DETERMINING TEMPORARY OVERVOLTAGE LEVELS FOR APPLICATION OF METAL-OXIDE SURGE ARRESTERS ON MULTIGROUNDED DISTRIBUTION-SYSTEMS

This paper provides an evaluation of different analytical methods that may be used to calculate values of temporary overvoltage on multigrounded distribution systems as a result of single line-to-ground faults. The methods are evaluated in terms of their general accuracy, their ability to account for changes of earth resistivity, ground electrode resistances and grounding frequency, and also in terms of the overall impact of such changes on the calculated overvoltage level. Recommendations are provided for the use of these methods under different sets of system conditions. © 1990 IEEE