Design and Implementation of Multi-function Protection for Distribution Transformer Connected to PV systems

Abstract: Residential rooftop-mounted solar photovoltaic (PV) panels are being installed at an increasing rate, worldwide. There have been concerns over possible issues such as overvoltage and overcurrent. These PV systems are mostly connected at low voltage (LV). This paper presents a way to protect transformers from any harmful change in current, voltage, frequency and high temperature. The experimental system consists of a step-down transformer, current sensor, temperature sensor, and ARDUINO MEGA to monitor and control the system. The operating values are monitored using PC. The model of the system is simulated using MATLAB/PROTEUS. The performance of the system is investigated at normal conditions as well as at faulty conditions. The system succeeds to disconnect the loads to protect the transformer and displaying the values on real time.

Keywords: Distribution transformer; Protection relay, Arduino-based, PV system.