三相四线制供电系统电流谐波分析.doc

目录 摘 要 2 第1章 绪 论 4 1.1 引言 4 1.2 课题来源及研究的目的和意义 5 1.3 国内外在该方向的研究现状及分析 5 第2章 谐波理论基础 6 2.1 谐波的基本概念 6 2.2 谐波的产生 9 2.3 谐波的危害 10 2.4 谐波限制标准 11 2.5 本章小结 12 第3章 谐波检测方法分析 12 3.1 频域理论 12 3.2 时域理论 13 3.2.1 快速傅立叶变换 13 3.2.2 基于瞬时无功功率检测方法 14 3.2.2.1 法 21 3.2.2.2 法 22 3.2.2.3 Park变换的法 24 3.2.3 基于神经网络的谐波检测方法 25 3.3 本章小结 25 第4章 仿真分析 27 4.1 仿真软件简介 27 4.2 三相整流电路仿真 28 4.4 基于瞬时无功功率的单相谐波检测 32 结 论 35 致 谢 36 参考文献 37 摘 要 在电力系统中许多电气元件都产生不同程度的谐波，各种整流设备，交直流换流设备尤为严重。由此带来的危害和其谐波抑制是广泛关注的课题。 本文以三相四线制低压供电系统为例，首先介绍了谐波的基本概念、谐波的产生及其危害、电网对谐波电压和谐波电流的限值，阐述了谐波问题研究的必要性，国内外研究的状况及本文研究的内容，然后分析了谐波理论基础，详细的介绍了三相谐波检测方法、及基于瞬时无功功率检测方法。最后对设计的谐波检测方法，利MATLAB/simulink进行仿真， 在仿真中，利用MATLAB/Simulink建立了整流电路总体仿真模型。编写了数据傅立叶分析软件。通过仿真波形、分析数据表明了此仿真模型的真实性和方案的可行性。 关键词 谐波电流检测; 瞬时无功功率理论; Matlab/Simulink; 三相整流电路桥 Abstract A lot of electric components produce various degrees of harmonies in the power system, it is particularly serious to do it such as various kinds of rectification equipment and inverters and converters. Therefore the danger brought and its wave in harmony are suppressed it is subjects that a lot of people pay close attention to extensively. The paper introduces the concept of harmonics, its harm to power grid and limitation of harmonics voltage and current harmonics，and it also demonstrates the necessity of eliminate harmonics, and briefly introduces several methods to eliminate harmonics and research of both here and abroad. The paper analyzes the principles of the harmonic. Then the paper detailed introduces the theory of the way of harmonic currents of a single-phase and the way of harmonic currents of a there-phase and instantaneous reactive power,. In the end the paper simulates harmonics detection methods by MATLAB/simulink. In the simulink, utilize Matlab/Simulink to set up commutate circuit mode. Write its data FFT analyses software. By showing the wave form and analyzing data, indicate the authenticity of this simulink model and feasibility of the scheme. Key word: harmoni