摘要
带外干扰和基波频率偏移同时存在并且相互影响使得频率测量算法精度急剧下降,提出考虑带外干扰的电力系统频率测量算法对该问题进行处理。算法首先分析基波频率偏移和带外干扰同时存在的泄漏关系,通过离散傅里叶变换(discrete Fourier transform,DFT)来获得粗略的带外相量值;其次利用带外相量值计算带外粗估频率,并将其反馈给拓展后的泰勒模型作为基准频率参与运算;最后利用模型中的泰勒高阶导数获得精确的频率测量值。仿真结果表明,提出的算法在频率偏移和噪声工况下能够分别给出精度较高的基波频率值和带外频率值;录波数据测试表明,算法能够准确给出实时信号的频率测量值且该值具有较小的波动性,证明了算法的综合性能。
Out-of-band interference and fundamental frequency deviation decreases accuracy of frequency estimation sharply, so that a frequency estimation algorithm of power systems considering out-of-band interference was proposed to solve this problem in this paper by modeling frequency deviation of fundamental component and out-of-band interference. Firstly, leakage phenomenon is analyzed considering out-of-band interference and fundamental frequency deviation, and a rough out-of-band phasor is obtained by reassigning phasor estimation of discrete Fourier transform(DFT). Then, the rough phasor was utilized to calculate rough out-of-band frequency, treated as the reference frequency of the expanding Taylor model. Finally, according to the higher-order derivatives of Taylor model, accurate frequency estimation could be obtained. Simulations show that the proposed algorithm can accurately yield both fundamental frequency and out-of-band frequency under frequency deviation and noise disturbance. The power-system-voltage test illustrates that the proposed algorithm can provide frequency estimations with smaller fluctuation than that of the algorithms in comparison.
作者
白莎
潘晨玥
熊思宇
符玲
BAI Sha;PAN Chenyue;XIONG Siyu;FU Ling(College of Electrical Engineering,Southwest Jiaotong University,Chengdu 610031,Sichuan Province,China)
出处
《电网技术》
EI
CSCD
北大核心
2019年第3期761-768,共8页
Power System Technology
基金
国家自然科学基金面上项目(51777173)
四川省科技计划项目(2018GZ0014)~~