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• Jason, The number of windings determines the voltage level. The size of the windings determines the ampacity...current. The speed or RPMs determine the
Message 1 of 24 , Aug 3, 2006
View Source
Jason,

The number of windings determines the voltage level. The size of
the windings determines the ampacity...current. The speed or
RPMs determine the frequency of the electrical voltage pulse train.

Hope that helps clarify things for you.

Regards,

Lawrence

--- In axialflux@yahoogroups.com, "Jason MeGahee" <jmegahee@...>
wrote:
>
> Hi.
>
> I am working on a very different type of wind turbine, i.e. it is
not
> a traditional horizontal axis or any version of the typical vertical
> axis types. I don't want to go into anymore than that until I have
my
> prototype built, tested, and verifible results ready.
>
> But here is what I am trying to understand. I will be utilizing an
> axial flux alternator design but my design may experience higher
rpm's
> than most people using this design.
> I would like to understand the relationship between (1) number of
> windings, (2) wire gauge, and (3) rpm.
>
> For instance, let's say first scenario is 50 turns of 14 awg and
> spinning at 1000 rpm. If the rpm is doubled or tripled, does the
> voltage increase or the amps? How about if everything is the same
> except more turns on the windings or less? And what if the wire size
>
> Any help with understanding these parameters or how to fine tune
these
> parameters after initial testing will be appreciated.
>
> Thanks,
> Jason
>
• And the voltage. The voltage induced per turn is flux - magnetic field strength and rate at which you cut the lines. So speed and magnet strength directly
Message 1 of 24 , Aug 3, 2006
View Source
And the voltage.
The voltage induced per turn is
flux - magnetic field strength and
rate at which you cut the lines.
So speed and magnet strength directly equate to emf produced.

Kirk

Lawrence Rayburn <lawrencerayburn@...> wrote:
Jason,

The number of windings determines the voltage level. The size of
the windings determines the ampacity...current. The speed or
RPMs determine the frequency of the electrical voltage pulse train.

Hope that helps clarify things for you.

Regards,

Lawrence

--- In axialflux@yahoogroups.com, "Jason MeGahee"
wrote:
>
> Hi.
>
> I am working on a very different type of wind turbine, i.e. it is
not
> a traditional horizontal axis or any version of the typical vertical
> axis types. I don't want to go into anymore than that until I have
my
> prototype built, tested, and verifible results ready.
>
> But here is what I am trying to understand. I will be utilizing an
> axial flux alternator design but my design may experience higher
rpm's
> than most people using this design.
> I would like to understand the relationship between (1) number of
> windings, (2) wire gauge, and (3) rpm.
>
> For instance, let's say first scenario is 50 turns of 14 awg and
> spinning at 1000 rpm. If the rpm is doubled or tripled, does the
> voltage increase or the amps? How about if everything is the same
> except more turns on the windings or less? And what if the wire size
>
> Any help with understanding these parameters or how to fine tune
these
> parameters after initial testing will be appreciated.
>
> Thanks,
> Jason
>

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• Hi, Sorry for leaving the entire thread in this post but for some reason my computer will not let me edit it. I m learning and just want to understand: It s
Message 1 of 24 , Aug 3, 2006
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Hi,

Sorry for leaving the entire thread in this post but for some reason my computer will not let me edit it.

I'm learning and just want to understand: It's the number of windings that determine voltage, but rate of cutting magnetic lines and also strength of magnetic feild can affect voltage too?

If I were making a generator, I should plan to experiment as a means of determining a final configuration as opposed to following a formula?

Thanks,
Dan

----- Original Message -----
Sent: Thursday, August 03, 2006 12:24 PM
Subject: Re: [axialflux] Re: Relationship parameters

And the voltage.
The voltage induced per turn is
flux - magnetic field strength and
rate at which you cut the lines.
So speed and magnet strength directly equate to emf produced.

Kirk

Lawrence Rayburn <lawrencerayburn@ yahoo.com> wrote:
Jason,

The number of windings determines the voltage level. The size of
the windings determines the ampacity...current. The speed or
RPMs determine the frequency of the electrical voltage pulse train.

Hope that helps clarify things for you.

Regards,

Lawrence

--- In axialflux@yahoogrou ps.com, "Jason MeGahee"
wrote:
>
> Hi.
>
> I am working on a very different type of wind turbine, i.e. it is
not
> a traditional horizontal axis or any version of the typical vertical
> axis types. I don't want to go into anymore than that until I have
my
> prototype built, tested, and verifible results ready.
>
> But here is what I am trying to understand. I will be utilizing an
> axial flux alternator design but my design may experience higher
rpm's
> than most people using this design.
> I would like to understand the relationship between (1) number of
> windings, (2) wire gauge, and (3) rpm.
>
> For instance, let's say first scenario is 50 turns of 14 awg and
> spinning at 1000 rpm. If the rpm is doubled or tripled, does the
> voltage increase or the amps? How about if everything is the same
> except more turns on the windings or less? And what if the wire size
>
> Any help with understanding these parameters or how to fine tune
these
> parameters after initial testing will be appreciated.
>
> Thanks,
> Jason
>

Related Link: http://www.green- trust.org/ 2006/06/axial- flux-permanent- magnet-alternato r.html
Post message: axialflux@yahoogrou ps.com
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• Yes. You get an amount based on field strength and rate and that amount is then multiplied by the number of turns. In the real world the flux will have a bit
Message 1 of 24 , Aug 3, 2006
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Yes. You get an amount based on field strength and rate and that amount is then multiplied by the number of turns. In the real world the flux will have a bit of non uniformity but the rpm is the same for all. Increasing speed or increasing field strength increases emf induced in each turn.

Kirk

Dan Clarke <clarke@...> wrote:
Hi,

Sorry for leaving the entire thread in this post but for some reason my computer will not let me edit it.

I'm learning and just want to understand: It's the number of windings that determine voltage, but rate of cutting magnetic lines and also strength of magnetic feild can affect voltage too?

If I were making a generator, I should plan to experiment as a means of determining a final configuration as opposed to following a formula?

Thanks,
Dan

----- Original Message -----
Sent: Thursday, August 03, 2006 12:24 PM
Subject: Re: [axialflux] Re: Relationship parameters

And the voltage.
The voltage induced per turn is
flux - magnetic field strength and
rate at which you cut the lines.
So speed and magnet strength directly equate to emf produced.

Kirk

Lawrence Rayburn <lawrencerayburn@ yahoo.com> wrote:
Jason,

The number of windings determines the voltage level. The size of
the windings determines the ampacity...current. The speed or
RPMs determine the frequency of the electrical voltage pulse train.

