Switching Phenomena for EHV and UHV equipment

In 2009 and in 2011 CIGRE WG A3.22 had published the results of its studies on the requirements for UHV substation equipment (Technical Brochures 362 and 456). To complete these studies, WG A3.28 investigated more in depth the influence of a number of system parameters on the switching phenomena. The studies included UHV as well as EHV voltage classes and addressed specific questions raised by IEC TC 17, especially related with transformer limited faults. Benchmark simulations have been performed to compare the impact of the system parameters on circuit breaker switching phenomena. Experience with commissioning tests, field tests and field experience have been collected. By simulations the switching requirements for disconnectors, earthing switches and high speed earthing switches under various system conditions have been illustrated. The results contributed to the standardization work by IEC TC 17.