Research On The Key Technology Of High Efficiency Solar Cell

With the reverse of fossil fuel is decreasing day and day. At the same time, awareness of the importance of protecting the global environment is growing. So searching for pollution-free replacer of fossil resources becomes more and more urgent. Solar energy as Renewable is pollution-free and inexhaustible. So it has broad application prospects, and photovoltaic generation technology was got more and more attention. In order to gain ground the photovoltaic products, the trend for the development of solar cell is to further improve the efficiency and lower the cost . The key of improving the conversion efficiency of solar cell and reducing costs is to improve the utilization of solar energy. Concentrating solar cell can effectively improve the conversion efficiency of cell and reduce costs. Thereinto, concentrator designing and tracking technology are the key technology in study of such batteries.In this thesis, the working principle, basic structure and key characteristic of solar cell are introduced in detail. Based on this, the concentrator of concentrating system is researched and designed. The main contents are as following.(1) Analyzed the conversion efficiency and its influencing factors of solar cell. Furthermore, researched the main technology of improving conversion efficiency of solar cell, as the technology of antireflection loss, reduce loss of carrier and reduce loss of optical transmission.(2) Researched several typical concentrating solar cells and concentrator applying in solar cell. By analyzing and researching, it is known that the manufacturing costs of parabolic concentrator are high and reflective layer is easy to fall off, and the Fresnel lens have better performance characteristics when applying in solar cell.(3) Designed the cylindrical line focus Fresnel lens and derived calculating formula for confirming the location of battery by analyzing the optical efficiency of plate-shaped linear Fresnel lens. We have do some experiments about Fresnel lens improving the utilization of solar energy by using punctuate Fresnel lens(32cm×25cm) and digital luxmeter model as ZDS-10H . As a result ,the solar illuminance of unit area was increased by 15.3 times. According to the experimental datas, it is validated that Fresnel lens as a refracting concentrator can significantly improve the utilization of solar energy. However, the concentrating multiples of concentrator are smaller by weakening of light intensity, and decreased by in increasing of angle of field of view of the sun. The reason is attribute to reflection losses of surface.(4) According to disfigurements of solar concentrator of parabolic column curved surface, such as the focus light is uneven, the high cost of processing and the silver reflective layer easily fall off. A method to improve parabolic reflected concentrator is presented. We use many little pieces of zigzag glasses to replace curved surface and use double silver-plated glass not single. It's a successful way for the use of solar energy with low costs.