Evaluation of Heliostat Field Global Tracking Error Distributions by Monte Carlo Simulations

Modeling of Drift Effects on Solar Tower Concentrated Flux Distributions

“…This may be particularly accentuated for large incidence angles, that is, very inclined heliostats (large ) or nonflat receivers. However, as has been discussed elsewhere [9], for north field configurations with flat receivers, the distance between these points is relatively small in comparison with the displacements caused by drift. For other kinds of configurations the model should be further developed.…”

“…Heliostat control requires adjusting the angles of the tracking mechanism according to calculations in such a way that the heliostat normal vector bisects the angle between solar vector and relative target position vector [7]. However, this task is subject to many errors [8][9][10][11][12][13][14][15][16]. Drift is defined as the wandering of the concentrated light spot produced by a heliostat.…”

“…The different types of drift and their causes have been discussed in detail [8,17]. This leads to a statistical distribution of tracking errors that has been shown to differ from the conventional Gaussian behavior [9].…”

“…In the present work a rigorous geometrical model of drift behavior [8,9] is coupled to the very fast heliostat flux model described above [20]. This allows developing a method to study the dynamic behavior of the flux distribution, including its uniformity and average distribution.…”

Evaluation and measurement of heliostat misalignment in solar power plant using vector model

“…In [5], Jones and Stone shows the calculated positions of the heliostat beam on the target at 1-hour increments, implementing fixed values for three main types of geometric error sources: encoder reference offset, mirror alignment and heliostat tilt. In [6], Díaz-Felix et al simulated tracking errors by adding an angular deviation angle to the vector normal to the heliostat, in azimuth or elevation, relative to its ideal orientation. Numerical results are also shown, illustrating daily drift trajectories for a fixed value of the deviation angle.…”