Novel Control Design for Simultaneous Damping of Inter-Area and Forced Oscillation

Abstract

Forced oscillation (FO) has recently been detected in power grids, e.g., Nordic and Western American power systems. It has been reported that the FO is excited by forced disturbances, which consist of the frequencies nearly equal to inter-area oscillation frequencies. The FO can lead to severe resonance even for the system with an inter-area damping margin higher than the industry standards. These major events and concerns lead to intensive research of the FO. Though numerous techniques have successfully been applied for FO detection, only a small number of research works have focused on the damping of the FO. Lack of proper control for the FO may lead to instability. Hence, in this paper, a power oscillation damper (POD) is proposed to damp both the FO and inter-area modes simultaneously. The adaptive control technique is applied to enhance the FO mode along with a moving window time, which also avoids the new installation of PODs. Besides, the event-triggered control strategy is used to activate the functions of the new adaptive POD appropriately. The controller s performance and robustness are verified in the modified 14-machine Southeast Australian (SE-A) power system under various uncertainties and disturbances.