REDUCTION OF TORSIONAL OSCILLATIONS IN LARGE TURBINE-GENERATOR SET USING THYRISTOR CONTROLLED BRAKING RESISTORS (TCBR)

Torsional vibrations and resonance problems with synchronous machines are most frequently encountered in rotor systems with long shafts and large inertias constituting a weakly damped mechanical resonator which exhibits a low resonance frequency. The subsynchronous resonance (SSR) phenomenon may occur when a steam turbine-generator is connected to a long transmission line with series compensation. The main purpose of this paper is to verify the capability of the Thyiristor Controlled Braking Resistor (TCBR) to reduce the electromechanical oscillations that occur when a steam turbine generator (T-G) is connected to a long transmission line with series compensation. This investigation was done based on the IEEE Second Benchmark Model.