Solar.q_1: A new solar-tracking mechanism based on four-bar linkages

Abstract

This paper describes the early stages of the design process of a 2--DOF parallel mechanism, based on the use of 4--bar linkages and intended to move photovoltaic panels in order to perform sun tracking.Primary importance is given to the search for a way to compensate sun--earth's relative motions with two decoupled rotations of the panel. This leads to devise a kinematic struc-ture characterized by a particular arrangement of the revolute axes. At the same time, the structure itself is designed in order to be slender. Subsequently, the fact that during a day the earth's revolution around the sun has negligible effects on the apparent trajectory of the sun, if compared to the rotation around the polar axis, leads to choose a control strate-gy which, also thanks to the said arrangement of axes, employs only one DOF for most of the daytime. By means of computer simulations is proved that, so doing, are obtained neg-ligible tracking errors. The tracker which employs this strategy has, theoretically, an ener--Proc IMechE Part A: Journal of Mechanical Engineering Science 0(0) gy consumption similar to that of 1--DOF solar trackers but a precision similar to that of 2--DOF ones. KeywordsSolar--tracking mechanisms, 4--bar linkage, sun trajectory, kinematic analysis and simula-tion.

Kinematic Analysis of 4 Bar Mechanisms Applying for Solar Tracking

“…The fullscale prototype is built by integrating a solar panel using a worm screw reducer coupled to the electric actuator connected to the crank. Similarly, [27] constructs a 2-DOF solar tracker using two pairs of offset crank-rocker mechanisms to generate movement. The actuators are equipped with a drum that winds a metal cable, transmitting motion to each degree of freedom.…”

“…The actuators are equipped with a drum that winds a metal cable, transmitting motion to each degree of freedom. The kinematic equations of motion are not presented in [27].…”

One Year Experimental Evaluation of the Electrical Gain by Solar Tracking a 12 KW Photovoltaic System Installed on a Building Rooftop

“…To mitigate this issue, solar tracking systems represent a solution to increase the amount of the received solar energy and the energy output [7]. Several types of solar tracking systems are reported in literature, many of azimuthal type [8], equatorial type [9] and pseudo-equatorial type [10], with yearly output increases up to 35% for tracked solar thermal collectors [11] and up to 30% for tracked PV modules [12]. To the best of our knowledge, experimental results over large period of time are not presented in the literature, only numerical simulations and experimental results over short periods of time of one day [13][14][15] or two days [16] are usually outlined.…”