Hitachi ABB Power Grids has presented Grid-eMotion Fleet, a ‘grid-to-plug’ charging system for electric buses with a system-based approach. The solution has been developed to charge more vehicles with less infrastructure.
Grid-eMotion Fleet is a DC charging solution. The charging system consists essentially of standard containers in which all the grid connection and charging systems are installed together. This should make it easier to electrify bus depots of public transport operators and the parking spaces of electric truck fleets.
Specifically, Hitachi ABB Power Grids says that compared with a conventional connection to the AC grid, the solution should offer a 60 per cent reduction in the space required to charge a large fleet. At the same time, depot cabling is reduced by 40 per cent. The system will be an asset to “anyone managing public transport and commercial EV fleets,” says Niklas Persson, Managing Director of the Grid Integration Business Unit at Hitachi ABB Power Grids.
Depending on the configuration chosen, the charging capacity is between 50 and 600 kW, and various pantograph chargers are possible in addition to wired CCS charging. The charging points themselves have been kept very simple, and in the CCS version offer touch screens in addition to one or two 4.5 metre long cables to start the charging process.
The charging point communicates via CAN bus or Ethernet with the container, which houses both the rectifier and the DC-DC converters. The rectifiers have an output of between one and three megawatts, the DC-DC converters then make this output available to the respective charging points. On request, the system can also be extended by a stationary battery storage unit, which can provide up to 500 kW power and 670 kWh energy content.
The charging solution also uses an intelligent energy management solution from the company, called ‘e-mesh EMS’. This is used to manage the entire charging infrastructure, calculate the energy consumption of the buses and thus, according to the developers, ensure a reliable transport service.