Research Of The Control Of Wind Turbine Tower Side To Side Vibration And The HSMC In The DFIG

With the shortage of energy resources such as oil and coal,and along with the pollution, people have to find new energy resources. Wind energy as one of the renewable energy, the maximizing efficiency of capturing it and connecting it to the grid is the goal of many countries go after.In the first part of the thesis, The VSCF wind turbine is modelled and emulated with the tool of MatLab/SimuLink. The operating principle of VSCF WT and the control targets are analyzed. The technical condition of vibration control of tower at home and abroad,Under the rated wind speed operating conditions of the WT, the maximum wind power capturing is achieved using the optimal power tracking method, and the influence of electromagnetic torque on the side to side vibration of the tower is analyzed and the emulating model is set up.The controlling of the generator electromagnetic torque is easier to achieve, we use acceleration sensor to get the feedback of speed and displacement of tower's top, and place poles of the system to change its natural frequency and damping. Simulation results show the effectiveness of the method, and it is pointed out that the method requires improvement.In the second part of the thesis, the operating principle of the double-fed induction generator (DFIG) is presented. Its mathematical models in different coordinates are analyzed. The decoupling control of active and reactive power is achieved using space vector transformation technology and stator flux orientation. Then the knowledge of sliding mode control is introduced.For nonlinear characteristics of DFIG and the chattering phenomenon, the higher order sliding mode control is applied to the DFIG control, the 2rd sliding mode controller based on non-singular terminal sliding mode surface is designed,the results contrasting with the classical sliding mode controller based on index reaching law, shows that this conteroller can achieve good control targets and suppress the chattering effectively.In the last, the summarization of the thesis is made, and some study ways are put forward.