The new method of determining characteristics of elements for overvoltage protection of low-voltage system

This paper presents an innovative method for an efficient characterization of relevant characteristics of nonlinear overvoltage protection elements in low-voltage applications. Standard measuring equipment was modified to enable an efficient and repeatable experimental procedure in order to investigate characteristics of overvoltage diodes and varistors, in particular volt-ampere characteristic, volt-ohm characteristic, coefficient of nonlinearity, and dissipating energy. Furthermore, the pseudoempiric method using the "area law" has been developed to determine a pulse characteristic of a gas-filled surge arresters (GFSA). An innovative aging estimate algorithm was additionally used. The justification of the suggested method on commercial nonlinear overvoltage components was checked. Its protective characteristics were examined by both the classical approach and the new suggested method. The obtained results from both methods showed minimal discrepancies.