A Two-Step Framework for Energy Local Area Network Scheduling Problem with Electric Vehicles Based on Global–Local Optimization Method

Xin Li,Yuling Fan,Xiaodi Zhang

doi:10.3390/en12010195

Abstract

To reduce the fluctuation of renewable energy (RE) supply and improve the economic efficiency of the power grid, the energy local area network (ELAN), which is a subnetwork of the energy internet (EI), plays an important role in specific regions. Electric vehicles (EVs), as virtual energy storage (VES) in ELANs, are helpful to decrease the fluctuations of RE supply. However, how to use EVs in ELANs is a complex issue, considering the uncertainties of EVs’ charging demand, the forecast data errors of RE sources, etc. In this paper, a typical ELAN structure is established, taking into account RE sources, load response system, and a distributed energy storage (DES) system including EVs. A two-step optimization framework for ELAN scheduling problem is proposed. A global optimization model based on forecast data is built to maximize the income of ELAN, and an online local optimization model is introduced to minimize the correction cost utilizing prior knowledge. Finally, the proposed two-step optimization framework is applied to a series of real-world ELAN scheduling problems. The results show that DES system with EVs can reduce the volatility of RE supply evidently, and the proposed method is able to maximize the income of the ELAN efficiently.

Highlights

The increasing depletion of fossil energy and deteriorating global environment have led to the development and utilization of renewable energy (RE) [1,2,3,4]
A global optimization model based on forecast data is built to maximize the income of energy local area network (ELAN), and an online local optimization model is introduced to minimize the correction cost utilizing prior knowledge
A global optimization model based on forecast data is built to maximize the income of the ELAN

Summary

Introduction

The increasing depletion of fossil energy and deteriorating global environment have led to the development and utilization of renewable energy (RE) [1,2,3,4]. To improve the utilization efficiency of these increased intermittent renewable sources and promote economic development, the energy internet (EI) has gradually evolved into a new energy structure based on smart grid technologies, which contain RE sources, and distributed energy storage (DES) systems and load [5,6]. To decrease the dependence on the main grid and take full advantage of the distributed energy resources (DERs) in specific regions, EI is usually divided into several small-scale energy local area networks (ELANs), which have a far-reaching impact on the demand side [7,8]. VES is an energy management method, by which the energy of the system is balanced in the time dimension, utilizing the non-energy storage devices and scheduling strategies, showing the characteristics of energy storage [11,12,13].

Results

Discussion

Conclusion