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Coordinated charging is characterized by charging EVs in coordination with the utility grid. The coordination is required to identify the present condition (load connected) of the grid or power source that will supply the power to charge EVs. The peak load and off-peak load hours of a utility grid vary based on residential, industrial, or commercial regions. In general, for the residential area, the utility grid is in peak load at evening and night hours, while the off-peak load hours are noted during late nights when people sleep. The load demand for an industrial area will depend on the working shifts and operation of factories. For commercial areas, the peak load hours will be at consumer visiting hours, i.e., during the evening. The off-peak load hours will be during the morning [6, 15].

In the case of coordinated charging, based on the regions, the process of charging is scheduled during off-peak load hours. However, it is ensured that EV owners are not barred from the services. The literature is flooded with works done to perform coordinated charging by developing optimizing algorithms, demand response strategy, load scheduling, controllers, dynamic pricing methodology, electricity market operation strategy, and time of use (ToU) [16-22]. Although the works in the literature are diverse, each of them shares the following common goals:

1 a. The EV owners’ need to charge at any time of the day should not be denied, irrespective of the loading in the utility grid

2 b. The power system operator (PSO) constraints should be coordinated and supported in the quest to charge EVs

3 c. Necessary support services from the EV owner to the PSO and the PSO to the EV owners should be provided via necessary coordination

4 d. Increased penetration of local energy storage and renewable energy sources in the utility grid

Coordinated charging of EVs is complicated, expensive, and needs standard infrastructure support for implementations. However, the benefits are immense compared to uncoordinated charging. Coordinated charging helps solve two major issues: first, congestion management, which is defined as an increase in thermal loading in transformers and cables and, second, voltage drops, which are most commonly experienced due to the addition of any unprecedented load, such as EVs [15, 23-25].

The type of charging is also a significant factor to be considered when working with coordinated charging [8, 11]. A fast-charging requires a higher amount of power to be transferred to the EV batteries in a short duration of time. In contrast, in slow charging, the requirement of power is reduced, but time is increased. The ToU and dynamic pricing algorithms are the most commonly presented in the literature to cater to the requirements of power for different charging types. Although coordinated charging solves the basic requirements of charging EVs in consideration to the utility grid’s constraints and managing EVs as a load, it fails to be a future proof system where both the EV owner and the PSO are guaranteed an optimized charging process [10, 18].