Распознающая способность локальных токов при двухстороннем наблюдении линии электропередачи

Abstract

The article is devoted to information factors contributing to the recognition of the fault location in the power line, and if there are several branches, it is possible to identify the damaged branch. Relay protection algorithms widely use the separation of short-circuit current into the previous and emergency components. The latter carries basic information of the fault location. Recently, it was found that the emergency component, in turn, can be divided into two components, which are called normal and local. The local component is of particular information value, since the ratio of local currents shows a strong dependence on the fault location or on the damaged branch, but does not depend on the fault current and, most important, on the part of the electrical system external to the observed line. The influence of unobserved branches on the accuracy of determining the location of damage by the proposed measurement is analyzed. Attention is drawn to the correspondence of the local currents algorithm to the emerging tendency to unify the characteristics of relay protection and automation.