单相光伏并网发电系统孤岛检测方法的研究

发布时间：2018-05-12 19:46

本文选题：单相光伏并网发电系统 + 孤岛检测　；参考：《华东理工大学》2014年硕士论文

【摘要】：目前,全世界都面临能源枯竭和自然环境污染严重等问题。光伏发电在资源稀有的环境下已然成为全球各国重点发展的战略产业,光伏并网发电系统中的孤岛检测部分也是整个光伏发电系统中的关键部分,关系到光伏发电系统的可靠性和供电质量,因此对其研究具有重要的意义。本文首先介绍光伏并网发电系统的整体结构,其中包含光伏并网逆变的拓扑结构、光伏逆变器的类型、及滤波环节的选择等,之后给出了本文所采用的单相光伏并网发电系统的系统框图和等效模型。其次,分别介绍了孤岛检测的基本原理、孤岛检测的国内外标准以及目前孤岛检测的常用方法。接着提出一种新颖的偶次谐波注入主动式孤岛检测方法,详细介绍了其检测原理、偶次谐波注入取值范围分析和滤波方法、并在Matlab/Simulink中搭建了单相光伏并网发电系统的孤岛检测仿真模型,针对不同负载条件下的孤岛现象验证此孤岛检测方法的有效性。经过仿真表明,此方法检测速度快,几乎没有检测盲区,鲁棒性强,对大电网电能质量影响小,同时能对多台逆变器的并联运行进行孤岛检测等优点。此外,还提出了一种改进的主动频移孤岛检测方法,并对其做具体的介绍和分析。这种注入的扰动能使光伏并网逆变输出电流波形有较低的总谐波失真、相比传统的主动移频式(AFD)孤岛检测方法有更小的非检测区,同时通过实际仿真验证了改进方法光伏并网逆变输出电流波形效果的有效性。最后针对全文所做的工作做了概括总结,并提出了今后新的研究方向。
[Abstract]:At present, the world is faced with energy depletion and serious pollution of the natural environment and other problems. Photovoltaic power generation in the environment of scarce resources has become the key development of strategic industries in the world, photovoltaic grid-connected power generation system detection part is also the key part of the whole photovoltaic power system. The research of photovoltaic system is of great significance because of its reliability and power supply quality. This paper first introduces the whole structure of grid-connected photovoltaic power generation system, including the topology of grid-connected photovoltaic inverter, the type of photovoltaic inverter, and the selection of filtering links, etc. Then the system block diagram and equivalent model of single-phase photovoltaic grid-connected generation system are given. Secondly, the basic principle of islanding detection, the domestic and foreign standards of islanding detection and the common methods of islanding detection are introduced respectively. Then a novel active islanding detection method for even harmonic injection is proposed. The detection principle, range analysis and filtering method of even harmonic injection are introduced in detail. The islanding detection simulation model of single-phase photovoltaic grid-connected generation system is built in Matlab/Simulink, and the effectiveness of this detection method is verified by the islanding phenomenon under different load conditions. Simulation results show that this method has the advantages of high detection speed, almost no blind area detection, strong robustness, little influence on the power quality of large power grid, and the ability to detect the parallel operation of multiple inverters in isolated islands. In addition, an improved active frequency shift islanding detection method is presented and analyzed in detail. The injected disturbance can reduce the total harmonic distortion of the output current waveform of the grid-connected photovoltaic inverter, and it has a smaller non-detection area than the traditional active frequency shift AFD-island detection method. At the same time, the effectiveness of the improved method is verified by simulation. Finally, the work done in this paper is summarized, and a new research direction in the future is put forward.
【学位授予单位】：华东理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM615

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