双级式光伏发电系统前级控制器参数设计与后级有源阻尼控制策略研究

发布时间：2018-01-02 04:20

本文关键词：双级式光伏发电系统前级控制器参数设计与后级有源阻尼控制策略研究　出处：《内蒙古工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：能源和环境问题推动了新能源发电的快速发展,也造就了光伏发电迅猛发展的态势。本文以双级式光伏并网发电系统为研究对象,在进行状态空间平均建模的基础上给出了前级控制器参数的系统化设计方法,采用电容并联虚拟电阻有源阻尼法,给出了含有LCL滤波器的并网变换器有源阻尼功率解耦控制策略,通过仿真研究验证了控制器参数设计方法和解耦控制策略的正确性。本文首先介绍了课题研究的背景、目的和意义,概述了国内外光伏发电的发展情况;综述了双级式光伏并网变换器的拓扑结构与控制技术。其次介绍了双级式光伏并网发电系统的总体结构及工作原理,进行了前级变换器系统特性分析与参数设计。针对前级变换器系统功率电压双闭环MPPT结构采用状态空间平均建模法建立了系统的非线性模型,进而采用平衡点附近线性化方法得到其线性模型。在频率特性和根轨迹分析的基础上,给出了前级控制器参数的系统化设计方法,避免了试凑法的盲目性。再次介绍了后级含有LCL滤波器的并网变换器系统的工作原理和调制方式,并进行了LCL滤波器的参数设计。采用电容并联虚拟电阻有源阻尼法来抑制LCL滤波器的谐振,在此基础上给出了含有LCL滤波器的并网变换器有源阻尼功率解耦控制策略。最后建立了12k W双级式光伏并网发电系统的仿真模型,仿真结果表明,在标准光强下和模拟自然条件光强变化时,本文所论控制器和控制策略能快速实现最大功率跟踪控制和单位功率因数并网控制,并有效抑制滤波器的谐振,取得了良好的控制性能。
[Abstract]:Energy and environment problems promote the rapid development of new energy generation, but also bring up the rapid development of photovoltaic power. This paper takes the two-stage photovoltaic grid-connected power generation system as the research object. Based on the state-space average modeling, a systematic design method for the parameters of the controller is presented, and the capacitive shunt virtual resistance active damping method is adopted. The decoupling control strategy of active damping power of grid-connected converter with LCL filter is presented. The design method of controller parameters and decoupling control strategy are verified by simulation. Firstly, the background, purpose and significance of the research are introduced, and the development of photovoltaic power generation at home and abroad is summarized. The topology structure and control technology of two-stage photovoltaic grid-connected converter are summarized. Secondly, the overall structure and working principle of two-stage photovoltaic grid-connected power generation system are introduced. The system characteristics and parameters of the former converter are analyzed and the nonlinear model of the system is established by using the state-space average modeling method for the dual-closed-loop MPPT structure of the power and voltage of the former converter system. Then the linear model is obtained by linearization near the equilibrium point. Based on the analysis of the frequency characteristics and the root locus, the systematic design method of the parameters of the former controller is presented. The blindness of trial and error method is avoided. The working principle and modulation mode of grid-connected converter system with LCL filter are introduced again. The parameter design of the LCL filter is carried out. The capacitive shunt virtual resistance active damping method is used to suppress the resonance of the LCL filter. The decoupling control strategy of active damping power of grid-connected converter with LCL filter is presented. Finally, the simulation model of 12kW two-stage photovoltaic grid-connected power generation system is established, and the simulation results show that. Under the standard light intensity and the simulation of natural light intensity change, the controller and control strategy discussed in this paper can quickly realize the maximum power tracking control and the unit power factor grid-connected control, and effectively suppress the resonance of the filter. Good control performance has been achieved.
【学位授予单位】：内蒙古工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TM615

【相似文献】