A method for determining the introduction limit of distributed generation system in distribution system

This paper describes a new method for determining the introduction limit of DGS (distributed generation system) when DGS is introduced into distribution system of which the voltage is generally controlled by LCT (load-tap changing transformer) and LDC (line drop compensator). Nowadays, small scale DGS is being introduced into power distribution systems. But in that case, it is difficult to properly maintain the terminal voltage of low voltage customers within a permissible range. This paper reveals some correlations between the traditional voltage regulation method by LCT and LDC and the output of DGS, and also presents a method for determining the permissible introduction limit of DGS under proper voltage regulation of the power distribution system. This proposed method is applied to a 22.9 kV class power distribution system, and its validity is proofed through the simulation results.