Research on Thermal Aging Performance of Capacitor Component Made of Metallized Film

The DC-link capacitor is a core part of converter, and the complex operating environment puts forward strict requirements on its durability. High temperature contributes significantly to its aging. In this paper, the metallized film capacitor component is taken as the research object, which is the basic structural unit of DC-link capacitor. Aiming at the high temperature operating conditions faced by DC-link capacitors, the variation of performance parameters with time at different temperatures is experimentally studied. The results show that under the thermal aging, the capacitance of capacitor components will increase in the early stage of aging test, then decrease slightly with the aging time, and finally remain basically unchanged. As for the equivalent series resistance value of the capacitor components, when the aging temperature is 85 °C, the resistance value will increase rapidly in the early stage of aging, then enter a stable state. When the aging temperature exceeds 100°C, the equivalent series resistance value will experience a sudden increase in the rising rate after a short and slow increase, and finally return to a slow increase again.