Hope that helps clarify things for you.

Regards,

Lawrence

--- In axialflux@yahoogrou ps.com, "Jason MeGahee"
wrote:
>
> Hi.
>
> I am working on a very different type of wind turbine, i.e. it is
not
> a traditional horizontal axis or any version of the typical vertical
> axis types. I don't want to go into anymore than that until I have
my
> prototype built, tested, and verifible results ready.
>
> But here is what I am trying to understand. I will be utilizing an
> axial flux alternator design but my design may experience higher
rpm's
> than most people using this design.
> I would like to understand the relationship between (1) number of
> windings, (2) wire gauge, and (3) rpm.
>
> For instance, let's say first scenario is 50 turns of 14 awg and
> spinning at 1000 rpm. If the rpm is doubled or tripled, does the
> voltage increase or the amps? How about if everything is the same
> except more turns on the windings or less? And what if the wire size
>
> Any help with understanding these parameters or how to fine tune
these
> parameters after initial testing will be appreciated.
>
> Thanks,
> Jason
>

Related Link: http://www.green- trust.org/ 2006/06/axial- flux-permanent- magnet-alternato r.html
Post message: axialflux@yahoogrou ps.com
Subscribe: axialflux-subscribe @yahoogroups. com
Unsubscribe: axialflux-unsubscri be@yahoogroups. com
List owner: axialflux-owner@ yahoogroups. com

<*> To visit your group on the web, go to:
http://groups. yahoo.com/ group/axialflux/

<*> To unsubscribe from this group, send an email to:
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Do you Yahoo!?
Get on board. You're invited to try the new Yahoo! Mail Beta.

• http://www.tinaja.com/glib/muse117.pdf A nice resource Kirk ... See the all-new, redesigned Yahoo.com. Check it out.
Message 1 of 24 , Aug 4, 2006
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A nice resource

Kirk

See the all-new, redesigned Yahoo.com. Check it out.

• But not very related to an axial flux alternator. Homopolar generators are a completely different animal. Dc outputs and requiring brushes. Steve Spence
Message 1 of 24 , Aug 7, 2006
View Source

But not very related to an axial flux alternator. Homopolar generators are a completely different animal. Dc outputs and requiring brushes.

Steve Spence

Director, Green Trust

http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Kirk McLoren
Sent: Friday, August 04, 2006 9:46 PM
To: axialflux@yahoogroups.com
Subject: [axialflux] relationship between flux and speed in a generator

A nice resource

Kirk

• That (homopolar) discussion starts on page 3. Did you skip pages 1 and 2? It was remarked earlier that one of the users here didnt know velocity was important
Message 1 of 24 , Aug 7, 2006
View Source
That (homopolar) discussion starts on page 3. Did you skip pages 1 and 2?
It was remarked earlier that one of the users here didnt know velocity was important - thus page 2.
Kirk
Steve Spence <sspence@...> wrote:
But not very related to an axial flux alternator. Homopolar generators are a completely different animal. Dc outputs and requiring brushes.

Steve Spence
Director, Green Trust
http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Kirk McLoren
Sent: Friday, August 04, 2006 9:46 PM
To: axialflux@yahoogroups.com
Subject: [axialflux] relationship between flux and speed in a generator

A nice resource

Kirk

Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1Â˘/min.

• I didnâ€™t skip it, I just misunderstood the reason for the reference. I find Lancaster to be a crusty old dude. We butt heads quite often. Used to love his
Message 1 of 24 , Aug 7, 2006
View Source

I didn’t skip it, I just misunderstood the reason for the reference. I find Lancaster to be a crusty old dude. We butt heads quite often. Used to love his electronics articles.

Steve Spence

Director, Green Trust

http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Kirk McLoren
Sent: Monday, August 07, 2006 11:59 AM
To: axialflux@yahoogroups.com
Subject: RE: [axialflux] relationship between flux and speed in a generator

That (homopolar) discussion starts on page 3. Did you skip pages 1 and 2?

It was remarked earlier that one of the users here didnt know velocity was important - thus page 2.
Kirk
Steve Spence <sspence@green- trust.org> wrote:

But not very related to an axial flux alternator. Homopolar generators are a completely different animal. Dc outputs and requiring brushes.

Steve Spence

Director, Green Trust

http://www.green- trust.org

From: axialflux@yahoogrou ps.com [mailto: axialflux@yahoogrou ps.com ] On Behalf Of Kirk McLoren
Sent: Friday, August 04, 2006 9:46 PM
To: axialflux@yahoogrou ps.com
Subject: [axialflux] relationship between flux and speed in a generator

A nice resource

Kirk

Â

Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1Â˘/min.

• Didnt know that. He tends to be technically correct. Pretty good author though I dont see much anymore - but then the younger guys seem more and more to skip
Message 1 of 24 , Aug 7, 2006
View Source
Didnt know that. He tends to be technically correct.
Pretty good author though I dont see much anymore - but then the younger guys seem more and more to skip science class. Most of the publications are no more. 73 is gone and I knew an article was in the pipeline re rhombics at 2 meters. Now I will never get to read it. :(
So what are you and Don growling about if I may ask.

Kirk

Steve Spence <sspence@...> wrote:
I didnÂ’t skip it, I just misunderstood the reason for the reference. I find Lancaster to be a crusty old dude. We butt heads quite often. Used to love his electronics articles.

Steve Spence
Director, Green Trust
http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Kirk McLoren
Sent: Monday, August 07, 2006 11:59 AM
To: axialflux@yahoogroups.com
Subject: RE: [axialflux] relationship between flux and speed in a generator

That (homopolar) discussion starts on page 3. Did you skip pages 1 and 2?
It was remarked earlier that one of the users here didnt know velocity was important - thus page 2.
Kirk
Steve Spence <sspence@green- trust.org> wrote:
But not very related to an axial flux alternator. Homopolar generators are a completely different animal. Dc outputs and requiring brushes.

Steve Spence
Director, Green Trust
http://www.green- trust.org

From: axialflux@yahoogrou ps.com [mailto: axialflux@yahoogrou ps.com ] On Behalf Of Kirk McLoren
Sent: Friday, August 04, 2006 9:46 PM
To: axialflux@yahoogrou ps.com
Subject: [axialflux] relationship between flux and speed in a generator

A nice resource

Kirk

Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1Â˘/min.

