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H/O and H/E alternator part 2

Started by mobile_bob, November 23, 2009, 08:37:50 PM

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mobile_bob

thought i would present the next generation of testing i want to persue with the project X alternator

feeling certain that i can attain the 130amp output at 57.6vdc (the normal voltage for bulk charging a 48volt
nominal flooded lead acid battery bank at 77 degree's F ambeint temps) it was always in the back of my mind
that i do not need to maintain the 130amps for a very lengthy time before the amperage requirement begins to fall
off substantially, at which time running at full 1800rpm is unnecessary.

so the next move is to relocate the rectifier bridge from the alternator to a remote location and seperate each phase
so that each phase can be brought out to switch gear so that i can connect either in the oem delta configuration for
high amperage, or in the wye/star configuration for lower amperage (approx 57% of delta connection current) which would
allow me to drop the engine rpm substantially to ~1000rpm. The engine will run at 1000rpm but really likes 1200rpm better
and it fuel consumption drops significantly in the process.

in order to accomplish this scheme the switchgear will be comprised of a standard three phase reversing contactor set
connected so that i can take the output from the alternator in delta or wye, but only one or the other without possibility
of crossconnection which would result in a short and likely damage windings. the reversing contactors are mechanically
as well as electrically interlocked making connection of both configurations at the same time impossible.

the second needed item is a solenoid to trip from low idle 1200rpm operation and high idle 1800rpm operation, that can
be done easily with a standard fuel cutoff solenoid and a bit of linkage/springs/design.

the third thing is a tie in to the balmar controller to signal the microcontroller engine management system to take over control
of the switching of stator connetion and the stepping from low to high idle speed and visa versa.

this system approach will do a number of things,

1. lower fuel consumption during the absorption phase of charging and certainly during equalization of the batteries

2. lower engine rpm resulting in longer engine life, longer service intervals possibly as well, and

3. dramatically lower noise in db produced by the engine.

the upside of such a system is the feedback loop where a current sensor could determine whether the inverter was providing
for a load sufficiently high to warrant stepping the engine back to full 1800rpm operation and switching the stator back to delta
connection for the added amperage needed to provide for that load, or leave it alone at the 1200 rpm level.

this will provide three levels of operation,

1.engine off loads serviced by batteries and inverter alone,

2. engine low idle, provideing charge for batteries and also for light loads thru the charge/battery/inverter, or

3. engine high idle operation, provideing for charging and heavier specific loads thru charge/battery/inverter, and
also have the ability to switch in the st head if need be to provide for specific loads such as a well pump or other
heavy load that needs to be serviced.

bob g

EBI-WPO

Bob,
Sounds neat. Don't you need more than 3 contacts to change from Delta to Wye? Seems like the center connection can't be made all the time and would require another set of contacts for isolation.

Terry
To have B.S. aimed at you is an insult to your intelligence......To have B.S. spread about you is an insult to your character.....Neither should be tolerated willingly.   EBI-WPO 2010

mobile_bob

i think i can do this without the fourth set, only because i don't need access to the center of the wye
although it would appear i could gain access easy enough

check out the attachment

bob g