Research and Design of Sun Tracking Controller By Using Short-Circuit Current of PV

• Main Authors: Chein-ren Chou, 周建仁
• Other Authors: Pi-cheng Tung
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/63762966530798389939

碩士 === 國立中央大學 === 機械工程研究所 === 99 === 　　The output power of the solar cell varies with the varying incidence angle of the sun, so the PV panel must be kept facing the sun directly at any time if we want to rise its output power. Recently, the requirement of tracking error of angle is more and more strict with the development of High Concentrated PV. In general, either photo-sensor or sun trajectory formula is adopted in the controller for sun tracking, but the controllers works on the premises that, the error of mechanism set up should be small, the orientation should be fixed accurately, and the mechanism will be aging after using a long time, so the system should be calibrated and maintained usually. Even though the tracking results are precise, many things were then sacrificed, this will cause the cost of electric-power-generating to be more expensive. 　　This thesis uses the short-circuit current of a solar cell which has a small output power to be the consideration in order to do tracking, the short-circuit current is then measured fast during the process of the operation of DC-DC converter. Thus, the error of mechanism set up and the orientation-fixing accuracy need not to be considered, and the tracking angle that the PV outputs maximum power will still be met. The exact fixing of photo-sensor and the using of encoders will then be left out and the unnecessary cost of calibration and maintenance will be reduced in this way. The tracking performance of the used controller is pretty good in a small range of angle when it is used for the High Concentrated PV system.