An Optimization-based Non-contact Transient Voltage Measurement Method by Integrated Optical Electric Field Sensor

Transient overvoltage in power systems, caused by lightning or switching, are a critical reliability constraint. Traditional contact measurement methods have limitations, prompting the development of non-contact measurement technologies. Integrated Optical Electric Field Sensor (IOES), based on Pockels effects, offers broad advantages for non-contact voltage measurement. This paper introduces an optimization-based decoupling method for multi-phase coupling scenarios in power system such as three-phase transmission lines and verifies its correctness with a non-contact transient voltage measurement system using IOES. The method involves obtaining a simulation decoupling matrix and then finding the “closest” matrix under constraints using optimization techniques. The decoupling results by the optimization-based method outperformed the simulation method in accuracy, demonstrating the effectiveness of the proposed method for non-contact voltage measurement in AC power systems.

I. Introduction

In today's power system, the transient overvoltage caused by lightning or switching operation has gradually become one of the most important factors restricting the reliable operation of the power system [1]. Therefore, the measurement of transient overvoltage becomes increasingly critical. Limited by the level of sensors, the current transient overvoltage measurement technology is still relatively traditional. Various contact measurement technologies such as voltage dividers, bushing end screens, GIS sensors, etc. dominate the application [2] –[4]. They have many limitations such as insufficient frequency bandwidth, narrow measuring range, bulky size, and excessive maintenance costs. Therefore, it is necessary to develop non-contact transient overvoltage measurement technology [5].