Interline Power Flow Controller (IPFC) Deployment in Long Transmission Lines and its Effects on Distance Relay

This article presents apparent impedance calculations of the existing transmission lines and their distance protection zone 1, zone 2, and zone 3 settings when the interline power flow controller is deployed on the existing transmission lines. An interline power flow controller (IPFC) can considerably affect the performance of a distance relay in an existing transmission line. Installation of IPFC into an existing transmission line near generating plants is challenging in terms of installation of the IPFC in an available place and changing existing protection setting requirements of a transmission line. Due to the deployment of the IPFC into the transmission line, there will be a change in transmission line apparent impedance that will affect the zone settings of the distance relay. These zone settings play a major role in the protection of transmission lines. The application of IPFC is to control power flows of multiple transmission lines with different loading conditions. Distance protection setting calculations are performed on 2X660MW Singhitarai power plant (Chhattisgarh, India) 400 kV outgoing lines with the existing MICOM P443 distance relay with and without deployment of the IPFC. Zone settings for the line to ground (L–G) fault and three-phase faults are analyzed and the results are presented. © 2021, The Institution of Engineers (India).