الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Modern electric power systems have grown complexity large to cover the rapid rate of increase of load demands. Heavier loading of the generating facilities combined with the large size of the high-voltage interconnected lines, tend to decrease the system stability margin. Moreover, system wide stability requires very fast acting and efficient coordinated power system stabilizers to be installed within generating power plants. Recently, however, due to advances in computer technology and to the refinement of optimal control theory it has become practical to apply linear optimal control methods to power system stability problems. Linear optimal state feedback is very efficient in stabilizing the poor system during contingencies resulting from small disturbance signals. But due to the lack of measuring all states, we trend to stabilize the power system by output feedback controllers instead of using state reconstruction via optimal Kalman filter or dynamical state observer. However, controlling geographically separated multi-machine power plants requires longer time for exchange information and computations. This may endanger system wide stability following a major disturbance. To overcome this, it is recommended to design decentralized control scheme composed of local controllers.
This thesis introduces a MATLAB/SIMULINK approach for the design and analysis of the output feedback centralized (and decentralized) controllers used in power system stabilization. A comprehensive analytical study for the available output feedback control techniques used in small signal stability problem of power systems has been conducted. The available techniques are generally based on linearized models of multi-machine power system, due to the lack of mathematical tools to deal conveniently with the non-linearity associated with large oscillations, most of the optimization studies have been restricted to synthesizing a linearized system based controller to damp small oscillations. However the optimal control derived from linear control theory is not always adequate to optimize system performance following a large disturbance, when appl9ed to nonlinear system model. A realizable SIMULINK nonlinear model of one machine connected to an infinite-bus system has been constructed to verify the validity of the designed output feedback control laws.