Network partition-based hierarchical decentralised voltage control for distribution networks with distributed PV systems

Abstract The integration of large-scale distributed photovoltaics (PVs) in distribution networks (DNs) causes reverse power flow and the voltage violation problem. However, in some rural area, DNs do not have sufficient measuring information and communication ability to meet the challenge. In order to solve the voltage violation problem, this study proposes a voltage profile perception method and a voltage regulation analysis model as an alternative method to power flow calculations to guide the partition and voltage control of DNs. We then propose a novel hierarchical decentralised voltage control method strategy that combines cluster autonomous optimisation and cluster coordination optimisation in different time scales based on the DN partition. The optimal control is conducted for voltage regulation to minimise the amount of reactive power compensation and the active power curtailment under the DN operation constraints. The effectiveness and feasibility of the proposed method are demonstrated via simulation tests on a real 10.5 kV 34-node feeder in China.