Abstract
In order to prevent the troubles of electrical facilities, it is very important to adequately keep the power quality in distribution system. The imbalances of voltage and current are one of power quality, and many troubles caused by the imbalance of voltage are reported. In order to improve the imbalance of voltage, it has been recommended by guideline that the imbalance rate of facilities is kept below 30% by high voltage (HV) consumers. However, the actual condition of the imbalance of load in HV consumers has not been clarified. In the paper, it was clarified by measurement that the imbalance rate of load is over 30% in many HV consumers. On the other hand, it has been recently reported that the static capacitor (SC) in HV consumer influences the power quality, such as voltage and harmonics. From this background, the influence of SC to the imbalance of voltage and current was investigated. Two methods for improving power factor by using SC are discussed by simulation by using the equivalent model of distribution system.
