Degradation Analysis of The Metallized Film Capacitance under Various Conditions in EV Applications

The DC-link film capacitor is an essential part of the traction inverters in electric vehicles. This paper focuses on DC-link capacitor degradation under different working conditions. A DC-link film capacitor was tested under three different voltage and temperature conditions until the capacitance dropped below 90% of the initial value. A two-stage capacitor degradation model is proposed to describe the capacitance decrease for EV applications. The experimental results verify the effectiveness of the proposed capacitor degradation model.