This paper reports for the first time on the performance of a 345 kV optical current sensor used for substation metering. The waveform quality of this sensor was compared to a conventional current transformer in both the time and frequency domains. In addition a demonstration to interface this device with conventional five ampere protective relay systems, using a pulse width modulation amplifier will also be discussed. The optical current sensor is based on the Faraday Effect. This unique system was designed and developed to advance the state of the art in optical metering, relaying, and in data acquisition. The system has advanced the design of fiber optic high voltage column technology by utilizing a light weight polymer column, which provides a graded voltage path for the optical fibers from the high potential bus to the ground plane. A unique fiber optic technique was incorporated into the system to measure bus movement under normal operating conditions as well as fault conditions. A sophisticated data acquisition system was also developed, with remote programming and interrogation capabilities, that can monitor and store various power quantities and system performance data. Signal processing software is then utilized to thoroughly evaluate and analyze the data. The decisions leading to the design of the optical metering system, the components of the system, the site installation, field test results, and recommendations for future work, will all be discussed.
