الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
It is a great importance to keep the voltage profile at a power system buses within prescribed tolerance of ± 10 % . keeping an acceptable voltage profile at the system buses is a challenging and a system-wide task. The reactive power flow in the lines of a power system dicates the voltage profile at the system buses.Voltage-control is rooted in rescheduling of this flow of reactive power. Despite the fact that many voltage-control techniques are available to electric power system operators, these systems around the world have been subjected to voltage instability problems and voltage collapses that causes in many accoaions complete system breakdowns.
Static VAR compensator SVC is one of the shunt connected FACTS devices which are used in power system primarily for the purpose of voltage and reactive power control. In this thesis, a fuzzy logic based supplementary controller for static VAR compensator SVC is developed which is used for varying firing angle of SVC in order to achieve better, smooth and adaptive control of reactive power in transmission systems. As well as processing alarms related to voltage stsbility. The fuzzy controller monitors system voltages and system VAR resources and generates appropriate control signals to each VAR source in the system to maintain acceptable system voltage levels. The fuzzy alarm processor generates an individual alarm for each voltage region, and a general alarm signal that indicates the overall system condition. The controller/processor that has been completely designed, programmed, and tested for a four-generator test system. It has been interfaced with power system simulation software to test its performance under on-line conditions.