Overvoltage caused by switching operation - a threat to SPDs

Abstract

Surge protective components (SPDs) are today an important component of overvoltage protection systems. Also, in the case of a lightning event, an uninterrupted and safe power supply is expected. The steadily increasing number of electronic devices and their growing sensitivity against overvoltages require surge protective devices (SPDs), which are able to guarantee the equipotentialisation in case of a lightning event as wel as an overvoltage protection in the case of switching operations. The low protection level may cause a huge number of possible operations of the SPD. The components used in modern SPDs stand out for their high capacity and simultaneously good protective properties. New challenges resulting from new installation requirements, like the increased application of inverters, fluctuating and restricted short-circuit capacity and more instable network conditions, require in future different and higher demands on SPDs.