Main Article Content
Abstract
This work develops a Digital Relay for the protection of Generator Transformer in Mettur Thermal Power Plant. The Digital Relay, also called a numerical relay,refer to protective relay uses an advanced microcontroller to analyse power system voltages and currents for the purpose of detecting the faults in an electric power system. The main objective of this work is to give Digital Relay protection for Generator Transformer against over current of three phases, negative sequence (or) unbalanced currents of three phases and earth fault current.
The present system with Electromagnetic Relay, existing there makes use of individual relays and monitoring equipments for identification and isolation of each fault. Thus the monitoring and control of the faults becomes very difficult and apart it is costlier as it involves lot of relays and control equipment’s. In addition the accurate values of monitored parameters cannot be obtained in these types of relays. These electromagnetic relays are replaced with a digital relay to give various advantages which includes advanced programmable functionality providing high performance level, flexibility as well as additional monitoring capabilities and they are able to communicate with other digital equipment while these functions are not quite possible in Electromagnetic relays.