Design of compound solar tracking controller
                                                              ZHANG Xiao jun, YANG Jia qiang, WANG Jun jie
                                （College of Electrical Engineering, Zhejiang University, Hangzhou 310027, China）

Abstract: Aiming at the single inclined uniaxial solar tracking system has low tracking precision, tracking accumulated error exists, affected by the weather and poor stability problems, the trajectory and photovoltaic solar array tracking trajectory mathematical model was established, which proposed depending on the day trajectory coarse tracking （error 2°） at this time, then through two quadrant silicon photocell light sensors to realize accurate tracking （error correction to within 0.5°）. A 2.25 kW diagonal tracking device was used to verify and test the proposed compound tracking model. The results indicate that the proposed composite tracking mode can make the system tracking error within 0.5°, PV array output 26.2% higher than fixed photovoltaic array output, and it can eliminate the accumulated error, to overcome the weather affect, realize the all weather reliable operation, which to improve the tracking precision of PV tracking system and photovoltaic power generation is of great significance.

Key words: inclined single axis; light sensor; composite tracking