Current Phase Analysis of the Induction Heating System with an Intermediate Coil

Induction cooker, have a huge market because of their high efficiency, short heating time, safety and other advantages. Among the operating characteristics of induction cooktops, heating uniformity is a property of great concern, and there have been several studies based on the effect of different coil structures on the heating uniformity of induction cooker, in which the heating coil is divided into 2–3 regions to improve the heating uniformity, but the effect of the phase of the current in the coil on the heating uniformity has not been paid attention to in these studies. For this reason, a mutual inductance-based impedance phase model is proposed in this paper. By analyzing the circuit model, the phase angle of the primary and secondary currents is deduced. On this basis, finite element simulation is carried out to analyze the induction heating uniformity of induction cookers with different phases, and the phase range with more uniform heating is obtained by comparison.