Single phase consumers do not impose equal current flows in a three phase LV network like three phase consumers and current values are different at different times of a day. Consequently, they inject unbalanced current in the distribution network which may lead to unbalanced voltages more than the standard values. In this paper a novel and practical single phase DG system with control unit is introduced with control algorithm. The aim of this DG is voltage unbalance reduction. The control unit, selects the proper and optimal phase of LV system for DG connection repeatedly during all day long. The control system and DG unit are applied on a distributed network in Chahar Mahal and Bakhtiari substation (in Kohgiluyeh and Boyer Ahmad province of Iran) using DIgSILENT software and the results are presented.