Voltage Control Strategy for Low-Voltage Distribution Network with Distributed Energy Storage Participating in Regulation under Low-Carbon Background

Abstract

With the gradual advancement towards the goal of carbon neutrality, photovoltaic power generation, as a relatively mature zero-carbon power technology, will be connected to the grid in an increasing proportion. A voltage control strategy, involving distributed energy storage, is proposed in order to solve the voltage deviation problem caused by the high proportion of PV connected to the low voltage distribution network (LVDN). A voltage calculation method of the LVDN node with a high proportion of PV is proposed. According to the voltage distribution of the LVDN nodes running throughout the day, fuzzy cluster analysis was used to partition the nodes in the LVDN. A two-objective mathematical model for optimizing distributed energy storage in a partition was constructed, and a particle swarm optimization algorithm was used to solve the model. A voltage control strategy based on sensitivity analysis is proposed, and a mathematical model is established to analyze the relationship between the node current increment and the node off-limit voltage. The mathematical relationship among the node off-limit voltage, node off-limit power and energy storage exchange power is derived, and the voltage deviation of the distribution network can be suppressed by adjusting the injected power of the distributed energy storage. Through case analysis, it is verified that the proposed voltage control strategy can reduce the voltage deviation of the distribution network nodes, effectively solve the problem of the distribution network voltage deviation, and reduce the active power loss.