الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The small-signal stability investigations usually involve the analysis of the linearized system governing equations that define the power system dynamics. Whereas, transient stability of the power system deals with system analysis; following a severe disturbance, Such as a single or multi-phase short-circuit or a generator loss. Under these conditions, the linearized power system model does not remain valid. So the control objective is to enhance the stability and to improve the dynamic response of a single machine infinite bus (SMIB) system, under different operating conditions. The Proportional, Integral and Derivative (PID) controller involves three parameters, denoted P, I, and D. these values can be interpreted in terms of time: P depends on the present error, I on the accumulation of past errors and D is a prediction of future errors. The PID controller is used to improve the dynamic performance of a synchronous machine under a wide range of operating conditions. The conventional power system stabilizer (PSS) which uses lead-lag compensation, where gain settings designed for specific operating conditions, it presents poor performance under different conditions. Therefore, it is so difficult to design a stabilizer that could present good performance in all operating points of electric power systems. In an attempt to cover a wide range of operating conditions, Fuzzy logic control has been suggested as a possible solution to overcome this problem, thereby using linguist information and avoiding a complex system mathematical model, while giving good performance under different operating conditions. In this thesis, a systematic approach for fuzzy logic control design is proposed. The study of fuzzy logic power system stabilizer for stability enhancement of a single machine infinite bus system is presented. In order to accomplish the stability enhancement, speed deviation and acceleration of the rotor synchronous generator are taken as the inputs to the fuzzy logic controller. These variables affect the damping of the generator shaft mechanical oscillations. The stabilizing signals were computed using the fuzzy membership function depending on these variables.
A comparison of PID, PSS and Fuzzy controllers are presented through small signal stability of power system comprising of one machine connected to infinite bus. The power system components such as synchronous machine, exciter, PID, PSS and Fuzzy are also modeled after linearization of governing equations.