Ageing study in aircraft electromechanical chain: systems modeling for property evolution monitoring

The evolution toward more electric aircraft and hybrid propulsion aircraft imply increasing power on board, hence more severe constraints on the elements of aircraft electromechanical chain. High voltages associated with low pressure environment at high altitude, increase the risk of partial discharge occurrence. This risk becomes even higher when operating temperature and thermal variations can have an impact on the insulating properties of materials over time. To avoid premature failure, ageing mechanisms are currently under characterization in the framework of the HighVolt project at IRT Saint Exupery. A large ageing campaign has started on different representative specimens of several sub-systems of an aircraft electromechanical chain. More particularly a stator-like test vehicle called motorette has been improved and placed under isothermal ageing for lifetime characterization. This paper presents the work achieved to get a highly repetitive winded test vehicles and its digital model twin in COMSOL to enhance failure mechanisms comprehension by correlating a set of monitored parameter. Capacitance and Partial Discharge Inception Voltage are first measured experimentally and then computed numerically to be compared. As a further work, the parameters drift will be studied by modifying the models according to the supposed ageing mechanism and comparing with experimental data.