T13.8 - An All-Metal-Compatible Induction Cooking System with Double-D Coils

Induction cooking is gaining increasing traction as an energy efficient cooking technology as it directly heats the cooking vessel by inducing currents in it. Other advantages include precise control over the temperature and speed of cooking. Due to the high electrical conductivity and lack of magnetic properties, metals such as aluminum are not usually compatible with most commercially available induction cooktops. This work proposes an-metal compatible induction cooktop which utilizes an input tap changing impedance matching transformer connected to the output of a variable frequency full bridge converter. The transformer tap is set depending on the type of cookware. Further, the proposed induction cooking system employs double-D coils which make the magnetic field distribution more uniform over the surface of the cooktop, thus enabling more uniform heating of cookware of different sizes. Simulation and experimental results on cooktop performance with both circular and double-D-coils are presented.