Power line vicinity monitoring via multiple displacement current measurement

Developing sensing technologies to measure and characterize local Electromagnetic field (EM) signatures around overhead line conductors has become an appealing solution to successfully implement a low-cost, distributed and massively deployed power line sensor network (PLSN) for power grid monitoring. Such sensing technologies potentially assess the local healthiness of power lines and to predict incipient faults of lines, such as proximity of tree limbs, or violation of conductor-to-ground clearance. This kind of information is normally not available to conventional fault detection devices. This paper proposes a novel Multiple-Displacement-Current-Sensor (mDCS) to capture the spatial mapping of the electric field (E-field) distribution around overhead line conductors. In stead of considering total induced equivalent electric charge, the distribution of the electric charge density induced on the mDCS surface is analyzed. A DQ-axis decomposition technique is applied to separate the capacitive coupling effects to the mDCS from adjacent conductors in different directions. The decomposed DQ-axis components have potential to enable independent measurement of conductor-to-ground clearance and overhead conductor voltage. Simulation results are presented to validate the proposed idea.