Control of the phenomenon of subsynchronous resonance

A solution to the phenomenon of subsynchronous resonance has been designed and a full-scale on-site system will be in commercial service in January 1976. This is extremely important to the continued use of series-compensated transmission circuits which offer important economic advantages to the industry for long-haul transmission. Field tests have confirmed the calculations of the pertinent turbine-generator characteristics, particularly the torsional natural frequencies, damping coefficients, and the alternating torque levels that the shafts will experience for various armature stimuli.