Analysis of the Algorithm for Changing the Output of Induction Heaters for Electric Vehicles

Abstract

In the battery heating of the electric vehicles(EVs), existing vehicle with internal combustion engines use the heat generated by the engine to heat the cooling water. However, EVs doesn’t have an engine, so additional system is needed to generate heat. Maxwell tools were used to conduct this study. Model induction heater in 2D and perform FEM analysis. Induction heaters generate heat by the AC current of the coil inducing eddy currents on the workpiece surface. A big feature of induction heaters is that they operate in the high frequency range, so heat is concentrated on the surface. We analyze this by using FEM and propose an output change design algorithm for various parameters. The characteristics of the induction heater operating in the high frequency range create a skin effect phenomenon in which eddy currents and magnetic fluxes are concentrated on the inner and outer workpiece surfaces. To take this into account, the FEM analysis tool was used to split the workpiece into units and to focus the mesh on the surface. In order to simulate the IGBT, the Maxwell-supplied devices set the external circuit and derive the output according to the duty ratio. In this paper, the magnetic flux density distribution for each output is derived. These results extend to the design of the output change. The key to this study is the effect of duty ratio on the output. Within the 50% limit, we consider the effects of the larger output and the smaller output as the duty ratio and the characteristics of the relationship between the duty ratio and output. In this paper, an algorithm for the relationship between duty ratio and output is presented. Induction heater having the advantages of weight reduction and fast heating rate can be utilized to maintain the proper temperature of the battery for the electric vehicle, it can be utilized for room heating.