PRACTICAL APPLICATION OF THE PHYSICS-OF-FAILURE APPROACH: SOFTWARE AND NEW RESOURCES FOR RELIABILITY PREDICTION OF POWER ELECTRONICS SYSTEMS

The motivation for this paper is the need for a new reliability analysis of a motor drive system placed in a harsh environment. The previous study was disregarded because it had been made using the reliability traditional approach, based on handbook constant failure rate models. Since this method is no longer recommended, the approach based on the physics of-failure (PoF) has been deeply reviewed by the authors to be applied in the aforementioned system. However, several difficulties were experienced when using this methodology for the reliability assessment of systems in operation. Discussions reported in the literature confirm that others face similar difficulties. As a consequence, new researches were released in the end of 2016, where a new approach could be identified. It is physics-based; however, it considers more realistic scenarios, since it is concerned about the devices mission profiles and the simpler empirical lifetime models. In this context, this paper debates this new reliability methodology and the process needed to investigate a motor drive system under this point of view. Besides, it raises a discussion about the challenges that the authors (and others) may experience to evaluate the reliability of motor drive systems subjected to environmental stress factors, such as those present in mining facilities. Finally, reliability software currently available are analyzed.