Final Activity Report Summary - PORTES (Power reliability for traction electronics) The main objective of PORTES program was the study of reliability of power electronics used in traction. This reliability is key to ensure a good operability of train, to minimise energy consumption and to extend the use of electric traction in others domains like electric cars. The approach followed in this program was to find the main failures in power converters and to understand the failure mechanisms. The corrective actions were then to act on the main activating parameters and conditions.The studies were focused on semiconductor chips (insulated gate bipolar transistors and diodes) and their packaging. The main reason is that semiconductor often is the weak link in the electrical energy transfer: - In order to understand the main failures and the field return, a statistical analysis with collected data from the field has been made.- Extensive works on temperature distribution inside IGBT packs have been carried out- Electrical robustness tests have been defined and carried out. The result is that the main failure mechanism put in evidence is dynamic avalanche due to over temperature.These above results leads to the definition of a new endurance power cycling test complementing the standard power cycling test widely used by power semiconductor manufacturer.
