Stability Enhancement of an Industrial Power System by AVR Gain Readjustment

Excitation systems of synchronous generators contribute to effective voltage control and power system stability. Although the excitation system is tuned to enable the power system performs properly over a wide range of operating conditions, it may be necessary to retune it with the aim of improving the system stability during operating conditions not considered before. This paper shows how an unstable operating condition, of an oil refinery electric power system, after the occurrence of two simultaneous events may be avoided by simply adjusting the automatic voltage regulator gain in one of its synchronous generators.