一种基于光伏阵列开路电压估算太阳能抽水系统中退化光伏组件的简易方法

Abstract Four regression methods are presented to estimate the number of highly degraded solar panels per string affected by severe potential-induced degradation (PID) from the open-circuit voltage measurement of the string. Three case-study plants, initially affected by PID and evolving into additional problems, are shown. In the tenth year of operation, the plants’ energy production dropped 67.58%, 47.22% and 32.06% below the average annual production in the four first years. The plants are on the roof of agro-industrial facilities, supply power to irrigation pumping systems, and are subjected to high temperatures and humidity. The proposed method solves a heat stress health safety problem, prevents water supply failures, and estimates the size of repowering purchases. Days with very high temperatures are the best times to detect PID in the field but they represent a safety problem for the maintenance workforce in very hot areas. The method is fast and it is not necessary to reach the roof. The methods were also designed and used to estimate the number of degraded panels to be replaced, proceeding to purchase orders based on these estimates. Significant adjusted R 2 values between 0.64 and 0.82 were obtained depending on the regression method used.