中国电机工程学报2024，Vol.44Issue(15)：6136-6145,中插25,11.DOI:10.13334/j.0258-8013.pcsee.231173
开环同步型单相并网逆变器小干扰建模与弱电网下稳定性分析
Small-disturbance Modeling and Stability Analysis of Single-phase Grid-tied Inverter With Open-loop Synchronization Under Weak Grid
摘要
Abstract
In single-phase grid-tied inverters(GTI),the closed-loop synchronization based on phase-locked loop(PLL)is widely used.However,the negative-resistance characteristic introduced by PLL at low-frequency band is not conducive to the GTI stability.When the grid impedance is large,the GTI is prone to serious instability.Hence,extensive studies on the optimization or substitution of PLL are ongiong at home and abroad,in which.open-loop synchronization(OLS)itself is completely stable due to its non-feedback structure,thus receiving much attention in recent years.However,OLS owns obviously nonlinear characteristics,and it is difficult for it to obtain an accurate linearized small-signal model.The stability of GTI with OLS under very weak grid is still unclear.Therefore,this study focuses on the small-signal modeling and stability of GTI with OLS.Inspired by harmonic linearization theory,the linearization modeling method of OLS is proposed,and the output impedance model of GTI with OLS is established.On this basis,the robustness of OLS-GTI is discussed.It is found that the GTI with OLS exhibits excellent stability even under conditions of large grid impedance.The simulation and experimental results verify the accuracy of the above model and the adaptability of OLS under very weak grid.关键词
并网逆变器/弱电网/稳定性/开环同步方法/阻抗模型Key words
grid-tied inverter(GTI)/weak grid/stability/open-loop synchronization(OLS)/impedance modeling分类
动力与电气工程引用本文复制引用
许津铭,乔瑜,罗运虎,程成,谢少军..开环同步型单相并网逆变器小干扰建模与弱电网下稳定性分析[J].中国电机工程学报,2024,44(15):6136-6145,中插25,11.基金项目
国家自然科学基金项目(52277184). Project Supported by National Natural Science Foundation of China(52277184). （52277184）
