文档介绍：重庆大学工程硕士学位论文中文摘要 I 摘要电力系统中,电能是以额定的频率和电压向用户供电。对电能的质量也是用频率和电压来表征。但是仅用这两个指标来表征电能的质量很不完善。波形畸变和三相交流电力系统中三相电压或电流的不平衡也是影响电能质量的重要因素。近年来,由于大功率电力电子技术的发展以及它们在各种领域的广泛应用,使非线性负荷大量增加。它们对电力设备以及用户和通讯线路带来有害的影响。波形畸变已日益成为人们关注的问题。电网中谐波问题需进行理论研究,也必须进行实际测量和治理的研究。但由于电网中谐波问题复杂,往往要从实际测量的结果进行深入研究。因此,要求有可靠的测试手段与装置,进行长期在线监测。论文分析了目前国内外生产的谐波分析仪采用快速傅里叶变换(FFT)算法,用于电力系统谐波测量产生误差的原因; 本文对该算法的误差进行了详细的分析和仿真,分析了该算法受非周期衰减分量的影响,对波动性谐波负荷的测量将产生难以补偿的误差,影响其测量结果的可信度;提出了一种用于谐波测量改进的Fourier算法;该算法利用周期分量的对称性,滤去衰减的非周期分量,进而测量出谐波负荷的非周期分量和周期分量,使测量结果更加真实可信;按国标GB/T 14549-93标准提出一种以DSP、工业控制微机工作站为核心的谐波自动分析计算方法,其精度好,适宜于长期在线监测;利用DSP设计了谐波测试器的硬件系统和软件系统,在上位计算机开发了变电站谐波监测和分析软件,为进一步提高电力系统质量,分析谐波产生的原因,和采取治理措施奠定了理论基础。关键词:配电网,谐波,傅里叶变换重庆大学工程硕士学位论文英文摘要 II ABSTRACT Power is supplied to consumers with rated frequency and voltage in power systems and the quality of electrical energy is evaluated by these two factors. But it’s hard to evaluate the quality only with these two factors and the problems of waveform aberration and imbalance of voltage and current in 3-phase AC power systems can also affect the quality. Nowadays, with the development of high-power electronics and its wide applications, power equipments, consumers works have been badly affected by large numbers of non-liner loads in power systems. Therefore, waveformaberration has been a considerable problemfor the people. It’s necessary to take practical measurement and treatment researches to solve the problem of harmonics in works as well as having theoretic studies. For plexity of the harmonics problem in power systems, deeply analysis with the result of practical measurementis necessary. Thus, reliable measure methods and equipments are required to long-time on-line monitor. Nowadays, FFT algorithm is usually used in the harmonics analysis equipments. The reason for the error produced by harmonics measuring has been analyzedand the error of the algorithm has been analyzed and simulated in detail in this paper. The measure results are unbelievable because the non-periodic ponent