Influence Mechanism of Hot-Press Setting Time and Winding Tension on the Performance of Metallized Film Capacitors

Metallized film capacitors are key power equipment in flexible direct transmission systems, pulse power systems and electric vehicles, and their application performance directly affects the stability and reliability of power grid systems and users. This article investigates the effects of hot-press setting time and winding tension control on capacitor performance during the manufacturing process of capacitor elements in durability tests. At a certain temperature, the setting of the hot-press setting time of the capacitor element and the winding tension setting of the element can eliminate the residual stress inside the metallized film element, make the dielectric film produce irreversible heat shrinkage, eliminate the moisture and air in the metallized film element through the film shrinkage and physical compression force to compress the element, reduce the probability of air discharge inside the metallized film, and improve the internal breakdown strength and partial discharge starting voltage of the element. Therefore, according to different performance requirements, choosing a certain hot-press setting time and winding tension is conducive to improving the service life of metallized film capacitor.