摘要
依据基于电压源型换流器的高压直流输电(VSC-HVDC)对系统暂态稳定性的影响机理,提出一种提高系统暂态稳定性的VSC-HVDC有功无功联合附加控制策略。从VSC-HVDC功率特性与系统等值功角的关系出发,建立含VSC-HVDC有功无功附加量的交直流混联系统暂态稳定分析数学模型。针对数学模型的非线性,采用精确反馈线性化进行坐标变换,并采用滑模控制利用反映系统暂态特征的等值功角变化速度与加速度设计切换面,结合设计的有功无功配合方式,确定了VSC-HVDC有功无功附加量随系统暂态特征量实时调节的控制律,其参数设计与计算过程简便。仿真结果表明所提控制策略充分利用了换流站的功率调节能力,有效降低了系统等值功角首摆幅度,加快系统恢复稳定。
Based on the influence mechanism of voltage source converter based high voltage direct current(VSC-HVDC)on the transient stability of the system,a combined active and reactive additional control strategy of VSC-HVDC is proposed to improve the transient stability of the system.Based on the relationship between VSC-HVDC power characteristics and system equivalent power angle,a mathematical model for transient stability analysis of AC-DC hybrid system with the additional active and reactive power of VSC-HVDC is established.Aiming at the nonlinearity of the mathematical model,the exact feedback linearization is used for coordinate transformation,and sliding mode control is used to design a switching surface based on the equivalent power angle change velocity and acceleration reflecting the transient characteristics of the system.Combined with the designed active power and reactive power coordination mode,the control law of real-time adjustment of the additional active and reactive power of VSC-HVDC with the transient characteristics of the system is determined,and the parameter design and calculation process of the control law are simple.The simulative results show that the proposed control strategy makes full use of the power regulation ability of the converter station,effectively reduces the amplitude of first swing of the equivalent power angle,and speeds up the system to restore stability.
作者
姜惠兰
肖瑞
JIANG Huilan;XIAO Rui(Key Laboratory of Smart Grid of Ministry of Education,Tianjin University,Tianjin 300072,China)
出处
《电力自动化设备》
EI
CSCD
北大核心
2024年第8期138-144,共7页
Electric Power Automation Equipment
关键词
柔性直流输电
暂态稳定性
精确反馈线性化
滑模控制
附加控制
VSC-HVDC
transient stability
exact feedback linearization
sliding mode control
additional control
