On 19 Jun 2005 03:39:00 -0700, wrote:

Even if I run the resistance down near zero, the LCR.EXE program still
says "No impedance hump."

Is the program broken? I doubt it.

Am I doing something wrong? I don't know.

L = 136000 uH, C = 51000000 pf, R = 23 ohms, f = 0.00006 MHz.

Doug

My earlier note assumed that you were varying capacitance or
frequency and wondered why you observed no significant hump - this
could still happen

With regard to the software difficulty I think you are misreading the
results. Using your values, the program correctly arrives at a Q of
2.2 which produces an impedance hump reaching 127ohms.

The pretty irrelevant comment "****No impedance hump" simply states
that if you increased R to 80ohms the hump would vanish.

Jim

wrote:
On 10 Jun 2005 15:00:48 -0700, wrote:



wrote in sci.electronics.design and
rec.crafts.metalworking:
I have ordered an LCR meter and a less expensive cap sub box that
should be rated 200 VDC instead of 50 VDC.

Doug

The LCR meter has arrived from Hong Kong.

The inductance of the motor coils in parallel is 112 microhenries.

The resonant capacitance is (confirm?) 62 microfarads.

There are 36 poles on this split-capacitor motor.

The synchronous speed would be (confirm?) 400 rpm.

The motor runs at 225 (rated) rpm.

The motor runs with 175/400 = 44% slip.

I need to run the motor at 400+44% = 576 rpm.

I have to do that because of the impedance protection, right?

So the efficiency will indeed be low.

At 90 pedal rpm, with my existing cog, I will need a

x * 90 / 8 = 576;
x = 576 * 8 / 90 = 51 tooth cog, which is just what I have.

However, if I splice two motors together at 225 rpm, I will have to
recompute.

I recall that damping reduces the apparent frequency of an impulse
driven resonant system, and wonder if the substantial resistance of
this impedance protected motor will reduce the continuously driven
resonant frequency, or whether my recollection only applies to impulse
driven resonant systems.

Yours,

Doug Goncz



I've picked up this thread late so I've probably missed important
bits. However the following comments may be useful.

If I've understood the post correctly you are aiming to use an
impedance protected 36 pole motor as a self excited induction
generator.

Self excited induction generators rely on the tiny residual
pattern of magnetisation of the rotor being reinforced by the current
flowing in the near resonant stator winding circuit. It has to be
operating close to resonance for the current build up to be large
enough to reinforce the rotor field pattern. It has to be on the
capacitative side of resonance to permit the phase angle of the stator
current to reinforce the rotor field pattern.

It is a positive feedback regenerative system and on a large
efficient motor the output can build up to far beyond its rated motor
power until limited by magnetic saturation. This effect is sometimes
used for regenerative braking of single and three phase motors and can
result in a spectacularly short stopping time.

With a care and control of speed, self excited induction
generator systems are possible but they're pretty touchy devices.
If you're unlucky with the the rotor iron they may not retain enough
initial magnetism to enable the output to build up (manufacturers
strive to reduce this because it degrades the efficiency when used as
a motor) Also it must use a reasonably efficient motor for the
magnetic feedback to exceed the system losses.

Efficiency is your major problem. An impedance protected motor
means a motor with deliberately large leakage inductance so that the
impedance of this inductance limits the current that flows when the
motor is stalled or overloaded. With limited stalled current the
starting torque (already poor because it is a capacitor run machine)
has to be boosted by the use of a high resistance rotor and this
results in your observed very high slip speed. Even if there were no
other losses of any kind the motor efficiency could not be any better
than the % synchronous speed - 56%. With other losses taken into
account the motor efficiency is probably no better than 40%.

With the uH to mH correction your sums are OK but this level
of efficiency is too low for a succesful induction generator.

Jim

Many thanks to Jim and other contributors to the thread "Motor
Generator Analysis".

I have put a lot of money and time into this, and I want to give it my
best shot, but I don't want to whip a dead horse, so to say.

Frankly, I don't understand magnetics. At least not as I understand
resonance. I'm an amateur musician; I understand resonance and know a
little about phase shifts near the peak. I do understand that because
the slope of the curve is negative on the high-frequency (capacitative)
side of resonance, loading of the generator, within limits, will result
in additional power to meet the load.

