4. Involving experienced project partners
Despite existing standards, the implementation of a charge management system is not simply a case of “plug and play”. The greatest challenge faced in any project is establishing high quality and standard compliant communication between the components. The standards need to be implemented correctly to ensure that the data content meets the requirements of availability and depth of detail. This makes it even more important that a suitable charge management provider can demonstrate sufficient expertise in implementing these standards (Figure 2).
Whereas communication using OCPP often works well, “preconditioning the vehicle” as required by VDV specification 261, still requires a considerable amount of implementation work. CarMedialab collaborates with different vehicle manufacturers to support implementation and ensure correct preconditioning. Adopting ISO 15118 (communication between charging station and vehicle) also requires a great amount of detail and a high level of expertise, coordinating with vehicle manufacturers.
A further standard is important to ensure the smooth operation of electric buses as it is important to know certain vehicle conditions at all times, such as the charging status and the remaining battery capacity: the standardized FMS interface for transferring vehicle data to the on-board computer. Data availability and the quality of data transferred is hugely important as the range is limited by current battery capacities and doesn’t allow reserves for several days of operation, the energy consumption of electric buses depends on a range of factors (such as the topology of the route, the driving style, and especially, air conditioning the vehicle) and the range does not decrease linearly as a result. These are not yet available to a sufficient degree in all vehicles. In addition, the FMS interface which was originally developed for diesel motors does not yet have enough e-mobility parameters. A detailed standard is therefore required, which should be regulated by the pending VDV 238 specification. Until then, a competent partner in implementing charge management systems is essential to support the data transfer.