Fault Location for Three-Ended Ring-Topology Power System Using Minimum GPS-Based Measurements and CVT/CT Sensing

This paper presents a fault location technique for homogeneous ring-topology power transmission systems using synchrophasors sensed from the instruments in the power Internet of Things (IoT), such as Global Positioning System (GPS) based Phasor Measurement Units (PMUs) or Intelligent Electronic Devices (IEDs) with embedded GPS. Moreover, with a view to reducing the influence of measurement errors on fault location estimation, minimum demands for GPS-based equipment and Capacitor Voltage Transformer (CVT)/Current Transformer (CT) transducers are also considered when deriving the proposed algorithm. A unique fault locator is thus developed to recognize the faulted line branch as well as pinpoint the fault position at the same time. Not only can the proposed method avoid iterative operations, but it is also free from the problems of multiple solutions, fault type selections, and fault-path/source impedance assumptions. Last but not the least, extensive simulations considering 161 kV overhead-line parameters of Taiwan Power Company (Taipower) and actual non-ideal sensing/measurement phenomena are conducted to demonstrate the performance and effectiveness of the suggested idea.