How low will we go? Check out Yahoo! MessengerÂ’s low PC-to-Phone call rates.
• Mostly semantics. He â€śparticipatesâ€ť a lot on Usenet, where someone will ask a question, and he will just post a URL as his â€śanswerâ€ť, usually
Message 1 of 24 , Aug 7, 2006
View Source

Mostly semantics. He “participates” a lot on Usenet, where someone will ask a question, and he will just post a URL as his “answer”, usually http://www.tinaja.com/glib/energfun.pdf, which, although a good page, is unrelated to the requestor’s specific question. He also finds fault from a theory standpoint with our actual performance data on subjects he has never played with. Apparently he thinks since he is genius level on some subjects, it makes him master of all ;-) I still have a lot of respect for him though. He and Nick Pine are diligent about making sure folks get their units correct, and that is important. They just need to learn to not kill the patient while hitting them over the head with factual corrections <grin>.

Steve Spence

Director, Green Trust

http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Kirk McLoren
Sent: Monday, August 07, 2006 1:00 PM
To: axialflux@yahoogroups.com
Subject: RE: [axialflux] relationship between flux and speed in a generator

Didnt know that. He tends to be technically correct.

Pretty good author though I dont see much anymore - but then the younger guys seem more and more to skip science class. Most of the publications are no more. 73 is gone and I knew an article was in the pipeline re rhombics at 2 meters. Now I will never get to read it. :(

So what are you and Don growling about if I may ask.

Kirk

Steve Spence <sspence@green- trust.org> wrote:

I didn’t skip it, I just misunderstood the reason for the reference. I find Lancaster to be a crusty old dude. We butt heads quite often. Used to love his electronics articles.

Steve Spence

Director, Green Trust

http://www.green- trust.org

From: axialflux@yahoogrou ps.com [mailto: axialflux@yahoogrou ps.com ] On Behalf Of Kirk McLoren
Sent: Monday, August 07, 2006 11:59 AM
To: axialflux@yahoogrou ps.com
Subject: RE: [axialflux] relationship between flux and speed in a generator

That (homopolar) discussion starts on page 3. Did you skip pages 1 and 2?

It was remarked earlier that one of the users here didnt know velocity was important - thus page 2.
Kirk
Steve Spence <sspence@green- trust.org> wrote:

But not very related to an axial flux alternator. Homopolar generators are a completely different animal. Dc outputs and requiring brushes.

Steve Spence

Director, Green Trust

http://www.green- trust.org

From: axialflux@yahoogrou ps.com [mailto: axialflux@yahoogrou ps.com ] On Behalf Of Kirk McLoren
Sent: Friday, August 04, 2006 9:46 PM
To: axialflux@yahoogrou ps.com
Subject: [axialflux] relationship between flux and speed in a generator

A nice resource

Kirk

Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1Â˘/min.

Â

• He probably has a mild case of burnout. Or not so mild. Havent talked to him in years. I see he has some misinfo re ethanol. By and large he has some good
Message 1 of 24 , Aug 7, 2006
View Source
He probably has a mild case of burnout. Or not so mild. Havent talked to him in years.
I see he has some misinfo re ethanol.
By and large he has some good articles though.

Kirk

Steve Spence <sspence@...> wrote:
Mostly semantics. He Â“participatesÂ” a lot on Usenet, where someone will ask a question, and he will just post a URL as his Â“answerÂ”, usually http://www.tinaja.com/glib/energfun.pdf, which, although a good page, is unrelated to the requestorÂ’s specific question. He also finds fault from a theory standpoint with our actual performance data on subjects he has never played with. Apparently he thinks since he is genius level on some subjects, it makes him master of all ;-) I still have a lot of respect for him though. He and Nick Pine are diligent about making sure folks get their units correct, and that is important. They just need to learn to not kill the patient while hitting them over the head with factual corrections <grin>.

Steve Spence
Director, Green Trust
http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Kirk McLoren
Sent: Monday, August 07, 2006 1:00 PM
To: axialflux@yahoogroups.com
Subject: RE: [axialflux] relationship between flux and speed in a generator

Didnt know that. He tends to be technically correct.
Pretty good author though I dont see much anymore - but then the younger guys seem more and more to skip science class. Most of the publications are no more. 73 is gone and I knew an article was in the pipeline re rhombics at 2 meters. Now I will never get to read it. :(
So what are you and Don growling about if I may ask.

Kirk

Steve Spence <sspence@green- trust.org> wrote:
I didnÂ’t skip it, I just misunderstood the reason for the reference. I find Lancaster to be a crusty old dude. We butt heads quite often. Used to love his electronics articles.

Steve Spence
Director, Green Trust
http://www.green- trust.org

From: axialflux@yahoogrou ps.com [mailto: axialflux@yahoogrou ps.com ] On Behalf Of Kirk McLoren
Sent: Monday, August 07, 2006 11:59 AM
To: axialflux@yahoogrou ps.com
Subject: RE: [axialflux] relationship between flux and speed in a generator

That (homopolar) discussion starts on page 3. Did you skip pages 1 and 2?
It was remarked earlier that one of the users here didnt know velocity was important - thus page 2.
Kirk
Steve Spence <sspence@green- trust.org> wrote:
But not very related to an axial flux alternator. Homopolar generators are a completely different animal. Dc outputs and requiring brushes.

Steve Spence
Director, Green Trust
http://www.green- trust.org

From: axialflux@yahoogrou ps.com [mailto: axialflux@yahoogrou ps.com ] On Behalf Of Kirk McLoren
Sent: Friday, August 04, 2006 9:46 PM
To: axialflux@yahoogrou ps.com
Subject: [axialflux] relationship between flux and speed in a generator

A nice resource

Kirk

Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1Â˘/min.

Do you Yahoo!?
Next-gen email? Have it all with the all-new Yahoo! Mail Beta.
• Steve, An axial flux generator can be homopolar and will output only DC, if you spin the central disk with magnets mounted on both sides of the disk with the
Message 1 of 24 , Aug 8, 2006
View Source
Steve,

An axial flux generator can be homopolar and will output only DC,
if you spin the central disk with magnets mounted on both sides
of the disk with the same pole facing outward, with coils mounted
on the ends on similar sized disks that are fixed, you don't have
any brushes or slip rings.

It's all in the design. A homopolar axial flux generator is one of
the most efficient designs available for a variable motive power
supply...such as wind, a small seasonal stream, etc.

I personally don't like alternators even with rectifiers to
convert to DC for battery storage because they are not as
efficient as simple homopolar generators at producing DC
power from a variable speed motive source.

