Direct Load Control Decision Model for Aggregated EV Charging Points

Abstract

This paper details a decision model to implement direct load control (DLC) on battery charging processes at electric vehicle charging points located at parking areas. The programming model combines optimally three types of energy management decisions: grid-to-vehicle charges, vehicle-to-grid discharges, and novel vehicle-to-vehicle energy exchanges. The objective function maximizes the net energy supplied to batteries minimizing simultaneously the global energy cost. A 50-plug-in vehicle park case is analyzed for three possible mobility patterns: household, commercial and mixed. Outputs from the DLC model are compared with the ones using a dumb charging policy from the service quality and economic points of view. Finally, a sensitivity analysis has been done to evaluate the economic impact of the Depth of Discharge condition to preserve battery lifecycle of electric vehicles. Index Terms-Charging points, direct load control (DLC), electric vehicle batteries, grid to vehicle, vehicle to grid, vehicle to vehicle. NOMENCLATUREHere, we provide the main nomenclature used for quick reference of acronyms and elements of the programming model. Lower-case symbols denote indexes and parameters, and uppercase symbols denote variables. A. Main Acronyms[1] EV/EVB Electric vehicle/electric vehicle battery. PHEV Plug-in hybrid electric vehicle. EVCP Electric vehicle charging point. DLC Direct load control. AU/CAU Aggregation unit/central aggregation unit. G2VGrid-to-vehicle charging process. V2GVehicle-to-grid discharging process. V2VVehicle-to-vehicle energy exchange. B. IndexesType of plug-in vehicles {EV, PHEV}.

Day-ahead optimal charging/discharging scheduling for electric vehicles in microgrids

“…However, many existing literatures have focused on the intelligent charging strategy [15][16][17][18][19][20] in distribution grids, although discharging management [21][22][23][24][25] has attracted increased attentions in recent years. Smoothing the daily load profile is considered to be the most important issue [15-17, 21, 22] whereas electricity price and economic benefits of EV owners are the main motivating factors to obtain load leveling [17].…”

Optimal Charging Scheduling of Electric Vehicles in Smart Grids by Heuristic Algorithms

“…A number of studies were performed on the impact of EV integration into power systems [26][27][28][29]. A study shown in article [27] attempted to maximise the amount of energy that can be delivered to all the EVs in a fixed period of time taking into account network technical limits and using a linear programming methodology.…”

“…However, the behaviour of electric vehicle users is not considered in the formulation of the problem. In reference [28], a direct load control management technique is developed to maximise the net energy supplied to the batteries and simultaneously minimise the total energy cost by incorporating charging patterns of a plug-in electric car; however, the technical network limits are not included in the problem formulation. In [29], the authors use the coordination of EV charging by considering EVs as distributed energy resources to smooth the load profile.…”

Optimal Planning of Charging and Power Delivering from/to the Network for Electric Vehicles Considering Types of Trip

“…Reference [14] has tried to minimize the overall cost according to different charging patterns of electric vehicle. In [14], the impact of a direct load control program for management of electric vehicle charging process is analyzed.…”

“…In [14], the impact of a direct load control program for management of electric vehicle charging process is analyzed. A novel method is proposed in [1] for load control of electric vehicle charging in response to time of use (TOU) pricing.…”