# Modeling and Solving Method for Supporting Vehicle-to-Anything' EV Charging Mode
## 1 Introduction  
Electric vehicles (EVs) are an attractive transportation option that provides appealing benefits by reducing the use of fossil fuels with high energy efficiency and combatting CO\({}_{2}\) emissions. As an alternative to traditional petrol or diesel vehicles, EVs are now receiving unprecedented interest from numerous users, investors, and countries [1; 2]. According to a recent report on the global electric car stock, worldwide sales of EVs have hit a new record with over 0.75 million in 2016 and the transition to electric road transport is likely to keep growing over the coming decades [3]. The fast development of EVs has also attracted researchers into power systems. EVs should rely on power grids in procuring energy for voyage support. To accommodate the charging of EVs, certain infrastructures such as charging stations, a communication link, and a control interface and system must be developed or implemented. The penetration of massive EVs will also challenge the operation of the power system, since the additional load of EV charging may potentially amplify the daily peak of power load curve and induce some adverse impacts including voltage drops, frequency oscillations, power congestion [4; 5], etc. Besides the load impact, it is also expected that an EV can direct energy back into the power grid by utilizing the discharging activity of the EV battery. This envisaged technology is well known as Vehicle-to-Grid (V2G) technology [6]. With V2G enabled, EVs can act as moving energy banks, capable of procuring energy from the power grid and also injecting energy back when necessary. Therefore, the power flow of V2G can be unidirectional (charging only) or bidirectional [7], and EV owners have the opportunity to earn extra profit through charging their cars at low-price time slots while selling energy back to power grid during periods with high power prices. The discharging ability also enables EVs to participate in other various charging/discharging activities such as home energy management (V2H, Vehicle-to-Home) [8], building energy management (V2B, Vehicle-to-Building) [9], and charging station energy management (V2V, Vehicle-to-Vehicle). In essence, these discharging behaviors are operated to compensate for the power demand from other loads, thus achieving the optimization of energy consumption and operational costs for certain power consumption entities or communities (home, building, charging station, residential area, and so on). The above EV discharging activities, including V2H, V2B, V2V, and V2G, can be uniformly named the 'Vehicle-to-anything' (V2A) charging mode [10]. In [10], a thorough discussion of V2A scenarios is given, including the challenges and opportunities involved in this technology. To support the various charging/discharging activities of V2A, communication infrastructures and technologies are needed for essential information exchange [11; 12]. In addition, it is also advised to develop and apply the 'Vehicle-to-anything' app for EV energy management [13]. Previous studies gave some basic concepts/future expectations of V2A [10; 11; 12; 13], or only focused on the partial application of this charging mode (V2H, V2G, or V2B) [8; 9], while the modeling and supporting approach for a more comprehensive utilization of V2A technology is still insufficient. In order to support the V2A scenarios, its charging activities are investigated. The aim herein is to develop a solving model that can adapt to V2A technology. The main contributions of this work lie in:  
1. Based on basic findings of V2H, V2B, V2V, and V2G, all the applications of V2A are considered and a generic model that can adapt to V2A is proposed;
2. Besides the consideration of EV charging satisfaction for EV user, battery degradation that can affect EV charging/discharging behaviors is also considered in the model through the evaluation via battery charging/discharging cycles;
3.