Posted by Andy Baker on November 29, 2004, 1:19 pm
Greetings and apologies if I'm off topic...
I am currently working on an experimental and completely home built
co-generation system, however, I'm not an expert in the following area, so I
seek the guidance of others -
I have a turbine shaft spinning at about 10,000 RPM and I wonder if there is
a generator I can direct drive from this. I'd like to avoid a gearbox at all
costs. Total output will be anywhere from 4-10KW. DC or high frequency AC
output is fine, but I don't know if I'd want to deal with anything over 400
Hz.
I know some people make their own alternators out of rare earth magnets and
hand windings for windmills and such, but I don't know what the practical
limits for them are, and most of them that I've seen have so many magnets in
them that the frequency would be nuts at such a high RPM - Maybe an un-godly
number of phases would be called for to accomplish such a feat? Though I'm
not sure if I'd ever want anything "I" built whipping around at 10,000 RPM
Does anybody have any input?
Thanks!
Andy Baker
Posted by Me on November 29, 2004, 1:48 pm
> Greetings and apologies if I'm off topic...
>
> I am currently working on an experimental and completely home built
> co-generation system, however, I'm not an expert in the following area, so I
> seek the guidance of others -
>
> I have a turbine shaft spinning at about 10,000 RPM and I wonder if there is
> a generator I can direct drive from this. I'd like to avoid a gearbox at all
> costs. Total output will be anywhere from 4-10KW. DC or high frequency AC
> output is fine, but I don't know if I'd want to deal with anything over 400
> Hz.
>
> I know some people make their own alternators out of rare earth magnets and
> hand windings for windmills and such, but I don't know what the practical
> limits for them are, and most of them that I've seen have so many magnets in
> them that the frequency would be nuts at such a high RPM - Maybe an un-godly
> number of phases would be called for to accomplish such a feat? Though I'm
> not sure if I'd ever want anything "I" built whipping around at 10,000 RPM
>
> Does anybody have any input?
>
>
> Thanks!
>
>
> Andy Baker
>
>
If your looking for 10K Rpm, you should generate DC and then invert
it external to the generator. there certainly are OEM's that can build
units for that spec.
Me
Posted by John Beardmore on November 29, 2004, 1:56 pm
>I am currently working on an experimental and completely home built
>co-generation system, however, I'm not an expert in the following area, so I
>seek the guidance of others -
>I have a turbine shaft spinning at about 10,000 RPM and I wonder if there is
>a generator I can direct drive from this. I'd like to avoid a gearbox at all
>costs. Total output will be anywhere from 4-10KW.
At those RPM that may be quite a challenge ! Do some sums on the forces
!
> DC or high frequency AC
>output is fine, but I don't know if I'd want to deal with anything over 400
>Hz.
Rectify it. The higher the frequency and the more phase, the smaller
the capacitors.
>I know some people make their own alternators out of rare earth magnets and
>hand windings for windmills and such, but I don't know what the practical
>limits for them are,
The whole point about those is that they are low RPM.
> and most of them that I've seen have so many magnets in
>them that the frequency would be nuts at such a high RPM - Maybe an un-godly
>number of phases would be called for to accomplish such a feat?
Three is normal.
> Though I'm
>not sure if I'd ever want anything "I" built whipping around at 10,000 RPM
Nor me.
Time for google I think !
J/.
--
John Beardmore
Posted by Andy Baker on November 29, 2004, 3:43 pm
Thanks
There's plenty of static to be had in a google search, but as I plug away, I
find a few things, most however are in the 500 KW and up range :-(
Andy
>>I am currently working on an experimental and completely home built
>>co-generation system, however, I'm not an expert in the following area, so
>>I
>>seek the guidance of others -
>>
>>I have a turbine shaft spinning at about 10,000 RPM and I wonder if there
>>is
>>a generator I can direct drive from this. I'd like to avoid a gearbox at
>>all
>>costs. Total output will be anywhere from 4-10KW.
> At those RPM that may be quite a challenge ! Do some sums on the forces !
>> DC or high frequency AC
>>output is fine, but I don't know if I'd want to deal with anything over
>>400
>>Hz.
> Rectify it. The higher the frequency and the more phase, the smaller the
> capacitors.
>>I know some people make their own alternators out of rare earth magnets
>>and
>>hand windings for windmills and such, but I don't know what the practical
>>limits for them are,
> The whole point about those is that they are low RPM.
>> and most of them that I've seen have so many magnets in
>>them that the frequency would be nuts at such a high RPM - Maybe an
>>un-godly
>>number of phases would be called for to accomplish such a feat?
> Three is normal.
>> Though I'm
>>not sure if I'd ever want anything "I" built whipping around at 10,000 RPM
> Nor me.
> Time for google I think !
> J/.
> --
> John Beardmore
Posted by Gymy Bob on November 29, 2004, 5:20 pm
I think you will be replacing bearings about once a month. Wood routers have
this problem at those speeds and keep any kind of silicone grease away from
it. Long fibres will burn it up.
> Greetings and apologies if I'm off topic...
> I am currently working on an experimental and completely home built
> co-generation system, however, I'm not an expert in the following area, so
I
> seek the guidance of others -
> I have a turbine shaft spinning at about 10,000 RPM and I wonder if there
is
> a generator I can direct drive from this. I'd like to avoid a gearbox at
all
> costs. Total output will be anywhere from 4-10KW. DC or high frequency AC
> output is fine, but I don't know if I'd want to deal with anything over
400
> Hz.
> I know some people make their own alternators out of rare earth magnets
and
> hand windings for windmills and such, but I don't know what the practical
> limits for them are, and most of them that I've seen have so many magnets
in
> them that the frequency would be nuts at such a high RPM - Maybe an
un-godly
> number of phases would be called for to accomplish such a feat? Though I'm
> not sure if I'd ever want anything "I" built whipping around at 10,000 RPM
> Does anybody have any input?
> Thanks!
> Andy Baker
>
> I am currently working on an experimental and completely home built
> co-generation system, however, I'm not an expert in the following area, so I
> seek the guidance of others -
>
> I have a turbine shaft spinning at about 10,000 RPM and I wonder if there is
> a generator I can direct drive from this. I'd like to avoid a gearbox at all
> costs. Total output will be anywhere from 4-10KW. DC or high frequency AC
> output is fine, but I don't know if I'd want to deal with anything over 400
> Hz.
>
> I know some people make their own alternators out of rare earth magnets and
> hand windings for windmills and such, but I don't know what the practical
> limits for them are, and most of them that I've seen have so many magnets in
> them that the frequency would be nuts at such a high RPM - Maybe an un-godly
> number of phases would be called for to accomplish such a feat? Though I'm
> not sure if I'd ever want anything "I" built whipping around at 10,000 RPM
>
> Does anybody have any input?
>
>
> Thanks!
>
>
> Andy Baker
>
>