风力发电系统执行器故障诊断与MPPT滑模容错控制

ACTUATOR FAULT DETECTION AND MPPT FAULT TOLERANT CONTROL FOR WIND POWER GENERATION SYSTEM BASED ON SLIDING MODE TECHNIQUE

为提高风力发电系统最大功率跟踪(MPPT)运行的工作性能与可靠度,针对系统潜在的执行器部分失效故障、未知扰动偏差故障等不确定问题,提出一种MPPT滑模主动容错控制方法。通过滑模观测器(SMO)重构实际系统的执行器故障,并将故障观测估计项引入MPPT容错控制律。为削弱控制器输出幅值的抖振,平滑输出转矩,提高跟踪精度,采用高阶滑模控制(SMC)设计MPPT容错控制器,形成风力发电系统在线故障诊断和容错控制的集成。采用Lyapunov方法证明闭环控制系统的全局稳定性。通过与常规线性PID以及1阶和2阶SMC控制进行MPPT跟踪控制性能对比仿真实验,验证该控制器实现最大功率跟踪控制的良好效果和强的执行器故障容错能力。

In order to enhance the MPPT working performance and operating reliability of wind power generation system,an active fault tolerant MPPT control method based on sliding mode control technique is proposed,which takes into account the influence of uncertainties coming from potential actuator failures and unknown disturbances on the system.It reconstructs actuator faults of the actual system through a sliding mode observer(SMO)and introduces the fault estimation terms into the MPPT fault tolerant control law.In order to weaken the chattering of the controller output amplitude,smooth the output torque and improve the tracking accuracy,a second-order sliding mode MPPT fault tolerant controll lawis designed using high-order sliding mode control(SMC)technology.In this way,the integration of on-line fault detection and fault tolerant control of the wind power generation system is formed.The Lyapunov method is used to prove the global stability of the closed-loop control system.Compared with the conventional linear PID controller as well as the first-order and second-order SMC,MPPT control performance simulation experiments verify that the proposed controller achieves good results of maximum power point tracking and strong fault tolerance capability.