Study of magnetic nonlinearities in materials with low Curie temperature applied to domestic induction heating

The analysis of the magnetic properties of alloys with low Curie temperature used in domestic induction heating is presented. These alloys allow the development of cookware with additional benefits with respect to regular cookware oriented to improve temperature control and the user’s safety. Firstly, an experimental method to characterize the magnetic permeability with respect to the magnetic field strength and temperature in the material is presented. Secondly, a finite element simulation method is proposed which, considering the previous characterization, allows the calculation of the electrical equivalent of an inductor-load system as a function of temperature and magnetic field. This method makes possible the application of finite element simulation in the frequency domain with nonlinear materials, which is of interest for the design of electronics associated with domestic applications of induction heating. Simulation results are experimentally verified with various ferromagnetic alloys with low Curie temperature at different power, temperature, and operating frequency ranges.