基于最小二乘法的电力系统谐波与间谐波检测方法

A method for power system harmonic and interharmonic detection based on least square method

为能够对电力系统中谐波与间谐波信号进行精确的检测,提出一种基于最小二乘法的谐波与间谐波检测方法。首先从数学理论和工程应用论证该方法在谐波与间谐波检测中的可行性。该方法用最小二乘法对被测信号进行函数拟合,通过拟合函数的系数实现谐波与间谐波的检测。通过对实际应用中典型信号的Matlab仿真表明,该方法能够准确检测谐波与间谐波分量的频率、幅值和相位角,且计算量较小。通过对标准IEC 61000-4-7中两种典型情况的分析表明,该方法能够为需要精确测量谐波与间谐波分量的场合以及未来IEC 61000-4-7的修订提供一种可选择的方法。

In order to make accurate detection for harmonic and interharmonic signal in power system, the paper presents a harmonic and interharmonic detection method which is based on /east-squares algorithm. First of all, the feasibility of this method is discussed by analysing mathematical theory and engineering application in harmonic and interharmonic detection. The detection of the harmonic and interharmonic is through coefficients of the fitting function and is based on least-squares algorithm. The Matlab simulation result of the typical signal shows that the frequency, amplitude and phase angle of the harmonic and inter-harmonic components can be detected accurately by the method, and the method has less calculation work. The analysis results of the two typical cases in the standard IEC 61000-4-7 show that the method can be an alternative in the situation when accurate detection is required. It also can provide a detection method for the amendment of the IEC 61000-4-7.