Research On Load Control Strategy Of Permanent Magnet Direct-Drive Wind Turbine

Energy is the driving force for economic development,with the rapid economic development and the important role that it has made,energy has become a key factor in industrial development.However,the world is facing a severe energy shortage crisis,the study of the use of new energy that has become the current solution to energy shortages.In the new energy technology research,wind power technology is the most mature and reliable,in the world has been widely used.Wind energy is random and fluctuating,and it is very important to use wind energy effectively.Wind turbine control technology is the key technology in wind power generation technology.The global wind turbine is moving towards large-scale development,the stand-alone capacity becomes larger and the unbalanced load on the key components of the wind turbine seriously affects the efficiency of the wind turbine.In order to improve the efficiency of wind turbines and improve the efficiency of wind turbines,it is more and more important to effectively reduce the unbalanced load caused by wind shear,wind shear and tower shadow effects on key components such as bladesFirstly,the basic theory of wind turbine control is studied,and the blade is analyzed by aerodynamics.The load on the blade is calculated by the momentum-leaf theory.As the wind speed is random,in order to simulate the real wind power when the wind turbine is running,it is necessary to study the normal wind speed and extreme wind speed model.When the wind turbine is running,it can not capture all the wind energy.Only the partial wind energy can be used to track the wind power unit's optimal wind energy utilization factor through the research of the power characteristics of the wind turbine to realize the maximum output power of the wind turbine.Secondly,the method of variable load control,variable pitch control and variable pitch control and variable pitch control of wind turbine.The principle of unified pitch control and independent pitch control of wind turbine is analyzed.It is concluded that the independent pitch can effectively control the load on the blade,and the actuator of independent variable pitch control of wind turbine is analyzed.The unbalanced load on the blade is analyzed and the Coleman coordinate transformation is carried out on the unbalanced load to obtain the pitch moment and yaw moment at the hub,and the control pitch moment and yaw moment can effectively control the unbalanced load of the blade.The mathematical model of the permanent magnet AC servo motor is studied,and the PID variable pitch controller is designed by the mathematical model to realize the independent pitch control of the wind turbine.Finally,the independent variable pitch control system of wind turbine is a nonlinear time-varying system.The unbalanced load changes caused by wind shear,wind shear and tower effect on the blade are complex,and the individual PID controller can not quickly update the control parameters to effectively control the unbalanced load on the blade.Radial basis function neural network with on-line self-learning ability,can be adjusted by the network to adjust the PID control parameters.On this basis,the radial basis function neural network PID independent pitch control strategy is proposed.Through the on-line self-learning of the radial basis function neural network,the PID control parameters are adjusted,and the PID control parameters are adjusted in real time to realize the optimal control of the independent pitch control system,which can effectively reduce the imbalance on the blade The effect of load on the stable operation of wind turbine and improve the service life of fan.