Integration of an On-Axis General Sun-Tracking Formula in the Algorithm of an Open-Loop Sun-Tracking System

Abstract

A novel on-axis general sun-tracking formula has been integrated in the algorithm of an open-loop sun-tracking system in order to track the sun accurately and cost effectively. Sun-tracking errors due to installation defects of the 25 m2 prototype solar concentrator have been analyzed from recorded solar images with the use of a CCD camera. With the recorded data, misaligned angles from ideal azimuth-elevation axes have been determined and corrected by a straightforward changing of the parameters' values in the general formula of the tracking algorithm to improve the tracking accuracy to 2.99 mrad, which falls below the encoder resolution limit of 4.13 mrad.

Performance study of crossed compound parabolic concentrator as secondary optics in non-imaging dish concentrator for the application of dense-array concentrator photovoltaic system

“…error ranging from 0°to 0.4°with increment of 0.1°. The choice of range for pointing error takes into consideration of practical tracking accuracy as if a 12-bits optical encoder is employed as feedback sensors in the tracking algorithm (Chong et al, 2009a(Chong et al, , 2009b. After setting all the parameters for primary concentrator, secondary concentrator and receiver planes, the ray-tracing program is initiated to plot the flux distribution pattern on the receiver planes for both NIDC and exit apertures of CCPC lenses.…”

The Logic-Based Supervisor Control for Sun-Tracking System of 1 MW HCPV Demo Plant: Study Case

“…Facilitating formula, position counters and control methods according to the sun ephemeris, enable the solar tracker to aim at the sun. This is called open-loop control [5]. The other method of sun tracking is by using the sun position sensor to detect and maneuver the solar tracker.…”

General Formula for On-Axis Sun-Tracking System

“…Not all these orientation angles can be precisely obtained due to the limitation of measurement tools and the accuracy of determination of the real north of the earth. The following mathematical derivation is attempted to obtain analytical solutions for the three orientation angles based on the daily sun-tracking error results induced by the misalignment of sun-tracking axes (Chong et al, 2009b). From the Eq.…”