Active Power Control Strategy with Load Impedance Estimation Method for IH Cooktop Considering Utilization of Double-bottom Pot

For conventional domestic induction cooktop using series resonant inverter, the reference power of system can be controlled by frequency variation. In this case, the controller only monitors the input power condition to satisfy target power level. However, when the double-bottom pot is located on a working coil, system can be damaged by large magnitude of output current under the same target input power since the equivalent impedance of load highly decreases compared to ferromagnetic pot. Therefore, in this digest, active power control strategy is established with mathematical analysis of load impedance without obtaining input power curve data. Through experimental results using 3.2 kW test bed, the validity of proposed method is evaluated.