……………………. ………………. ………………… 装 订 线 ……………….……. …………. …………. ……… 山东农业大学
毕 业 论 文
基于瞬时无功功率理论的三相谐波电流分析与检测
院 部 机械与电子工程学院 专业班级 电气工程及其自动化3班 届 次 20**届________ 学生姓名 _________ 学 号 _______ 指导教师 _________
二О**年六月一日
目 录
摘要 ..................................................................... Ⅰ Abstract ................................................................... Ⅱ 1 绪论 ...................................................................... 1
1.1 课题背景及意义 ...................................................... 1 1.2 国内外研究现状 ...................................................... 1 1.3 论文主要内容 ........................................................ 2 2 谐波与谐波分析 ............................................................ 3
2.1 谐波的产生及分布 .................................................... 3 2.2 谐波的危害 .......................................................... 4 2.3 电网谐波的相关标准 .................................................. 6 2.4 谐波的抑制 .......................................................... 8 3 瞬时无功功率理论及其应用 ................................................ 12
3.1 瞬时无功功率理论定义 ............................................... 12 3.2 αβ坐标系中的瞬时无功功率理论 ..................................... 12 3.3 p-q检测法 .......................................................... 13 3.4 ip—iq检测法 ........................................................ 16 4 仿真分析 ................................................................ 17
4.1 基于瞬时无功功率理论的ip-iq检测法建模 ............................. 17 4.2 波形分析 ........................................................... 21 5 总结 .................................................................... 24 参考文献 ................................................................... 25 致 谢 ................................................................... 26
Contents
Chinese Abstract ........................................................................................................................... Ⅰ English Abstract ............................................................................................................................ Ⅱ 1 Introduction ................................................................................................................................. 1
1.1 Background and significance of the selected topic ........................................................... 1 1.2 Research of harmonic at home and abroad ....................................................................... 1 1.3 Main idea of the paper ...................................................................................................... 2 2 Harmonic and harmonic analysis ................................................................................................ 3
2.1 Production and distribution of harmonics ......................................................................... 3 2.2 Harm of harmonics ........................................................................................................... 4 2.3 The relevant standards for the harmonic of the electric network ..................................... 6 2.4 Suppression of harmonics ................................................................................................. 8 3 Instantaneous reactive power theory and its application ........................................................... 12
3.1 Definition of instantaneous reactive power theory ......................................................... 12 3.2 Instantaneous reactive power theory in αβ coordinate system ....................................... 12 3.3 Detection method of p-q ................................................................................................. 13 3.4 Detection method of ip—iq .............................................................................................. 16 4 Simulation analysis ................................................................................................................... 17
4.1 ip-iq detection models based on instantaneous reactive power theory ............................ 17 4.2 Waveform analysis .......................................................................................................... 21 5 Conclusion .................................................................................................................................. 24 References ..................................................................................................................................... 25 Acknowledgement ......................................................................................................................... 26
基于瞬时无功功率理论的三相谐波电流分析与检测
作者: 指导老师:
(山东农业大学 机械与电子工程学院 讲师)
【摘要】近年来,随电力电子技术在电力系统中的广泛应用以及非线性负荷的增加,工业得到了快速的发展,但也使公用电网的谐波污染越来越严重,导致电能质量的下降,使供电、用电的安全、经济性以及居民的生活受到严重影响。因此有必要实时准确地测量出电网中的谐波含量,从而进行谐波抑制。目前谐波检测方法的达数十种,其中由日本学者赤木泰文提出的“瞬时无功功率理论”的应用最广泛,包括p-q算法和ip-iq算法。其原理是把三相电路的ia ,ib ,ic的瞬时值转换到另一个坐标系α-β上研究,此法可以在三相电压对称且无电压畸变时准确地测量出基波电流,进而求出三相谐波电流。最后,用MATLAB 7.0中的Simulink软件搭建电路模型,进行仿真,得出波形。 关键词:谐波 谐波电流检测 瞬时无功功率理论 MATLAB
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Research on Harmonic current detection based on Instantaneous
Reactive Power Theory in Three-Phase Circuit
Author: Supervisor:
(Mechanical & Electrical Engineering College of Shandong Agricultural University, Lecturer )
Abstract Recently, with the wide application of power electric technology and the non-linear load device used in power systems, industry has been developed rapidly. But the harmonic pollution of the power system is gradually serious and decreased the power quality. The decline of power quality will affect the power supply and the security and economic of electricity. It’s also affect the lives of the population. So, it is necessary to measure the harmonic content accurately and timely. There are many methods of harmonic detection, and the most widely used is based on instantaneous reactive power theory, contains p-q and ip-iq algorithms. The principle is to convert the instantaneous value of the three-phase circuit ia ,ib ,ic to another coordinate system names α-β. This method can be used to detect the fundamental current when the voltage is symmetry and without distortion, then the three-phase harmonic current is obtained. Finally, the simulink in matlab 7.0 is used to build models and analyze the wave.
Keywords:Harmonic; the harmonic component current detection; instantaneous reactive power; MATLAB
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