FACTS Devices Allocation to Congestion Alleviation Incorporating Voltage Dependence of Loads

This paper presents a novel optimization based methodology to allocate flexibleac transmission systems (facts) devices in an attempt to improve the previouslymentioned researches in this field. static voltage stability enhancement, voltage profileimprovement, line congestion alleviation, and facts devices investment cost reduction,have been considered, simultaneously, as objective functions. therefore, multi-objectiveoptimization without simplification has been used in this paper to find a logical solution tothe allocation problem. the optimizations are carried out on the basis of location, size andtype of facts devices. thyristor controlled series compensator (tcsc) and static varcompensator (svc) are utilized to achieve the determined objectives. the problem isformulated according to sequential quadratic programming (sqp) problem in the firststage. this formulation is used to accurately evaluate static security margin with congestionalleviation constraint incorporating voltage dependence of loads in the presence of factsdevices and estimated annual load profile. the best trade-off between conflicting objectiveshas been obtained through genetic algorithm (ga) based fuzzy multi-objectiveoptimization approach, in the next stage. the ieee 14-bus test system is selected tovalidate the allocated devices for all load-voltage characteristics determined by theproposed approach.