Capacitor Switching in APFC Panels

Capacitor switching is a critical task in APFC panels because of the high inrush current taken and voltage transients initiated by capacitors at the time of switching. The switching device should be able to withstand both inrush current and voltage transients, along with the ability to carry rated capacitor constantly. Capacitor duty contactors and Thyristor Switching Modules are two major devices used for capacitor switching. These can be either manually or automatically operated.

Details about the two types of capacitor switching methods are discussed in this article.