Research On Static Security Region In Power System

Security region is more and more widely used in power system stability control and loadability margin prediction. In order to assess and control the security region more accurately, it is necessary to get a full knowledge of the nature of the security region boundary. This paper mainly studied the nature and topology of the static security region boundary in the load parameter space, which is comprised of static voltage stability limits, small signal stability limits and generation active power limits. From the observation of static security region at various contingencies, a nonconvex structure of the security region is observed. The influences of excitation parameters, PSS parameters, inertia constant and load characteristics on the security region boundary are then discussed, and the simulation results initially revealed the causes of the nonconvex phenomenon and its changing mechanism with system parameters. The work of this paper is helpful to the further research on static security region, and has great significance to the operation of power systems.