非接触式电压相量测量算法  

Non-contact measurement method for voltage phasor

作　　者：李嘉贤 刘灏 毕天姝 LI Jiaxian;LIU Hao;BI Tianshu(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University),Beijing 102206,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京102206

出　　处：《电力工程技术》2023年第3期168-178,共11页Electric Power Engineering Technology

基　　金：国家自然科学基金资助项目(51725702)。

摘　　要：同步相量测量技术为电网动态安全监测提供了数据基础,非接触式电压传感技术具备安全、便捷、成本低的优势,有利于测量装置实现海量布点。现有非接触式电测量的缺陷在于复杂电压经探头传变后二次侧输出电压发生畸变,难以还原一次侧电压相量。为解决电压畸变问题,文中提出了一种对带内信号分频计算的相量测量算法。首先对探头输出电压进行预处理,滤除带外信号与噪声,随后采用矩阵束法计算带内信号频率,以此构建信号模型进行时域拟合求解带内信号相量,最后将带内信号相量还原至一次侧后合成得到综合相量。仿真结果表明,所提方法能够利用探头二次侧输出电压采样值计算一次侧电压相量。实验数据显示所提方法的幅值测量误差小于4.5%,相位误差小于1°,频率误差小于0.04 Hz,频率变化率误差小于4 Hz/s。The synchronous phasor measurement technology offers data for dynamic security monitoring in power systems.The non-contact voltage sensing technology has the advantages of safety,convenience and low cost,which is helpful for massive distribution of measurement devices.The defect of the existing non-contact voltage measurement technology is that the voltage probe may cause voltage distortion,and it is difficult to figure out the primary voltagephasor.In order to solve the problem of voltage distortion,the distortion law of voltage is revealed by analyzing the non-contact probe′s equivalent circuit and transmission characteristic,and a phasor measurement algorithm for each in-band signal is proposed.Signal pre-processing is used to filter the out-of-band signals and noise first;The matrix pencil method is used to calculate the in-band signal′s frequencies,which is used to build signal model,then the in-band signal phasors are figured out by fitting in time-domain;Lastly,the secondary phasors are restored to obtain the primary in-band signal phasors and synthetical phasor.The simulation results show that the proposed method can figure out the primary voltage phasor by using the sample of the probe output voltage.Experiment data show that the amplitude measurement error is less than 4.5%,the phase error is less than 1°,the frequency error is less than 0.04 Hz,and the frequency change rate error is less than 4 Hz/s.

关 键 词：同步相量测量算法 非接触式电压测量 电容耦合式电压探头 测量频带提取 矩阵束法 最小二乘法 

分 类 号：TM933.2[电气工程—电力电子与电力传动]