| With the development of power electronics, the fast semiconductor switching devices can increase the dynamic response speed, and it produces the large electromagnetic interference (EMI). The EMI not only influences the load's usual work and cuts the load's work life, but also hurts inverter itself. The research in this thesis is mainly about electromagnetic interference (EMI) in inverter. Based on the platform of the finite element analysis software ANSYS, this paper researches the methods of building the finite element three-dimensional solid model in voltage source inverter firstly, which is used of analysis EMI phenomenon of the voltage source. According to the structure characteristics of ordinary circuit elements such as inductor, capacitor, resistance, diode, MOSFET and so on, the models of these elements were built by means of combing the layer and segment, and some theoretic analysis were implemented to demonstrate the correctness of these models. Based on these element models, the inverter space model was built and some quantitative electromagnetic analysis was made .The analysis results prove the rationality and validity of the model. Secondly, as for the far field characteristic of inverter, this paper discusses the characteristic of main radiant point in inverter circuit systematically and focuses analysis on the common mode EMI of heat-sink and differential mode EMI of high frequency current ring. Then EMI of common mode current produced by heat-sink and differential mode current produced by high frequency current ring was analyzed. The radiation effect of heat-sink and high frequency current ring was discussed on different geometry shape, size, assemble way and so on. At last, this model was validated by the way of experiment. Thanks to the literature report of the inverter electromagnetic radiation problem in the magnetic distribution angel of quantitative analysis is rare, above research works have academic and applied worthiness.
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