The influence of switching surges on impregnated capacitor paper insulation

The use of capacitors in electric networks is becoming more and more common. The capacitor remains under the voltage of the network, and in addition it is subjected to various over-voltages appearing in the network. The latter will originate from lightning strokes and more frequently from switching operations. Due to the incompleteness of data on the capacitor dielectric strength under switching surges, the problem became of interest. The lightning and switching surges may cause a weakening of the dielectric strength of many types of equipment. Power capacitors, with their impregnated paper insulation, belong to this category of equipment.