Analysis on voltage deviation inactive distribution network and active voltage management

Large scale of distributed generation (DG) in distribution network results in potential power quality problems, such as voltage deviation, fluctuation and flick, or harmonics. This paper starts from analysis of voltage deviation for DGs. System short circuit capacity, R/X ratio, DG capacity and power factor are investigated to have main impacts on voltage deviation level. A case study model is developed using DigSilent. Penetration ratio (PR), distribution (DT) and dispersion (DP) level are defined to describe DG connection status. Simulation is conducted to explore the voltage deviation rules in distribution network with high penetration level of DGs. The maximum capacity for distribution network to accommodate DG is estimated under limitation of voltage deviation level by power quality standard. According to active distribution network principles, some guidelines for active voltage management are presented.