But B x I makes my head spin. I'm fine in 3 dimensions. So I get some
of it. And I get that in the cylindrical coordinate system, B and I can
be locally orthogonal, and can vary in time, with phase shifts, while
being wrapped into a connected topology. I just don't feel that the way
I feel resonances. It's not intuitive.

Would replacing the rotor "windings" with copper wire or bus bar
(easy), and rewinding the stator with bigger wire (hard) have any
chance at all of working together by lowering the leakage inductance
and rotor resistance to allow resonance?

That's my best question; is there any hope at all?

This is a one-off demo, not a production prototype!

Yours,

Doug Goncz
Replikon Research
Falls Church, VA 22044-0394

On Tue, 21 Jun 2005 18:57:47 -0700, DGoncz wrote:

That's my best question; is there any hope at all?

This is a one-off demo, not a production prototype!

Well, let's touch base with reality here.

What do you actually have? A bicycle with a generator?

Let's get to the basics. Don't pull theory on these frat boys,
they'll tear you to ribbons.

What do you have now, and what are you trying to accomplish?

Thanks,
Rich

Sorry to miss your reply, Rich.

There have been a few different configurations on road.

There was a motor, glued to the V in the bottom bracket on the mountain
bike. An EROS bike motor, with an adapter to the custom cogs Jensen
made. And a chain to a right hand crank and cogs, with the pedal
tending to unscrew. And a Bicycle Lighting Systems PAR 35 6VDC light.
This rig didn't work real well, so I made a motor mount, and got a
bigger motor.

The Ametek servo motor is 4" OD and 5" L. See
ftp://users.aol.com/DGoncz for photos of the trapezoidal mount with
hose clamps, low in the V near the bottom bracket. Not bad. Rode up
hill at night with the B.L.S. light.

Then there was the big round disk covering the main triangle. Of 3/4
inch LDF. This allowed for chain drive from the pedals or the rear
wheel. The rear gear on the mountain bike was brazed from a steel BMX
spider and had a bottom bracket lock ring on it. It mounted to the flip
flop hub, relaced to the rim.

With that rig, I added ultracapacitors. Eight PC 2500 2700 F 2.5 V
caps from Maxwell, surplus. And a digital dashboard.

The caps were never used on the recumbent. The Ametek motor mounts
under the seat back bag on the Thunderbolt. The mount was made of
plastic drain pipe. Eventually it became clear that an idler was needed
to keep the chain on the rear cog, which was made from a Big Cheese BMX
chain ring holder, mounted on a mountain bike disc hub, relaced to the
rear rim.

That was the rig in the videos at ftp://users.aol.com/DGoncz. New
Year's Eve. 24 watts of Christmas lights on the bike, driven by the
Ametek and an inverter.

There was also the AC generator, subject of this thread, painstakingly
mounted to the front derailer post. One day, the Ametek drove the
inverter which drove the front motor/generaor in motor mode. It was a
shakedown.

What I am trying to accomplish is to provide all the electrical needs
of an infantry soldier, with reasonable mobility and load carrying
ability, on dirt roads, whether riding or stopped, such that the only
resupply will be ammunition and food. Currently we resupply a lot of
primary and secondary batteries to our infantry. An awful lot. A
mobility and operational capability restricting large quantity, in
fact.

Doug

On Tue, 28 Jun 2005 18:07:21 -0700, DGoncz wrote:

What I am trying to accomplish is to provide all the electrical needs
of an infantry soldier, with reasonable mobility and load carrying
ability, on dirt roads, whether riding or stopped, such that the only
resupply will be ammunition and food. Currently we resupply a lot of
primary and secondary batteries to our infantry. An awful lot. A
mobility and operational capability restricting large quantity, in
fact.

Oh. Now I see why the big secrecy.

Since I'm a pacifist, you may now go masturbate.

Thanks,
Rich

On Wed, 29 Jun 2005 18:14:31 GMT, Rich Grise
wrote:

On Tue, 28 Jun 2005 18:07:21 -0700, DGoncz wrote:

What I am trying to accomplish is to provide all the electrical needs
of an infantry soldier, with reasonable mobility and load carrying
ability, on dirt roads, whether riding or stopped, such that the only
resupply will be ammunition and food. Currently we resupply a lot of
primary and secondary batteries to our infantry. An awful lot. A
mobility and operational capability restricting large quantity, in
fact.

