Real-Time Control and Performance Analysis of PLC-SCADA Supervised Stand-Alone Solar Tracking Systems

This paper presents the real-time control of single-axis and dual-axis solar tracking systems, as well as monitoring of a fixed solar panel system, using PLC (Programmable Logic Controller) and SCADA (Supervisory Control and Data Acquisition). The systems were designed using a novel tracking mechanism and a novel energy generation evaluation method. Based on their efficiencies as well as the power they produced, these three solar panel systems were compared accordingly. In all three systems, identical solar panels having 100 Wp power were used. To control both single-axis and dual-axis solar panels efficiently, an S7-1200 type PLC was employed. Real-time clock and astronomical data were used to control the axis angle of the PV panels. The system was comprehensively monitored and controlled in real-time through the implementation of PLC-SCADA software. The obtained data were recorded and displayed on SCADA screen, and were subsequently analyzed to determine the power output of the three panels under varying climatic conditions. The evaluation of the obtained results was made accordingly. In a total of 61-day period which encompassed 42 days of sunshine, 11 days of cloud and 8 days of rain, double-axis photovoltaic panel produced 337.34 Wh, single-axis photovoltaic panel generated 314.32 Wh and fixed photovoltaic panel produced 220.49 Wh on average. On daily average, double-axis photovoltaic panel produced 7.32% more energy as compared to single-axis photovoltaic panel and 52.99% more energy as compared to fixed photovoltaic panel, whereas single-axis photovoltaic panel produced 42.55% more energy than fixed photovoltaic panel.