Vitesco Technologies is preparing the series application of its High Voltage Box. The modular system makes charging, converting and distributing electricity in electric vehicles cheaper by integrating several functions in one unit, depending on the design: This includes the vehicle On-Board Charger for AC charging on the grid with up to 22 kW of charging power, a DC current converter providing the current for the 12 V vehicle net, and power electronics which distribute high voltage power in the vehicle and facilitate fast DC-charging with up to 800 V.
Owed to the high level of mechatronic integration, the High Voltage Box has smaller space requirements to the vehicle while increasing the total system reliability in comparison to individual devices. State-of-the art silicon carbide (SiC) semiconductors boost charging efficiency to over 95 percent which lowers the vehicle owner’s electricity bill. This efficiency level is particularly beneficial for car owners because electric vehicles are frequently charged on the grid. Due to the high AC charging rate of up to 22 kW the High Voltage Box charges the car with 200 km of range in under two hours. DC high-power charging with up to 800 V achieves the same range in 12 minutes. The sophisticated power electronics ensure that this system offers electrical safety as well as efficiency.
Today, the so-called On-Board Charger (OBC) for charging with alternating current (AC) on the grid is a separate device in the vehicle. This OBC inverts grid power to direct current (DC) that can be fed to the high voltage battery. Another separate device is the DC/DC converter which provides direct current from the high voltage battery to the 12 V power net – or it boosts 12 V to high voltage DC. A power electronics unit distributes high voltage current within the vehicle (hence: Power Distribution Unit, PDU). In addition, these electronics can be designed to allow DC charging with up to 800 V at high power charging points. All those components need to be connected, they require a housing, installation space, and cooling.
Within the modular design Vitesco Technologies covers all relevant European and worldwide grid topologies: The High Voltage Box was developed to support modular vehicle adaptation for the global market. At the same time, Vitesco Technologies is driving new functions ahead. The High Voltage Box for one of the two series applications will already function bidirectionally so that it can supply alternating current with 230 V from the DC battery current when this is required. This puts vehicle owners in the comfortable position to make versatile use of their large battery: For instance, if they wish to use power tools far away from the grid, or if they want to feed electricity to the grid which they have charged earlier from their own photovoltaic system.
In the future the High Voltage Box with bidirectional function can also make it possible to power a whole house from the High Voltage Battery during a blackout. This is an option because batteries in vehicles have a much bigger capacity than most of the batteries typically installed in private homes.