Performance evaluation of energy-shaping approach controllers for synchronous generators using a finite-element model

Usually, power system stabilizer (PSS) design is usually made using low-order two-axis models. Remarkable robust characteristics and systematic construction can be obtained with the recent developments on energy-shaping approaches to the design of excitation control. However, the properties and performance of the resulting control designs are also evaluated using low-order equivalent-circuit models because large (i.e. industrial scale) synchronous machines are not readily available to designers and researches. This may lead to doubts about the controller behaviour under true operating conditions. The aim of this paper is to develop a finite-element model, derived from fundamental Maxwell equations, to simulate the dynamics of synchronous generators. Subsequently, the finite-element model is used to show that energy-shaping control designs, obtained with low-order models, keep their performance characteristics when applied to the actual machine. In this way, in order to circumvent the lack of the real machine, a very detailed finite-element model is developed to represent turbine generators connected to large power systems. The numerical model incorporates simulation of rotor motion, iron magnetic nonlinearity and eddy currents in the solid rotors of turbine generators. Copyright (C) 2004 John Wiley Sons, Ltd.