An Internet of Things—Supervisory Control and Data Acquisition (IoT-SCADA) Architecture for Photovoltaic System Monitoring, Control, and Inspection in Real Time

The Internet of Things (IoT) serves as a key component to enhance operational efficiency and decision-making in the context of supervisory control and data acquisition (SCADA) systems. Featuring the improved system robustness and real-time parameters, including images of the load, a new design of SCADA system monitoring for a photovoltaic (PV) system based on dual IoT platforms is proposed in this paper. Two voltage sensors collect the voltages of the PV module and the battery, while three current sensors accumulate the current data from the PV module, the battery, and the load. ESP32-E assembles the data and then transmits them to the Arduino Cloud via MQTT for real-time display and ESP32-S3 via HTTP. The relay and the load are controlled by ESP32-E to turn ON/OFF based on the battery voltage as well. In addition, ESP32-S3 forwards the received data to ThingSpeak for advanced analysis, data storage, and real-time display via HTTP. The load images are also displayed on a camera web server built by ESP32-S3. Successfully monitoring for over 20 days, the proposed system demonstrated its robustness and versatility even during the downtime of the Arduino Cloud, with a one-day voltage measurement ranging to a maximum of 13 V and current ranging from zero amperes to 4.42 amperes. To add to this system, it incorporates visual load monitoring features, which are unseen in traditional systems.