Study On Control System Of Solar Tracker Based On Spherical Mechanism

Scientists generally accept that for mankind the solar energy is the fittest, the most safe, the most green and the most ideal replaceable energy in future .The current solar energy converting rate roughly is 10% ~ 20%.Analysis indicated that adopting the solar tracker can increase 37% the rate of receiving energy .Research and development of the two axes solar tracker can increase the reception efficiency and open widely the exploitation realm of the solar energy.The studying content in this paper is control system of solar tracker based on spherical mechanism.The device adopts parallel 3-DOF spherical mechanism, realized tracking to the solar azimuth and altitude angle in real time, the redundant degree of freedom has increased systemic rigidity.Deduced the position and posture inverse solution of the spherical mechanism .given the device's input angle.And to the job requirements for the solar tracker, have put forward the control scheme of making use of single-chip computer to realize tracking in real time.The system adopted active tracking,namely calculate the input angle of the tracking device in advance,the angle is correspondent to the sun position some moment.Photoelectric sensors react the sunlight that putting on different position of the platform, feedback electrical signal.Then single-chip applys the subprogram and sends out pulse to step motors according to the signals,can control the rotate angle and direction of the step motor. The mechanism has realized the automatic track to the sun, so that the tracker's top flat board can be always vertical to the sunlight and arrive the furthest receiving energy. Systemic hardware select At89c51 (compatible with Intel Company MCS-51 series), it is used as control core to control the executive part—step motor. Have finished the design of the peripheral hardware circuit of single-chip and design of the corresponding software. This driver adopted the special compositive module related to the step motor.It has the character of strong anti-jamming,good performance of high frequency,simple construction and running steadily etc.