The Study Of Photovoltic Module Structure Optimizing Caused By Hot Spot Under Partial Shading

During the work time,photovoltaic array is sometimes affected by the surrounding buildings,especially in the area with dense buildings,trees,stains and so on.And it will lead to power loss,mismatch in PV array and hot spot,even result in irreversible damage to PV cells,economic loss and accident.So it is vital important to improve the output power and avoid the hot spot for the reliability of PV generation system.To avoid the PV array mismatch and power loss under partial shade,the main contributions are as follows:1.The mathematical model of PV cells is built based on the equivalent circuit of PV cell.Under different conditions between partial shade and no partial shade,the output characteristic of PV array is analyzed under the conditions of different light and temperature.2.In order to acquire the effect about different structure to output characteristic,the output characteristic of PV array under different structure in same partial shade is studied.The tract to maximum power point of output is based on the fuzzy control,in order to make the output power stable at the maximum power point.3.According to the scene reduction technology,optimizing structure algorithm is put forward by changing the PV array connection.Through calculating the difference between different short circuit current under partial shade,the shading approximation of PV cells can be got,and classifying the similar shading cells in series to the same branch to optimize the structure of the array.The algorithm as above is achieved by programming.Through comparing optimizing structure with other examples,the superior of the algorithm is analyzed compared with the original structure.