Thermal analysis and design of power electronic parts assembled by heat sink in flyback switching AC to DC converters with case enveloped

This paper presents the thermal analysis and design of power electronic parts assembled by heat sink in flyback switching AC to DC converters with case enveloped. Firstly, both the analytic method and the field-circuit indirect coupling model are applied to calculate the maximum power consumed by the power electronic parts and the power loss of the converter. Secondly, based on the case temperature calculated by using the traditional equivalent circuit, a systematic method is introduced for selecting heat sinks for the power dispersion in the power electronic parts. Finally, in order to obtain the thermal distribution in the heat sink, the method of finite element analysis (FEA) is used. The FEA model for the performance analysis of thermal field is realized in MATLAB/Simulink surrounding, and the method for deciding some key coefficients in the unified thermal model is presented. The results obtained by FEA are in good agreement with those by analytical analysis.