Winch Experts wanted

In article 405fd00e$1@darkstar, says...
I'm also getting the impression that one can use a much less
powerful electric motor becase the amount of HP getting to the
cable and ending up as effective pull is much higher than
for a traditional fuel motor. I'd like to really know what
a 100 hp electric would do in terms of accelerating a
500 pound glider.

100HP is getting up there. I'm sure it would accelerate a 500lb
glider quite nicely. This is out of my area of expertise, but can
easily be done by somebody with the knowledge of tractive systems.

Thinking more about advantages and disadvantages, electric
shock could be a biggie,

Actually the threat of electrical shock is minimal compared to that
of the mechanical hazards present with rotating machinery.

and I imagine there IS some heat generated.

Heat is not an issue. The efficiencies of modern electric motors will
approach 95%, whereas the efficiency of an internal combustion engine
is on the order of 20-25%.

Wear is likely less of an issue, perhaps
brush changes once in a while. Designing it with spectra
in mind seems a good idea...reduces the weight of line and
thereby the HP requirement. This shifts the expense from the
initial expense instead to ongoing expense (replacing and repairing
expensive rope). I'd favor this. Anything that allows the
same UMPF for less initial investment...

I can't see the first cost of an electrically driven winch being
competitive with an engine driven winch. Where I see the economic
advantages are in the life cycle costs of the winch. An electric
motor, with its one moving part, is very reliable.

Having such good control of the motor seems like it would really
improve efficiency too. Sure sure, expert winch drivers
do great things, but it would be nice to not need "experts"
to do something that should be simple...

This is where I see one of the advantages of electric drive with a
programmable variable speed drive. I take a look at modern chair
lifts found at ski resorts. Multi-speed, multi-stage and operated by
people that, well, lets not go there.

Anyway, I was just kinda thinking out loud, in a written sort of way.


One other possible inefficiency...I wonder how much electric
attenuation occurs over even thick power supply cables.
But I definitely think electric winch is the way to go...

Bill Daniels wrote:

that can be pulled by a mid-size pickup or SUV (under 4000 lbs. total).
Anything larger, or built on a truck is, in my opinion, not
practical
for anything other than primarily fixed site usage.

I've seen a bunch of surplus 150 to 200 hp electric motors
for $3,000 to $5,000. Seems like a very logical choice (much cleaner,
easier to control, not as much fire danger, simple, etc.).
But definitely this is a fixed winch (and how does one get 500 volts and
100 amps for a power supply? At Avenal if it ran
the whole city might go dim The 50 car batteries idea is only
$2,000 to $5,000 but one wonders if this and a generator isn't
Avenal, California, USA
I have seen EV Dragsters with electric forklift motors putting out 500
HP. Can pull a 3000 lb car Down the 1/4 mile in 14 or so sec.
Now where to get the 440 volts dc from

home built up to 70 mph, 50 to 100 mile range, 1000 foot lbs of torque
Lots of info here.
http://groups.yahoo.com/group/EVList/messages/

Before you guys get too far into an electric winch design, look up
"Ultracapacitors". Basically these are huge electrical capacitors that can
charge and discharge at extremely high amperages. Maxwell Technologies in
San Diego that makes the best ones in the world.
http://www.maxwell.com/index.html

Use a small generator set to charge a bank of ultracaps, then dump the
accumulated charge into your 500HP forklift motor.

Bill Daniels




--

------------+
Mark Boyd
Avenal, California, USA

"Mark James Boyd" wrote in message
news:405fd12c$1@darkstar...
LOL. I've never seen as much overengineering anywhere than
on RAS and in the government. Two winches? Does the wind shift
that often? How about one winch, right next to the existing
power lines (at least for the darned prototype)?

You guys crack me up with your "glider winch and power station
industrial complex" designs. If you're that rich, good
for you! ;P


http://www.glidingmagazine.com/Featu...cle.asp?id=293 covers just the
kind of thing you guys are re-inventing. By the way the unit cost them 56000
Euros and that was a year ago, at the time they considered it cheaper than
the alternatives.

www.elektrostartwinde.de has details on commercial availability.

