针对风力发电机常见的速度传感器故障,建立了传动系统的降阶模型,提出了改进滑模观测器的故障检测方法。采用饱和函数削弱抖振对滑模动态的影响,并将发电机转速测量差值引入滑模输入信号的设计中,使滑模增益自动调节,同时利用线性矩阵不等式可行性问题设计反馈矩阵。通过对比观测器输出值计算残差估计值,结合极大似然比确定的阈值,实现系统故障的有效检测。仿真结果证明,所提出的方法能有效地检测出风力发电机速度传感器故障。
Aiming at the common speed sensor faults of wind turbine, this paper establishes the reduced order model of the drive system, and puts forward the improved sliding mode observer (SMO) fault detection method. Adopting the saturation function to weaken the dynamic influence of chattering of sliding mode and introducing the wind rotor speed measurements difference to join SMO design. It makes the sliding mode automatic gain adjustment based on linear ma- trix inequality (LMI) feasibility problem to design feedback matrix. By comparing the output value of the observer and the estimated value, the threshold value of the maximum likelihood ratio is determined to achieve the effective detection of system failure. The simulation results show that the proposed method can effectively detect the fault of the wind tur- bine speed sensor.