单轴跟踪式双面光伏系统背面辐照度监测

Abstract Rear plane-of-array (R POA ) irradiance measurements play a critical role in monitoring the performance of bifacial PV systems, yet the industry still lacks a comprehensive set of best-practices for performing R POA measurements. We address this gap by identifying the best locations for R POA irradiance sensors (such as pyranometers) on the back of single-axis trackers (SATs), and by recommending R POA sensor quantities for utility-scale systems. This is accomplished by simulating spatio-temporal light distributions on the back of typical utility-scale SAT designs in nine climates using the opensource Python library bifacial_radiance . We find that by averaging measurements at just two discrete locations on the east and west sides of SATs, the annual R POA error (defined as the deviation to the spatial average R POA irradiance) is approximately 2 % for all SAT types and locations studied. The addition of a third R POA sensor in the average does not decrease this error. For 1P and 2P SATs, we recommend one R POA sensor mounted half-way between the torque-tube (TT) and the east edge (–50 %), and a second sensor placed equivalently half-way between the TT and west edge (+50 %)–with sufficient distance from the north or south edge to avoid edge brightening. We find that these positions have allowable tolerances of ± 10 cm in the east–west direction, and that the recommended positions change by less than 5 cm when variations in albedo, tracker height, ground coverage ratio, and season are considered. Finally, our theoretical results are supported by field measurements from two specialized sensor arrays installed on utility-scale SATs.