Protective relaying system for education

Abstract

A rapidly growing in power industry requires more reliable operation of power supply that increases complexity of power systems. For attaining this aim new communication solutions and an increased focus on protection may be needed. The power engineering department at IGEE has proposed advanced power systems initiatives to better prepare its students for the power industry field. One of these initiatives is the development of a new laboratory curriculum that uses digital relays to reinforce the fundamental concepts of power system protection. The simple relay protection lab planned at IGEE should include a test bench with distance, over-current and differential relays, and a relay tester that may be used for applying simulated waveforms to the relays. This project proposes a laboratory protection system fulfilling this task. It presents background on power system protection, modern relay technology, and relay testing, to support the design and practical setup of the protective relaying system. The report includes a theoretical part describing the components of power system protection, their function, and attributes in order to understand better the importance of power system protection. Three chapters covering the principles of protective relaying functions relevant to the lab are included. They cover the theory of overcurrent, differential and distance protection.Modeling and simulation can help students to better understand how a relay reacts during a fault or other non-fault disturbances. New design models of overcurrent and differential relay have been implemented in PC using power system simulator PSCAD. Proposals of lab assignments that can be performed in the protective relaying laboratory are presented at the end, using the designed models and the protective equipment available at the institute and donated for the purpose of this work.