摘要智能变电站是采用先进、可靠、集成和环保的智能设备,以全站信息数字化、通信平台网络化、信息共享标准化为基本要求,自动完成信息采集、测试、控制、保护、计量和检测等基本功能,同时,具备支持实时电网自动控制、智能性调节、在线分析与决策和协同互动等功能的变电站。现在,智能变电站在电网中运用的越来越多,需要测量系统能准确的测量出相位以便能够进行后续观测,但是采样得到的数据在传输中存在着不确定的延时性,因此,采取合理准确的算法进行相位测量有着很重要的作用。 83917
本文对比分析了一些在工程上常用相位测量算法的的优缺点,针对直接运用FFT分析谐波信号会产生频谱泄露与栅栏效应的这一问题,采用将信号先加布莱克曼窗后再进行插值修正的快速傅里叶变换算法。在使用该种算法时,在Matlab软件中编写加窗插值算法,在LabVIEW软件中搭建加窗插值算法平台,对其进行仿真实验,结果证明在相位测量时,加布莱克曼窗的插值算法可以提高检测的准确度。
毕业论文关键词:智能变电站;高精度相位测量技术;采样回路;布莱克曼窗;加窗插值
毕业设计说明书外文摘要
Title The Study of the Test of High Accurate Phase in Intelligent substation
Abstract Intelligent substation is a kind of substation that using the advanced,reliable,integrated and environmentally friendly intelligent equipment。Its basic requiremnets are the information digitization for the whole substation,communication platform networking and information sharing standardization。It can automatically complete the basic functions of information collecting,measuring,control,protection,measurement and testing。At the same time,it have the functions of supporting real-time automatic control,intelligent regulation,online analysis and decision and collaborative interaction and other advanced features of the substation。With the extensive practical application of Smart Substation,now accurate phase measurement has a very important significance to the Smart Substation reliable operation。However,there exists an uncertain time delay in the transmission process the sampling data。Therefore,taking reasonable accurate algorithm for phase measurement is very important。
The paper makes a contrast and analyses advantages and disadvantages of some commonly used algorithm for phase difference measurement。According to the effect of spectral leakage and picket fence when we directly using FFT to analyse harmonic signal,we make the signal windowed,then we make an interpolation。In the Matlab software,we can write the algorithm program。Also,we can introduce windowed interpolation algorithm using the Blackman window to the Labview platform。Finally,the simulation prove that the accuracy is greatly improved by using the algorithm to calculate the phase of the signal。
Keywords:Intelligent substation;high precision measurement of the phase;sampling loop;Blackman window;windows and interpolation
目 次
1 绪论 1
1。1 课题研究背景与研究意义 1
1。2。1 时域分析方法 2
1。2。2 频域分析方法 2
1。2。3 时频域分析方法 4
1。2。4 其他分析方法 4
1。3 课题的研究难点