Incorporating Charging/Discharging Strategy of Electric Vehicles into Security-Constrained Optimal Power Flow to Support High Renewable Penetration

Abstract

Abstract:This research aims to improve the operational efficiency and security of electric power systems at high renewable penetration by exploiting the envisioned controllability or flexibility of electric vehicles (EVs); EVs interact with the grid through grid-to-vehicle (G2V) and vehicle-to-grid (V2G) services to ensure reliable and cost-effective grid operation. This research provides a computational framework for this decision-making process. Charging and discharging strategies of EV aggregators are incorporated into a security-constrained optimal power flow (SCOPF) problem such that overall energy cost is minimized and operation within acceptable reliability criteria is ensured. Particularly, this SCOPF problem has been formulated for Jeju Island in South Korea, in order to lower carbon emissions toward a zero-carbon island by, for example, integrating large-scale renewable energy and EVs. On top of conventional constraints on the generators and line flows, a unique constraint on the system inertia constant, interpreted as the minimum synchronous generation, is considered to ensure grid security at high renewable penetration. The available energy constraint of the participating EV associated with the state-of-charge (SOC) of the battery and market price-responsive behavior of the EV aggregators are also explored. Case studies for the Jeju electric power system in 2030 under various operational scenarios demonstrate the effectiveness of the proposed method and improved operational flexibility via controllable EVs.

Predicting Charging Time of Battery Electric Vehicles Based on Regression and Time-Series Methods: A Case Study of Beijing

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An Expeditious Methodology to Assess the Effects of Intermittent Generation on Power Systems

“…The uncertainties of wind and solar energy sources have been widely explored in OPFs, whether these were coordinated with conventional generation or in association with energy storage systems [6][7][8]. In this context, some works have explored the characteristics of the OPF to analyze the impact of the expansion of distributed generation on transmission line loading [9], on the presence of domestic electric vehicles in power grids [10,11], on high-voltage direct current connections [12,13], and in frequency control actions [14].…”

Electric Vehicle Charging Strategy for Isolated Systems with High Penetration of Renewable Generation

“…However, a massive introduction to the grid could create negative impacts [5][6][7][8], and create new challenges for the power systems [9,10]. In particular, a massive introduction of EVs in distribution networks that have a high penetration of renewable electricity generation is even more complicated because of some issues, such as impacts on the performance of parking lot operators [11], power systems security [12], and planning of RES Sources [13]. Thus, in recent years, some researchers have studied solutions for mitigating the adverse effects of EVs and also for creating new opportunities for the grid.…”