Yamini Arora Int. Journal of Engineering Research and Applications www.ijera.com ISSN : 2248-9622, Vol. 4, Issue 9( Version 2), September 2014, pp.59-64 www.ijera.com 59 | Page Voltage Profile Improvement of distribution system Using Particle Swarm Optimization Yamini Arora PG Scholar, Department of Electrical Engineering, JEC, Jabalpur Abstract: Distributed generations (DGs) play an important role in distribution networks. Distributed generation (DG) exists in distribution systems and is installed by either the utility or the customers. Distributed Generators (DGs) are now commonly used in distribution systems to reduce the power disruption in the power system network. Due to the installation of DGs in the system, the total power loss can be reduced and voltage profile of the buses can be improved due to this power quality of the distribution system is improved. Studies show that non-optimal locations and non-optimal sizes of DG units may lead to losses increase, together with bad effect on voltage profile. So, this paper aims at determining optimal DG allocation and sizing. To do so, the optimization technique named Particle Swarm Optimization (PSO) is used .this Particle Swarm Optimization (PSO) approach), capable to establish the optimal DG allocation and sizing on a distribution network. This paper presents optimal placement and estimation of distributed generation (DG) capacity using Particle Swarm Optimization (PSO) approach in the distribution systems to reduce the real power losses and to gain voltage profile improvement. The proposed (PSO) based approach is tested on an IEEE 30-bus test system. Keywords—DG, PSO, Power Loss, Voltage Profile I. Introduction Distributed generation is any electricity generating technology installed by a customer or independent electricity producer that is connected at the distribution system level of the electric grid [1]. With the increasing expanding of network construction in the modern power system and the rapid development of renewable energy resource, distributed generation (DG) has become an important form of electrical source. More and more DGs are connected into the power distribution system. It is predicted that DG would have a share of about 20% of new generating units being on lined [2]. DG effects in distribution network depend on several factors such as the DG place, technology issues, capacity and the way it operates in the network. DG can significantly increase reliability, reduce losses and save energy while is cost effective, though it suffers from some disadvantages because of the isolated power quality functioning, and voltage control problems. Generally, planners assess DG functioning in two respects: costs and benefits. Cost is one of the most important factors that should be considered regarding DG application[3]. So, to reach to these targets, loss reduction and voltage profile improvement of the electric system with the presence of DG requires the definition of several factors such as, the best technology to be used, the number and the capacity of the units, the best location, the type of network connection and etc. The problem of DG allocation and sizing is of great importance. The installation of DG units at non-optimal places and with non-optimal sizing can result in an increase in system losses, damaging voltage state, voltage flicker, protection, harmonic, stability and implying in an increase in costs and, therefore, having an effect opposite to the desired [4,5]. Several optimization techniques have been applied to DG placement and sizing, such as genetic algorithm [6], tabu search [7], heuristic algorithms [8,9] and analytical based methods [10], analytical method to place DG in radial as well as meshed systems to minimize power loss. However, this method only optimizes location and considers size of DG as fixed. In this paper, Particle Swarm Optimization algorithm (PSO) is presented as the optimization technique for the allocation and sizing of DG in distribution networks in order to loss reduction in distribution network with minimum economic cost test system. The 30 bus test feeder is selected to test proposed method [11].A lot of technologies are used for DG sources such as photo voltaic cells, wind generation, combustion engines, fuel cells etc.[12][13]. Usually, DGs are attached with the already existing distribution system and lot of studies is performed to find out the best location and size of DGs to produce highest benefits. The different characteristics that are considered to identify an optimal DG location and size are the minimization of transmission loss, maximization of supply reliability, RESEARCH ARTICLE OPEN ACCESS