Direct tracking error characterization on a single-axis solar tracker. (15th November 2015)

• Record Type: Journal Article
• Authors: Sallaberry, Fabienne; Pujol-Nadal, Ramon; Larcher, Marco; Rittmann-Frank, Mercedes Hannelore
• Is Part Of: Energy conversion and management. Volume 105(2016)
• Page Start: 1281
• Page End: 1290
• Publication Date: 2015-11-15
• Subjects: Tracking error -- Single-axis tracking -- Acceptance angle; Direct energy conversion -- Periodicals; Energy storage -- Periodicals; Energy transfer -- Periodicals; Énergie -- Conversion directe -- Périodiques; Direct energy conversion; Periodicals; 621.3105
• DOI: 10.1016/j.enconman.2015.08.081
• Languages: English
• ISSNs: 0196-8904

Abstract

Highlights: The solar tracker of a small-size parabolic trough collector was tested. A testing procedure for the tracking error characterization of a single-axis tracker was proposed. A statistical analysis on the tracking error distribution was done regarding different variables. The optical losses due to the tracking error were calculated based on a ray-tracing simulation. Abstract: The solar trackers are devices used to orientate solar concentrating systems in order to increase the focusing of the solar radiation on a receiver. A solar concentrator with a medium or high concentration ratio needs to be orientated correctly by an accurate solar tracking mechanism to avoid losing the sunrays out from the receiver. Hence, to obtain an appropriate operation, it is important to know the accuracy of a solar tracker in regard to the required precision of the concentrator in order to maximize the collector optical efficiency. A procedure for the characterization of the accuracy of a solar tracker is presented for a single-axis solar tracker. More precisely, this study focuses on the estimation of the positioning angle error of a parabolic trough collector using a direct procedure. A testing procedure, adapted from the International standard IEC 62817 for photovoltaic trackers, was defined. The results show that the angular tracking error was within ±0.4° for this tracker. The optical losses due to the tracking were calculated using the longitudinal incidence angle modifier obtained by ray-tracing simulation. The acceptance angles for various transversal angles were analyzed, and the average optical loss, due to the tracking, was 0.317% during the whole testing campaign. The procedure presented in this work showed that the tracker precision was adequate for the requirements of the analyzed optical system.