Voltage stability improvement of distribution networks using reactive power capability of electric vehicle charging stations

Abstract

Modern power networks are affected by the increasing adoption of electric vehicles (EVs) driven by environmental concerns. Electric vehicle charging stations (EVCSs) pose serious challenges due to the fluctuating charging demand leading to voltage instabilities and affecting the secure operation of power networks. This research proposes a novel approach to address these instabilities by utilizing the capabilities of EVCSs in absorbing and injecting reactive power. An efficient management of the reactive power of EVCSs is achieved by embedding differential evolutionary algorithms in a specialized optimization framework. We employ the two-point estimation method (2PEM) to deal with the uncertainties in renewable energy, load fluctuations, and EV demand patterns. The effectiveness of 2PEM is validated through comparison with Monte Carlo simulation (MCS). Demonstrated on a 51-bus network model, the proposed framework represents its real-world applicability. The results show a significant improvement in voltage stability, along with a considerable reduction in power loss.