A review of voltage and reactive power control algorithms in medium voltage distribution networks

Abstract

Current power network was built in mind that there will be mostly one-way power transmission, but as there is increasing penetration of distributed generation (DG), power network evolves and changes. Thereof old control strategies and algorithms used in power distribution do not fully utilize ever evolving power network in ensuring minimum active power loses, best distribution power generation for optimal voltage and frequency control. The main objective of this paper is review and comparison of heuristic algorithms in medium-voltage (MV) distribution networks with high distributed generation (DG) penetration. The specific goal is integrating reviewed algorithms in distributer power network control to minimise power loss, control active and reactive power flow between transmission and distribution power networks and utilization of current power network structure with growing number distributed generation penetration and thus minimizing required cost for its upgrade. Due to complexity of different power network structures and control methods used in managing it, algorithms are reviewed used in ensuring fast and reliable calculations by guaranteeing as minimum active power loss as possible and by improving power system performance over existing centralised as well as decentralised control methods. For both control methods distributed generators requires to be endowed with communication capabilities, as it is effective in driving the voltages within the admissible intervals and, additionally, it exploits the cooperation among the distributed generators and controllers to reach power network objectives of minimal power loss, voltage stability as mentioned before.