Design and Construction of the Standard Inverse and Constant Time Overcurrent Relay Simulator Based on Arduino

Abstract : Overcurrent relay as one of the protection systems in the electricity distribution network has been improved in performance through the implementation of microcontrollers. To simulate the work of overcurrent relays, an Arduino module based on Atmega328P can be used to study the working algorithm of overcurrent relays. This research aims to design and build an Arduino-based overcurrent relay simulator with two working time characteristics, namely standard inverse and constant time. The simulator is equipped with a CT-based current sensor and a PZEM-004T module to read the current, as well as using a 20×4 I2C LCD and a 4×4 Keypad as the user interface. Once the simulator is designed, the next step is testing to measure the accuracy of the sensor readings and the performance of the relay at various variations of current and timing settings. The test is performed at a voltage of 220 Volt Alternating Current (AC) and at a variety of current variations i.e., 0.5 A, 1 A and 1.5 A currents. The test results showed that the system was able to work according to the characteristics of standard inverse and constant time with an average error of measurement of the relay working time of less than 2% for standard inverse and 0% for constant time. This proves that this Arduino-based overcurrent protection system is accurate and responsive.