الفهرس 
Flexible AC Transmission Systems (FACTS) ControlOnly 14 pages are availabe for public view
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Abstract
Power systems need to be continuously expanded and upgraded to cater the ever growing power demand. In recent years, power system planners have faced numerous
difficulties in adding new power stations and building new transmission lines. In
view of new generating stations, superconducting generators (SCGs) are expected to
be a good choice among AC generators due to many advantages of SCGs over
conventional machines. Also, the technology of flexible AC transmission systems
(FACTS) is considered a good solution for the problem of constructing more new
lines. The objective of this study is to design and implement reliable controllers for
SCG and for STATCOM included in a multi-machine power system.
To validate the effectiveness of the proposed SCG and the controlled
STATCOM: firstly, a single machine-infinite bus (SMIB) power system is
considered and the eigenvalues analysis is used to evaluate the small signal
dynamics. However, the transient response is studied using nonlinear time
simulations represented by SIMULINK model when the system is subjected to
various types of disturbances under different operating conditions using different
control systems. The simulation results illustrate the system performance
improvements achieved using the proposed controller compared with the
conventional techniques.
Secondly, the study is extended to evaluate the effectiveness of the proposed
control scheme on the performance of multi-machine power systems. A 39-bus power
system network includes a SCG plus nine conventional generating units of different
types and ratings is considered. To represent the studied power system, the nonlinear
mathematical model is established to achieve a satisfactory degree of accuracy and to
study the system performance under various types of contingencies. In view of
generators control, the conventional units are equipped with proper AVRs and PSSs
in their excitation loop and the SCG is controlled using PID controller in the
governor loop. The system complexity makes the design of FACTS controllers is formulated as an optimization problem. The MATLAB optimization toolbox is
employed to search for optimal controllers parameters.
Finally, a controller parameters varying strategy is proposed using ANN
according to the transmission line loading condition for better damping effect. This
approach is successfully applied to design the damping controller for STATCOM as
the simulation results demonstrate good damping effects of these controllers.
It has been shown that, the power system performance is affected by
interactions of the FACTS devices with different control systems. The simulation
results demonstrate the capability of the STATCOM to control the bus voltage as
well as system performance enhancement.s