实现配电网PMU频率测量的数字微分器研究  

Design of Digital Differentiator for Frequency Measurement in Distribution Grid PMU

作　　者：张琳 任双雪 惠子珈 汪芙平[2] 刘书翔 ZHANG Lin;REN Shuangxue;HUI Zijia;WANG Fuping;LIU Shuxiang(State Grid Shaanxi Electric Power Company Economic Research Institute,Xi'an 710075,Shaanxi Province,China;State Key Laboratory of Power System and Generation Equipment(Tsinghua University),Haidian District,Beijing 100084,China)

机构地区：[1]国网陕西省电力公司经济技术研究院,陕西省西安市710075 [2]电力系统及发电设备控制和仿真国家重点实验室(清华大学),北京市海淀区100084

出　　处：《中国电机工程学报》2021年第22期7640-7647,共8页Proceedings of the CSEE

基　　金：国家自然科学基金项目(52077112)。

摘　　要：与装配在主干电网的同步相量单元(phasor measurement unit,PMU)相比,配电网PMU在进行频率测量时,除了无法利用对称的三相信号之外,还面临更高强度谐波和噪声的干扰。该文针对配电网PMU测量具体特点,研究低通数字微分滤波器的优化设计,通过对单相信号相位进行滤波实现频率测量。优化设计目标是,在低频段获得高精确度微分运算频响特性同时,强化中高频段对相位误差中各次谐波的有效抑制,并最小化噪声增益。通过对含约束优化问题求解,实现了长度为1.0~1.5工频周期的线性相位有限冲激响应(finite impulse response,FIR)数字微分器设计。仿真结果表明,所设计滤波器与IEEEC37.118.1相量测量参考算法配合,可以在静态和动态配电网环境下实现频率的快速精确测量,具有较高的工程应用价值。As compared to the phasor measurement units(PMU) installed in power grids transmission line, the PMUs in distribution level have to perform single measurement, and suffer from stronger harmonics and noise pollution. In this paper, the low-pass digital differentiator was optimally designed for PMU frequency measurement in distribution level.The optimal digital filter aimed to possess ideal differentiator frequency response within phasor frequency band, and to gain perfect harmonic suppression and minimized noise in high frequency band. By solving well-defined constrained optimization problems, the linear phase finite impulse response(FIR) digital differentiators were designed with the filter lengths from 1 nominal fundamental cycle to 1.5 cycles. The simulation results shows that the designed filters, working after the synchrophasor estimator recommended in IEEE C37.118.1,perform fast and accurate frequency measurement both in steady and dynamic conditions in distribution level.

关 键 词：频率测量 同步相量测量单元 配电网 最优滤波器设计 

分 类 号：TM76[电气工程—电力系统及自动化]