This paper presents the application of anAutomatic Phase Balancing Device (APBD) to reduce current unbalance in low voltage distribution networks. The proposed algorithm allowsus to calculate the unbalanced level and to conduct the automatic phase balancing device during load variations. This device was then applied to a low voltage feeder of Cau Giay district (Viet Nam). Results show that the unbalanced current is always maintained lessthan 15 %. | Journal of Science and Technology 55 (1) (2017) 108-119 DOI: CURRENT UNBALANCE REDUCTION IN LOW VOLTAGE DISTRIBUTION NETWORKS USINGAUTOMATIC PHASE BALANCING DEVICE Tran Thanh Son*, Tran Anh Tung Electrical Engineering Faculty, Electric Power University, 235 Hoang Quoc Viet, Ha Noi * Email: sontt@ Received: 15 May 2016; Accepted for publication: 12 October 2016 ABSTRACT This paper presents the application of anAutomatic Phase Balancing Device (APBD) to reduce current unbalance in low voltage distribution networks. The proposed algorithm allowsus to calculate the unbalanced level and to conduct the automatic phase balancing device during load variations. This device was then applied to a low voltage feeder of Cau Giay district (Viet Nam). Results show that the unbalanced current is always maintained lessthan 15 %. Keywords: automatic phase balancing device, unbalanced current, energy loss, PLC, load curve, power quality, low voltage distribution networks. 1. INTRODUCTION During the generation, transmission, distribution and consummation of electric energy, power company and customers are very interested in power quality and reliability. Power quality is defined by the quality of frequency and voltage. The frequency is almost regulated at power plants. Meanwhile, voltage quality regulation is the main function of distribution grids because they directly supply loads. Voltage quality is represented by a set of index such as voltage deviation, voltage sag, interruption, transient overvoltage, harmonics and voltage unbalance. In this paper, the voltage unbalance is studied. There are many sources that can cause unbalance in distribution grids. One of these sources is load unbalance or current unbalance. In low distribution networks, due to major single-phase loads, this index may be not guaranteed. Moreover, energy loss of distribution grids is also an important index, in particular in Vietnam. One of main sources of power loss .
