Enhancement of power system transmission using robust control design

Power systems have been required to operate close to stability limits for extensive periods of time. Controls like power system stabilizers, exciters, governors and special HVDC controls ensure that the system is able to operate, without instability, under a wide range of operating conditions. Hence their robustness becomes an important issue. This paper discusses a methodology that is used to analyze the stability robustness of controls in a power system and also presents a novel method to design robust controllers. Numerical results for sample test systems are presented along with those obtained from conventional techniques