Abstract
Based on analyzing the development and the performance feature of existing solar tracker, we propose a solar Maximum Power Point Tracking (MPPT) strategy which combines photoelectric sensor and image processing. Firstly, photoelectric tracking mode positions the sun in the field of view of the image sensor. Then, the position of the sun image is captured by the image sensor. After that, we can find the coordinates of the sun spot in the field of view through image binarization processing. According to the number of steps of stepper motor rotation which is calculated by the deviation of coordinates, the controller drives the biaxial photosensitive (PV) array tracking device, making the sun spot always fall in the centre of the image. Tests show that the elevation angle and azimuth angle of the tracking range of the photovoltaic array are both 0～270°.The average tracking error of elevation angle is less than 0.7°, and the average tracking error of azimuth angle is less than 0.5°.
Publisher
Trans Tech Publications, Ltd.
Reference9 articles.
1. Zekai Sen. Solar energy in progress and future research trends [J]. Progress in Energy and Combustion Science, 2004, 30(4): 367-416.
2. Luo Yunjun, He Zainian, Wang Changgui. The use of Solar Energy technology [M]. Chemical Industry Press, (2005).
3. AL-Soud M S, Abdallah E, Akayleh A, et a1. A parabolic solar cooker with automatic two axes sun tracking system [J]. Applied Energy, 2010, 87(2): 463-470.
4. Zhang Haiyan, Zhang Chongwei, Wang Jianping. The research on coordinated control method of capturing the maximum degree of sunshine [J]. Acta Energiae Solaris Sinica, 2008, 29(11): 1338-1341.
5. Yacov Tsur, Amos Zemei. Long-term perspective on the development of solar energy[J]. Solar Energy, 2000, 68: 379-392.