of the newly proposed inverter with asymmetrical pulse width modulation (PWM) control scheme are described using equivalent circuits in switching mode. This high frequency inverter can regulate heating power continuously from 0.25kW to 2.74kW in experiment with asymmetrical PWM control scheme. Finally, compared with conventional ZVS-PWM-SEPP high frequency inverter with asymmetrical PWM scheme, its power conversion efficiency of is high enough even in at low power range. The feasible effectiveness and practicability of the high frequency inverter treated here are substantially proved on the basis of experimental results for consumer IH cooking heater.
