Mitigation methods to improve the lightning performance of hybrid transmission line

Abstract

EMTP simulations and lightning attachment models are performed to estimate backflashover performance of multi-circuit transmission tower. Multi-circuit transmission tower has several systems on the tower and combines DC transmission over long distances with more flexible AC transmission. The outcome of simulations and calculations should give the range of backflashover withstand current and backflashover outage level. Maximum lightning current amplitude that does not cause backflashover across insulator string is estimated in response to first and subsequent strokes several flashover models. The paper presents a new unbalanced design of insulation. Latter should decrease backflashover rate for lines serving critical loads like HVDC lines.