能量重心法在电力谐波参数估计中的运用  

Application of energy centrobaric method in estimation for electrical harmonic parameters

作　　者：唐轶[1] 杨洛[1] 梁华洋[1] 陈奎[1] 

机构地区：[1]中国矿业大学信息与电气工程学院,江苏徐州221008

出　　处：《电力系统保护与控制》2012年第18期101-105,共5页Power System Protection and Control

摘　　要：提出了一种新的电力谐波参数高精度估计算法。该算法在对加窗信号进行FFT变换后,通过用窗函数的主瓣功率来代替加窗信号的功率,进而推导出频率和相位的估计公式;然后使用Parseval定理得出了幅值的估计公式。在此基础上分析了窗函数对谐波参数估计精度的影响,同时研究了多频率信号校正点数的选取原则。数值仿真试验表明,窗函数主瓣所占的能量越高,谐波参数的估计的精度也越高;和插值法相比,该方法计算耗时少,同时能有效地抑制白噪声的影响,很适合于嵌入式系统和DSP数字信号处理器实现,是一种很实用的算法。A new accurate estimation method of electric power harmonic parameters is presented. After the FFT transformation for windowed signals, the estimation formula of frequency and phase is derived by replacing the windowed signal power with main lobe of spectrum of window function. The estimation formula for amplitude is deduced from the Parseval theorem. And then the effect of window function on harmonics parameters estimation precision is analyzed, while research on the selecting principles of multi-frequency signal correction points is conducted. Numerical simulation experiments show the higher the energy of the main lobe of spectrum occupies, the higher the calculation accuracy of electric power harmonic parameters is; the algorithm takes less time compared with interpolation FFT, while with excellent performance of anti-noise, thus the practical algorithm is suitable for embedded system and DSP digital signal processors.

关 键 词：参数估计 FFT 窗函数 主瓣 抗噪性能 

分 类 号：TM935[电气工程—电力电子与电力传动] TM714