Novel sensing of utility currents along transmission line spans

Abstract

Some experimental and computational efforts to sense Line Currents (IL), Air Charging Currents (ACC) & Leakage Currents (ILK.), which are normally associated with the High Voltage (HV) utility power systems, are exerted. The low cost Giant Magneto Resistive (GMR) sensors are successfully manipulated to measure very large values of IL. GMR manipulations such as distance and angle alterations are performed in order to prevent magnetic saturation and remain in linear ranges. In parallel, a Nonmagneto Equipotential Capacitive (NEC) sensor is constructed in laboratory to measure discrete values of ACC & ILK. The designed NEC prototype is to be installed and remotely controlled along the most critical Transmission Line (TL) spans. Accurate measurements of IL, ACC & ILK are utilized to estimate other electrical and mechanical quantities, such as HV, Sag and Conductor surface Temperatures. Measurements of IL, ACC & ILK are also utilized to implement certain sophisticated protection & control schemes, such as Dynamic-Line-Ratings (DLR). Unlike the existing methodology of sensing AC circuits only, our proposed sensing is applied indiscriminately to both AC and DC circuits. The primary experimentation, simulation and estimation have proved the basic concept and fusibility of the proposed method.