Control is carried out on the basis of data analyzed by the EVEMS to modulate or interrupt charging, depending on established priorities and capacity limits. This control can be applied at two main levels:
- From the electrical infrastructure (“control at the source”): This method regulates the power supply upstream, i.e., at the electrical panel or the power source for the charging stations. The major advantage is that it is compatible with any brand or model of charging device, including those that connect to a simple NEMA-14-50 outlet. This offers great flexibility in the choice of charging stations.
- From the charging device itself (“control by the charging device”): In this case, the EVEMS sends commands directly to the charging stations to adjust their power or turn them off. For this method to work, it is generally necessary to standardize the brand or model of the installed stations to ensure their compatibility with the existing energy management system.
The choice of control location (at the source or by the device) will impact the flexibility of the installation and the need to standardize charging equipment.
Effective control is essential to ensure the electrical safety of the building and maximize the number of vehicles that can be charged simultaneously, while respecting the limitations of the existing infrastructure.