INCH Duo Smart Charging Solutions On Level of Back Office (Software solutions)
3. Smart Charging Solutions On Level of Back Office (Software solutions)
Software solutions represents power management solutions that are done by the back-office software. Etrel Ocean monitoring system can be used. All charging stations that use OCPP 1.6 protocol can be managed by the software.
All the software solutions on level of back office can be used together with the power management functions on the level of charging stations.
Main software power management solutions:
Cluster management
Demand response activation
Load area power management
Power Management
Basic power management is performed on individual charging station and consist of several settings and is supported by other functionalities. It can also be performed on the level of back end for load areas, sub load areas, or individual charging stations. Limitation in using only software solution is the communication. If the communication between the charger, other charging stations of the cluster and back office fails, new schedules and power management can't be communicated to the charging stations.
Best case scenario is using combination of both options which represents a safe failback to the cluster management on level of charging stations in case of communication loss.
Cluster Management
Solution for power management of clusters using software (monitoring system) is very similar to the solution of cluster management enabled on the level of the charger. The main difference is that cluster master is not used, as back office software works as a cluster master and delegates the schedules and charging power values to each charging station that is part of the cluster.
Charging station sends heartbeat signal to the back office every X minutes (heartbeat frequency can be set in the back office settings module), if there is no response message received from the back office charging station immediately goes to the power fallback mode where output current of the charging station is reduced to the minimum value (usually 6 A per phase).
This is done to minimize the possibility of overloading the grid or connection point during the communication failure. If this is not done problems can especially occur when new EVs arrive to charging station during the time with no communication with software back office. If there are other (unmanageable) loads in your cluster, then software solution cannot perform cluster power management.
Figure 6: Managing of cluster from back office
Larger cluster (up to 300 electric vehicles) is possible with use of industrial computer and connection to Etrel Ocean management software.
Demand Response Activation
In some cases, the demand response functionality is needed. Distribution system operator can set the rules, that can be implemented in Etrel Ocean to enable the control of charging stations operation:
Remote power manipulation by DSO.
Remote power manipulation by energy supplier.
Load Area Power Management
Load area power management allows operator to group charging station and clusters into load areas. Software allows operator to manage the power of each load area separately. This gives operator ability to manage power only in the area where problems occur.
When charging station are grouped into one load area, the whole load area then acts as one charging station. For example, if the operator decreases the charging power of the load area for 50 kW, charging power of all the chargers in the area will reduce for 50 kW, some will reduce more and some less depending on the charging preferences on each individual charging station.
Charging station can be part of multiple load areas. One load area that represents a big part of the electrical grid, can have multiple small sub load areas, where only one or few charging stations can be in one of them. The limitation of currents can be set on the level of load area and level of sub-load areas independently. Example of load areas can be seen on the following figure.
Figure 7: Load area and sub load areas
How load areas and sub load areas are arranged and how the operator then manages power can be set completely arbitrarily. Power can be managed for the whole load area LA1 or only for each sub area (LA 2, LA 3 and LA 4) separately.
Two integration options of such system exist.
In the first option Etrel Ocean gathers all the data from each charging stations separately and aggregates them with the data from charging station from the same load area. This data is then exchanged with the smart grid system which controls the grid (other power plants and consumers).
In the second option, the data from each charging station (grid connection point) is sent to the smart grid system and it is that system responsibility to aggregate data to load areas and sub load areas and to manage power consumption of all load areas.