# An EV Charging Scheduling Mechanism Based on Price Negotiation
## 1 Introduction
The authors of [19] used the adaptive price control based on neuro-dynamic programming for EV charging with the consideration of energy supply limitation to tune the EV charging demand to approach the expected level by learning from the EV charging process and EV mobility. The authors of [20] proposed and implemented a smart EV charging algorithm to control the EV charging infrastructures according to users' price preferences. EV drivers can submit their price preferences and daily travel schedules to negotiate with the Control Center to consume the expected energy and minimize charging cost simultaneously. The above-mentioned research intends to improve the efficiency of the whole EV charging system and to bring more benefits and convenience for each participant of the system by establishing a reasonable charging price model and strategy. However, these approaches mostly develop the pricing mechanism from the point of view of the charging station operator or EV user, with the additional consideration of load shifting and the utilization of renewable energy resources. The thorough interaction about charging price between the charging station operator and EV users, according to their own interests and actual requirements, as well as the consequent change in charging price, have not been considered in depth. One of the two parties is the passive participants in charging pricing, which leads to their relatively lower consequent satisfaction. Therefore, a dynamic charging pricing mechanism that both charging station operator and EV users can actively participate in to improve their participation and satisfaction is needed. To solve this problem, one effective idea is to switch from the existing charging pricing mode to the charging price negotiation mode. Price negotiation has been widely applied in the field of electronic commerce [21; 22], and recently, a real-time pricing mechanism via distributed negotiations between prosumers in the smart grid is discussed and its feasibility proved [23]. Price negotiation transforms the price formulation into a process of reaching an acceptable price for each party. With this price negotiation mode, the balance between interests and the actual requirement of most participants will be reached once a price is accepted by all of the participants, which leads to relatively higher consequent satisfaction. However, in reality, human behavior is complex, and people are not entirely rational in the process of price negotiation. Therefore, a dynamic and reasonable charging price negotiation model is needed. Based on the above analysis, we mainly studied the EV charging scheduling problem based on price negotiation. Our first contribution to the field was the establishment of a charging price negotiation model. Our second contribution was the proposition of an EV charging scheduling mechanism based on price negotiation (CSM-PN). The rest of this paper is organized as follows. In Section 2, the EV charging system framework based on price negotiation is introduced. In Section 3, the price negotiation model is presented. The charging scheduling mechanism based on price negotiation is discussed in Section 4. Simulation results are analyzed in Section 5. Section 6 draws the conclusion.