Authors: Y. Tronel and W. Fichtner
Affilation: Swiss Federal Institute of Technology Zürich, Switzerland
Pages: 88 - 93
Keywords: IBGTs, damage, pure aluminium, finite element model
Insulated Gate Bipolar Transistors (IGBT's) are widely used in the automotive industry as high power current switches. They are currently being introduced into traction applications (locomotives, trams, metros, etc.) where high reliability is extremely important. Modern locomotives have a lifetime of about 30 years during which they should not fail. Due to the complexity of the modules as mechanical systems and as electric circuits, it is of prime importance to select and set up the most suitable models which allow to extract valuable data. Accordingly, this work describes the models and associated equations which appear to be necessary to carry out failure analysis. It includes a general stationary fully coupled electro-thermomechanical analysis which is actually part of the commercial release of the software SOLIDIS-ISE. More specific features tailored to IGBTs failure analysis are currently implemented. It comprises thermal transient effects and plasticity/damage based models for the stress analysis. Finally, a numerical example showing the damage distribution at a wire bond connection is presented.