Paper Title
Sub-Synchronous Resonance Alleviation in Power System using Facts Devices
Abstract
Flexible AC transmission systems (FACTS) have been extensively used in recent past for solving various power
system steady state control problems. Additionally, series compensation of transmission lines is being done using capacitor
banks so that overall power transfer capacity can be improved to ensure stable operation. However, this gives rise to subsynchronous
resonance (SSR) phenomenon under which there may be exchange of energy between mechanical and electrical
system at frequencies below the synchronous value, damaging the axis system of generator. This paper investigates the effect
of FACTS devices like Static Synchronous Compensator (STATCOM) and Unified Power Flow Controller (UPFC) for
alleviation of SSR in a single machine infinite bus system. Simulation studies have been carried out (i) with no FACTS
device and (ii) with FACTS device. These studies have shown that SSR in the system can be alleviated to a great extent by
using STATCOM. With UPFC the system oscillations are damped out i.e. mitigation of SSR achieved and by equipping
fuzzy logic controller better results have been obtained.
Keywords: FACTS, Fuzzy logic control, STATCOM, Sub synchronous Resonance (SSR), Torsional Interaction, Unified
Power Flow Controller (UPFC).