DIGITAL SIMULATION OF EHV SYSTEMS UNDER SECONDARY ARCING CONDITIONS ASSOCIATED WITH SINGLE-POLE AUTORECLOSURE.

The effectiveness of single-pole autoreclosure (SPAR) in maintaining power-system stability is largely determined by the speed with which secondary arc extinction, and hence autoreclosure, can be achieved. Realistic simulation techniques are of importance in relation to the design of systems employing SPAR. Digital methods are developed to enable the faulted response of feeders, subjected to secondary arcing phenomena, to be simulated. The new techniques are important in relation to programmable based protection test equipment. Based upon experimental data, methods of modelling the nonlinear behavior of the ground-fault arc path, in both conducting and extinction states, are described, togeter with techniques developed for incorporating such models into practical system interconnections. Results of a computational sudy relating to a typical short 500 kv feeder employing SPAR are discussed.