Wave Aspect of Power System Transient Stability - Part II: Control Implications

This second part of a two-paper series gives an overview of key insights and control implications arising from the wave characteristics of power system transient stability. These insights, which are unique to traveling wave interpretation, are obtained through time-domain analysis of artificial and real test systems: "critical region for a stressed link near the end of a longitudinal system," "dispersed control in a path," "placement of controllers considering structure and load distribution in a system," and "localized transient stability enhancement." Good transient stability enhancement is successfully achieved by controllers in all test systems in terms of larger critical clearing time, which directly translates to increased maximum safe power transfer. The controller design is based on the transmission line analogy of traveling waves and load modulation effect. The concepts in this paper series can assist in improving the design of control strategies to enhance power system transient stability by considering the wave aspects.