Load Reduction Control Of Tower And Transmission Chain Of Large Scale Wind Turbine

With the development of large-scale wind turbine,the dynamic load has more and more influence on the key components.The vibration of the wind turbine caused by the dynamic load will result in the increase of the load of each component.Once the dynamic load of a component exceeds the load limit,the wind turbine will have the safety problem.Therefore,the study of wind turbine tower and transmission chain load reduction is of great significance to the safe and stable operation of the wind turbine.The 2MW doubly fed asynchronous wind turbine is used as the calculation model.In the control stage of the variable pitch control over the rated wind speed and the PI control stage of the electromagnetic torque at the rated speed,damping increase and load reduction is carried out,the load of the tower and drive chain of the wind turbine is optimized.First,the model of wind turbines above the rated wind speed in Bladed is linearized and the state space matrix is derived.The Simulink pitch control state space model is established.The transfer function of the added drag is applied to the pitch control model by the tower block design.Better control parameters are obtained by comparing the vibration and load response of the output.Secondly,the state space matrix of the rated speed is derived in Bladed.The PI control state space model of simulink electromagnetic torque is established at the rated speed stage.The transfer function of the added drag is applied to the electromagnetic torque PI control model through the design of the drive chain addition resistance,the better control parameters are obtained by comparison.Finally,the added resistance transfer function of the tower and transmission chain is applied to the control system of the wind turbine model.The simulation calculation of the steady state wind speed and the turbulence wind speed is carried out,and the conclusion is drawn after comparison.Through the simulation of simulink,damping control of tower and drive chain have a good effect on the vibration reduction and reducing load of the wind turbine.Through the simulation of Bladed,there is no obvious effect on the resistance control under the steady state wind speed,the effect of drag control under turbulent wind speed is better.Drag control of tower and drive chain can effectively alleviate the vibration of the wind turbine and reduce the dynamic load.