Some details
up to 20kw draw from the 3 phase mains supply
200kw launch power
850 kg max glider weight
1 g initial acceleration
Euro 1.90 per launch including cable, winch and battery replacements
Electronic motor control

There is a fixed multiple drum electric winch somewhere in Germany too.

Ian

tango4 wrote:
"Mark James Boyd" wrote in message
that often? How about one winch, right next to the existing
power lines (at least for the darned prototype)?

You guys crack me up with your "glider winch and power station
industrial complex" designs. If you're that rich, good
for you! ;P

http://www.glidingmagazine.com/Featu...cle.asp?id=293 covers just the
kind of thing you guys are re-inventing. By the way the unit cost them 56000
Euros and that was a year ago, at the time they considered it cheaper than
the alternatives.

Some details
up to 20kw draw from the 3 phase mains supply
200kw launch power
850 kg max glider weight
1 g initial acceleration
Euro 1.90 per launch including cable, winch and battery replacements
Electronic motor control

Just to be clear, I personally have no interest in winching a 850kg
glider, laying 5000 meters of copper cable, or paying for a winch
AND a spanking new semi truck (all mentioned in the glidingmagazine
article).

I'm interested in about 1/4 of that weight glider (226 kg),
a few hundred feet of copper power cable, a 4000# total weight towed
as a trailer behind a truck, and spectra rope that doesn't weigh 300# or
lash around and leave pieces of metal in the
winch driver when it breaks.

If an electric motor of 100hp like the one at
http://www.electricmotorwarehouse.co...sion_proof.htm
for about $5,000 and 2,000 pounds can do the trick, I'm guessing
the other $60,000 (US) would cover the trailer and copper wire and
spectra and knicknacks with enough left over to
make four spare mini-winches and still buy a used AC-4c Russia :P

That's a big IF. I still don't know the apples to oranges
electric to fuel based engine UMPH...(tension that actually gets to
the glider). Is 100hp enough? If boat engines or car conversions are
any indication, electrics are 3 times as efficient as gas motors
in terms of HP actually delivered. So maybe an electric "100 hp"
winch is equivalent to 300hp of gas engine? Also, do the electric
motors really put out the same UMPH at lower RPM? I dunno...

I also don't put too much credibility to european pricing.
I remember the metal price tags on the trees in Germany
(in case you hit one and killed it you'd have to pay for it.)
$12,000 for a TREE?! Those Germans seemed to heap on a lot
of expensive fertilizer... ;P I'm all about clean air,
sunshine, some water, and soil. Besides, if Marc will
do all the labor for free, we can avoid the 100% to 200% retail
"markup," right?
--

------------+
Mark Boyd
Avenal, California, USA

"Todd Pattist" wrote in message
...
"Bill Daniels" wrote:

Before you guys get too far into an electric winch design, look up
"Ultracapacitors". Basically these are huge electrical capacitors that
can
charge and discharge at extremely high amperages.

When we used high energy capacitors on a research project,
we kept them in a concrete block room with steel airlock
doors that sealed the room automatically while they were
charging. When the dielectric broke down on one capacitor,
the explosion threw steel shards through a nearby table. I
have no idea if this applies to all high energy capacitors,
but caution and investigation are appropriate.
Todd Pattist - "WH" Ventus C
(Remove DONTSPAMME from address to email reply.)

I hadn't thought of that. With 3.6M joules stored, that would make a really
big ZAP if it shorted. I do know that ultracaps are being used on electric
busses to recover braking energy from the wheel motors. They charge and
discharge far more efficiently than batteries. Maxwell Technologies makes a
pretty good case for their product.

The problem I see is cost. It would require something like 600 2700 Farad
ultracaps to store 3.6M Joules. You save some of that by using a much
smaller engine in the genset that runs continuously to recharge the ultracap
bank between launches.

