不平衡负载下独立运行双馈发电系统的矢量控制

Vector Control of Stand-alone Doubly-fed Wind Power Generation System Under Unbalanced Loads

针对连接不平衡负载的双馈电机独立运行控制,提出一种基于改进超螺旋观测器和非奇异终端滑模的矢量控制方法。通过改进超螺旋观测器观测转子电流的基频和二倍频分量,减少对双馈电机参数的依赖,提高系统的抗干扰能力。设计基于改进超螺旋观测器的非奇异终端滑模转子电流控制器,消除由不平衡负载引起的滑模面波动,增强对二倍频交流给定信号的跟踪性能,进而改善对负序定子电压的抑制能力。仿真与实验结果表明,所提方法能够在不平衡负载条件下有效抑制定子电压中的负序分量,具有优异的动静态性能。

A vector control method based on the modified super-twisting observer and non-singular terminal sliding mode was proposed for stand-alone doubly-fed wind power generation systems under unbalanced loads.The fundamental frequency and double frequency components of the rotor current were observed by the modified supertwisting observer,which reduces the dependence on the parameters of the doubly-fed wind power generation and improves the anti-interference ability of the system.A non-singular terminal sliding mode rotor current controller based on a modified super-twisting observer was designed,which eliminates the sliding mode surface fluctuation caused by unbalanced loads,enhances the tracking performance of the AC given,and improves the suppression ability of negative sequence stator voltage.Simulation and experimental results show that the proposed method can effectively suppress the negative sequence component of stator voltage under unbalanced load conditions,and has the excellent dynamic and static performance.