Effective placement of dynamic control devices in large-scale power systems

Dynamic voltage support and reactive power compensation have been long recognized as a very significant measure to improve the performance of electric power systems. The rapid advances in the power electronics area have made it both practical and economical to design and install powerful dynamic control devices such as power system stabilizers (PSSs) and static var compensators (SVCs). With numerous potential PSS and SVC devices to be installed across the system, the task of their most effective placement can be a very complex one. This paper presents a new computer-aided methodology for effective placement of various PSSs and SVCs in large-scale power systems using numerically-calculated dynamic mode sensitivities and fast search algorithms. The new methodology comprises a two-stage algorithm. In the first stage, candidate locations for SVC devices across the system are determined via approximate, but very fast, static reactor placement analysis. In the second stage, the composite effect of various combinations of SVC and PSS controls on the dynamic system performance is determined using first-order dynamic mode sensitivities, The paper also describes a recently completed major study on the Saudi power grid (SCECO) in which the new techniques were successfully used to improve system dynamic performance via carefully placed PSS and SVC devices.