基于分段加Nuttall窗插值FFT的电压暂降检测方法  

Voltage Sag Detection Method Based on Segmented Interpolation FFT with Nuttall Window

作　　者：徐勇 向运琨 曾麟 何哲 XU Yong;XIANG Yunkun;ZENG Lin;HE Zhe(State Grid Hunan Integrated Energy Service Co.,Ltd.,Changsha 410007,China)

机构地区：[1]国网湖南综合能源服务有限公司,湖南长沙410007

出　　处：《自动化仪表》2021年第9期54-60,共7页Process Automation Instrumentation

摘　　要：电压暂降是目前各种电能质量问题中,发生频次较多、影响较大的一种。为实现电压暂降的快速准确检测,提出了一种基于分段加Nuttall窗插值快速傅里叶变换(FFT)的电压暂降检测方法。该方法首先通过对原始电压暂降信号进行求导和平方和运算,以进行暂降起止时刻、持续时间的获取以及暂降稳定区间的划分;而后对稳定区间内信号采用加Nuttall窗插值FFT运算,以得到暂降幅值和相位跳变等特征量。仿真试验和实际构建的硬件测试平台验证了所提方法的可靠性和有效性。与现有检测方法相比,所提方法计算量小,在快速检测电压暂降特征量的同时,还具有准确度高、不易受谐波与噪声干扰等优点。所提方法对于电压暂降敏感设备特征分析、类型划分以及暂降监测、评估和治理具有重要意义。Voltage sag is one of the most frequent and influential power quality problems at present.In order to realize the rapid and accurate detection of voltage sag,a voltage sag detection method based on segmented interpolation fast Fourier transform(FFT)with Nuttall window was proposed.Firstly,the original voltage sag signal is derived,and the sum of squares is calculated to obtain the start,stop time and duration of sag and to divide the sag stability interval.Then,interpolation FFT with Nuttall window is applied to the signals in the stable interval to obtain characteristics,such as sag magnitude and phase jump.The reliability and effectiveness of the proposed method are verified by the simulation experiment and the actual hardware test platform.Compared with the existing detection methods,the proposed method has the advantages of less computation,high accuracy and less interference by harmonics and noise,as well as rapid detection of voltage sag characteristics.The proposed method is of great significance for the characteristic analysis,classification,monitoring,evaluation and management of equipment which is sensitive to voltage sag.

关 键 词：电压暂降 区间划分 双谱线插值快速傅里叶变换 Nuttall窗函数 多项式拟合 特征量提取 相位跳变 

分 类 号：TH-743[机械工程]