Research On Active Control Of Torsional Vibration In Wind Turbine Drive Train

In recent years, the energy crisis and global climate change are raising concerns about clean energy, and wind power technologies has become one of the more mature technology.With the rapid development of wind power, wind turbines are also developing towards larger scale, the operating environment of the unit is more severe, and the load situation is more complex, which is more important for the load control in wind turbine operation. The failure caused by the gearbox will cause the unit to stop for a long time and lose the power generation. Therefore, the research on the torsional load control of the drive train is very important to the safety and the stable operation of wind turbine. The main contents of this paper are as follows:(1) Firstly, the torsional vibration model of wind turbine drive train is established. By analyzing the component models of wind wheel, shaft, and gear pair, a two-mass block model of the drive train is established. In this paper, the concentrated mass model of the multi-shaft system of the drive chain is established. The transfer matrix method is used to solve the natural frequency and the inherent vibration mode. This method can accurately analyze the inherent characteristics of the system and more accurately reflect the force of each section on the axis of drive train, in order to provide the theoretical support for optimization of drive train structure design.(2) The torque control strategy of WTG is introduced, and the torsional vibration characteristics of drive train are analyzed. It is explained that the torsional vibration can be effectively controlled by controlling the electromagnetic torque than the mechanical torque.Based on this analysis, two types of torsional vibration controller are designed. One takes generator speed as signal, by adding band-pass filter, notch filter and the proportional control, with the aim of increasing the damping effect of the drive train and realizing the active resistance control of the torsional vibration of the drive chain. The other adds the Kalman filter state observer based on the traditional drive damping controller, an additional disturbance torque is added to the generator electromagnetic torque to realize active resistance control of the drive train with taking torsional angular velocity as signal.(3) Taking a 1.5MW doubly-fed wind turbine model as an example, the MATLAB software is used to simulate and solve the inherent characteristics and torsional stress. A wind turbine model is built by using GH Bladed. According to the design of the traditional torsional vibration controller and the addition of the Kalman filter observer, the dynamic torsional vibration control of the drive train is simulated to verify the control effect of the two controllers above the rated wind speed, and to compare the control effect. The results show that the torsional vibration damping controller with the Kalman filter has better effect of resisting resistance, and the generation capacity is not significantly affected.