Safety might still be an issue just because there is so much energy stored
whether batteries or ultracaps. If the winch balks and needs repair after
the batteries or ultracaps are charged, you'd have to be damn careful what
you touched.

Bill Daniels

Dave,
Excellent suggestion and - of course - it has been done already. In
fact it was around 1985 or so when I flew in France each spring for a
couple of weeks at wonderful St. Remy de Provence with about half the
launches done off a hydrostatic winch. It was arranged exactly as you
propose with a motor in each (large) reel, a dedicated diesel engine
driving the pump, all on a truck chassis. Very smooth and powerful
acceleration and launch altitudes of 400 m or 1,200 feet. Wonder if
they still run that winch, anybody out there has an idea?

Herbert


Has anyone considered the use of 'Hydrostatic Pumps'

Using the main engine to drive a hydraulic compressing
pump, as used on mechanical diggers etc, a hydrostatic
pump on each individual drum would provide the power
to launch the glider.

It would remove the need for complex mechanics and
by a simple system of taps could drive any one of a
number of individual drums.

Using deep sided drums without pay on gear would reduce
build costs and time.

Building the winch on a trailer would be simple, mobile
and may be cheaper than using complex mechanical drives.
It would also be simple to maintain. I understand modern
pumps can be programmed and controlled electronically.


The main pumps can provide sufficient power as can
be seen on mechanical diggers, but they are only pumping
us a telescopic ram. I believe they are used on slow
moving agricultural equipment to provide drive to the
main wheels.

The question is could the pumps provide the power and
speed to drive a drum for several minutes to enable
a glider to be launched.

Similar pumps can be seen at

http://www.casappa.com/

Although I am sure they will be available throughout
the world.


Dave

In article ,
says...

"Mark James Boyd" wrote in message
news:405fd12c$1@darkstar...
LOL. I've never seen as much overengineering anywhere than
on RAS and in the government. Two winches? Does the wind shift
that often? How about one winch, right next to the existing
power lines (at least for the darned prototype)?

You guys crack me up with your "glider winch and power station
industrial complex" designs. If you're that rich, good
for you! ;P


http://www.glidingmagazine.com/Featu...cle.asp?id=293 covers just the
kind of thing you guys are re-inventing. By the way the unit cost them 56000
Euros and that was a year ago, at the time they considered it cheaper than
the alternatives.

www.elektrostartwinde.de has details on commercial availability.

Some details
up to 20kw draw from the 3 phase mains supply
200kw launch power
850 kg max glider weight
1 g initial acceleration
Euro 1.90 per launch including cable, winch and battery replacements
Electronic motor control

There is a fixed multiple drum electric winch somewhere in Germany too.

Ian



Thanks for the link. A very nicely done installation, quite
professional.

I knew that my idea was not original enough for someone not to have
done it. It appears that one of the features liked most is the
electronic control of the motor. That was the point I was trying to
make. Modern electronic control of an electric motor just make so
much sense.

Some of the units I need conversions for especially a "daN", I know,
read assume, that it is a Newton but am unfamiliar with the prefix
"da"). There has been a big change in SI units since I was in college
and we insular Yankees haven't done a good job of keeping up.

Thanks again.

In article 405fee2c$1@darkstar, says...
tango4 wrote:
"Mark James Boyd" wrote in message
that often? How about one winch, right next to the existing
power lines (at least for the darned prototype)?

You guys crack me up with your "glider winch and power station
industrial complex" designs. If you're that rich, good
for you! ;P

http://www.glidingmagazine.com/Featu...cle.asp?id=293 covers just the
kind of thing you guys are re-inventing. By the way the unit cost them 56000
Euros and that was a year ago, at the time they considered it cheaper than
the alternatives.

