The Analysis Of Multi-physics Fields Coupling On Induction Heating System

Induction heating(IH)technology directly generates heating on the induction target,and thus it is safe,clean,quickly heating and highly efficient compared with the traditional contact-heating methods,and has attracted increasingly attention in recent decades.The IH process is a complicated nonlinear multiphysics coupling process affected by the manufacturing process.At present,there is no precise mathematical model to describe the process.Moreover,there are some electromagnetic compatibility issues caused by the radiated electric field under working condition of domestic IH system.All these problems are difficult for IH system design.This thesis combines electromagnetic field theory and finite element simulation technology to study electromagnetic parameters of the domestic IH systems,multiphysics coupling in the domestic IH systems,and electromagnetic compatibility issues in the domestic IH systems to provide theoretical basis and simulation methods for the design of domestic IH systems.The main work and research results of this thesis are as follows:1.With full investigation and study of research emphases and research methods for the domestic IH technology,an equivalent circuit model of a domestic IH system is established according to electromagnetic field theory.The equivalent electrical parameters of the domestic IH system under small-signal excitation can be quantitatively obtained by calculating the equivalent circuit model,and it can also qualitatively analyze the heating efficiency of the domestic IH system influenced by some factors.2.The 3D finite element model of the domestic IH system is developed by ANSYS finite element simulation software,and coupling between the electromagnetic field and the temperature field in IH process is reproduced through the simulation.3.The time domain simulation model and radiation field simulation model of the domestic IH cooker are established by analyzing the circuit of the domestic IH system.The power distribution of the domestic IH cooker under working condition is analyzed by simulation of the time domain behavior of the domestic IH cooker.The coupling effect between the PCB and IH systems affects distribution of the radiation field comparing distribution of the radiation field radiated by either the sole PCB or the sole IH system.4.Based on the 10-meter EMI simulation results of the domestic IH cooker,this thesis proposes two methods that can effectively reduce the radiated EMI by adding the snubber circuit and reducing the ground loop.5.The experimental tests validated the proposed equivalent circuit model for the domestic IH cookers,the simulation methods for multiphysics coupling,and the time-domain behavior simulation model for the domestic IH cookers,which have an important role in the design of the domestic IH systems.