The Nature Of The Power System Stability Surface

Abstract

An increasing pressure on power system operators to operate their system closer to stability limits, together with continual advances in affordable computing power has motivated research into tools capable of automatically optimising ower system stability and economy. In .,!er to design any o timisation strategy it is essential to posses a thorough ungrstanding of the nature of the optimisation surface. In this light, this paper describes research, based upon an exhaustive analysis of the stability terrain of a small power system, which provides an essential insight into the system wide nature of power system stability. The paper demonstrates that even a small power system exhibits characteristics such as non-linearities and discontinuities, and includes many stability local minima, all of which are important considerations in the selection of suitable optimisation algorithms. The paper argues that, having demonstrated certain characteristics for a small power system, their are no logical reasons why the same characteristics should not be expected in larger and more complex systems, and thus strongly recommends that any algorithms for ower s stem stability optimisation should be accordingly gsignedl