Abstract: Comparative study on the thermal simulation of heatsinks on electric vehicle with various configurations for Insulated-Gate Bipolar Transistor has been undertaken in this paper. For the purpose of validation of numerical module, a simulation was conducted in the first place for diamond pinfin heatsink. The reliability of the chosen fluid model, mesh density and material properties have been demonstrated through the close agreement between the numeral results and experimental data. With the verified model, a circular pinfin heatsink has been established to ensure the identical pressure drop with diamond one in order to identify the dimension of the circular pin. By introducing the power module with certain power loss, the thermal simulations on these two heatsinks have been carried out. Through the comparison of the numerical results, it has been shown that the junction temperatures of the power modules from circular configuration are about 1.5% higher than the ones from diamond one and the highest surface temperatures of the heatsinks are in good consistence. Nevertheless, these results comply with the product specifications.With the consideration of 27% weight loss compared to the diamond pinfin structure, circular pinfin configuration is assumed as a better choice for power module heatsink. In this study, the verified numerical model contributed to analyse the heat dissipation and temperature distribution of the power module and helped to select the optimum configuration of pinfin structure. Hence, the experiment cost and time for the product development can be substantially reduced.

Key words: Power module; Heatsink; Numerical simulation; Pinfin

摘要： 文章采用 Fluent 软件对用于绝缘栅双极型晶体管芯片的电动汽车不同构型散热器进行 流体热仿真对比分析。为了验证流体数值模型的可靠性，先对菱形 pinfin 散热器进行了仿真 分析，通过与试验数据的对比，表明了选择的流体模型、网格密度和材料参数的正确性。采 用已经验证过的数值模型，建立了圆柱 pinfin 散热器构型，同时保证其压力损失与菱形 pinfin 散热器一致以确定尺寸。通过添加功率模块的功率损失，对这两种构型散热器进行了热仿真 分析。通过对比可以发现，圆柱形 pinfin 散热器的功率模块结温会比菱形的高约 1.5%，散热 器的表面最高温度则基本保持一致，但均符合产品设计标准。考虑到圆柱形构型可以将 pinfin 结构减重 27%，其将是功率模块散热器的更佳选择。本研究通过验证的数值模型，快速分析 功率模块的散热与温度分布，选择更优的 pinfin 结构，减少了后期试验成本与产品开发时间。

关键词: 功率模块；散热器；数值仿真；Pinfin