Re: Mystery Motor/Generator with some clues
- From: Tony Williams <tonyw@xxxxxxxxxxxxxxxxxxx>
- Date: Thu, 01 Jun 2006 08:39:14 +0100
In article <127ki3ak1u3bm5a@xxxxxxxxxxxxxxxxxx>,
Paul E. Schoen <pstech@xxxxxxxxx> wrote:
The generator seems to be fairly simple. It is specified as a 3[snip]
kW, 110 VDC, 27 amp, shunt wound machine. There are two heavy
wires which are connected to the brushes and the rotor, and they
read about 2 ohms. I assume this is the output. There are two
other pairs of wires, one of which reads 150 ohms, and the other
is about 1.65 k. The drawings I have show only two pairs, A-AA
for the armature, and X-XX for the field. I would assume the 150
ohm winding would be connected to 110 VDC through a variable
0-250 ohm resistance.
A shunt-wound generator will not self-excite unless
the total field resistance is below a certain value.
I did an AVR a year or so ago, for a 28V/300A DC
generator. The 2-ohm field required about no more
than 1-ohm in series with it to self-excite, then at
18V terminal voltage I could switch the resistor out
and let the PWM'd regulator start controlling it.
I also had a diode in series with the field so that
it would not self-excite with a reversed remanence.
The contactor that switched the regulator in also
shorted out the diode.
--
Tony Williams.
.
- Prev by Date: Re: RoHS AKA Woah, Hoss!
- Next by Date: Re: Maximum current for TO-220 package 75-95A, and how to connect heavy leads
- Previous by thread: Re: Mystery Motor/Generator with some clues
- Next by thread: MOSFET question
- Index(es):
Relevant Pages
|
