含UDE附加阻尼支路的构网型直驱永磁同步风电机组次同步振荡抑制策略  

Sub-Synchronous Oscillation Suppression Strategy for Grid-Forming Direct-Drive Permanent Magnet Synchronous Generator with Uncertainty and Disturbance Estimator Supplementary Damping Branch

作　　者：陈建 任永峰 孟庆天 薛宇 何晋伟 Chen Jian;Ren Yongfeng;Meng Qingtian;Xue Yu;He Jinwei(College of Energy and Power Engineering Inner Mongolia University of Technology,Hohhot 010051 China;Beijing Tianrun New Energy Investment Co.Ltd,Beijing 100020 China;School of Electrical and Information Engineering Tianjin University,Tianjin 300072 China)

机构地区：[1]内蒙古工业大学能源与动力工程学院,呼和浩特010051 [2]北京天润新能投资有限公司,北京100020 [3]天津大学电气自动化与信息工程学院,天津300072

出　　处：《电工技术学报》2024年第7期1985-2000,共16页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51967016,51567020);内蒙古自治区自然科学基金(2022LHQN05001)资助项目。

摘　　要：针对构网型直驱永磁同步风电机组在弱电网下的次同步振荡问题,该文提出了基于不确定性和扰动估计器(UDE)的附加阻尼支路振荡抑制策略。首先,网侧变流器采用虚拟同步机(VSG)技术,并基于谐波线性化理论建立了网侧变流器序阻抗模型;其次,深入分析引入电压电流双闭环控制对弱电网下构网型直驱永磁同步风电机组产生次同步振荡的影响特性,提出了电流环引入UDE附加阻尼支路的振荡抑制策略,并基于UDE的附加阻尼控制采用滤波带宽思想对系统扰动进行估计,通过动态电压补偿方式实现阻尼支撑,可有效抑制次同步振荡,提升系统鲁棒性;最后,通过时域仿真验证了所提振荡抑制方法的有效性。Under the background of continuous growth of wind power installed capacity,grid-forming converters are used to solve the problem of system inertia loss caused by high proportion of power electronic equipment in wind power system.During the interaction between the grid-forming direct-drive permanent magnet synchronous generator(D-PMSG)and the weak grid,its equivalent capacitance and the weak grid inductance produce resonance.Especially in remote areas,the sub-synchronous oscillation occurs with the resonance diverging under condition of negative damping.Compared with the traditional sub-synchronous oscillation dominated by shafting dynamics,the oscillation phenomenon in the new power system often begins with small signal negative damping divergence and ends in nonlinear continuous oscillation,which shows the characteristics of wide oscillation frequency range.In order to solve the problem of sub-synchronous oscillation caused by the lack of damping,an oscillation suppression strategy of supplementary damping branch based on uncertainty and disturbance estimator(UDE)in grid-forming D-PMSG is proposed.The sequence impedance model of grid-side converter is established,and the stability of virtual synchronous generator(VSG)with or without voltage-current double closed-loop is analyzed.The sequence impedance of VSG without voltage-current double closed-loop is inductive as a whole,which is similar to the characteristics of traditional synchronous generator.Under this mode,there is no interactive resonance with the weak grid,and the system stability is good,but it cannot achieve accurate voltage regulation and current limiting.The positive sequence impedance of VSG with voltage-current double closed-loop is capacitive as a whole,and the negative damping characteristics appear locally,which has the risk of sub-synchronous oscillation.In order to improve the damping characteristics of grid-forming D-PMSG,the UDE supplementary damping branch is introduced into current loop.The mathematical model of UDE damping controller i

关 键 词：直驱永磁同步风电机组 次同步振荡 虚拟同步发电机 不确定性和扰动估计器 附加阻尼 

分 类 号：TM712[电气工程—电力系统及自动化]