Photovoltaic performance of one axis multiple-position sun-tracked PV panels

摘要： In this article, the photovoltaic performance of one-axis multiple-positions sun-tracked photovoltaic panels (MP-PV) is investigated based on solar geometry and dependence of photovoltaic conversion efficiency on the incident angle (IA) of solar rays on PV panels. For such PV system, the azimuth angle (AZA) of PV panels is daily adjusted several times (M) from eastward in the morning to westward in the afternoon by rotating PV panels about inclined north-south axis (INSA) to ensure the projected incident angle (PIA) of solar rays on the plane perpendicular to INSA is always less than the specified angle θa. Results show that, the annual electricity generation (AEG) of MP-PV increases with the increase of M, but such increase is not noticeable when M>5. For MP-PV with the tilt-angle (β) of INSA being yearly fixed (1T-MP-PV), the optimal θa of 3P-,5P- and 7P-PV for maximizing AEG are respectively 24o, 15o and 11.5o, and their AEGs are respectively about 92%, 94% and 95% of that from similar 2-axis tracked PV panels (2A-PV). Whereas for MP-PV with the β being yearly adjusted four times at three tilts (3T-MP-PV), the optimal θa of 3P-, 5P- and 7P-PV are respectively about 22.5o, 14.5o and 11o, and the Pa are respectively about 96%, 98% and 99% of that of similar 2A-PV systems.