Design and Application of Optical Voltage and Current Sensors for Relaying

Optical voltage and current sensors offer several benefits for use in high-voltage substations. Interface to relays and other secondary devices is one of the key issues when using optical sensors. Low energy analog interfaces provide an effective way for connecting optical sensors to relays. In this paper, several examples and applications of optical sensors connected to relays and recorders using low and high energy analog interfaces are discussed. In all cases, the performance of the entire system has been satisfactory. Lessons learned in these applications are also discussed