Regards,

Lawrence

--- In axialflux@yahoogroups.com, "Steve Spence" <sspence@...> wrote:
>
> But not very related to an axial flux alternator. Homopolar
generators are a
> completely different animal. Dc outputs and requiring brushes.
>
>
>
> Steve Spence
>
> Director, Green Trust
>
> http://www.green-trust.org
>
> _____
>
> From: axialflux@yahoogroups.com [mailto:axialflux@yahoogroups.com]
On Behalf
> Of Kirk McLoren
> Sent: Friday, August 04, 2006 9:46 PM
> To: axialflux@yahoogroups.com
> Subject: [axialflux] relationship between flux and speed in a
generator
>
>
>
> http://www.tinaja. <http://www.tinaja.com/glib/muse117.pdf>
> com/glib/muse117.pdf
>
>
>
> A nice resource
>
>
>
> Kirk
>
• Talk to me more offline on this homopolar axial flux generator design so that I can decide whether to cover it on this board. It sounds interesting. This is
Message 1 of 24 , Aug 8, 2006
View Source

Talk to me more offline on this homopolar axial flux generator design so that I can decide whether to cover it on this board. It sounds interesting.

This is the only reference I have read on this subject, and it didn’t look like what you are describing.

http://en.wikipedia.org/wiki/Homopolar_generator

Steve Spence

Director, Green Trust

http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Lawrence Rayburn
Sent: Tuesday, August 08, 2006 10:12 AM
To: axialflux@yahoogroups.com
Subject: [axialflux] Re:homopolar generator vs axial flux alternator

Steve,

An axial flux generator can be homopolar and will output only DC,
if you spin the central disk with magnets mounted on both sides
of the disk with the same pole facing outward, with coils mounted
on the ends on similar sized disks that are fixed, you don't have
any brushes or slip rings.

It's all in the design. A homopolar axial flux generator is one of
the most efficient designs available for a variable motive power
supply...such as wind, a small seasonal stream, etc.

I personally don't like alternators even with rectifiers to
convert to DC for battery storage because they are not as
efficient as simple homopolar generators at producing DC
power from a variable speed motive source.

Regards,

Lawrence

--- In axialflux@yahoogrou ps.com, "Steve Spence" <sspence@... > wrote:

>
> But not very related to an axial flux alternator. Homopolar
generators are a
> completely different animal. Dc outputs and requiring brushes.
>
>
>
> Steve Spence
>
> Director, Green Trust
>
> http://www.green- trust.org
>
> _____
>
> From: axialflux@yahoogrou ps.com
[mailto:axialflux@yahoogrou ps.com]
On Behalf
> Of Kirk McLoren
> Sent: Friday, August 04, 2006 9:46 PM
> To: axialflux@yahoogrou ps.com
> Subject: [axialflux] relationship between flux and speed in a
generator
>
>
>
> http://www.tinaja. <
href="http://www.tinaja.com/glib/muse117.pdf">http://www.tinaja. com/glib/ muse117.pdf>
> com/glib/muse117. pdf
>
>
>
> A nice resource
>
>
>
> Kirk
>

• Hi, I m new to this stuff. Is there a website where the subject is discussed in a basic way? I d like to catch up. Thanks, Dan ... From: Lawrence Rayburn To:
Message 1 of 24 , Aug 8, 2006
View Source
Hi,

I'm new to this stuff.
Is there a website where the subject is discussed in a basic way? I'd like to catch up.

Thanks,
Dan
----- Original Message -----
Sent: Tuesday, August 08, 2006 7:12 AM
Subject: [axialflux] Re:homopolar generator vs axial flux alternator

Steve,

An axial flux generator can be homopolar and will output only DC,
if you spin the central disk with magnets mounted on both sides
of the disk with the same pole facing outward, with coils mounted
on the ends on similar sized disks that are fixed, you don't have
any brushes or slip rings.

It's all in the design. A homopolar axial flux generator is one of
the most efficient designs available for a variable motive power
supply...such as wind, a small seasonal stream, etc.

I personally don't like alternators even with rectifiers to
convert to DC for battery storage because they are not as
efficient as simple homopolar generators at producing DC
power from a variable speed motive source.

Regards,

Lawrence

--- In axialflux@yahoogrou ps.com, "Steve Spence" <sspence@... > wrote:
>
> But not very related to an axial flux alternator. Homopolar
generators are a
> completely different animal. Dc outputs and requiring brushes.
>
>
>
> Steve Spence
>
> Director, Green Trust
>
> http://www.green- trust.org
>
> _____
>
> From: axialflux@yahoogrou ps.com [mailto:axialflux@yahoogrou ps.com]
On Behalf
> Of Kirk McLoren
> Sent: Friday, August 04, 2006 9:46 PM
> To: axialflux@yahoogrou ps.com
> Subject: [axialflux] relationship between flux and speed in a
generator
>
>
>
> http://www.tinaja. <http://www.tinaja. com/glib/ muse117.pdf>
> com/glib/muse117. pdf
>
>
>
> A nice resource
>
>
>
> Kirk
>

• Can we discuss this online? I would like to know more about this, and I am sure others on this list would as well. I would also be interested in Hugh s
Message 1 of 24 , Aug 8, 2006
View Source
I am sure others on this list would as well. I would also be
interested in Hugh's opinions on this.

