基于一阶LADRC控制的直驱风机次同步振荡抑制策略

Subsynchronous Oscillation Mitigation Strategy Based on First-Order LADRC for Direct-Drive Wind Turbines

针对直驱式风电机组接入弱交流电网诱发次同步振荡(subsynchronous oscillation,SSO)问题,提出一阶线性自抗扰控制(linear active disturbance rejection control,LADRC)策略抑制该现象,从而提高系统稳定性。首先,建立直驱式风电机组的并网数学模型,分析次同步振荡频率扰动分量的传播机理;然后,进行一阶LADRC电流内环控制器设计以及参数优化整定,分析表明:控制器对于次同步频率扰动分量有较强的抑制作用。最后,基于PSCAD/EMTDC仿真软件,建立传统PI和一阶LADRC控制的直驱式风电机组电磁暂态仿真模型。结果表明:所提方法能够阻断次同步频率扰动分量传播,有效抑制SSO。

Aiming at solving the problem of subsynchronous oscillations(SSOs)induced by direct-drive wind turbines connected to the weak AC power grid,this paper proposes a first-order linear active disturbance rejection control(LADRC)strategy to suppress this phenomenon,thereby improving system stability.Firstly,the grid-connected mathematical model of direct-drive wind turbines is built,and the propagation mechanism of frequency disturbance components of SSOs is analyzed.On this basis,we design the firstorder LADRC inner-loop current controller and optimize and tune the parameters,and the analysis indicates that the controller has a strong inhibitory effect on the frequency disturbance components of SSOs.Finally,using PSCAD/EMTDC simulation software,we build an electromagnetic transient simulation model of direct-drive wind turbines controlled by traditional PI and first-order LADRC.The results demonstrate that the proposed method can block the frequency disturbance components of SSOs and effectively suppress SSOs.