Evaluation of IGBT Module Remaining Lifetime in Wind Power Converters Considering Impacts of Failure Location

Operational and health management for the reliability of power electronic converters requires sensitive condition monitoring and accurate estimation of the remaining lifetime. This study adds to the second aspect by examining the effects of failure locations on junction temperature profiles under different conditions. It is found that die-attach solder fatigue and direct bonding copper (DBC) solder fatigue, which occur frequently during the serving time, have different effects on thermal loads. This article investigates the dependence of thermal stress effects on failure locations and output electrical frequencies using finite-element models and proposes an updated strategy for the Cauer-type thermal model according to the failure location. Experimental results validate the proposed model. The remaining lifetime of the doubly fed induction generator converter is calculated under different health conditions and failure locations using a modified lifetime model. This article is intended for the health management of converter systems and is supposed to be in service reliably.