الفهرس 
CHAPTER 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
A major development has taken place in the area of security operation research particularly in the optimization techniques. In the past, conventional techniques such as linear programming and quadratic programming were used to carry out the optimization process of the optimal power dispatch problems. Crisp constraints and objectives are modeled in such techniques. The progress of artificial intelligence techniques helps in solving the optimization problems.
In the electricity sector, AI techniques such as neural networks, genetic algorithms and fuzzy logic are being applied to different branches of power systems operation, planning, and control rather than traditional methods.
In this thesis, applications of one of these techniques (fuzzy logic technique) are presented. The uncertainty in power generation, power flow in transmission lines, and load demand lead to use the fuzzy logic phenomena. This thesis describes how to use fuzzy logic for building a number of power system operation applications (constrained optimal power dispatch–security regions- preventive control actions–corrective control actions).
The use of fuzzy logic leads to a revolution in the optimization power systems operation problems such as security and economic problems. Modeling of power system objectives and constraints using different membership functions are considered. Two shapes of membership degrees namely, triangular and trapezoidal are considered to determine the best power generation settings to remove the violations of the transmission lines power flows. Another aspect of security operation of power systems means finding the security region of operation for different generation units and for different conditions of critical situations of the transmission lines. The proposed security region is proposed with the reference of fuzzy rules for different positions of fuzzy constrained power dispatch controllers.
The emergency conditions such as forced outage of transmission lines, sudden increase in power demand and partial generation outages lead to more troubles in power system operation. For the active power dispatch, the violation in transmission lines is the significant effect of these troubles. So, planning for decreasing these effects of emergency conditions is important aspect for the operators. Preparing preventive and corrective control actions before emergency occurs lead to minimum change of control settings after emergency conditions. In this thesis, preventive and corrective control actions are prepared using fuzzy modeling of power system variables as well as the optimizations tools of the fuzzy linear programming technique. This thesis consists of seven chapters and two appendices. The thesis is based on 88 references. The chapters content can be summarize as:
In Chapter 1, a brief introduction is presented for the power system problems. These problems are economic dispatch, security assessments, emergencies analysis, and the appropriate control actions that removed the effects of emergencies such as preventive control actions.
In Chapter 2, the artificial intelligence techniques importance and their applications in the power systems operation concentrating on the fuzzy set theory applications are presented. In Chapter 3, a proposed optimal power dispatch (OPD) that handles fuzzy constraints as two membership models namely triangular and trapezoidal modes is presented. The optimization process is performed using the fuzzy linear programming (FLP) technique with fuzzy modeling of objective and constraints. The objectives of this chapter are satisfying the generation cost minimization and as well as keeping the power flows in transmission lines within their maximum permissible limits.
In Chapter 4, a proposed procedure is presented that depends on the multi-objective fuzzy linear programming (MFLP) technique to obtain the optimal preventive control actions, for power generation and transmission line flows, to overcome any emergency conditions. The proposed multi-objective functions are: minimizing the generation cost function, maximizing the generation reserve at certain generator, maximizing the generation reserve for all generation system and maximizing the preventive action for one or more critical transmission lines.
In Chapter 5, a proposed procedure is presented for solving the constrained power dispatch (CPD) as a mathematical programming problem taking into account the fuzzy models of system constraints. Multi-modes of optimal operation on the basis of security region for different positions of the CPD controller are presented. The linguistic rules for different controller positions are modified to model the system variables as constraints in the proposed approach.
In Chapter 6, corrective control actions are introduced for removing the effects of different emergency conditions, which may occur due to forced line outages, sudden increase in load demand and partial outage of generation stations.
In Chapter 7, the thesis conclusion and the future works that to be as extension of the thesis objectives are presented.