IoT Network and Sensor Signal Conditioning for Meteorological Data and Photovoltaic Module Temperature Monitoring

Abstract

The present paper describes the design, development, implementation and testing of an Internet of Things (IoT) network with sensors signal conditioning circuits for monitoring decentralized photovoltaic (PV) plants. The system intends to reduce costs of commercial data loggers and sensing modules which require control and data storage using proprietary software. We applied our IoT monitoring network in three PV plants installed in Fortaleza and Maracanaú cities, in Brazil and Cologne, Germany. The embedded systems are based on free software and hardware and communicate with a Cloud server via WiFi. Web Monitor was developed in PHP for online and real-time data consultation in form of charts. The main objective is to measure PV module temperature, providing data for the analysis of PV module’s efficiency and for fault detection in case of PV cells overheating. Solar irradiance, ambient temperature, relative air humidity and wind speed are also monitored, allowing more information to analyze the effect of meteorological parameters on the PV module’s performance. Finally, we validate our temperature conditioning system with a commercial equipment and the correlation obtained is about 0.9989.