Thanks,
Jason

On 8/8/06, Steve Spence <sspence@...> wrote:
> Talk to me more offline on this homopolar axial flux generator design so
> that I can decide whether to cover it on this board. It sounds interesting.
>
>
>
> This is the only reference I have read on this subject, and it didn't look
> like what you are describing.
>
>
>
> http://en.wikipedia.org/wiki/Homopolar_generator
>
>
>
> Steve Spence
>
> Director, Green Trust
>
> http://www.green-trust.org
>
> _____
>
> From: axialflux@yahoogroups.com [mailto:axialflux@yahoogroups.com] On Behalf
> Of Lawrence Rayburn
> Sent: Tuesday, August 08, 2006 10:12 AM
> To: axialflux@yahoogroups.com
> Subject: [axialflux] Re:homopolar generator vs axial flux alternator
>
>
>
> Steve,
>
> An axial flux generator can be homopolar and will output only DC,
> if you spin the central disk with magnets mounted on both sides
> of the disk with the same pole facing outward, with coils mounted
> on the ends on similar sized disks that are fixed, you don't have
> any brushes or slip rings.
>
> It's all in the design. A homopolar axial flux generator is one of
> the most efficient designs available for a variable motive power
> supply...such as wind, a small seasonal stream, etc.
>
> I personally don't like alternators even with rectifiers to
> convert to DC for battery storage because they are not as
> efficient as simple homopolar generators at producing DC
> power from a variable speed motive source.
>
> Regards,
>
> Lawrence
>
> --- In axialflux@yahoogrou <mailto:axialflux%40yahoogroups.com> ps.com,
> "Steve Spence" <sspence@...> wrote:
> >
> > But not very related to an axial flux alternator. Homopolar
> generators are a
> > completely different animal. Dc outputs and requiring brushes.
> >
> >
> >
> > Steve Spence
> >
> > Director, Green Trust
> >
> > http://www.green- <http://www.green-trust.org> trust.org
> >
> > _____
> >
> > From: axialflux@yahoogrou <mailto:axialflux%40yahoogroups.com> ps.com
> [mailto:axialflux@yahoogrou <mailto:axialflux%40yahoogroups.com> ps.com]
> On Behalf
> > Of Kirk McLoren
> > Sent: Friday, August 04, 2006 9:46 PM
> > To: axialflux@yahoogrou <mailto:axialflux%40yahoogroups.com> ps.com
> > Subject: [axialflux] relationship between flux and speed in a
> generator
> >
> >
> >
> > http://www.tinaja. <http://www.tinaja.
> <http://www.tinaja.com/glib/muse117.pdf> com/glib/muse117.pdf>
> > com/glib/muse117.pdf
> >
> >
> >
> > A nice resource
> >
> >
> >
> > Kirk
> >
>
>
>
>
>
• Tesla improved the design quite a bit. He slotted it so it didnt short itself. Didnt see Tesla at Wiki Kirk Steve Spence wrote: v :*
Message 1 of 24 , Aug 8, 2006
View Source
Tesla improved the design quite a bit. He slotted it so it didnt short itself.
Didnt see Tesla at Wiki

Kirk

Steve Spence <sspence@...> wrote:
Talk to me more offline on this homopolar axial flux generator design so that I can decide whether to cover it on this board. It sounds interesting.

This is the only reference I have read on this subject, and it didnÂ’t look like what you are describing.

http://en.wikipedia.org/wiki/Homopolar_generator

Steve Spence
Director, Green Trust
http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Lawrence Rayburn
Sent: Tuesday, August 08, 2006 10:12 AM
To: axialflux@yahoogroups.com
Subject: [axialflux] Re:homopolar generator vs axial flux alternator

Steve,

An axial flux generator can be homopolar and will output only DC,
if you spin the central disk with magnets mounted on both sides
of the disk with the same pole facing outward, with coils mounted
on the ends on similar sized disks that are fixed, you don't have
any brushes or slip rings.

It's all in the design. A homopolar axial flux generator is one of
the most efficient designs available for a variable motive power
supply...such as wind, a small seasonal stream, etc.

I personally don't like alternators even with rectifiers to
convert to DC for battery storage because they are not as
efficient as simple homopolar generators at producing DC
power from a variable speed motive source.

Regards,

Lawrence

--- In axialflux@yahoogrou ps.com, "Steve Spence" <sspence@... > wrote:
>
> But not very related to an axial flux alternator. Homopolar
generators are a
> completely different animal. Dc outputs and requiring brushes.
>
>
>
> Steve Spence
>
> Director, Green Trust
>
> http://www.green- trust.org
>
> _____
>
> From: axialflux@yahoogrou ps.com [mailto:axialflux@yahoogrou ps.com]
On Behalf
> Of Kirk McLoren
> Sent: Friday, August 04, 2006 9:46 PM
> To: axialflux@yahoogrou ps.com
> Subject: [axialflux] relationship between flux and speed in a
generator
>
>
>
> http://www.tinaja. <http://www.tinaja. com/glib/ muse117.pdf>
> com/glib/muse117. pdf
>
>
>
> A nice resource
>
>
>
> Kirk
>

Groups are talking. We´re listening. Check out the handy changes to Yahoo! Groups.

• Sure, go for it. I don t see it as a axial flux, but maybe it s close enough to consider. I m willing to be persuaded. Steve Spence Director, Green Trust
Message 1 of 24 , Aug 8, 2006
View Source

Sure, go for it. I don’t see it as a axial flux, but maybe it’s close enough to consider. I’m willing to be persuaded.

Steve Spence

Director, Green Trust

http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Jason MeGahee
Sent: Tuesday, August 08, 2006 1:05 PM
To: axialflux@yahoogroups.com
Subject: [axialflux] Re: homopolar generator vs axial flux alternator

I am sure others on this list would as well. I would also be
interested in Hugh's opinions on this.

Thanks,
Jason

On 8/8/06, Steve Spence <sspence@green- trust.org> wrote:

> Talk to me more offline on this homopolar axial flux generator design so
> that I can decide whether to cover it on this board. It sounds
interesting.
>
>
>
> This is the only reference I have read on this subject, and it didn't look
> like what you are describing.
>
>
>
> http://en.wikipedia .org/wiki/ Homopolar_ generator
>
>
>
> Steve Spence
>
> Director, Green Trust
>
> http://www.green- trust.org
>
> _____
>
> From: axialflux@yahoogrou ps.com
[mailto:axialflux@yahoogrou ps.com] On Behalf
> Of Lawrence
Rayburn
> Sent: Tuesday, August 08, 2006 10:12 AM
> To: axialflux@yahoogrou ps.com
> Subject: [axialflux] Re:homopolar generator vs axial flux alternator
>
>
>
> Steve,
>
> An axial flux generator can be homopolar and will output only DC,
> if you spin the central disk with magnets mounted on both sides
> of the disk with the same pole facing outward, with coils mounted
> on the ends on similar sized disks that are fixed, you don't have
> any brushes or slip rings.
>
> It's all in the design. A homopolar axial flux generator is one of
> the most efficient designs available for a variable motive power
> supply...such as wind, a small seasonal stream, etc.
>
> I personally don't like alternators even with rectifiers to
> convert to DC for battery storage because they are not as
> efficient as simple homopolar generators at producing DC
> power from a variable speed motive source.
>
> Regards,
>
> Lawrence
>
> --- In axialflux@yahoogrou <mailto:axialflux% 40yahoogroups. com>
ps.com,
> "Steve Spence" <sspence@... > wrote:
> >
> > But not very related to an axial flux alternator. Homopolar
> generators are a
> > completely different animal. Dc outputs and requiring brushes.
> >
> >
> >
> > Steve Spence
> >
> > Director, Green Trust
> >
> > http://www.green- <
href="http://www.green-trust.org">http://www.green- trust.org> trust.org
> >
> > _____
> >
> > From: axialflux@yahoogrou <mailto:axialflux% 40yahoogroups. com>
ps.com
> [mailto:axialflux@ yahoogrou <mailto:axialflux% 40yahoogroups. com>
ps.com]
> On Behalf
> > Of Kirk McLoren
> > Sent: Friday, August 04, 2006 9:46 PM
> > To: axialflux@yahoogrou <mailto:axialflux% 40yahoogroups. com>
ps.com
> > Subject: [axialflux] relationship between flux and speed in a
> generator
> >
> >
> >
> > http://www.tinaja. <
href="http://www.tinaja.">http://www.tinaja.
com/glib/muse117. pdf>
> > com/glib/muse117. pdf
> >
> >
> >
> > A nice resource
> >
> >
> >
> > Kirk
> >
>
>
>
>
>

