Electrothermal analysis of temperature-limited loads for domestic induction heating applications

One of the most important factors in the development of a home appliance is the safety of the users. For this reason, the temperature control and the protection against human errors, such as the abandonment of the cookware while cooking, are always of interest in induction heating applications. This paper presents a solution for self-limiting the temperature in cooking vessels that prevents its overheating, protecting the system and preventing food from burning. It is proposed the manufacture of cookware with materials whose electromagnetic properties change at a preset temperature within the range of interest in cooking, these changes cause the power transmitted to the load to drop considerably providing self-protection capabilities against overheating. This solution does not require additional sensors or communication with the induction cooktop, making it a simple and economical option. The performance of the proposed solution has been analyzed using a multiphysics tool, which includes electromagnetic and thermal submodels, and allows to obtain the temperature distribution and the changes in the system as the vessel heats up. Finally, an experimental verification of the model and the solution has also been presented.