학술논문
并网逆变器非线性特性建模及稳定性研究综述 / Overview on Nonlinear Modeling and Stability Analysis of Grid-tied Inverters
Document Type
Academic Journal
Author
Source
高电压技术 / High Voltage Engineering. 50(1):370-中插22
Subject
Language
Chinese
ISSN
1003-6520
Abstract
并网逆变器作为连接新能源分布式发电和电网之间的关键接口,发挥着将电能高效、高质量馈入电网的重要作用.随着新能源渗透率的持续提高,并网点处电网存在诸如高电网阻抗、丰富的低频谐波、电压幅值/频率波动甚至故障等复杂状况.鉴于并网逆变器本质上是一个多输入、强耦合的非线性系统,沿用传统的线性建模与分析方法已难以解释工程中的复杂谐波振荡现象,并网逆变器的稳定性分析及其稳定运行受到巨大挑战.为此,该文首先具体阐述了线性与非线性和系统受扰大小之间的关系,指出大干扰稳定性分析更依赖于非线性建模及分析方法的应用.在此基础上,对已见诸报道的并网逆变器稳定性分析方法进行了归纳和对比.然后,详细阐述了稳定性分析方法在并网逆变器特定非线性环节中的应用.最后,总结并讨论了现有研究的不足,以期进一步促进"双高"背景下并网装置非线性建模和稳定性分析的研究.
The grid-tied inverter,which serves as a key interface that connects the renewable-energy-based distributed power generation and the grid,plays a major role in feeding electrical energy into the power grid with high efficiency and quality.However,with the increasing penetration rate of renewable energies,the point of common coupling of the inverter suffers complex grid conditions such as large grid impedance,rich background harmonics,grid voltage fluctuations,fre-quency derivation or even grid faults.In view of the fact that the grid-tied inverter is essentially a nonlinear system with multiple inputs and strong coupling,it is difficult to explain the complex harmonic oscillation phenomenon using the tra-ditional linear modeling and stability analysis methods,which poses great challenges to the stability analysis and stable operation of the grid-tied inverter.Therefore,this paper first clarifies the relationship between nonlinearity and large-disturbance stability,indicating that the large-signal stability analysis depends more on the application of nonlinear modeling and analysis methods.On this basis,several reported nonlinear stability analysis methods in grid-tied inverters are summarized and compared.Furthermore,the application of stability analysis methods with respect to specific nonlinear factors in grid-tied inverters is elaborated.Finally,the limitations of the existing studies are discussed in order to further pro-mote the research on nonlinear modeling and stability analysis of grid-tied inverters in"double high"power systems.
The grid-tied inverter,which serves as a key interface that connects the renewable-energy-based distributed power generation and the grid,plays a major role in feeding electrical energy into the power grid with high efficiency and quality.However,with the increasing penetration rate of renewable energies,the point of common coupling of the inverter suffers complex grid conditions such as large grid impedance,rich background harmonics,grid voltage fluctuations,fre-quency derivation or even grid faults.In view of the fact that the grid-tied inverter is essentially a nonlinear system with multiple inputs and strong coupling,it is difficult to explain the complex harmonic oscillation phenomenon using the tra-ditional linear modeling and stability analysis methods,which poses great challenges to the stability analysis and stable operation of the grid-tied inverter.Therefore,this paper first clarifies the relationship between nonlinearity and large-disturbance stability,indicating that the large-signal stability analysis depends more on the application of nonlinear modeling and analysis methods.On this basis,several reported nonlinear stability analysis methods in grid-tied inverters are summarized and compared.Furthermore,the application of stability analysis methods with respect to specific nonlinear factors in grid-tied inverters is elaborated.Finally,the limitations of the existing studies are discussed in order to further pro-mote the research on nonlinear modeling and stability analysis of grid-tied inverters in"double high"power systems.