摘要
针对虚拟同步发电机(VSG)在电网故障期间存在的功角失稳以及电流越限问题,提出一种基于功角与电流灵活调节的VSG低电压穿越控制策略。首先,通过分析电网电压跌落下的VSG故障特征,明确低电压穿越的控制目标;其次,根据逆变器无功支撑需求,定量设计VSG无功指令,使其为电网提供无功电流支撑;再次,根据VSG功角曲线以及等面积定则,调节VSG有功指令以增强功角稳定性,同时实现功角定量控制;接着,采用动态虚拟阻抗抑制电网故障瞬间的VSG电流冲击;最后,通过MATLAB/Simulink仿真验证了所提方案的有效性。
This paper proposes a low voltage ride through control strategy for virtual synchronous generators(VSG)to address the issues of power angle instability and current exceeding limits during power grid faults,based on flexible adjustment of power angle and current.Firstly,by analyzing the VSG fault characteristics under voltage drop in the power grid,the control objective of low voltage ride through is clarified.Secondly,based on the reactive power support requirements of the inverter,the VSG reactive power command is quantitatively designed to provide reactive current support for the power grid.Next,based on the VSG power angle curve and the equal area rule,adjust the VSG active command to enhance power angle stability and achieve quantitative control of power angle.At the same time,dynamic virtual impedance is used to suppress the VSG current surge at the moment of power grid fault.Finally,the effectiveness of the proposed scheme were verified through MATLAB/Simulink simulation.
作者
王玉强
WANG Yuqiang(Shandong Energy Group Luxi Mining Corporation,Heze 274700,China)
出处
《电气应用》
2024年第9期106-112,共7页
Electrotechnical Application
