基于Fourier级数的相位差算法在MOA检测中的应用  

An Algorithm of Phase Difference Measurement Based on Fourier Series with Application in Detection of MOA

作　　者：王又佳[1] 段大鹏[1] 江秀臣[1] 曾奕[1] 盛戈皞[1] 

机构地区：[1]上海交通大学电气工程系,上海200240

出　　处：《高压电器》2009年第4期142-145,149,共5页High Voltage Apparatus

摘　　要：MOA阻性电流检测的关键在于电压基波分量与泄漏电流基波分量相位差的检测。在分析现有相位差检测算法的基础上,应用Fourier级数分解方法与线性空间中正交向量内积为零的特性,推导出了一种新的相位差检测算法。该算法首先分别求得电压基波分量与泄漏电流基波分量的相位角,进而将两相位角相减即可求得相位差,并给出了该算法的离散化计算公式。该算法的正交运算同时可以将信号中的高次谐波与白噪声滤除。最后通过仿真分析了A/D量化位数、采样频率与电压频率波动对该算法测量精度的影响,并通过MOA实测与计算验证了该算法的正确性与有效性。该算法无需确定过零点,克服了电网谐波的影响,且计算精度高,易于实现。The key to the detection of MOA resistive current is the detection of the phase difference between fundamental component of voltage and fundamental component of leakage current. Based on the analysis of conventional phase difference detection method, a new algorithm of phase difference detection is presented according to Fourier series decomposition method and the characteristic that inner product of two orthogonal vectors in a linear space is zero. The algorithm calculates the phase of fundamental component of voltage and the phase of fundamental component of leakage current, respectively, and then calculates their difference. Furthermore, the calculation principle and discrete calculation formula of the algorithm is introduced. Higher-order harmonic and white noise can be suppressed and filtered simultaneously by the orthogonal calculations in the algorithm. Correctness and validity of the algorithm are verified through simulation and MOA resistive current test. This algorithm is simple to implement without determininge the crossing zero point, and can remove the interference of harmonic voltage in calculation with a high precision.

关 键 词：FOURIER级数 线性空间 正交向量 相位差检测 MOA阻性电流 

分 类 号：TM933.312[电气工程—电力电子与电力传动]