Research On Dual-motor Anti-backlash Control System With High Precision For Large Heliostat Driver

In recent years,with the deep research and development of new energy sources,solar energy has attracted more and more attention because of its abundant reserves,green and non-polluting.As one of the ways of using solar energy,tower solar thermal power has become an important direction of the development of new energy sources with its low cost,high efficiency,without blocking,etc.Compared to the small heliostats,large heliostats have many advantages such as lower cost of investment and higher power efficiency,so it is the inevitable trend of the development of solar thermal power.But high tracking accuracy and high cost of driving system are restricting the rapid development of large heliostats.Nonlinear backlash of driving system is one of the important factors affecting the heliostats tracking accuracy,so the research of driving system anti-backlash control plays an important role in the development of large heliostats.Based on large heliostats tracking control system as the background,aiming at the problems of high cost and easy damage of driving system,a dual motor driving mechanism on rotating direction is designed.On the basis of this,a composite angle detecting device based on magnetic field and gravity detection is designed.And aiming at the nonlinear backlash of drive system,we presented the hysteresis nonlinear model by its motion characteristics,and distributing strategy of dual motor anti-backlash torque and three closed loop controller of position,speed and current are also designed.In order to verify the feasibility of the project,an experimental platform is built,which includes the position detecting module,the controller,the weather station and the MCGS upper monitor,which realized the application of dual motor anti-backlash in the actual tower solar thermal power tracking control system.The experimental results show that the dual motor driving mechanism can reduce the cost of system and improve the capability of anti-wind greatly,Besides,the composite angle detecting device and the dual motor anti-backlash control system can meet the requirements of control precision of the heliostats tracking system.