Some details
up to 20kw draw from the 3 phase mains supply
200kw launch power
850 kg max glider weight
1 g initial acceleration
Euro 1.90 per launch including cable, winch and battery replacements
Electronic motor control

Just to be clear, I personally have no interest in winching a 850kg
glider, laying 5000 meters of copper cable, or paying for a winch
AND a spanking new semi truck (all mentioned in the glidingmagazine
article).

I'm interested in about 1/4 of that weight glider (226 kg),
a few hundred feet of copper power cable, a 4000# total weight towed
as a trailer behind a truck, and spectra rope that doesn't weigh 300# or
lash around and leave pieces of metal in the
winch driver when it breaks.

If an electric motor of 100hp like the one at
http://www.electricmotorwarehouse.co...sion_proof.htm
for about $5,000 and 2,000 pounds can do the trick, I'm guessing
the other $60,000 (US) would cover the trailer and copper wire and
spectra and knicknacks with enough left over to
make four spare mini-winches and still buy a used AC-4c Russia :P

That's a big IF. I still don't know the apples to oranges
electric to fuel based engine UMPH...(tension that actually gets to
the glider). Is 100hp enough? If boat engines or car conversions are
any indication, electrics are 3 times as efficient as gas motors
in terms of HP actually delivered. So maybe an electric "100 hp"
winch is equivalent to 300hp of gas engine? Also, do the electric
motors really put out the same UMPH at lower RPM? I dunno...

Electric motors make maximum torque at "stall". This is just what is
wanted.

I also don't put too much credibility to european pricing.
I remember the metal price tags on the trees in Germany
(in case you hit one and killed it you'd have to pay for it.)
$12,000 for a TREE?! Those Germans seemed to heap on a lot
of expensive fertilizer... ;P I'm all about clean air,
sunshine, some water, and soil. Besides, if Marc will
do all the labor for free, we can avoid the 100% to 200% retail
"markup," right?
--

------------+
Mark Boyd
Avenal, California, USA

"Littleboy" wrote in message
ews.com...
In article ,
says...

"Mark James Boyd" wrote in message
news:405fd12c$1@darkstar...
LOL. I've never seen as much overengineering anywhere than
on RAS and in the government. Two winches? Does the wind shift
that often? How about one winch, right next to the existing
power lines (at least for the darned prototype)?

You guys crack me up with your "glider winch and power station
industrial complex" designs. If you're that rich, good
for you! ;P


http://www.glidingmagazine.com/Featu...cle.asp?id=293 covers just the
kind of thing you guys are re-inventing. By the way the unit cost them
56000
Euros and that was a year ago, at the time they considered it cheaper
than
the alternatives.

www.elektrostartwinde.de has details on commercial availability.

Some details
up to 20kw draw from the 3 phase mains supply
200kw launch power
850 kg max glider weight
1 g initial acceleration
Euro 1.90 per launch including cable, winch and battery replacements
Electronic motor control

There is a fixed multiple drum electric winch somewhere in Germany too.

Ian



Thanks for the link. A very nicely done installation, quite
professional.

I knew that my idea was not original enough for someone not to have
done it. It appears that one of the features liked most is the
electronic control of the motor. That was the point I was trying to
make. Modern electronic control of an electric motor just make so
much sense.

Some of the units I need conversions for especially a "daN", I know,
read assume, that it is a Newton but am unfamiliar with the prefix
"da"). There has been a big change in SI units since I was in college
and we insular Yankees haven't done a good job of keeping up.

Thanks again.

That confused me for a while too. daN = DecaNewton. 1 Newton x 10.

Do us a favor and price out the electronic controls. When I did it, the
prices were astronomical but then, I'm not sure I was looking at the right
stuff. It seems that the "elektrostartwinde" folks used variable frequency
induction motors. That seems pretty sophisticated to me.

Bill Daniels

In article ,
says...

"Littleboy" wrote in message
ews.com...
In article ,
says...

"Mark James Boyd" wrote in message
news:405fd12c$1@darkstar...
LOL. I've never seen as much overengineering anywhere than
on RAS and in the government. Two winches? Does the wind shift
that often? How about one winch, right next to the existing
power lines (at least for the darned prototype)?

