Accelerated Dual Ascent Based Distributed Voltage Control for PV and BESS Coordination of Distribution Networks

The development of distributed photovoltaic (PV) power generation has been significantly promoted in recent years. With the increasing penetration of PVs, severe voltage violations may occur in distribution networks due to the intermittency and fluctuation of PV power output. Reactive power compensation by PV and active power charging/discharging by battery energy storage systems (BESS) are effective solutions. This paper proposes an accelerated dual ascent (ADA)-based distributed voltage control framework for PV and BESS coordination of distribution networks to alleviate the voltage violation. To maximise PV utilisation, the strategy prioritises PV reactive power control, while BESS active power rapidly responds to voltage deviations if the voltage exceeds predefined limits. The proposed voltage control strategy can effectively ensure distribution network security. Furthermore, to enhance the convergence speed of the traditional dual ascent (DA) algorithm, this paper incorporates an additional momentum term into the DA algorithm to obtain the ADA algorithm. To address the limitation of traditional voltage control, which requires iterative convergence before voltage control can be performed, an online voltage control strategy has been designed. The online implementation of ADA-based distributed voltage control leverages instantaneous voltage measurement to effectively handle rapid fluctuations of distribution networks. Moreover, the proposed method only requires information exchange between adjacent PVs and BESSs, thereby reducing the complexity of communication. Simulation based on an IEEE 123-bus distribution network and a typical rural distribution network demonstrated the proposed control strategy has a faster convergence speed and better voltage regulation effect.