6479

6479

جايابي TCSCدر سيستمهاي قدرت از طريق بهينه سازي چند منظوره ارتقاء يافته با الگوريتم هاي هوشمند

دكتري

برق

خرداد 1388

خرداد 1388

دكتر محسن كلانتر

ABSTRACT These days, high efficiency, maximum reliability, and security in the design and operation of power systems are more important than ever before. The difficulties in constructing new transmission lines due to limits in rights for their paths make it necessary to utilize the maximum capacity of existing transmission lines. Flexible alternating current transmission system (FACTS) devices, as modern active and reactive power compensators, can be considered as viable and feasible options for satisfying the voltage security constraints in power systems, since their response to perturbations in urgent circumstances is fast and their performance in normal conditions is flexible. This investigation attempts to determine the optimum amounts, types, numbers and locations of thyristor controlled series compensators (TCSCs) and static var compensators (SVCs) based on a multi-objective function. This is done by considering static voltage stability enhancement, power loss reduction, and voltage profile improvement as the allocation objectives; FACTS devices investment cost reduction considers interest rates simultaneously. Therefore, non-linear multi-objective optimization has been used in this thesis in an attempt to find a logical and accurate solution to the allocation problem. Despite previous works, and for approaching a practical solution, an estimated annual load profile has been considered for calculating power losses and voltage violation. Here, an approach based on the goal attainment and fuzzy methods, combined with a genetic algorithm and simulated annealing is used to compromise between contradictory objectives. This approach prevents the optimization to be trapped in local optimums. According to the obtained results on both the IEEE 14-Bus and Fars Regional Electric networks, the implemented method results in the satisfaction of such allocation objectives as power loss reduction, investment cost reduction, security margin improvement, and voltage violation alleviation, simultaneously. It is also concluded that the entire investment of the FACTS devices is paid off and some additional savings is made. Besides, the optimization procedure in this study has reached the global optimum- solution by passing a zigzag convergence path and not trapped in a local minimum. Results show that ignoring different load levels in allocation procedure for a practical power system may even lead to a wrong planning decision about the optimum structure of these devices. Keywords: Allocation, Multi-objective Optimization, Heuristic Algorithms, TCSC, SVC.