Computation of canting errors in heliostats by flux map fitting: experimental assessment Articles uri icon

publication date

  • December 2020

start page

  • 39868

end page

  • 39889

issue

  • 26

volume

  • 28

International Standard Serial Number (ISSN)

  • 1094-4087

abstract

  • In solar tower plants, thousands of heliostats reflect sunlight into a central receiver. Heliostats consist of a subset of mirrors called facets that must be perfectly oriented (i.e., canted) to concentrate as much solar radiation as possible. This study presents and validates the so-called flux map fitting technique to detect and correct canting errors. The computed distributions were matched to a series of images through an optimization algorithm. According to the sensitivity analysis, three images spread along a single day provide sufficient information for the algorithm to succeed. Using this methodology, four heliostats at the THEMIS research facility were recanted, thereby substantially increasing the optical quality in three of them. The procedure to infer the heliostat aimpoint was assessed.

keywords

  • central receivers; experimental assessment; fitting techniques; flux maps; optical qualities; optimization algorithms; research facilities; solar tower plants