环境温度对CVT计量误差的影响  

Influence of ambient temperature on CVT’s measurement error

作　　者：杜林[1] 李永森 贺鹏[1] 陈斌 DU Lin;LI Yongsen;HE Peng;CHEN Bin(State Key Laboratory of Power Transmission Equipment&System Security and New Technology,Chongqing University,Chongqing 400044,China;Jiangbei Power Supply Bureau of State Grid Chongqing Electric Power Company,Chongqing 401147,China;State Grid Ningbo Power Supply Company,Ningbo 315000,China)

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400044 [2]国网重庆江北供电公司,重庆401147 [3]国网宁波供电公司,浙江宁波315000

出　　处：《电力自动化设备》2020年第6期204-209,共6页Electric Power Automation Equipment

摘　　要：电容式电压互感器(CVT)的计量精度易受到多种环境因素的影响,其中环境温度为主要的影响因素。温度变化会引起CVT电容分压单元的电容量与介质损耗因数发生改变,从而影响CVT的计量精度。采用仿真与试验相结合的方式研究了温度对220 kV CVT计量误差特性的影响规律。仿真和试验结果表明随着环境温度升高,CVT电容分压单元高、低压臂电容的电容量呈减小趋势,介质损耗因数呈先减小后增大的变化趋势。环境温度的升高会导致CVT的比差负向增大,角差正向增大。在温差大的地区,若CVT存在较大的初始误差,环境温度的变化将导致CVT存在超差的风险。The measurement accuracy of CVT(Capacitor Voltage Transformer)is susceptible to a variety of environmental factors,among which the ambient temperature is the main influencing factor.Temperature variation will change the capacitance and dielectric loss factor of the voltage dividing capacitors and further result in the measurement error of CVT.The influence of ambient temperature on the measurement error characteristics of 220 kV CVT is studied by simulation and experiment.The simulative and experimental results show that with the increase of the ambient temperature,the capacitance of the high and low voltage arms of CVT capacitor voltage dividing unit decreases,and the dielectric loss factor decreases first and then increases.The increase of ambient temperature will cause negative increase of CVT’s magnitude error and positive increase of angle error.The CVT with large initial error may have the risk of over tolerance in the areas with large temperature difference.

关 键 词：电容式电压互感器 误差特性 环境温度 精度 误差 

分 类 号：TM451.2[电气工程—电器]