摘要
由于风电场网侧换流器与柔直整流器之间存在次同步交互,直驱风电场经柔直并网系统存在发生次同步振荡(sub-synchronous oscillation,SSO)的风险。针对这一现象,考虑到系统的非线性和不确定性,提出一种基于反馈线性化滑模控制的SSO抑制策略,并将其应用在风机网侧变流器和柔直整流器上。所提出的抑制策略结合了反馈线性化控制(feedback linearization control,FLC)和滑模控制(sliding mode control,SMC)的优点。FLC主要通过坐标变换和反馈将非线性系统转化为线性系统形式,消除风机网侧换流器和柔直整流器控制环节的非线性;SMC主要通过设计滑模面和控制律,用于弥补FLC对参数摄动或外部扰动敏感的缺点。特征值分析和PSCAD/EMTDC时域仿真结果表明,相比于传统比例积分控制、次同步阻尼控制和FLC,所提出的非线性控制策略在不同运行工况下均具有良好的SSO抑制效果,且对参数摄动或外部扰动具有强鲁棒性。
Due to the sub-synchronous interaction between the grid-side converter of wind farms and the rectifier of voltage source converter-based high-voltage direct current(VSC-HVDC)transmission system,sub-synchronous oscillation(SSO)can occur in direct-drive wind farms with VSC-HVDC systems.In light of this,considering the system nonlinearity and uncertainty,an SSO mitigation strategy was proposed based on the feedback linearization sliding mode control(FLSMC),which was applied in the grid-side converter of wind farms and the rectifier of VSC-HVDC.The proposed mitigation strategy combined the advantages of feedback linearization control(FLC)and sliding mode control(SMC).FLC mainly transformed a nonlinear system into a linear system through coordinate transformation and feedback,thus eliminating the nonlinearity of the control links of grid-side converter and rectifier.Considering that the FLC is sensitive to parameter perturbation or external disturbance,the SMC was designed to solve this issue based on sliding mode surface and control law.Eigenvalue analysis and PSCAD/EMTDC time-domain simulation results show that compared with traditional proportional-integral control,sub-synchronous damping control and FLC,the proposed nonlinear control can mitigate SSO effectively under different conditions,while showing good robustness against the parameter perturbation or external disturbance.
作者
邵冰冰
赵书强
高本锋
沈俊铃
刘毅
易友川
SHAO Bingbing;ZHAO Shuqiang;GAO Benfeng;SHEN Junling;LIU Yi;YI Youchuan(Key Laboratory of Distributed Energy Storage and Microgrid of Hebei Province(North China Electric Power University),Baoding 071003,Hebei Province,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2021年第9期3090-3105,共16页
Proceedings of the CSEE
基金
河北省自然科学基金项目(E2020502066)
中央高校基本科研业务费专项资金资助项目(2020MS091)
中央高校基本科研业务费重点项目(2018ZD001)。
关键词
直驱风电场
柔性直流输电
次同步振荡
反馈线性化
滑模控制
非线性
鲁棒性
direct-drive wind farms
voltage source converter-based high-voltage direct current(VSC-HVDC)
sub-synchronous oscillation(SSO)
feedback linearization
sliding mode control
nonlinear
robustness
