Soiling measurement system for photovoltaic arrays

摘要

A system for measuring the power or energy loss in a photovoltaic array due to soiling, which is the accumulation of dust, dirt, and/or other contaminants on the surfaces of photovoltaic modules, comprising: a pair of photovoltaic reference devices placed within or near the photovoltaic array and co-planar to the modules comprising the array, wherein one reference device is a module similar to those of the array and is allowed to accumulate soiling at the natural rate, and wherein the second reference device is a module or a cell and is periodically cleaned; and a measurement and control unit which measures and compares the electrical outputs of the soiled reference device and the clean reference device in order to determine the fraction of power lost by the soiled reference module due to soiling.

主权项

1. A system for measuring electrical output loss in a photovoltaic array due to soiling, comprising:
a pair of photovoltaic reference devices placed substantially proximate to the photovoltaic array and substantially co-planar to modules forming the array, said pair of photovoltaic reference devices comprising:
a first reference device, designated as a soiled reference device, comprising a photovoltaic module representative of a portion of the photovoltaic array, wherein the soiled reference device is allowed to accumulate soiling at a rate representative of the rate of soiling of the photovoltaic array;a second reference device, designated as a clean reference device, comprising a photovoltaic module or cell, wherein a sensing surface of said clean reference device is maintained substantially clean and free of accumulated soiling; a measurement unit for performing measurements of a subpart, wherein said subpart comprises said soiled reference device, said clean reference device, and combination thereof;
wherein said measurements of the soiled reference device comprise measurements of a short-circuit current, a maximum power output, and combinations thereof; andwherein said measurements of said clean reference device comprise measurements of said short-circuit current; and a computing device, wherein said computing device analyzes said measurements associated with said subparts for determining a soiling impact analysis.