三相电压源逆变器内部IGBT模块温度的求解及评估

三相电压源逆变器的工作性能、使用寿命等方面均与其内部绝缘栅双极晶体管(IGBT)模块温度直接相关,故求解及评估该逆变器中IGBT模块的温度对于确保逆变器系统的安全可靠运行具有重要意义。针对现有模型及方法难以求解IGBT模块温度的问题,本文借鉴直接法的思想,提出了一种新的简单实用的IGBT模块温度求解算法。基于拟合及插值算法,推导并建立了IGBT模块功率损耗模型;基于电热比拟理论,探讨并建立了集中参数的IGBT模块等效Cauer传热网络模型,并将传热微分方程差分化;最终,在同一电路仿真器中构建出IGBT模块温度的求解算法。在三相电压源逆变器的算例中,通过与英飞凌IPOSIM的温度计算结果对比,表明本文算法最大误差为3.01%,且温度变化趋势与IPOSIM基本一致,最后利用该算法评估了逆变器在不同负载工况下的IGBT模块温度,所得结果可为合理地进行三相电压源逆变器的散热设计、长期可靠性评估等服务。

Temperature solution and evaluation of IGBT module in three-phase voltage source inverter

Aspects such as the working performance and service life of the three-phase voltage source inverter are directly related to its internal IGBT module temperature,therefore the evaluation of the temperature of IGBT module in this inverter is of great significance to ensure the safe and reliable operation of the inverter system.In view of that the existing models and methods are difficult to solve the temperature of the IGBT module,this paper presents a new,simple and practical algorithm for solving the temperature of IGBT module based on the idea of direct method.The power loss model of IGBT module is buih with the fitting and interpolation algorithm,the equivalent lumped parameters Cauer thermal network of IGBT module is studied and established based on the electric heating analogy theory,and the thermal differential equation is differentiated.Finally,a fast algorithm for solving the temperature of IGBT module is constructed in the same circuit simulator.In the three-phase inverter example,comparing to the IPOSIM simulation results,the maximum error of the proposed algorithm is 3.01％,and the trend of temperature change is basically consistent with that of IPOSIM simulation.Finally,the IGBT module temperature of the inverter under different load conditions is evaluated by using this algorithm,and the results can be used for the design of heat sink design,long-term reliability evaluation,et al.of three-phase voltage source inverter.