Reliability design for passive power semiconductors in electrical machines

The automotive industry is currently experiencing an unprecedented amount of innovation and introducing new technologies in almost every field. Even with all of these exciting new developments, one of the most important points is to maintain or improve the reliability and lifetime of cars. In response to these demands, automotive manufacturers and suppliers have worked to strengthen their expertise in this area.This paper gives you useful hints and shows the general process for reliability design using the example of passive power semiconductors in alternators. Alternators are used in vehicles to transform mechanical energy into electrical energy. It doesn’t matter, if the mechanical energy comes from the combustion engine itself or from braking phases during driving, so called recuperation.Driven by the current demands of automotive technology, electrical drives will gain more and more importance and market share in the market. The general approach to develop electrical drives including electronics, is similar to how most mechanical parts are designed and developed. After fixing the requirements and topology, the electromagnetic layout is in the lead. This physical domain defines the main geometries of the machine and the currents as well as the voltage level. Having this information, you have to decide about the best technology and according topology for your mechanical, electromagnetic, circuitry and electronic components. Design for reliability (DfR) in reference to BERTSCHE [1] should be considered during the whole development process.