Tuning synchronous generator voltage regulators using on-line generator models

Automatic Voltage Regulator tuning for voltage control of power system generators has in most cases been done for the "open-circuit" condition of the synchronous generator. The basic machine equations and actual measurements on the generator indicate that the AVR operates in an entirely different control environment when the generator is connected on-line and operating at rated load conditions. This paper describes a technique for tuning an AVR for on-line conditions and makes a comparison between terminal voltage transients for on-line tuning and open-circuit tuning for a specific application. The system studied was a generator installation of the Calgary Power system in Canada where a static AVR is being installed on a recent addition to the generation at a plant in their system. It was found that for this particular application there was a definite improvement in terminal voltage damping when the AVR was tuned for on-line conditions rather than for open-circuit conditions. It was also found that tuning the AVR for on-line conditions provided additional damping to electric power transients at the plant.