Autori: Alexandru, C.
Editorial: The Scientific World Journal, 2013, p.1-12, 2013.
This paper approaches a dual-axis tracking system that is used to increase the photovoltaic efficiency by maximizing the degree of use of the solar radiation. This is an equatorial tracking system, with two DC motors that drive speed reducer worm gears. The innovative aspect in the control system design consists in considering the tracking mechanism as a perturbation for the DC motors. The goal is to control the DC motors, which are perturbed with the motor torques whose computation is based on the dynamic model of the mechanical structure on which external forces act. The study is performed by developing the virtual prototype of the tracking system, which is a control loop composed by the multi-body mechanical model connected with the actuating & control system model. The daily and elevation (seasonal) angles of the PV module represent the input parameters in the mechanical device model, while the outputs transmitted to the controller are the torques that perturb the DC motors. The controller tuning is approached by a parametric optimization process, using DOE (Design of Experiments) and RSM (Response Surface Methodology) techniques in a multiple regression. The robustness of the control system has been verified by using the experimental model of the solar tracker. The results demonstrate the operational performance of the system, without the need to use complex/expensive in-cascade control strategies.
Cuvinte cheie: PV module, solar tracker, control system, virtual prototype, experimental model