基于电场诱导二次谐波效应的非侵入式电场测量方法及系统  

Non-intrusive Electric-field Measurement Based on Electric-field Induced Second Harmonic Generation:Principle and System

作　　者：崔英哲 庄池杰[1] 曾嵘[1] CUI Yingzhe;ZHUANG Chijie;ZENG Rong(State Key Laboratory of Control and Simulation of Power System and Generation Equipment,Department of Electrical Engineering and Applied Electronics,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学电机工程与应用电子技术系电力系统及发电设备控制和仿真国家重点实验室,北京100084

出　　处：《高电压技术》2021年第12期4177-4190,共14页High Voltage Engineering

基　　金：国家自然科学基金(52022044)。

摘　　要：电场测量是研究气体放电的关键,在高电压领域具有较为广泛的需求,传统的侵入式电场测量会畸变电场。为此自主建立了基于电场诱导二次谐波原理的空间电场测量系统,该效应的电场测量系统具有非侵入式、不受气体环境限制、高空间和时间分辨的优点。考虑激光能量空间分布和待测电场分布,提出了二次谐波效应自洽模型,验证了模型的正确性。从理论及实验两方面,研究了二次谐波信号强度与入射激光偏振方向、光路聚焦参数之间的关系,讨论了平面波近似模型的适用范围。通过优化光路结构、调节透镜强聚焦结构、提高激光功率的方式,提高了系统灵敏度,已实现的系统的最小可测电场为0.4 kV/cm,最小空间分辨率达毫米级。Electric-field measurement is critical to the investigation of the air gap discharges.The traditional electric-field measurement is intrusive,which may distort the electric field.Therefore,an electric-field measurement system based on electric-field-induced second harmonic generation(EFISH)is set up.The electric field measurement system based on this principle has the advantages of being non-intrusive,not restricted by gas environment,high spatial and time resolution.Moreover,a self-consistent model of the EFISH process is established.The correctness and effectiveness of the proposed model are verified.The spatial distribution of laser field and electric field to be measured are taken into consideration,and the effects of the polarization direction of the laser and the focusing parameters on the second-harmonic signal are studied by simulations and experiments.The working conditions of the plane-wave approximation model is analyzed.The system’s sensitivity is improved by optimizing the optical path,adjusting the Rayleigh range of the laser,and increasing the laser power.It can be realized that the minimum measurable electric-field is 0.4 kV/cm,and the minimum spatial resolution is in mm-grade.

关 键 词：非侵入式电场测量 电场诱导二次谐波效应 自洽模型 测量性能 电场测量系统 

分 类 号：TM937[电气工程—电力电子与电力传动]