Paul,  everyone.


Anyone have a Citroen dealership nearby?  I am really wanting to get one
of these units..  I saw one at the last Tokyo Motor show but none of the
sales people there had a clue what it was.  It looked just like a beefy
alternator.  ...  For our space limited applications this device could
be just the ticket.


"The STARS starter-alternator from Valeo: a brand new way of
functioning.

Using the 12V power network with a conventional battery, a special
electronic unit has been added to allow the alternator to take over the
functions of the starter motor.
In inverter mode, Valeo's reversible starter-alternator transforms 12V
direct current from the battery into three-phase current to supply the
alternator, which is effectively used as a starter motor.

In rectifier mode, Valeo's reversible starter-alternator generates the
electricity required for the vehicle. It also offers a significant
increase in efficiency (up to 15%), intelligent control of the drain
current and high outputs of up to 180 amps. These three Valeo-developed
solutions lead to additional savings in fuel consumption and optimized
battery recharging on PSA Peugeot Citroën vehicles.

The reversible starter-alternator's electronic management module
communicates with all other body controllers in the vehicle with no
modifications necessary; this facilitates the deployment of the function
for several engine and vehicle applications.

The engine starts silently thanks to the accessory belt, a new function
enabled by a special material and hydraulic damping of the tensioner.

The fuel injection strategies (for both gasoline and diesel engines)
developed for Stop & Start ensure that restart is instantaneous (400
milliseconds, i.e. twice as fast as a conventional starter motor) and
pollution free (thanks to an accelerated temperature rise in the
pollution control devices: catalytic converters, particle filters, etc.)

Zero noise, zero consumption and zero pollution at standstill

The Stop & Start system is a first step in the hybridization of vehicles
for the general public.

The concepts developed and retained, each of them innovative in their
area (55 patents filed for this project) are the result of the ongoing
drive to find simple and reliable solutions which can be manufactured in
the short term, while maintaining the current automotive standards in
terms of mounting (using the fixings of a conventional alternator),
operation (air-cooled and belt-driven) and electricity (conventional 12V
network).

An innovation that combines driving pleasure and respect for the
environment

The Citroën C3 Stop & Start, the world's first vehicle to be
equipped with the StARS system, available since last month, will be
followed by other Peugeot and Citroën models. Valeo has also
announced developments with other automakers (Ford, Hyundai, etc.)...."

Doug in Japan

Paul,

I found a picture of the Valeo STARS unit.

Doug in Nippon

Doug,
An inherent problem with this scheme is the high speed ratio required
for the starter function to work properly;  perhaps 6:1 or more.  At a
cruise engine RPM of 6000, the alternator may be spinning too fast.
Unlike DC motors, polyphase AC motors produce fairly low torque when
stalled.   The lack of moving parts in the rotary gives it a lower
static coefficient of friction than an equivalent piston engine.  So,
one of these may work on the rotary at a speed ratio of around 2:1.
This inverter box is, no doubt, designed to tailor the AC power to the
motor so that the stalled torque is maximized briefly to get the engine
moving.

Honda has a similar system on their hybrid vehicle.  Also, Mistral has
mentioned investigating a starter/alternator system.

Aubrey Thompson

This system is feasible. I have laid my hands on such a system at one
the the "Big Three".   It looks like a normal alternator except for the
large battery direct type cables running from the starter/alternaotor to
the controller.

Tom Hanks

Tom,

Sounds great.  Do you have any pictures or source info.   I will be in
the SOCAL area late September and wish to check out a unit.

Doug in Japan