Mission-Profile-Based Reliability Evaluation of IGBT Modules for Wide-Speed Range Electric Vehicle Drive Using Fast Multistep Mapping Simulation Strategy

Abstract

Reliability-oriented evaluation of power module has emerged as a pivotal aspect in addressing the demands of high-reliability design and cost-effective maintenance for electric vehicle (EV) converter. In this article, a fast simulation strategy based on mission profile (MP) is proposed for a 750-V/820-A insulated gate bipolar transistor (IGBT) module used in an EV converter. This strategy depends on a multistep mapping structure, including the MP, load condition, and junction temperature with detailed electrothermal modeling. A numerical mapping process enables decomposing the MPs to the load conditions. The natural decoupled first-order thermal model improves the efficiency of the thermal stress mapping process greatly, and the error between the mapping results and other strategies, e.g., finite-element method (FEM) and circuit simulation, is less than 3%. Using the strategy allows the creation of lookup tables (LUTs) covering all load conditions in a wide-speed range, which is capable of simulating very long MP in minutes while retaining circuit-based simulation accuracy. Furthermore, both the fundamental- and low-frequency damages are considered in the reliability evaluation. The proposed strategy can be extended to consider additional failure mechanisms, which helps to further optimize their reliability and cost effectiveness.