Ahead of its time: high-voltage electrical system for E-Vito
Even before the introduction of uniform standards for electric vehicles, HUBER+SUHNER developed the high-voltage electrical system for the Mercedes E-Vito. With a direct connection and shielded cables, the high-voltage distributor meets all the key market requirements, such as electromagnetic compatibility (EMC), leak tightness and minimal contact resistances.
Although initial standards now exist, development of the Mercedes E-Vito began at the end of 2009 without any specifications. High voltages in the vehicle interior placed new requirements on the electrical system. HUBER+SUHNER was approached by Daimler to develop the basic principles of the high-voltage electrical system owing to its experience of this type of connection in the railway market. Magna Steyr subsequently appointed HUBER+SUHNER to develop the high-voltage electrical system for the Mercedes E-Vito.
Short development time
The special challenge was mainly due to the extremely short development time. “The time between project start and acceptance of the production process was less than one year,” says Norbert Schaller, Automotive Market Segment Manager, Germany. “We were unable to draw on past experience in the development of high-voltage electrical systems, or on existing industry-specific standards.” Due to the high voltages concerned, the customer placed various requirements on the high-voltage distributor, such as electromagnetic compatibility, tightness to liquids, low transition resistance and absolute safety. Industry-standard connectors do not fulfil these requirements. The RACS (RADOX® Automotive Connection system) interconnection system by HUBER+SUHNER, however, connects the HVDU and high voltage units in an extremely space-saving and efficient way by routing the cables directly to the distribution station.
The development, design and layout of the high-voltage electrical system, and the process design for the prototypes were all “Made in Germany”. HUBER+SUHNER agreed the validity checks in close consultation with Magna. Release sample production took place in Switzerland, with the production of the limited series in Poland. By 2014, HUBER+SUHNER will produce more than 2,000 high-voltage electrical systems for the Mercedes E-Vito, consisting of the distributor (High- Voltage Distribution Unit - HVDU), individual wires, shielded and unshielded multicore cables, as well as unshielded low voltage cables for connecting the low voltage electrical system to the power train. HUBER+SUHNER is now applying the invaluable experience gained in designing high-voltage electrical systems to brand-name manufacturers of electric and hybrid vehicles worldwide.