Journal of Image Processing and Intelligent Remote Sensing ISSN 2815-0953 Vol: 02, No. 02, Feb-Mar 2022 http://journal.hmjournals.com/index.php/JIPIRS Copyright © The Author(s) 2022.This is an Open Access Article distributed under the CC BY license. (http://creativecommons.org/licenses/by/4.0/) 39 Superior Short circuit & Overcurrent Protection of Devices like Alternator, Transformer etc. Md. Tabil Ahammed 1 , Shadat Hossain 2 , Md. Mehedi Hasan 3 , Golam Rabby 4 , Nazmul Huda 5 1,2,3,4,5 Department of EEE, Bangladesh University of Business and Technology 1 ahtabil53@gmail.com Abstract: Improved motor, controller and branch circuit protection has been the subject of a never-ending stream of magazine articles, IEEE papers and amendments to the National Electrical Code. Combining motor short-circuit protectors and properly certified motor controllers may provide superior branch circuit overcurrent protection. An Alternator, Transformer, and Other Devices with Superior Short Circuit and Overcurrent Protection are discussed in this study. Keywords: short-circuit protectors, overcurrent Alternator, Transformer. 1. INTRODUCTION: When the phasor difference between two or more electrical values reaches a predefined amount, a differential relay is activated. Protective relaying with differential selection and action is the most effective. Phase angle and magnitudes of two or more electrical values are compared to see whether they are comparable. Comparing two electrical values in a circuit using differential relays is an easy and effective method. Generators, transformers, bus bars, transmission lines, and other components make up the contemporary electric power system. Protection against a range of fault circumstances, which may occur sooner or later, is both desired and required. It is convenient for us to focus on protecting alternators, transformers and bus bars as well as protecting against excessive voltages. Alternator stator winding defects are the most critical and need quick care. Short circuits in the transformer or in the connections to the transformer are the most common causes of transformer failures. To defend against these failures, a differential relay scheme is utilized since the differential nature of measurements makes this system more sensitive than conventional protection methods. The differential protection relay is a kind of relay whose functioning is dependent on the phase difference between two or more electrical values. An electrical quantity's phase angle and magnitude are compared to determine its phase angle. For instance: Consider the comparison of the transmission line's input and output currents. If the transmission line's input current is greater than its output current, then extra current is flowing through it as a result of the defect. The differential protection relay may be operated by the current difference.