Design and evaluation of main terminal connectors for power modules in the service environment of high-speed EMUs
This paper aims to improve the service reliability of main terminal connectors for power modules in the service environ-ment of high-speed EMUs.To achieve this,the fatigue reliability of the solder layers in the main terminal structure of insulated-gate bipo-lar transistors(IGBTs)was studied through finite element analysis.Inaddition,the fatigue life of the solder layers was predicted by lever-aging different theories and the prediction results were verified by power cycle experiments.The study results show that the number of cycles decreases slightly with the increase in the void rate of the solder layers.Additionally,as the solder layer thickness increases,the number of cycles initially increases before subsequently decreasing.During the power cycle experiments,the degradation of the solder layers manifests as the coarsening of the grey phase containing Sn.The analysis obtained using the energy-based Darveaux model more closely aligns with the degradation process of the solder layers in the main terminal structure of IGBTs.Hence,the thickness of solder layers is identified as the primary influencing factor on the service life of the main terminal structure.
high-speed EMUinsulated-gate bipolar transistors(IGBT),solder layer fatiguereliabilityfinite element analysis