适用于微机定时交流采样的改进富氏算洁

AN IMPROVED FOURIER ALGORITHM SUITED FOR MICRO-COMPUTER FIXED TIME ALTERNATING CURRENT SAMPLING

基于富里叶变换的微机交流采样计算方法在电力系统中已得到了广泛应用。根据富里叶变换可以很方便地计算出电压或电流的基波分量有效值，以及计算出有功、无功等电气量。然而当采样周期有误差时，则计算结果有较大误差。本文分析了产生误差的原因，并提出了新算法。算例表明，新算法具有较高的精度，适用于微机定时采样。因此，本文提出的微机交流定时采样和新算法在电力系统自动控制和智能化仪器、仪表等方面有广泛的应用前景。

Based on Fourier transform the computationmethod of AC sampling adopted in micro-computer systemis used widely in power system. By Fourier transform it iseasy to calculate the effective value of fundamental voltageand current. From this, the value of active and reactivepower can be obtained. If the sampling period is not accurate,there will be errors in the results of calculation. Inthis paper the authors analyze the reasons causing the calculation errors, and put forward a new algorithm for periodicAC sampling. The result of calculation example indicatesthat the algorithm is of higher precision and is suitable forautomatic control system and intelligent measuring apparatus in power system.