Maglev Wind Turbine Yaw Device And Suspension Control Study

Horizontal axis wind turbines become the mainstream style in wind power stations currently. As the important component of horizontal axis wind turbines, the active yaw system makes decisive influence on both service life and work efficiency of generator. When the direction of the wind changes, motors of the active yaw system drive the yaw gears to rotate, the gears drive the head of wind turbine to move and to finish the work of aiming at the direction of the wind. There are some problems in the active yaw system at present, such as too many and heavy mechanical parts, complex structure; transposing lubricant periodically, maintained frequently; many driving motors occupy plenty of yaw system space; the torque of deviating from the center of tube on the head of the wind turbine will make the tube bend laterally and cause the impeller vibrating in the process of yawing.In order to solve these problems of the active yaw system, a solution is presented in this paper, a novel yaw system:Yaw System of Wind Turbine Based on Magnetic Suspension Technique. This yaw system can aim at wind accurately, the simple hardware structure makes it maintained easily, it is seized of long service life and low power consumption.This novel yaw system has a wide range of research contents, the main researches in this paper includes the follows:(1) Based on the electromagnetism theory, the design method of linear motor and disc motor, a maglev performed disc motor is designed.(2) Finite element analysis about the motor's electromagnetic field is made, the model's electromagnetic field distribution is ascertained.(3) The dynamic mathematical model of the suspension system is established, and the relationship between key parameters, such as suspension force, exciting current and suspension gap, is presented, the state-space equation with current as the controlled input variable is derived from the dynamic mathematical model, The control strategy and algorithm for the suspension system are proposed and simulated with MATLAB software.(4) Based on two-quadrant DC-DC chopper with DSP F2812 as its control core and IGBT are designed and developed, processing circuit of air-gap signal and driving circuit of high-power IGBT are designed. The software flowchart is provided, the programming methods of subroutines IIR and PID are interpreted in details.(5) The model of Yaw System of Wind Turbine Based on Magnetic Suspension Technique is developed, maglev experiment is carried out and analyzed.