• Well, here is good. So is otherpower.com, and the other links listed at this group s home page, http://groups.yahoo.com/group/axialflux/ Steve Spence Director,
Message 1 of 24 , Aug 8, 2006
View Source
Well, here is good. So is otherpower.com, and the other links listed at this

Steve Spence
Director, Green Trust
http://www.green-trust.org
________________________________________
From: axialflux@yahoogroups.com [mailto:axialflux@yahoogroups.com] On Behalf
Of Dan Clarke
Sent: Tuesday, August 08, 2006 12:13 PM
To: axialflux@yahoogroups.com
Subject: Re: [axialflux] Re:homopolar generator vs axial flux alternator

Hi,
Â
I'm new to this stuff.
Is there a website where the subject is discussed in a basic way? I'd like
to catch up.
Â
Thanks,
Dan
• Lawrence - maybe I have a misconception but from what I understand you re dead wrong. You cannot build a homo-polar axial flux generator that produces
Message 1 of 24 , Aug 8, 2006
View Source
Lawrence - maybe I have a misconception but from what I understand
you're dead wrong. You cannot build a 'homo-polar axial flux
generator' that produces direct current without brushes/commutator or
rectifiers. I wonder why you tell people stuff like this... it only
causes confusion.

Perhaps I'm wrong and if so forgive me - but if it is so simple can
you show us a single example of such a thing? If it was so simple and
efficient I expect folks would have been doing it now for... 100+
years or so.

I'm fairly certain it's impossible.
- DanB

--- In axialflux@yahoogroups.com, "Lawrence Rayburn"
<lawrencerayburn@...> wrote:
>
> Steve,
>
> An axial flux generator can be homopolar and will output only DC,
> if you spin the central disk with magnets mounted on both sides
> of the disk with the same pole facing outward, with coils mounted
> on the ends on similar sized disks that are fixed, you don't have
> any brushes or slip rings.
>
> It's all in the design. A homopolar axial flux generator is one of
> the most efficient designs available for a variable motive power
> supply...such as wind, a small seasonal stream, etc.
>
> I personally don't like alternators even with rectifiers to
> convert to DC for battery storage because they are not as
> efficient as simple homopolar generators at producing DC
> power from a variable speed motive source.
>
> Regards,
>
> Lawrence
>
>
>
>
> --- In axialflux@yahoogroups.com, "Steve Spence" <sspence@> wrote:
> >
> > But not very related to an axial flux alternator. Homopolar
> generators are a
> > completely different animal. Dc outputs and requiring brushes.
> >
> >
> >
> > Steve Spence
> >
> > Director, Green Trust
> >
> > http://www.green-trust.org
> >
> > _____
> >
> > From: axialflux@yahoogroups.com [mailto:axialflux@yahoogroups.com]
> On Behalf
> > Of Kirk McLoren
> > Sent: Friday, August 04, 2006 9:46 PM
> > To: axialflux@yahoogroups.com
> > Subject: [axialflux] relationship between flux and speed in a
> generator
> >
> >
> >
> > http://www.tinaja. <http://www.tinaja.com/glib/muse117.pdf>
> > com/glib/muse117.pdf
> >
> >
> >
> > A nice resource
> >
> >
> >
> > Kirk
> >
>
• I always thought of homopolar generators as very low voltage. Check this out - 500 volts Kirk
Message 1 of 24 , Aug 8, 2006
View Source
I always thought of homopolar generators as very low voltage.
Check this out - 500 volts

Kirk

Research Org IEEE Trans. Magn. ; Vol/Issue: MAG-22:6 GA Technologies, Inc., P.O. Box 85608, San Diego, CA 92138
A homopolar generator with 500 volts output is being designed and built as a pulsed power source.^ A key component used in achieving this high output voltage is the 5 tesla field coil.^ A superconducting coil is required for a compact configuration that operates above the saturation of iron.^ The coil case is 158 cm long and has an outside diameter of 137 cm with a 79 cm warm bore for installation of the generator rotor assembly.^ This large, intrinsically stable coil was designed to achieve a uniform magnetic field in the area of the rotor brushes.^ The coil was wound with 87.5 km of copper-stabilized niobium/titanium superconductor in an epoxy matrix.^ Fabrication of the coil and its containment cryostat is complete, and it is being used in the high-voltage homopolar generator test program.

Steve Spence <sspence@...> wrote:
Talk to me more offline on this homopolar axial flux generator design so that I can decide whether to cover it on this board. It sounds interesting.

This is the only reference I have read on this subject, and it didnÂ’t look like what you are describing.

http://en.wikipedia.org/wiki/Homopolar_generator

Steve Spence
Director, Green Trust
http://www.green-trust.org

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of Lawrence Rayburn
Sent: Tuesday, August 08, 2006 10:12 AM
To: axialflux@yahoogroups.com
Subject: [axialflux] Re:homopolar generator vs axial flux alternator

Steve,

An axial flux generator can be homopolar and will output only DC,
if you spin the central disk with magnets mounted on both sides
of the disk with the same pole facing outward, with coils mounted
on the ends on similar sized disks that are fixed, you don't have
any brushes or slip rings.

It's all in the design. A homopolar axial flux generator is one of
the most efficient designs available for a variable motive power
supply...such as wind, a small seasonal stream, etc.

I personally don't like alternators even with rectifiers to
convert to DC for battery storage because they are not as
efficient as simple homopolar generators at producing DC
power from a variable speed motive source.

Regards,

Lawrence

--- In axialflux@yahoogrou ps.com, "Steve Spence" <sspence@... > wrote:
>
> But not very related to an axial flux alternator. Homopolar
generators are a
> completely different animal. Dc outputs and requiring brushes.
>
>
>
> Steve Spence
>
> Director, Green Trust
>
> http://www.green- trust.org
>
> _____
>
> From: axialflux@yahoogrou ps.com [mailto:axialflux@yahoogrou ps.com]
On Behalf
> Of Kirk McLoren
> Sent: Friday, August 04, 2006 9:46 PM
> To: axialflux@yahoogrou ps.com
> Subject: [axialflux] relationship between flux and speed in a
generator
>
>
>
> http://www.tinaja. <http://www.tinaja. com/glib/ muse117.pdf>
> com/glib/muse117. pdf
>
>
>
> A nice resource
>
>
>
> Kirk
>

Yahoo! Music Unlimited - Access over 1 million songs. Try it free.

