Measuring line currents remotely

Abstract

This paper describes an innovative new technology for measuring currents in medium and high voltage power lines at a safe distance from the wires. The instrument can be installed outside the 'hot zone' around the wires. It measures the current in each individual wire in real time and can feed this information to a range of backend applications. A full description of the currents in an overhead line is embedded in the magnetic fields in the vicinity of the line. We can decode this information by measuring the magnetic fields and wire geometry at a position near the line. Initial applications include load recording and power quality monitoring. Stand-alone instruments can link to automation systems over communication links. This technology can help leverage the powerful communications and digital processing technologies now available by providing a current interface for high voltage networks.