Research On Suspension Control Of Low Wind Speed Maglev Vertical Axis Wind Turbine

At present,the horizontal axis wind turbine(HAWT)is the mainstream product of the high-power wind turbine,but it has some inherent defects such as the yaw system needed,large starting resistance moment,inconvenient installation and so on.Due to the advantages of no mechanical friction,no need of yaw system,low cut-in wind speed and easy installation,the maglev vertical axis wind turbine(VAWT)is especially suitable for weak wind farms and will be the key direction of wind power development in the future.For this reason,a low-wind-speed maglev VAWT is developed by our research group.This paper takes it as the research object,and focuses the suspension control of its maglev system.First,the dynamic mathematical model of the maglev system is established through the mechanical analysis of the maglev system of the aforementioned maglev VAWT.Second,aiming at the established dynamic mathematical model of the maglev system,the BP-PID control scheme is proposed to improve the control performance of the maglev system.Based on the BP-PID control scheme,the simulation experiments of suspension stability and anti-interference are carried out.The results show that the proposed BP-PID control scheme has stronger suspension stability and anti-interference performance and faster dynamic response speed,compared with the air gap single loop PID and the double-loop PID control scheme.Then,the suspension converter system is studied and designed,including the power circuit topology,control mode,rate of current change,current ripple,peak voltage,switching loss and power level and so on.The power circuit design mainly includes parameters calculation and selection of IGBTs,the freewheeling diodes,inductors,capacitors.The control circuit design mainly includes the designs of the current sampling circuit and air-gap sampling circuit,as well as the main controller circuit,PWM signal conditioning circuit and the drive circuit of IGBTs.Finally,the maglev experiment is carried out.A small maglev experiment platform and an experiment platform of H-bridge suspension converter based on d SPACE are built.In order to verify the superiority of the proposed BP-PID control scheme,the suspension stability experiment is carried out by using the single loop PID control scheme,the double-loop PID and the BP-PID control scheme;and the suspension anti-interference experiment is also carried out by using the double-loop PID and the BP-PID control scheme.The comparison of several experimental results shows that the BP-PID control scheme not only has stronger suspension stability,but also has stronger anti-interference performance and faster dynamic response speed.