• Dan, Let s drop back to basic definitions to get everyone on the same page, okay? Axial Flux.....what does that mean? I understand it to mean magnetic flux
Message 1 of 24 , Aug 8, 2006
View Source
Dan,

Let's drop back to basic definitions to get everyone on the same
page, okay?

Axial Flux.....what does that mean? I understand it to mean
magnetic flux lines running along an axis, revolving around an
axis...or common axle.

These magnetic flux lines are supposed to 'cut' the windings of a
coil in a manner to induce current. That means the magnetic field
flux lines must cut the coil wire at an angle, right?
But, what if the coil wire is oriented so the flux lines move parallel
to the wires? You still get electrons pushed along in the wire, do
you not? So, you are inducing voltage in the coil windings even
with that parallel orientation. If the ebb and flow of electrons
moving with magnetic flux lines cancel one another out, then you
have no output. Follow me, so far?

A homopolar magnet array presents one pole to the coil. With gaps
between the magnets, the magnetic flux breaks the coil windings
the same direction all the time and maximizes intensity and
suddenly drops off then picks up again to max as the next magnet
moves into place...so you get a type of peristaltic pulsation of
induced voltage/current....trains of electrons that want to move
in a single direct.

It's really more efficient to think of a homopolar generator
as an electron pump that turns only one direction, inducing
voltage/current in only one direction.

So, we build a disk of aluminum or brass (not steel) and place
flat circular magnets around the disk, equally spaced for balance
and oriented so only one pole is facing outward. We drill a hole
through the disk and attach a similar magnet on a common brass
bolt to the other side of the disk so that the tightened brass
bolt forces the like poles of the magnet together (and epoxy in
place). This causes the repelling magnetic flux field to wrap around
and reinforce the flux fields on the outward facing magnetic poles...
and they are all the same pole. Now we wind flat pancake coils
that are oval shaped so that half the windings are in the flux
path and the other half are facing away from the flux path of the
moving magnets. We attach these coils to round end plates of
brass or aluminum (aluminum will heat due to hysterisis...the
magnetic flux lines passing through the aluminum but doesn't do
so with brass) in fixed positions so the magnetic flux lines
excite the coil wires in one direction. This gives the electron
pump effect of the homopolar generator.

Because the magnets are spinning on the central disk, and the coils
are fixed on the end cap disks, there is no need for slip rings or
brushes to collect the DC charge.

These DC generators WORK, and work well with a windmill driving them.
The wind speed varies and the voltage output of the generator
varies....but it doesn't have to maintain 3600 RPM to produce
usable DC voltage. It will produce usable voltage at very low
speeds and still store in batteries. My modified Savonius
turns between 50 and 450 RPMs and with this generator, produces
usable voltage in 2 to 3 mph winds.

And that is the object of this exercise. To produce the most
efficient means of generating electricity from the available
wind energy.

So, the generator looks like a disk or pancake short stack with
an axle or drive shaft running through the middle.

Regards,

Lawrence

-- In axialflux@yahoogroups.com, "Dan Bartmann" <danb@...> wrote:
>
> Lawrence - maybe I have a misconception but from what I understand
> you're dead wrong. You cannot build a 'homo-polar axial flux
> generator' that produces direct current without brushes/commutator
or
> rectifiers. I wonder why you tell people stuff like this... it only
> causes confusion.
>
> Perhaps I'm wrong and if so forgive me - but if it is so simple can
> you show us a single example of such a thing? If it was so simple
and
> efficient I expect folks would have been doing it now for... 100+
> years or so.
>
> I'm fairly certain it's impossible.
> - DanB
>
> --- In axialflux@yahoogroups.com, "Lawrence Rayburn"
> <lawrencerayburn@> wrote:
> >
> > Steve,
> >
> > An axial flux generator can be homopolar and will output only DC,
> > if you spin the central disk with magnets mounted on both sides
> > of the disk with the same pole facing outward, with coils mounted
> > on the ends on similar sized disks that are fixed, you don't have
> > any brushes or slip rings.
> >
> > It's all in the design. A homopolar axial flux generator is one
of
> > the most efficient designs available for a variable motive power
> > supply...such as wind, a small seasonal stream, etc.
> >
> > I personally don't like alternators even with rectifiers to
> > convert to DC for battery storage because they are not as
> > efficient as simple homopolar generators at producing DC
> > power from a variable speed motive source.
> >
> > Regards,
> >
> > Lawrence
> >
> >
> >
> >
> > --- In axialflux@yahoogroups.com, "Steve Spence" <sspence@> wrote:
> > >
> > > But not very related to an axial flux alternator. Homopolar
> > generators are a
> > > completely different animal. Dc outputs and requiring brushes.
> > >
> > >
> > >
> > > Steve Spence
> > >
> > > Director, Green Trust
> > >
> > > http://www.green-trust.org
> > >
> > > _____
> > >
> > > From: axialflux@yahoogroups.com
[mailto:axialflux@yahoogroups.com]
> > On Behalf
> > > Of Kirk McLoren
> > > Sent: Friday, August 04, 2006 9:46 PM
> > > To: axialflux@yahoogroups.com
> > > Subject: [axialflux] relationship between flux and speed in a
> > generator
> > >
> > >
> > >
> > > http://www.tinaja. <http://www.tinaja.com/glib/muse117.pdf>
> > > com/glib/muse117.pdf
> > >
> > >
> > >
> > > A nice resource
> > >
> > >
> > >
> > > Kirk
> > >
> >
>
• Not really a backyard DIY project, is it? I think I ll stick with our usual type of axial flux genny until the other ones don t have to be made out of
Message 1 of 24 , Aug 8, 2006
View Source
Not really a backyard DIY project, is it? I think I'll stick with our
usual type of axial flux genny until the other ones don't have to be

Peace,
ldb

Larry D. Barr
K5WLF
Owner, Rebel Wolf Energy Systems
http://www.rebelwolf.com/
Founder-Moderator, 12VDC Power Group
http://groups.yahoo.com/group/12VDC_Power

