摘要
采用快速傅里叶变换(FFT)进行电力谐波分析时,很难做到整周期截断和同步采样,导致频谱泄漏,无法精确得到电力谐波各参数。对采样信号进行加窗截断,用双谱锋线插值算法修正检测结果,可改善因非同步采样导致的频谱泄漏,提高检测精度。本文提出一种改进的余弦窗,分析其频谱特性,运用多项式拟合推导出简单实用的插值修正公式,减少运算量。仿真结果表明,加改进余弦窗双谱线插值FFT算法检测精度高,有效抑制了频谱泄漏。
There are difficulties in performing integral cycle truncation and synchronized sampling for fast Fourier algorithm in power harmonic analysis,thus result in frequency leakage,and the exact harmonic parameters can not be detected.The sampling signal is truncated by using cosine-window,then double-spectrum-line interpolation algorithm is used to correct the result,and compensate the spectral leakage caused by non-synchronized sampling to obtain high measurement accuracy.An enhanced cosine-window is proposed and its spectral characteristics are analyzed.The applicable correction formulas are obtained by fitting of polynomials and calculating burden is decreased.The simulation results show that the enhanced cosine-window interpolation FFT algorithm can control the spectral leakage efficiently and increase detection accuracy.
出处
《电气工程学报》
2016年第4期15-21,共7页
Journal of Electrical Engineering
基金
国家自然科学基金(51577046)
国防科技计划项目(C1120110004
9140A27020211DZ5102)
教育部科学技术研究重大项目(313018)
安徽省科技计划重点项目(1301022036)资助
关键词
快速傅里叶变换
谐波分析
同步采样
频谱泄漏
余弦窗
多项式拟合
Fast Fourier transform
harmonic analysis
synchronized sampling
spectral leakage
cosine-window
polynomial fit
