A new fault location method avoiding wave speed and based on traveling waves for EHV transmission line

The uncertainty of wave speed brings error to fault location based on traveling waves. The present fault location methods avoiding wave speed were based on single or double terminal traveling waves. However, invalidation or great error will occur when the attenuated waves can not be measured after refraction or reflection. Based on the basic theory of fault location, a new fault location method avoiding wave speed and transmission line radian is presented in this paper. By measuring the different time parameters when the initial traveling wave surge arrives at the reference bus, the opposite bus of fault line and the opposite bus of vicinal line, this method eliminates the influence caused by wave speed and radian of transmission lines from the expression of fault distance with use of the time parameters. The simulation shows the high accuracy and credibility of the method.