Kirk McLoren wrote:
> I always thought of homopolar generators as very low voltage.
> Check this out - 500 volts
> Kirk
> http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=5525789
> <http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=5525789>
> IEEE Trans. Magn. ; Vol/Issue: MAG-22:6
> Research Org GA Technologies, Inc., P.O. Box 85608, San Diego, CA 92138
>
> A homopolar generator with 500 volts output is being designed and
> built as a pulsed power source.^ A key component used in achieving
> this high output voltage is the 5 tesla field coil.^ A superconducting
> coil is required for a compact configuration that operates above the
> saturation of iron.^ The coil case is 158 cm long and has an outside
> diameter of 137 cm with a 79 cm warm bore for installation of the
> generator rotor assembly.^ This large, intrinsically stable coil was
> designed to achieve a uniform magnetic field in the area of the rotor
> brushes.^ The coil was wound with 87.5 km of copper-stabilized
> niobium/titanium superconductor in an epoxy matrix.^ Fabrication of
> the coil and its containment cryostat is complete, and it is being
> used in the high-voltage homopolar generator test program.
>
> */Steve Spence <sspence@...>/* wrote:
>
> Talk to me more offline on this homopolar axial flux generator
> design so that I can decide whether to cover it on this board. It
> sounds interesting.
> This is the only reference I have read on this subject, and it
> didnâ€™t look like what you are describing.
> http://en.wikipedia.org/wiki/Homopolar_generator
> Steve Spence
> Director, Green Trust
> http://www.green-trust.org
> ------------------------------------------------------------------------
> *From:* axialflux@yahoogroups.com
> [mailto:axialflux@yahoogroups.com] *On Behalf Of *Lawrence Rayburn
> *Sent:* Tuesday, August 08, 2006 10:12 AM
> *To:* axialflux@yahoogroups.com
> *Subject:* [axialflux] Re:homopolar generator vs axial flux alternator
> Steve,
>
> An axial flux generator can be homopolar and will output only DC,
> if you spin the central disk with magnets mounted on both sides
> of the disk with the same pole facing outward, with coils mounted
> on the ends on similar sized disks that are fixed, you don't have
> any brushes or slip rings.
>
> It's all in the design. A homopolar axial flux generator is one of
> the most efficient designs available for a variable motive power
> supply...such as wind, a small seasonal stream, etc.
>
> I personally don't like alternators even with rectifiers to
> convert to DC for battery storage because they are not as
> efficient as simple homopolar generators at producing DC
> power from a variable speed motive source.
>
> Regards,
>
> Lawrence
>
> --- In axialflux@yahoogroups.com
> <mailto:axialflux%40yahoogroups.com>, "Steve Spence" <sspence@...>
> wrote:
> >
> > But not very related to an axial flux alternator. Homopolar
> generators are a
> > completely different animal. Dc outputs and requiring brushes.
> >
> >
> >
> > Steve Spence
> >
> > Director, Green Trust
> >
> > http://www.green-trust.org <http://www.green-trust.org/>
> >
> > _____
> >
> > From: axialflux@yahoogroups.com
> <mailto:axialflux%40yahoogroups.com>
> [mailto:axialflux@yahoogroups.com
> <mailto:axialflux%40yahoogroups.com>]
> On Behalf
> > Of Kirk McLoren
> > Sent: Friday, August 04, 2006 9:46 PM
> > To: axialflux@yahoogroups.com <mailto:axialflux%40yahoogroups.com>
> > Subject: [axialflux] relationship between flux and speed in a
> generator
> >
> >
> >
> > http://www.tinaja. <http://www.tinaja./>
> <http://www.tinaja.com/glib/muse117.pdf
> <http://www.tinaja.com/glib/muse117.pdf>>
> > com/glib/muse117.pdf
> >
> >
> >
> > A nice resource
> >
> >
> >
> > Kirk
> >
>
>
> ------------------------------------------------------------------------
> Yahoo! Music Unlimited - Access over 1 million songs. Try it free.
> <http://pa.yahoo.com/*http://us.rd.yahoo.com/evt=36035/*http://music.yahoo.com/unlimited/%20>
>
>
• Lawrence, I follow most of what you have said but still have a few questions (please forgive me if I sound like an idiot, I have not actually built an
Message 1 of 24 , Aug 9, 2006
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Lawrence,

I follow most of what you have said but still have a few questions
(please forgive me if I sound like an idiot, I have not actually built
an alternator or generator yet but have been looking and reading for

> So, we build a disk of aluminum or brass (not steel) and place
> flat circular magnets around the disk, equally spaced for balance
> and oriented so only one pole is facing outward.

Why aluminium or brass? Would any non-ferrous material work? What

We drill a hole
> through the disk and attach a similar magnet on a common brass
> bolt to the other side of the disk so that the tightened brass
> bolt forces the like poles of the magnet together (and epoxy in
> place). This causes the repelling magnetic flux field to wrap around
> and reinforce the flux fields on the outward facing magnetic poles...
> and they are all the same pole.

I think I understand what you are saying here but I can't understand
why. So you have a magnet, we'll say the N face is pointing away from
the disk, that is connected with a brass bolt thru the disk to another
magnet with its N face pointing away from the disk. This seems very
odd and like it may be prone to failure over time, but more
importantly I don't understand the purpose. If it is to strengthen the
outward facing mag. field, why not just use a bigger magnet?

Now we wind flat pancake coils
> that are oval shaped so that half the windings are in the flux
> path and the other half are facing away from the flux path of the
> moving magnets. We attach these coils to round end plates of
> brass or aluminum (aluminum will heat due to hysterisis...the
> magnetic flux lines passing through the aluminum but doesn't do
> so with brass) in fixed positions so the magnetic flux lines
> excite the coil wires in one direction.

This sounds like you are describing the same setup (at least for this
part) that is used in Hugh's plans. Perhaps my confusion could be
ameliorated by a diagram or pictures of your own generator.
Also, is there two of these disks with coils, one on either side of
the magnet arrangement? If that is the case I can begin to understand
why you have the strange mag. setup. Otherwise, I'm still a bit
confused.

>
> Because the magnets are spinning on the central disk, and the coils
> are fixed on the end cap disks, there is no need for slip rings or
> brushes to collect the DC charge.
>

How are the coils wired together and the output collected? I would
assume that there must be some other electronic component in the line
that regulates the voltage sent to the batteries?

So, for the same materials (i.e. magnets and wire) and the same RPM
you are saying that this arrangement produces more power than the
axial flux alt. of Hugh's design? Have you done any side by side bench
testing? Thanks for your help getting me to understand this. I am very
close to building this part of my project and appreciate all of the
information I can get.

Jason
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