Design Of A Tilted Single-axis Intermittent Solar Tracking System

Photovoltaic power generation has apparent effect on making improvement for the problem of energy shortage and environment pollution.Currently,the common photovoltaic power generation system mainly consists of fixed system,manually adjustable system and tracking system,among which most researchers focus on the tracking system due to the most on increasing the solar radiation received by solar energy cell.However,the operational instability and high cost make the tracking system be difficult to be popularized.Based on the problem,an intermittent tracking scheme on the basis of tracking system is proposed.The tracking system is simplified by losing a small amount of solar radiation for lowering the requirement of high precision hardware,which not only enhances the conversion efficiency,but also reduces the cost,and improves the stability of the system.The intermittent tracking scheme designed in this paper is using linkage tilted single-axis tracking support as the carrier.Firstly,the computational formula of solar altitude angle and the azimuth angle is derived by using spherical trigonometry and the deduction process,which can be used to the algorithm correction and control optimization of the tracking system in practical application.Then,based on the Kastrov expression and Berlyand theoretical expression,the thesis calculates clear-sky irradiance,the corresponding parameters of that are obtained by fitting of actual radiation observation data through Origin software.Next,the polygon-like model of tilted single-axis tracking is established to calculate the solar radiation received by PV cell panel by use of the integration of irradiance,and the calculation results are used to confirm intermittent tracking scheme by combining the output power simulation experiment of indoor solar energy cell.Lastly,taking Xi'an as example,the thesis designs tilted single-axis intermittent solar tracking system,and the result shows that when the installation angle of tilted single-axis is 30 degree and the daily movement of cell panel is 25~27(The number of times of movement in different seasons is different),the wrong move and cumulative error of the tracking system will be effectively reduced and solar radiation received by cell panel is 20%~35% higher than that received in fixed system of the same inclination degree,and only 0.2%~0.33% less than the continuous tracking.The thesis designs tracking scheme of intermittent tracking system,which could provide guidance to the writing of tracking controlling program,moreover,the confirmation of tracking rotation angle can be use to offer parameter basis for the hardware selection.Innovative points:1.Proposal of intermittent tracking to enhance stability at the expense of a little radiation energy loss;2.Establishment of polygon-like model for the process of intermittent tracking;3.Designation and adoption of indoor stimulation experiment to investigate the influence of the small angle deflection of solar cells on output power.