Inter line power flow controller is a new concept for the compensation and effective power flow management of multi-line transmission systems. The IPFC employs a number of Voltage Sourced Converters (VSCs) linked at the same DC terminal, each of which can provide series compensation for the selected line of the transmission system. Through common dc link, any inverters within the IPFC is able to transfer real power to any other and thereby facilitate real power transfer among the line. In this work the IPFC system used for compensation of voltage sag in two identical lines like 11kv and 10kv systems. The prototype IPFC system was developed and verified with hardware results. When the voltage sag is compensated, reactive power is controlled and transmission line efficiency is improved.

Key words - FACTS, SSSC, IPFC, Series Compensation, Power converters.