Electrical system

from Wikipedia, the free encyclopedia

The on- board network refers to the entirety of all electrical components in vehicles such as automobiles , airplanes , ships and trains . The term on-board network is used in general for almost all vehicles. The on-board network is responsible for the power supply (on-board power supply) and the flow of information between components and control units (on-board communications network).

The term electrical system voltage is used synonymously for the electrical voltage or the nominal voltage on board of vehicles.

The electrical components of an on-board network include u. a .:

Usual tensions

The following table shows the nominal voltages of different electrical systems. If a battery is charged via the vehicle electrical system, the actual voltage is above the nominal voltage, e.g. B. up to 14.4 V for a car electrical system with a 12 V battery. The feeds are typically made by means of accumulators and generators, which depend on the respective application:

application Nominal voltage [V] Direct (DC) or
alternating voltage (AC)
USB charging / supply voltage on e-bikes, in cars, trains and long-distance buses 5 DC
USB charging / supply voltage type USB-PD ( Power Delivery ) 5, 12, 20 (negotiated between devices) DC
USB charging / supply voltage type PPS (Programmable Power Supply ( USB-PD Version 3.0)) 5–20 (negotiated between the devices) DC
Bicycle powered by a dynamo for lighting 6th AC
Electric bike, drive battery 24 (old), 36, 48 V nominal voltage DC
Hover, balance boards 36, 53.4, 73.6 DC
Historic cars (built until 1970) and motorcycles 6th DC
Passenger cars (cars), small boats, modern motorcycles 12 DC
Lorries (trucks) and buses 24 (USA often 12V) DC
Planes 28 DC
Forklift 12, 24, 48, 80 DC
Designed in the 1990s for cars, trucks and buses 42 DC
As a second electrical system for cars, especially hybrid vehicles 48 DC
TWIKE , light e-vehicle 336 DC
As a second on-board network for electric vehicles 380-420 DC
Rail vehicles
(battery voltage)
110 DC
International Space Station (ISS) 124, 28 DC
Bigger planes 115/200 AC (three phase),
400 Hz
Sport boats (motor boats, sailing ships) 12 or 24 DC
Ships 400, 440 or 690 AC (three phase),
50 or 60 Hz
Space travel - Apollo-13 supply module (1970) 28 DC
Spaceflight - Apollo 13 Launch Pad 65 DC

Larger ships with on-board network outputs of around 5  MVA have an additional medium voltage level of 6.6 kV to 11 kV.

48-volt vehicle electrical system

The power consumption that modern vehicles need for their comfort systems can hardly be covered with the 12-volt electrical system. The “static” consumers fully utilize the alternator, which has an output of up to 3 kW, especially at low temperatures. The battery power is not sufficient for additional dynamic loads, such as powerful, electrically driven compressors .

Therefore, at the end of the 1990s, the proposal was made to install a 14V / 42V electrical system in motor vehicles. From 2001, Japanese manufacturers and General Motors brought hybrid vehicles with this electrical system onto the market. Although Daimler-Chrysler was one of the initiators of this concept, it was not used in Germany. One reason is that it did not seem possible to provide the customer with a corresponding utility value for the necessary additional price.

Instead, since 2010 German automobile manufacturers have favored the solution of providing a second sub-electrical system with a voltage of 48 volts, which supplements the 12-volt network. The first series applications of 48V on-board power supply components in 2016 are the operation of the electric compressor in the 4.0 TDI of the Audi SQ7 and the electromechanical roll stabilization in the Audi SQ7 and Bentley Bentayga . Both are based on the same platform.

Passenger ships

At the time of the large steam liner ships, around 700 kW of power for lighting plus around 600 kW for electric drives were required for up to 20,000 tons of displacement. Modern cruise ships have a displacement of up to 250,000 t and an electrical power requirement of 140,000 kW. (Last updated 2012)


  • Konrad Reif (Ed.): Bosch car electrics and car electronics: vehicle electrical systems, sensors and electronic systems. 6th completely revised and expanded edition. Vieweg-Teubner, Wiesbaden 2011, ISBN 978-3-8348-1274-2 .
  • Klaus Heuck, Klaus-Dieter Dettmann and Detlef Schulz: Electrical energy supply: Generation, transmission and distribution of electrical energy for study and practice. 8th edition. Vieweg-Teubner, Wiesbaden 2007, ISBN 978-3-8348-0736-6 , chapter structure and function of on-board networks .

Web links

Individual evidence

  1. USB-PD - USB Power Delivery elektronik-kompendium.de, accessed December 22, 2019.
  2. USB-PD - USB Power Delivery elektronik-kompendium.de, accessed December 22, 2019.
  3. voltage of battery pedelecforum.de, Posts 13th-14th July 2013, accessed December 22, 2019.
  4. Battery suitable for Hoverboard 36 Volt Gyropode Hoverboards, Viron, Razor, Caterpillar, 4400mAh, 10S2P / 22P-SL088 ...
  5. Accessories and spare parts for Ninebot Mini Pro 320 and 260 / Street ninebot-shop.at, accessed December 22, 2019.
  6. Segway PT Battery ptpro.de, accessed December 22, 2019.
  7. Still: Data sheet for stackers. (pdf) In: Stihl website. Retrieved May 7, 2018 .
  8. German car manufacturers set standards with the “Ludwigsburg Declaration” ( Memento of April 24, 2012 in the Internet Archive ) Hüthig GmbH Internet portal , July 15, 2011.
  9. ^ A b Alfred Vollmer: German OEMs set standards. 48 V on-board network, partial network operation and charging interface. In: All-Electronics.de. Hüthig GmbH specialist portal, June 14, 2011, accessed on December 21, 2015 .
  10. Cars under high voltage: Manufacturers are preparing the third electrical system Handelsblatt online, "Auto" section, September 13, 2012.
  11. The battery twike-center-ruhrgebiet.de, accessed December 22, 2019.
  12. Even more power and efficiency - the new 48-volt technology from Audi Audi Media Center, August 25, 2014.
  13. Electric biturbo
  14. a b Henning M. Hauenstein: Evolution of the on-board network architecture through 48-V supply bus. In: elektroniknet.de. WEKA Fachmedien GmbH, July 9, 2013, accessed on December 21, 2015 .
  15. Tatsuo Teratani, Toyota Motor Corporation: Future Vehicles and Trend with Automotive Power Electronics and Hybrid Technology. (PDF; 3.8 MB) (No longer available online.) In: FT3-1.2. VDE Congress 2006, October 24, 2006, archived from the original on December 27, 2015 ; accessed on January 5, 2016 (Slide 22 of 30 shows vehicles with a 42 V electrical system that went into production between 2001 and 2004). Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.vde.com
  16. G. Ackermann and K.-H. High-rise: Electrical systems on ferry and cruise ships hochhaus-schiffsbetrieb.jimdo.com, Hansa magazine No. 3/2012, short version on the company's website, 2012, accessed December 22, 2019.