Improvement of distance protection algorithms based on phasor measurements

Abstract

Distance protection of overhead lines is widely used and is continually being improved. However, the distance protection cannot work stably and is blocked in several electromechanical transients. Additionally, a non-linear arc can affect the stability of the distance protection in case of a short-circuit. The authors consider ways to improve distance protection during such transients. In particular, this paper proposes the use of synchronized phasor measurement technology to improve the efficiency of distance protection. This paper considers a new approach for the analysis of electromechanical and electromagnetic transients in a power system using process synchrophasors. As examples, cases of a short-circuit in a line with oneway and two-way powers are considered. The authors consider the influence of a non-linear arc at the fault point and consider the possibility of the coincidence of the electromechanical and electromagnetic transients. The result is a new algorithm for operating distance protection, an improvement in the parametric method for determining the location of line damage. The calculations performed and mathematical modeling confirm the effectiveness of the proposed algorithm.