Oh. Now I see why the big secrecy.

Since I'm a pacifist, you may now go masturbate.

Thanks,
Rich

Rich,
DGoncz is a good guy. Helpful if he knows the answer, educational
because he keeps the folks on RCM updated on his experiments. Really
detailed stuff. Your comment was out of line. If you were trying to be
funny you failed.
Eric R Snow

I'm a pacifist, too, Rich.

I can hardly kill a bug.

Doug

I'm a pacifist, too, Rich.

I can hardly kill a bug.

Doug

On Wed, 29 Jun 2005 18:14:31 GMT, Rich Grise
wrote:

On Tue, 28 Jun 2005 18:07:21 -0700, DGoncz wrote:

What I am trying to accomplish is to provide all the electrical needs
of an infantry soldier, with reasonable mobility and load carrying
ability, on dirt roads, whether riding or stopped, such that the only
resupply will be ammunition and food. Currently we resupply a lot of
primary and secondary batteries to our infantry. An awful lot. A
mobility and operational capability restricting large quantity, in
fact.

Oh. Now I see why the big secrecy.

Since I'm a pacifist, you may now go masturbate.

Thanks,
Rich

Masturbate?

Sounds like you are suffering from a deep seated mental illness.

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Thu, 30 Jun 2005 07:59:06 +0000, Gunner wrote:
On Wed, 29 Jun 2005 18:14:31 GMT, Rich Grise
On Tue, 28 Jun 2005 18:07:21 -0700, DGoncz wrote:
What I am trying to accomplish is to provide all the electrical needs
of an infantry soldier, with reasonable mobility and load carrying
ability, on dirt roads, whether riding or stopped, such that the only
resupply will be ammunition and food. Currently we resupply a lot of
primary and secondary batteries to our infantry. An awful lot. A
mobility and operational capability restricting large quantity, in
fact.

Oh. Now I see why the big secrecy.

Since I'm a pacifist, you may now go masturbate.

Masturbate?

Sounds like you are suffering from a deep seated mental illness.

Takes one to know one! ;-P
--
Flap!
The Pig Bladder from Uranus, still waiting for that
hot babe to ask what my favorite planet is. ;-j

On Thu, 30 Jun 2005 18:53:34 GMT, Pig Bladder
wrote:

On Thu, 30 Jun 2005 07:59:06 +0000, Gunner wrote:
On Wed, 29 Jun 2005 18:14:31 GMT, Rich Grise
On Tue, 28 Jun 2005 18:07:21 -0700, DGoncz wrote:
What I am trying to accomplish is to provide all the electrical needs
of an infantry soldier, with reasonable mobility and load carrying
ability, on dirt roads, whether riding or stopped, such that the only
resupply will be ammunition and food. Currently we resupply a lot of
primary and secondary batteries to our infantry. An awful lot. A
mobility and operational capability restricting large quantity, in
fact.

Oh. Now I see why the big secrecy.

Since I'm a pacifist, you may now go masturbate.

Masturbate?

Sounds like you are suffering from a deep seated mental illness.

Takes one to know one! ;-P

Actually, it takes an observer.

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

wrote:
Sorry to miss your reply, Rich.

There have been a few different configurations on road.

There was a motor, glued to the V in the bottom bracket on the mountain
bike. An EROS bike motor, with an adapter to the custom cogs Jensen
made. And a chain to a right hand crank and cogs, with the pedal
tending to unscrew. And a Bicycle Lighting Systems PAR 35 6VDC light.
This rig didn't work real well, so I made a motor mount, and got a
bigger motor.

The Ametek servo motor is 4" OD and 5" L. See
ftp://users.aol.com/DGoncz for photos of the trapezoidal mount with
hose clamps, low in the V near the bottom bracket. Not bad. Rode up
hill at night with the B.L.S. light.

Then there was the big round disk covering the main triangle. Of 3/4
inch LDF. This allowed for chain drive from the pedals or the rear
wheel. The rear gear on the mountain bike was brazed from a steel BMX
spider and had a bottom bracket lock ring on it. It mounted to the flip
flop hub, relaced to the rim.

