Fault Diagnosis And Fault Tolerant Control Of Wind Turbine Based On Photoelectric Detection

Wind power has become one of the most promising renewable energy sources.Because of the bad operating environment and changeable operating conditions of wind turbine,it is very easy to fail.Once the failure is not dealt with in time,it will cause irreparable economic loss.Therefore,it is necessary to study the fault diagnosis and fault-tolerant control of wind power generation system.This paper has carried out the following research:Firstly,the energy conversion efficiency is analyzed and calculated from the aerodynamics effect,and the model of each link of wind power generation system is established.Secondly,the principle of maximum power tracking control of wind turbine running in low wind speed area is studied.Aiming at the problem of non modeling dynamic and external noise interference in the actual wind power generation system,the maximum power tracking strategy of adaptive non singular fast terminal sliding mode control is designed.The results show that the proposed method can effectively improve the wind energy utilization coefficient and the output power of the fan.In order to deal with the noise of tower vibration acceleration signal caused by tower vibration and wind shear effect,a method of noise reduction based on empirical wavelet transform is proposed to deal with the signal measured by FBG vibration acceleration sensor.Firstly,the principle and method of FBG acceleration sensor are introduced.Secondly,the signal decomposition method of empirical wavelet transform is proposed for the problem of mode aliasing of empirical mode decomposition.Finally,the noise reduction of the decomposed signal is processed by using the improved threshold.The simulation results show that the proposed method has higher signal-to-noise ratio,can effectively reduce the impact of noise,and improve the measurement accuracy of the lateral vibration acceleration of the wind turbine tower..Considering the speed sensor fault of photoelectric encoder in wind power system,a fault reconstruction method based on observer is proposed to solve the problem of poor universality of hardware diagnosis method.In view of the high complexity of traditional methods and poor real-time performance of fault estimation,a sliding mode observer is designed to estimate the state and sensor faults of wind power generation system.The faulttolerant controller is designed by the fault reconstruction information,which ensures the stable operation of the system.In view of the problem of the poor accuracy of the state and the actuator fault estimation of wind power system,an adaptive generalized sliding mode observer is proposed.By constructing an augmented system,the actuator fault becomes a part of the system state.The generalized sliding mode observer is designed to estimate the state of the augmented system to obtain the required fault information.In view of the problem that the upper bound of fault is unknown in the actual wind power system,an adaptive algorithm is designed to estimate the upper bound of fault information.The active fault-tolerant controller is designed by combining the adaptive non singular fast terminal sliding mode algorithm to ensure the reliable output of wind power system under actuator failure.The simulation results show that the fault problem of photoelectric sensor and actuator can be solved by the proposed fault reconstruction and fault-tolerant control strategy.