EMS as Man-in-the-Middle (OCPP)
An energy-management topology where EMS and local-controller functionality are combined and placed between the CSMS and charging stations.
Technical Details
By acting as a local controller in the middle, the EMS becomes aware of CSMS instructions and limits, enabling it to differentiate between “low power because the EV is satisfied” and “low power because of an imposed limit.” This awareness allows for more sophisticated energy scheduling and conflict handling between CSMS plans and site constraints.
Fleet Applications
Useful for depots with complex constraints (fuse limits, PV, batteries): energy management can optimize while respecting transaction priorities and user/vehicle needs visible in OCPP traffic.
Related Terms
Smart Charging
Intelligent management of EV charging sessions to optimize energy consumption based on grid constraints, energy prices, and vehicle schedule requirements.
OCPP 2.1
OCPP 2.1 is a newer OCPP release that extends the protocol ecosystem with clearer architecture guidance and energy-management integration patterns for smart charging deployments.
ChargingStationExternalConstraints (OCPP)
An OCPP charging-profile purpose used to represent charging limits imposed by external actors like an Energy Management System (EMS) or a smart meter.
NotifyChargingLimitRequest (OCPP)
An OCPP message used by a charging station (or local controller) to inform the CSMS that the active charging limit changed due to an external source (e.g., EMS, smart meter, DSO signal).
Local Controller (OCPP)
An on-site component that can sit between charging stations and a CSMS to perform local scheduling and load balancing, often used when integrating an EMS at a site.