MV faulted section location in distribution systems based on unsynchronized LV measurements

Abstract A medium voltage (MV) faulted section location technique depending solely on unsynchronized low voltage (LV) measurements in distribution systems is introduced in this paper. The proposed method identifies the faulted MV feeder segment when an unsymmetrical MV fault occurs. It exploits parameters including voltage magnitude, angle and sequence components captured via distributed non-synchronized monitoring devices connected at secondary substations. In this study, the characterization of a system’s LV profile during MV faults was achieved throughout both software simulations and physical testing. The latter was conducted in the 11 kV and LV distribution network of the Power Networks Demonstration Centre (PNDC) of the University of Strathclyde. The tests were performed for both 11 kV radial and ring network configurations. Modelling and simulations implemented using the DigSILENT PowerFactory package, complemented the hardware level testing and provided the opportunity for further examinations, such as the impact of MV laterals connection, distributed energy resources on both MV and LV side as well as the presence of unbalanced loads. Finally, the paper evaluates the effectiveness of the proposed faulted section location technique under various physical and simulated fault scenarios, loss of communications and noise interference.