【摘要】 风力发电作为一种清洁可再生的发电方式,在全球范围内正以惊人的速度发展。变速恒频双馈式风力发电系统要求双馈电机控制系统具有响应速度快、鲁棒性强的特点。双馈式异步电机(DFIG)在参数变化内部扰动和风机负载转矩振荡外部扰动共同影响下,会导致现有PI控制转子电流响应动态性能变差,电机工作效率和稳定性降低。滑模变结构控制(SMC)是一种基于状态空间的非线性控制方法,进行设计时与对象参数及扰动无关,这就使得SMC控制与PI控制策略相比具有快速响应、对参数变化及扰动不敏感的优点。针对上述问题,本研究在双馈电机控制系统中引入滑模变结构控制,设计一种基于指数趋近律的积分型滑模变结构控制器,并利用边界层设计以减小滑模控制的振颤。仿真表明,该控制策略可提高DFIG的动态性能,增强其抗干扰性,有效降低SMC的振颤,并具有设计过程简单、易于实现等优点。更多还原

【Abstract】 Wind power is a clean and renewable energy, and its exploitation is developing rapidly across the world. The Variable Speed Constant Frequency (VSCF) wind power generation system requires the Double Feed Induction Generator (DFIG) to have high response speed as well as good robustness. The DFIG will be affected both by internal disturbance of parametric variations and external disturbance of the load torque oscillation. The dynamics of the current response of the present PI controlled rotor may be in bad conditions. In addition, the above disturbances reduce efficiency and stability of the wind turbine. Slide Mode Control (SMC) is a kind of nonlinear control methods based on state space and is independent of object parameters and disturbances. Compared with PI control, SMC has a faster response, and is insensitive to the parameter variations and disturbances. This paper proposes a sliding-mode variable structure controllerI, as an integral action under exponential approximation law. The controller uses the boundary-layer design to reduce the vibration of the sliding-mode control. The simulation indicates that the dynamic performance and the anti-interference ability of DFIG are improved. The vibration is effectively reduced by adopting this control strategy with a simple design process and easy implementation.更多还原