改进FFT非稳态电力谐波分析及应用  

Power System Harmonic Analysis under Nonstationary Situations and Its Application Based on Improved FFT Method

作　　者：曾博[1] 滕召胜[2] 周毅波[1] 

机构地区：[1]广西电网公司电力科学研究院,南宁530023 [2]湖南大学电气与信息工程学院,长沙410082

出　　处：《电工技术学报》2012年第11期256-262,共7页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(60872128)

摘　　要：在分析余弦函数窗频谱特性的基础上,建立基于余弦偶次幂窗改进FFT的谐波分析方法。运用最小二乘拟合法推导建立信号基波与各次谐波的频率、幅值和相位计算修正公式。仿真结果表明:提出的方法能有效克服基波频率波动以及间谐波的影响,谐波参数计算准确度明显提高,适合于非稳态条件下的谐波分析。嵌入式系统应用验证了算法的正确性。In this paper, the spectral characteristics of the cosine window are analyzed and an improved FFT method for harmonic analysis based on the even order cosine window （EOCW） is proposed. The rectification formulae of the frequency, amplitude and phase of the fundamental and harmonics are obtained by using the least squares fitting method. Simulation results indicate that, the precision in calculating harmonic parameters can be highly improved by the proposed algorithm, no matter with the fundamental frequency varies and the presence of interharmonics. The proposed algorithm is suitable for harmonic analysis under nonstationary situations and the correctness of which is verified by the application in embedded system.

关 键 词：谐波分析 非稳态 改进FFT 余弦偶次幂窗 

分 类 号：TM935[电气工程—电力电子与电力传动]