Design On Online Monitoring And Yaw Control System Of Wind Turbine Based On PLC

Wind energy,an important part of renewable energy resource,can solve the lack of non-renewable energy resource and environment problem effectively.The development of wind power technology promotes the growth of wind turbine installed capacity.However,it also cause wind turbine faults and accidents increase.Research on online monitoring and yaw control system,which ensure the safety and reliability of wind turbine operation,has realistic significance.A large number of non-stationary signals will be generated during the operational process of rotating machinery.Based on reliable and effective methods of online monitoring and fault diagnosis,some commonly used methods in time domain methods,frequency domain methods and time-frequency analysis methods have been selected.In order to get the maximum utilization rate of wind energy,a common control algorithm for closed loop has been selected.Combining with PLC and Visual Studio,wind turbine online monitoring and yaw control system have been developed.The main research contents of this dissertation are as follows:1.Basic structure of wind turbine is introduced.In the view of high fault rates parts,the failure mechanism and vibration signal feature of rotor,gear and bearing are studied.Moreover,some usual time domain methods,frequency domain methods and time-frequency analysis methods are selected.They provide theoretical basis to system development.2.In view of operation principle and control characteristics,a closed-loop yaw control system whose feedback quantity and output are generator output power and yaw angle is designed.Moreover,this method is verified by simulated analysis.3.In view of wind turbine gearbox,the sensor and capture card are selected.Based on PLC hardware platform,data acquisition module,data processing module,alarm module and data storage module are developed.Communication module and upper computer system are developed by C#,network techniques and database technology.The whole system comprise online monitoring which is the main body of system and yaw control which is auxiliary part of system.4.Wind turbine online monitoring and yaw control system is used to analyse a certain gearbox.According to alarm state and fault diagnosis analysis,the whole system is proved to be effective and accurate by comparing the diagnosis with actual faults.