Research On Sorting Simulation Program And Auto-optimizing Sorting Strategy Of Crystalline Silicon Solar Cells

In order to decrease power losses of photovoltaic module caused by mismatched electrical parameters of the interconnecting solar cells encapsulated in module, and improving manufacturers’ capacity of photovoltaic module which meet the demand of market on particular power rating, the demands of the photovoltaic enterprises for quickly drawing out effective sorting strategy of solar cells are ever growing. The research subjects of this thesis are composed of a computer simulation program and an auto-optimizer sorting strategy on solar cells sorting, which mainly focus on the simulating sorting process of solar cells, the way boundary conditions of bins influencing power distribution of modules and the search algorithm which can quickly find the best bound of each bin.Base on the power loss mechanism of mismatched solar cells and the calculation principle of solar cells sorting, this thesis presents a solar cells sorting program which programed by the VBA language, and a simulation analysis on the power distribution of solar module that sorted by normal sorting strategy.According to the simulation results, the solar cells sorting program is exactly able to analog the process of cells sorting and module power calculation. By putting a two-orders sorting strategy of Hanwha into the sorting program, solar cells will be ranged to particular bin according to the sorting strategy, and the statistical distribution of solar cells and average efficiency will be presented. Then simulation on realistic process of modules packaging follows, where solar cells on each bin will be randomly selected into a module combined with 60 pieces of solar cells, followed by power of each module, statistical power distribution of each bins and the whole batch of modules. Compared with the realistic power distribution of Hanwha, it can be concluded that the sorting program is able to accurately analog the process of cells sorting.Research on the effect of sorting strategy on power distribution is also presented by the sorting program on this thesis. According to the results of sorting experiment, in one-order sorting strategy, by increasing the lower efficiency the module power will be shifted to higher power regions. In addition, it can be figured out that there are four kinds of one-order bins according to the difference of modules power distribution, which makes the quick optimizing program of two-orderssorting strategy becomes possible.The calculated results show that the cells auto-optimizing sorting program is able to quickly formulate a sorting strategy which meets the user’s requirement. Compared with the sorting strategy of Hanwha, the optimized one can move more modules to 245 and 250 W ranges, where the proportion is increased by ten percent respectively, while the proportion of 240 W decreased by one fifth. Obviously, the auto-optimizing sorting program is helpful in improving sorting process and benefit of module manufactures significantly.