Analysis of voltage regulation problem for a 25 kV distribution network with distributed generation

This paper introduces a distribution network benchmark for investigation of alternative distribution system planning approaches. The benchmark system is part of a 25-kV distribution network serviced by a Canadian utility company and includes a significant amount of distributed generation (DG) sources. The benchmark is used to study under-voltage problems experienced by the utility company which are associated with interaction between DG units and the conventional voltage regulation apparatus. Analytical models of the network and line voltage regulators are developed. Control modes of the voltage regulators and performance during reverse power flow conditions are also discussed. Alternative planning approaches to mitigate the reported problems are introduced and their effect on voltage profiles and power flows are investigated