Design of a novel optical voltage sensor for ultra-high voltage application

A novel optical voltage sensor for ultra-high voltage measurement is proposed in this paper. The sensor is based on the converse piezoelectric effect of quartz. The piezoelectric deformation of the quartz crystal induced by an applied alternating voltage is sensed by an electrophotonic detector. To measure the small piezoelectric deformation, an optical-beam-deflection method is presented and the corresponding optical path parameters are analyzed. Also, a multi-loop optical arm embedded in two parallel plates is presented. The optical path is dependent only on the height of the parallel plates and the laser incident angle and is independent of the width of the parallel plates, which facilitates the structural design of the sensor. Furthermore, a precision photoelectric conversion circuit is designed to convert the optical signal to electric voltage. According to the designed signal processing circuit, the ultra-high voltage sensor (500KV) is able to achieve an accuracy class of 0.1.