Short-Circuit Robustness Assessment in Power Electronic Modules for Megawatt Applications

In this paper, threats and opportunities in testing of megawatt power electronic modules under short circuit are presented and discussed, together with the introduction of some basic principles of non-destructive testing, a key technique to allow post-failure analysis. The non-destructive testing equipment at CORPE, center of reliable power electronics, Aalborg University, Denmark, is presented and its features are discussed in detail, together with some relevant results. Limitations of experimental analysis have also been addressed, together with the introduction of a mixed thermal-electrical simulation tool originally developed to study abnormal conditions and helping to predict very fast and dangerous thermal transient especially in case of worn out devices. The paper is concluded with an overview on present challenges in next-generation semiconductors for such high power ranges – basically silicon carbide – and new concepts for nondestructive testing of ultrafast power modules adopting such a technology