Limitations of Traveling Wave Fault Location

Abstract

The estimation accuracy of traveling waves (TWs) arrival times, caused by a short circuit on the power line, to the installation location of the fault locator and, therefore, the ability to determine the fault location (FL), is largely determined by the level of the front of the TWs themselves: the lower TW level, the more difficult it is to recognize it. In this connection, it is obvious that it is necessary to calculate the power system regimes to determine the TW fronts values to estimate the TW fault location feasibility in a particular electrical network. When installing the TW fault locator, usually are compare the characteristic impedance beyond the bus with the characteristic impedance of the transmission line: if the first is less than the second preference is given to measuring current. Vice versa- preference is given to measuring the voltage. However, the existing methods do not take into account the influence on the TW value of the power system elements located between the short circuit and the locator and, like the characteristic impedance beyond the bus, which can significantly reduce the TW value. This approach can lead to the installation of the locator in the network, where it will be completely useless due to the insufficient for measurement TWs values. The purpose of this article is to determine the limitations of TWFL methods based on an analysis of TW front values for different network configuration and voltage classes.