You guys crack me up with your "glider winch and power station
industrial complex" designs. If you're that rich, good
for you! ;P


http://www.glidingmagazine.com/Featu...cle.asp?id=293 covers just the
kind of thing you guys are re-inventing. By the way the unit cost them
56000
Euros and that was a year ago, at the time they considered it cheaper
than
the alternatives.

www.elektrostartwinde.de has details on commercial availability.

Some details
up to 20kw draw from the 3 phase mains supply
200kw launch power
850 kg max glider weight
1 g initial acceleration
Euro 1.90 per launch including cable, winch and battery replacements
Electronic motor control

There is a fixed multiple drum electric winch somewhere in Germany too.

Ian



Thanks for the link. A very nicely done installation, quite
professional.

I knew that my idea was not original enough for someone not to have
done it. It appears that one of the features liked most is the
electronic control of the motor. That was the point I was trying to
make. Modern electronic control of an electric motor just make so
much sense.

Some of the units I need conversions for especially a "daN", I know,
read assume, that it is a Newton but am unfamiliar with the prefix
"da"). There has been a big change in SI units since I was in college
and we insular Yankees haven't done a good job of keeping up.

Thanks again.

That confused me for a while too. daN = DecaNewton. 1 Newton x 10.

Do us a favor and price out the electronic controls. When I did it, the
prices were astronomical but then, I'm not sure I was looking at the right
stuff. It seems that the "elektrostartwinde" folks used variable frequency
induction motors. That seems pretty sophisticated to me.

Bill Daniels


The motors will be pretty much a standard ac induction motor. There
are motors for "inverter duty". Not sure of adder for this, but I
know that we don't make it a standard to specify inverter duty motors
when coupled to a variable frequency drive.

Actually, variable frequency drives (VFD) have made everyone's lives
much simpler. 15 years ago it VFDs were considered to be very
sophisticated, but today they're all over the place. In many
applications, if I don't see VFDs specified, I am forced to question
the overall quality of the design.

I will get a price for you as soon as I can scare up my favorite
sales engineer here.

Savhydro (the manufacturer of this type of winch) has gone out of business.
We had such a winch in La Motte, too but never succeeded to get it back to
work when the diesel engine "exploded" because no backup from the
manufacturer anymore. Pitty though.

--
Bert Willing

ASW20 "TW"


"Herbert Kilian" a écrit dans le message de
m...
Dave,
Excellent suggestion and - of course - it has been done already. In
fact it was around 1985 or so when I flew in France each spring for a
couple of weeks at wonderful St. Remy de Provence with about half the
launches done off a hydrostatic winch. It was arranged exactly as you
propose with a motor in each (large) reel, a dedicated diesel engine
driving the pump, all on a truck chassis. Very smooth and powerful
acceleration and launch altitudes of 400 m or 1,200 feet. Wonder if
they still run that winch, anybody out there has an idea?

Herbert


Has anyone considered the use of 'Hydrostatic Pumps'

Using the main engine to drive a hydraulic compressing
pump, as used on mechanical diggers etc, a hydrostatic
pump on each individual drum would provide the power
to launch the glider.

It would remove the need for complex mechanics and
by a simple system of taps could drive any one of a
number of individual drums.

Using deep sided drums without pay on gear would reduce
build costs and time.

Building the winch on a trailer would be simple, mobile
and may be cheaper than using complex mechanical drives.
It would also be simple to maintain. I understand modern
pumps can be programmed and controlled electronically.


The main pumps can provide sufficient power as can
be seen on mechanical diggers, but they are only pumping
us a telescopic ram. I believe they are used on slow
moving agricultural equipment to provide drive to the
main wheels.

The question is could the pumps provide the power and
speed to drive a drum for several minutes to enable
a glider to be launched.

Similar pumps can be seen at

http://www.casappa.com/

Although I am sure they will be available throughout
the world.


Dave