The organization of metrological channels for fault location on overhead lines based on phasor measurement units

The practical implementation of phasor measurement unit (PMU)-based fault location in high-voltage overhead lines presents a number of difficulties including the significant impact of DC components in the current waveform and residual magnetization in the current transformer. Synchrophasor measurement technology was only meant to capture steady states and electromechanical transients. The issues mentioned above indicate the need for significant changes in the measurement of synchrophasor-based fault location. This paper investigates the efficiency of various current measurement configurations for fault location purposes in an extra-high voltage overhead line using synchrophasor measurements. The main goal of this research is to identify the optimal current measurement configuration for phasor-based fault location and to assess the possibility of using digital current transducers with built-in Rogowski coils to reduce the effect of current transformer saturation on fault location accuracy. The research methodology involves extensive use of a real-time digital simulator (RTDS), production-type PMU devices from various vendors, and signal amplifiers, with the main focus on improving the fault location accuracy in overhead transmission lines. A few well-known double-end fault location methods utilizing different voltage and current components are taken for numerical experiments. The results show the importance a new measurement paradigm based on applying innovative instrument transducers to provide input signals for synchrophasor applications. A clear advantage of class-P PMUs connected to the relay coils of current transformers for fault location purposes is shown. Several measurement channel configuration approaches are compared in terms of their performance in the context of phasor-based fault location.