With that rig, I added ultracapacitors. Eight PC 2500 2700 F 2.5 V
caps from Maxwell, surplus. And a digital dashboard.

The caps were never used on the recumbent. The Ametek motor mounts
under the seat back bag on the Thunderbolt. The mount was made of
plastic drain pipe. Eventually it became clear that an idler was needed
to keep the chain on the rear cog, which was made from a Big Cheese BMX
chain ring holder, mounted on a mountain bike disc hub, relaced to the
rear rim.

That was the rig in the videos at ftp://users.aol.com/DGoncz. New
Year's Eve. 24 watts of Christmas lights on the bike, driven by the
Ametek and an inverter.

There was also the AC generator, subject of this thread, painstakingly
mounted to the front derailer post. One day, the Ametek drove the
inverter which drove the front motor/generaor in motor mode. It was a
shakedown.

If you posted all that in English u might get more feedback.


What I am trying to accomplish is to provide all the electrical needs
of an infantry soldier, with reasonable mobility and load carrying
ability, on dirt roads, whether riding or stopped, such that the only
resupply will be ammunition and food. Currently we resupply a lot of
primary and secondary batteries to our infantry. An awful lot. A
mobility and operational capability restricting large quantity, in
fact.

Doug


I would start at this point if I were you, because I think your idea of
a way to do it is fundamentally flawed.

Using a soldier to manually generate electricity will impose
substantial extra physical demands on him. This means healthy soldiers
will cover less miles, do less work, arrive more tired, and generally
make them an inferior fighting force. Hardly what you want in your
military!

The whole idea with power is to have the power help the user, rather
than the user slave away to produce the power. One helps, the other
hinders.

This issue makes your whole approach a dead duck in most situations. It
may have its apps, but will be deprecated in most situations.

More logical would be a solar panel on the bike. Even supplying endless
batteries is better that pedal power, when you can provide those
supplies.


NT

I believe a bicycle coasting down a hill normally travels faster than a
walking soldier. If generator output allows power capture on coasts,
reducing speed to walking speed, then as far as mobility goes, on dirt
roads, it's a dead heat for speed, with the bicycle/generator out ahead
in terms of independence from supply.

Doug

On Sat, 02 Jul 2005 15:10:26 -0700, bigcat wrote:
....
Using a soldier to manually generate electricity will impose
substantial extra physical demands on him. This means healthy soldiers
will cover less miles, do less work, arrive more tired, and generally
make them an inferior fighting force. Hardly what you want in your
military!
....

Hey! Works for me! ;-P

Cheers!
Rich

On Sat, 02 Jul 2005 17:49:23 -0700, DGoncz wrote:

I believe a bicycle coasting down a hill normally travels faster than a
walking soldier. If generator output allows power capture on coasts,
reducing speed to walking speed, then as far as mobility goes, on dirt
roads, it's a dead heat for speed, with the bicycle/generator out ahead
in terms of independence from supply.

Yabbut, who gets volunteered to push the damn thing back up the hill?

Thanks,
Rich

Yabbut, which is easier, backpacking 1000 feet vertical with 70 pounds
on you, or pedaling a 100 pound bicycle up the equivalent road? I admit
bikes can't go everywhere, but anywhere they go they are more efficient
than porting a load.

Doug

wrote:
I believe a bicycle coasting down a hill normally travels faster than a
walking soldier. If generator output allows power capture on coasts,
reducing speed to walking speed, then as far as mobility goes, on dirt
roads, it's a dead heat for speed, with the bicycle/generator out ahead
in terms of independence from supply.

Doug

If you actually work out how much energy you can capture that way, I
think youll find it disappointing.

NT

wrote:
wrote:
I believe a bicycle coasting down a hill normally travels faster than a
walking soldier. If generator output allows power capture on coasts,
reducing speed to walking speed, then as far as mobility goes, on dirt
roads, it's a dead heat for speed, with the bicycle/generator out ahead
in terms of independence from supply.

Doug

If you actually work out how much energy you can capture that way, I
think youll find it disappointing.

NT

Dear NT,

I have worked it out. I was impressed, not disappointed. I have
actually captured such energy. I was more than impressed, I was
frightened. I had to slam on the brakes before I damaged the wiring and
components with the several hundred watt power surge.

Doug