Structural Stablility Control Analyss Of Floating Wind Turbine With ETMD And TMD-NES

Due to the complexity of its environmental load,offshore floating wind turbines are prone to instability and even overturning,which directly affects the power generation and life of the wind turbine.It needs to be controlled to ensure smooth operation and iincrease reliability.In this paper,the 5MW Spar wind turbine is taken as an example to establish the dynamic model under the action of wind,wave and flow loads.The control strategy of Extended Tuned Nass Damper(ETMD)is proposed and the influence of various parameters of the systme stabilityis analyzed.The active control method is used to effectively control the surge response of the wind turbine tower.Finally,nonlinear elements are added to study its dynamic characteristics The specific content includes:Firstly,the environmental load of the floating wind turbine is calcu ated.The aerodynamic model of the wind wheel is simplified and the aerodynamic load of the wind wheel and the tower is calculated by the one-dimensional momentum theory.The velocity and acceleration of the water point are calculated by Airy wave theory.Combined with the Morison equation,the wave load on the floating platform and the flow load on the floating platform are obtained.Secondly,for the Tuned Mass Damper(TMD),the tuning frequency is narrow and the space is large",the ETMD control strategy is proposed.The dynamic model of floating wind turbine with ETMD is established,and the dynamic response of the system is solved by the vibration mode superposition method.The effects of mass ratio,damping ratio,frequency ratio on dynamic amplification factor and frequency modulation width betwees ETMD system and tower are analyzed.The genetic algorithm is used to optimize the parameters of the objective function,and the control effect of the optimized ETMD is compared and analyzed..Thirdly,for the servo motor control response problem,the inner and outer loop control strategy is adopted.Tte outer loop is calculated by the active control algorithm to calculate the target power.The inner loop controls the current output to actually power,so that the inner loop motor output force smoothly tracks the outer loop for power.The outer loop part is designed with a Linear Quadratic Regulator optimal controller.(LQR)controller to control the stability of the tower’s surge response;In addition,Sliding Mode Control(SMC)is designed to realize the design and simulation of the Expanded Active Tuned Mass Damper(EATMD)control system for reducing the dynamic response of the wind turbine tower,and evaluated the control effect of EATMD control system under SMC.The inner loop part uses the vector control method to control the permanent magnet synchronous linear motor current to achieve the purpose of fast and smooth tracking control target.Finally,a damping method of Tuned Mass Damper-Nonlinear Energy Sink(TMD-NES)hybrid control is proposed.The dynamic model is established.The dynamic response of the system is solved by the complex variable averaging method.The stability of the equilibrium point is analyzed based on Lyapunov theory.The correctness of the analytical method is verified by numerical method.The system bifurcation behavior of external excitation amplitude and NES nonlinear stiffness variation is discussed.The vibration suppression effects of uncontrolled,single TMD,single NES and TMD-NES hybrid control are compared and analyzed.