基于单相准Z源逆变器的光伏并网研究

发布时间：2018-03-11 02:14

本文选题：准Z源逆变器　切入点：光伏并网　出处：《华北电力大学》2017年硕士论文　论文类型：学位论文

【摘要】：能源与社会的发展息息相关,传统能源的短缺以及其对环境的污染,促使了人们对可再生清洁能源的重视。各种新能源发电系统,如燃料电池、风力发电、光伏发电、潮汐发电等得到了大力发展。而光伏发电作为其中最清洁、最安全、潜力最大的发电方式,成为业界的研究热点。光伏电池的输出为直流电,需要经过逆变电路,将直流电转换为交流电,经滤波后并入电网。由于传统电压型(电流型)逆变器只能降(升)压的局限性,本文对一种新型的逆变拓扑——单相准Z源逆变器进行了研究。在文中首先对电流连续型的准Z源逆变器的稳态工作原理进行了理论分析,简述了其升压控制方法,以及在简单升压控制下的阻抗网络参数设置。为了分析系统的动态性能,根据状态空间平均法建立了小信号模型,得到输入变量与状态变量之间的传递函数与其零根轨迹图,分析了参数对系统动态响应的影响。进而对单相准Z源逆变器的光伏并网进行了研究,采用电容电压恒压控制方法,该控制方法使电容电压保持恒定,从而使输入功率和输出功率解耦。在并网电流控制中采用能够实现抗电网电压干扰和无静差的准PR控制器,并对其参数进行了整定。而后通过Matlab/Simulink进行了仿真,验证了电容电压恒压控制方法的有效性,并采用变步长的扰动观察法,实现了系统输出的最大功率点追踪。
[Abstract]:Energy is closely related to the development of society. The shortage of traditional energy and its pollution to the environment make people pay more attention to renewable and clean energy. All kinds of new energy generation systems, such as fuel cells, wind power, photovoltaic power generation, Tidal power generation has been greatly developed. Photovoltaic power generation as one of the cleanest, safest and most potential power generation methods has become a research hotspot in the industry. The output of photovoltaic cells is direct current, which requires inverter circuit. Conversion of DC to AC is filtered and incorporated into the grid. Because of the limitation that conventional voltage-source (current-source) inverters can only drop (raise) voltage, In this paper, a new inverter topology, single-phase quasi-Z-source inverter, is studied. Firstly, the steady state operation principle of the current-continuous quasi-Z-source inverter is theoretically analyzed, and its boost control method is briefly described. In order to analyze the dynamic performance of the system, a small signal model is established according to the state space averaging method, and the transfer function between the input variable and the state variable and its zero root locus are obtained. The influence of parameters on the dynamic response of the system is analyzed. Furthermore, the grid-connected photovoltaic system of single-phase quasi-Z-source inverter is studied. The capacitor voltage constant voltage control method is used to keep the capacitance voltage constant. Thus, the input power and output power are decoupled. In grid-connected current control, a quasi-PR controller, which can resist voltage interference and no static error, is adopted, and its parameters are adjusted. Then the simulation is carried out by Matlab/Simulink. The effectiveness of the capacitor voltage constant voltage control method is verified, and the maximum power point tracking of the system output is realized by using the variable step size perturbation observation method.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM464

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