PV Plant Equipment Labels and Layouts Can Be Validated by Analyzing Cloud Motion in Existing Plant Measurements

Large-scale photovoltaic plants collect monitoring and operational data at various spatial scales within the plant (e.g., strings, combiners, and inverters). Manual validation of the spatial position of these plant segments relative to the plant design requires on-site observations that may be prohibitively costly or labor intensive. This article presents a methodology for validating plant segment position based on operational data from the plant. By observing the delay between segment responses to cloud motion, predictions of their relative positions within the plant can be made. The method was demonstrated on combiner-level data from a 20-MW, operational photovoltaic plant in the United States. Several instances of apparently mislabeled combiners were identified from the analysis. A partial validation of 20 combiners was conducted by inspecting the plant, with results showing complete agreement between observation and predictions. Predictions derived from this methodology can serve as the basis for further plant inspection and corrective maintenance.