一种提高短时闪变严重度Pst计算精度的方法  

A method to improve calculating accuracy of the short term flicker severity P_(st)

作　　者：孙成发[1] 高辉[1] 

机构地区：[1]阿城继电器股份有限公司哈尔滨瑞雷电气科技发展有限责任公司,黑龙江哈尔滨150090

出　　处：《电力系统保护与控制》2008年第16期48-51,56,共5页Power System Protection and Control

摘　　要：短时闪变严重度Pst是IEC标准中衡量电能质量的一个重要指标。文中提出一种提高Pst计算精度的方法,方法核心在于利用插值算法对DFT(FFT)计算结果进行修正形成插值DFT(FFT)以克服DFT(FFT)存在的频谱泄漏和栅栏效应;提出应用BP网络对单位瞬时闪变值时频率和正弦电压波动值进行建模以提高二者的拟合精度。提出的方法不仅通过仿真试验得到验证而且在实际中得到成功应用。The short term flicker severity Pst is an important index of power quality in the standards of IEC. A method to improve the accuracy of Pst is proposed in this paper. The corn of this method is that, first, interploation algorithms is applied on revising the results of DFT （FFT） to overcome the disadvantage of spectral leakage and barrier effect, then, BP networks is employed on setting model of frequency and sin voltage fluctuation value at unit short term flicker to improve fitting accuracy. The proposed method to improve the accuracy of Pst is not only proved to be effective by simulation but also applied successfully in practice.

关 键 词：电能质量 闪变严重度 离散傅里叶变换 插值算法 BP网络 

分 类 号：TM744[电气工程—电力系统及自动化]