Abstract: In actual installation,the main shaft of the fixed bracket will block the back of bifacial PV module in a certain extent.Therefore,this paper established a view factor model based on the light cross detection algorithm to quantify the irradiance on the rear side of bifacial PV module in a more detailed manner. The non-uniform irradiance is mainly reflected in the different irradiance of each cell. This paper refined the thermoelectric coupling model to the cell side to solve the mismatch loss calculation of the bifacial module under the back shielding condition,and completed the modeling of bifacial PV module under complex working conditions. Finally,combined with the investigation case,the power generation and economic efficiency of three spindle structures of the fixed brackets on bifacial PV array were compared. Combined with the investigation case,taking 15 years as the investment cycle,the power generation and economy of double-sided photovoltaic array under three main beam structures of fixed support（conventional support,double main beam support and single main beam support）are compared. Finally,it is concluded that the annual power generation gain of doublesided photovoltaic array with single main beam structure support is the largest and the economic benefit is the best.