Optimal placement of Static VAR Compensators in distribution feeders for load balancing by genetic, algorithm

Unbalanced load is one of the fashionable problems in distribution systems, which has great unfavorable effects such as unbalancing in three phase voltages, increase of energy losses and occupation of feeder capacity. There are two main sources of unbalanced load, the first ununifored distribution of the single phase customers and the other, their accidental and unsimultaneous treatment. For reform load unbalancing particularly ununiforedness of customers used traditional methods of customer replacement. But nowadays there is a novel method that we can balance the load by the reactive power compensation. Unbalanced load in distribution feeders has two main features, 1) unbalancing rate is variable according to the time, 2) it would be dispersion among the feeder. We can use Static VAR Compensator (SVC´s) and so they will be able to reform this unbalancing according the specific period of time variation. Therefore if we want to reform the load unbalancing, according to its dispersion characteristic, we can use some SVC´s among the feeder. In this paper used an optimal method based on genetic algorithm for SVC´s placement among the feeder for load balancing during a specific period of time. In addition with this method a novel algorithm has been used which make a hierarchy of the priorities in considering the buses. At last, the unbalance treatment of some real samples of the feeders were studied by using prepared software which have been done during a week and effect of SVC´s application have been simulated too. The results of simulation studies show that by using optimally the SVC´s in distribution feeders we can balance the load current and we are able to decrease considerably unfavorable effects. Financial analysis shows that this method is optimum from economical point of view.