ARCING TRANSIENTS ON MULTI-CIRCUIT LINES

Abstract

In several cases transmission line circuits with different nominal voltage levels run in parallel on same towers. Becomes faulty the lower voltage (HV or MV) circuit it initiates a Single or Three Phase Reclosing (SPR or TPR) during which the higher voltage (HV or EHV) circuits could cause a low current (secondary) arc in the ionized plasma cloud generated by former primary fault arc as a consequence of coupling with healthy phase conductors. Does not extinguish secondary arc till the faulty phase(s) reclosing SPR or TPR will be inefficient. One goal of the paper is to study electromagnetic transients during dead time of the AR (Automatic-Reclosing) by simulation. Besides the author has invented and built a HV test circuit from lumped components to analyse above-mentioned phenomena. Article shows main results having got by simulation and confirmed by actual HV tests as well as a plan of another HV circuit by means of which real network circumstances can be simulated correctly. Inductive potential transformers and ZnO surge arresters are not disconnected from faulty phase during AR. Analyzing influences by these units on studied phenomena has been also carried out.