摘要
提出了一种应用于孤岛微网的容错逆变器及其控制方法,并对带容错逆变器的孤岛微网系统的稳定性进行小信号建模分析。当容错逆变器某一相桥臂中的功率开关器件故障时,用直流侧电源来替代故障桥臂,使系统在故障发生后依然能够稳定运行。在逆变器的电压-电流控制环中加入虚拟阻抗,以抵消两个微源之间的环流。建立了带容错逆变器孤岛微网系统的小信号状态空间模型,利用特征值分析法对系统状态矩阵的特征根进行分析,研究了逆变器的容错拓扑结构、滤波电容以及虚拟阻抗对系统稳定性的影响。在仿真平台上搭建了带容错逆变器的孤岛微网的仿真模型,仿真结果验证了所提容错逆变器拓扑结构及其控制策略的正确性与有效性,系统在故障状态下仍能保持稳定。
A fault-tolerant inverter applied to islanded microgrid and its control method is proposed in this paper,its small-signal model is built to analyze the system stability.When the power switch device in the bridge arm of the fault-tolerant is faulty,the DC side power will replace the faulty bridge arm,so the system can operate stably after fault.Virtual impedance is added into the voltage-current control loop of inverter to offset the circulating current between two microsources.The small-signal state-space model of islanded microgrid with the fault-tolerant inverter is built,the eigenvalue analysis method can be used to analyze the eigenvalues of system state matrix,the impact of topology of the fault-tolerant inverter,the filter capacitance and the virtual impedance on system stability is studied.The simulation model of islanded microgrid with fault-tolerant inverter is built,the simulation model verifies the validity and correctness of the topology of the fault-tolerant inverter and its control method,and the system can still remain stable in fault state.
作者
黎燕
史向月
向鹏
LI Yan;SHI Xiangyue;XIANG Peng(School of Information Science and Engineering,Central South University,Changsha 410083,China)
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2019年第23期82-91,共10页
Power System Protection and Control
基金
国家自然科学基金项目资助(51507192)~~
关键词
孤岛微网
容错逆变器
环流
虚拟阻抗
小信号稳定性
islanded microgrid
fault-tolerant inverter
circulating current
virtual impedance
small-signal stability