【作者】 林琳；

【导师】 董秀成；

【作者基本信息】 西华大学 ， 电力电子与电力传动， 2007， 硕士

【摘要】 系统中的发电机、变压器、线路和用电设备的非线性或不对称，加之控制手段不完善以及外界干扰和各种故障是造成系统电压不平衡及电压正弦波畸变的主要原因，所以产生电能质量问题。针对传统电能质量分析仪存在的存储容量小，显示功能单调，非正弦电参量测量误差大，数据分析处理能力欠缺等问题，本文提出了基于LabWindows／CVI虚拟技术平台的电能质量分析系统的设计方案。首先介绍了电能质量分析系统的研究现状和电能质量的分析方法。然后，对电能质量的现象(包括定义、产生原因、危害)做的详细的分析；其次，介绍了电能质量的数学分析方法，主要是傅立叶变换，窗函数，频谱混叠和泄露效应的数学分析方法。再次，详细说明了本文设计的电能质量分析系统的硬件搭建和软件实现。硬件方面，本文选用了基于PXI总线的仪器系统完成硬件搭建。软件方面，以LabWindows／CVI为开发平台完成了电能质量基本指标的分析和处理，包括信号采集，信号分析和测试数据存储等功能。利用过零检测方法进行频率检测和测量；利用快速傅立叶变换求出基波和谐波幅值、相位；利用相关方法求信号的相位差及利用比较方法求电压波动。最后，对实验测试数据中的误差进行了分析并提出了改善措施，并对本系统中的不足做了描述，对电能质量分析装置的发展趋势也进行了必要的展望。更多还原

【Abstract】 Generator, transformer, circuitry, the non-linear or asymmetry of the consumers in system, as well as control means incomplete, outside interference and various failures is mainly responsible for system voltage unbalance and sine voltage distortion. So power quality problem arises. In view of the problem that the storage capacity is small, the display function is monotonous, measurement error of non-sinusoidal parameter is big and the data analyzing and processing is imperfect for traditional power quality analyzer, this paper introduce the design scheme of power quality analyzing system based on LabWindows/CVI.First, presents situation and analyzing measurement about power quality. Second, analyze the power quality indicators included define, causation and hazard. Third, present the mathematical analyses method about power quality which includes Fourier Transform, Window Function, Spectrum Aliasing and Spectrum Leakage. Fourth, detailedly depict the hardware and software design of power quality analyzing system. Adopt virtual instrument system basing on PXI to accomplish hardware setting up. In software, base on LabWindows/CVI platform to accomplish analyzing and processing of power quality indicators includes acquiring signal, analyzing signal, saving signal. Measure the frequency by Zero Cross Detection. Measure the amplitude and phase of fundamental and harmonious by Fast Fourier Transform. Obtain the phase deflection by correlation and the voltage fluctuation by comparison. Last, analyze the error of the measuring data and propose improving measure. Depict the shortage in this design, and make a prospect for the trend of power qualityanalyzing system.更多还原