In today's vehicles, adding a new function in the pre-existing Electric/Electronic Architecture (EEA) is often accomplished by the incorporation of one ECU connected to its own sensor & actuator components. The increasing number of ECUs in vehicles becomes critical in term of integration into the vehicle since available space for electronic is no longer maintained. In term of complexity it also leads to an increase of wires, communication networks, energy management and so forth. Thus disruptive solutions are required to reduce numerous wires & ECUs and to optimize energy consumption. The introduction of PLС in the vehicles, combined with increased use of mechatronics, is a possible solution.
For a middle range or C segment vehicle, we can consider a total of 35 embedded ECUs, 20 ECUs for the power train, chassis and HMI & multimedia domains. For the body & comfort domains, 15 ECUs are implemented within around 100 sensors and actuators. Only some integrate an electronic module within the mechanical part we call mechatronic modules and only a few of these ECUs are mechatronic types.
Regarding the diversity of actuators we consider using the PLC solution on the small and medium actuators which are used for mechanical movement in the door and seat areas where, for the sensors, the electronic characteristics do not impact the PLС solution and the mechatronic size. Indeed, the range of the average current for these actuators is from 1 to 10 Amps with a maximum inrush current of 25 Amps in few cases. The command is either very simple or uses a low frequency PWM. The response time of these functional systems is around 200ms within a sensor signal response in the range of 20 to 200Hz maximum.
The wiring harness in this body & cockpit area can count more than 700 wires which means more than 1,3km of wires, 1400 connexions and 25kg weight. For instance, the driver door can integrate up to 50 wires for the locks and the contacts, the anti-pinch window lifter, the mirror, the control panel, the several lights, the free handle system, the loudspeakers, etc. The number of wires in an electrical seat reaches a similar level.
Body and cockpit are heavily wired areas in the vehicle. They offer a great cost reduction opportunity for Power Line Communication (PLC) especially in door and seat sub-systems.
This article looks at how implementation of a robust PLC protocol allows drastic harness weight reduction. The article describes the practical implementation of distributed power management in seats, doors and lighting subsystems.
To read it, click here.
About the authors
Eric Fitter is project leader in advanced engineering for EEA systems at PSA Peugeot Citroen. In 1999 he received an engineer degree in Electronic Engineering with a specialization in sensor and instrumentation from the ENSEA of Cergy Pontoise (France).
Philippe Briot obtained a General Engineering degree from the Gramme Institute and post-graduated in Telecommunications and Microwaves at the University of Louvain la Neuve (Belgium) where he worked within the Microwave Research Lab. In 2002 Mr.Briot founded Briot & Associates, a company composed of high profile engineers providing support and consultancy in EEE components, EE systems, new technologies insertion and innovation management.
Igor Ablaev graduated 1992 in engineering and physics at Saratov State University and 2004 in management at International Institute of Management “LINK” . He is winner of the all-Russia competition “Presidental Program: Manager of the 21st Century”. In 2000 he launched the Finprom-Resource Industrial Group and started to develop control system for on-board vehicle nets (AVAS).