Intergration of 48V wire harness in vehicles

Date Created: 2014-05-30 1

IQPC - Advanced Automotive Cabling, Stuttgart June 24 - 26 2014

Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

Peter Berggren Senior Engineer

Project leader for integration of 48V

Volvo Car Corporation

Agenda

• Background

• Tests results

• Requirements

• Conclusions

Intergration of 48V wire harness in vehicles

Date Created: 2014-05-30 2 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

Background

Why do we need 48V?

It will not replace the 12V system!

48V system will be a complement to the 12V system.

Date Created: 2014-05-30 3 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

B-ISG

48V 12V DC

DC

Z12 Z48 SM

Why do we need 48V?

• Enabler to reach CO2 requirement in 2020 in Europe.

(<95g/km)

• 12V system is close to it’s maximum capability.

Date Created: 2014-05-30 4 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

Why 48V? Personal safety limit

Date Created: 2014-05-30 6 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

Today’s Micro hybrid

12V

3kW

Future Micro hybrid

48V

10kW – 12kW

• Stop/Start • Limited break

recuperation

• Stop/Start in speed

• Brake energy recuperation

• Coasting

Mild hybrid

>60V

>18kW

• Stop/Start in speed

• Brake energy recuperation

• Coasting • Low speed

electric drive

Full hybrid

>120V

>30kW • Stop/Start in

speed • Brake energy

recuperation

• Coasting • Electric drive

g CO2/km emission Cost

Will the wires be thinner with 48V?

Yes. For components moved from 12V.

Example:

A 1000W component (e.g. heated windscreen) with 3 meter long 16mm2 wire

will change to 2,5mm2 wire. The delta weight for copper will be 390g.

For the wire between 48V ISG and battery. Yes and No.

In case of 48V kinetic energy recovery system, KERS.

The thinner we make this wire, the less CO2 we save.

Date Created: 2014-05-30 7 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

Example

12V

• 100A

• 1,5V

48V

• 25A

• 1,5V

16V

9V

18V

6V

4,5V

12V

Date Created: 2014-05-30 8 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

Voltage range of 16V Voltage range of 7V

Test EXAMPLES AND RESULTS

Serial

Parallel

Live disconnect

Ring terminal with

poorly tightened nut

Live connect

Wire dropped to plate

edge

12V 48V

Wire chafed against

plate edge

Short circuit, 48V to

12V

Date Created: 2014-05-30 9 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

48V_40A_wo_

cap_disconne

ct_YESC

48V_40A_with_c

ap_disconnect_Y

ESC

Requirements

LV148

• Within the wiring harness it is

ensured, that a short circuit,

caused by a single malfunction,

cannot occur between the BN48 and

the BN12/BN24.

Routing is very important for 48V!

• There is a common ground

potential for the BN12/BN24

and BN48, which is connected

by spatially divided ground

terminals.

Date Created: 2014-05-30 10 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

How protect a 48V wire

250A 1000A

Normal Fuse will handle Battery switch will handle

12kW

brake

energy

0A

Date Created: 2014-05-30 11 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

Conclusions

• 48V is low voltage

No personnel protection

• 48V can not directly be treated as 12V

• Below 40A we are well protected by the fuse.

• Above 40A we need an active protection as well.

Date Created: 2014-05-30 12 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

• In events of short circuit between12V and 48V, there is a

risk that the 12V system will be damaged!

Conclusions

• Connectors should be designed in such way that it is not possible to disconnect them in a slow way.

• In case of use of ring terminals it is important to have a process that makes sure that they are correct tightened.

Date Created: 2014-05-30 13 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation

Thank you all for listening!

Any questions?

Date Created: 2014-05-30 14 Integration of 48V wire harness in vehicles– Peter Berggren– Volvo Car Corporation