Single phase 50/60 to 3 phase 400Hz 115V

[TTman]

Been looking at commercial units
Anything from $15K- $50K
Way beyond our budget.
Is there a simple solution ? We need to be able to vary the 3Phase by +/-
15% ish and the 400Hz could be +/- 5% ish.
We need it to drive/test military equipment that has 3 phase 400hz i/p,
current draw up to 2 amps max.
This would be used for a quick and dirty test as the full test is done by
the client.
TIA

 

[PeterD]

Been looking at commercial units
Anything from $15K- $50K
Way beyond our budget.
Is there a simple solution ? We need to be able to vary the 3Phase by +/-
15% ish and the 400Hz could be +/- 5% ish.
We need it to drive/test military equipment that has 3 phase 400hz i/p,
current draw up to 2 amps max.
This would be used for a quick and dirty test as the full test is done by
the client.
TIA

How much power?

 

[Rich Webb]

Been looking at commercial units
Anything from $15K- $50K
Way beyond our budget.
Is there a simple solution ? We need to be able to vary the 3Phase by +/-
15% ish and the 400Hz could be +/- 5% ish.
We need it to drive/test military equipment that has 3 phase 400hz i/p,
current draw up to 2 amps max.
This would be used for a quick and dirty test as the full test is done by
the client.

You're looking for 230 (say 250-ish) VA. Do-able. We've done single
phase 400 Hz for synchro reference/excitation using a standard audio
function generator to an audio amp to a transformer. The setup used a
Kenwood 5204 amp and a likely xformer from the miscellaneous heap.
<http://www.amazon.com/Kenwood-KAC-5204-Stereo-Amplifier-Variable/dp/B001Q9ER8K>
but the paint-burners/car-rockers may have better ones nowadays.

A microcontroller set up as a 3-phase DDS should be do-able at 400 Hz
into, say, three serial DACs with a common load line. Then three amps +
transformers. Hmmm... Wye or delta?

Could be done. Could be fun!

 

[tm]

Been looking at commercial units
Anything from $15K- $50K
Way beyond our budget.
Is there a simple solution ? We need to be able to vary the 3Phase by +/-
15% ish and the 400Hz could be +/- 5% ish.
We need it to drive/test military equipment that has 3 phase 400hz i/p,
current draw up to 2 amps max.
This would be used for a quick and dirty test as the full test is done by
the client.
TIA

Look for a variable frequency three phase motor drive that will run on 240
single or 208 three phase.

Here is one:

http://cgi.ebay.com/3-HP-Single-Thr...lectrical_Equipment_Tools&hash=item519932b542


Should do just what you want.


tm

 

[TTman]

You're looking for 230 (say 250-ish) VA. Do-able. We've done single
phase 400 Hz for synchro reference/excitation using a standard audio
function generator to an audio amp to a transformer. The setup used a
Kenwood 5204 amp and a likely xformer from the miscellaneous heap.
<http://www.amazon.com/Kenwood-KAC-5204-Stereo-Amplifier-Variable/dp/B001Q9ER8K>
but the paint-burners/car-rockers may have better ones nowadays.

A microcontroller set up as a 3-phase DDS should be do-able at 400 Hz
into, say, three serial DACs with a common load line. Then three amps +
transformers. Hmmm... Wye or delta?

Could be done. Could be fun!

Interesting ! No problem with the DDS/Micro/ DAC/ AMP.....
Would a torroid transformer work at 400Hz or would that have to be something
'special' ?

 

[tm]

Been looking at commercial units
Anything from $15K- $50K
Way beyond our budget.
Is there a simple solution ? We need to be able to vary the 3Phase by +/-
15% ish and the 400Hz could be +/- 5% ish.
We need it to drive/test military equipment that has 3 phase 400hz i/p,
current draw up to 2 amps max.
This would be used for a quick and dirty test as the full test is done by
the client.
TIA

Here is another variable frequency drive that is 240 single phase in
and 0-240 volt ac 0 to 400 Hz three phase. Only $15 bucks. 1500 VA.

http://cgi.ebay.com/Siemens-Microma...t=BI_Control_Systems_PLCs&hash=item2c5e5af37e


tm

 

[Jamie]

Been looking at commercial units
Anything from $15K- $50K
Way beyond our budget.
Is there a simple solution ? We need to be able to vary the 3Phase by +/-
15% ish and the 400Hz could be +/- 5% ish.
We need it to drive/test military equipment that has 3 phase 400hz i/p,
current draw up to 2 amps max.
This would be used for a quick and dirty test as the full test is done by
the client.
TIA

You can buy inverters that operate from single phase that will generate
3 phase with frequency output up to 400Hz for most of them.

something for you to look at, this drive will accept single phase
input of 115V and generate 3 phase out. You can also get one that
accepts 115v input and generates 230 out..

In either case, you just set your min/max frequency to what you need.


http://www.baldor.com/support/literature_load.asp?LitNumber=FL767

Jamie

 

[Phil Allison]

"TTman"

Interesting ! No problem with the DDS/Micro/ DAC/ AMP.....

** That "AMP" might be a big problem if it has to drive a mains
transformer to anywhere near magnetic saturation conditions.

Any sudden start ( or stop and restart) of a 50/60 Hz drive signal will case
a full inrush surge to occur - no audio amp can cope with the primary
saturation current of a mains tranny of a hundred VA or more.

Only professional power amps with first class VI protection and limiting
circuits would survive.

Would a torroid transformer work at 400Hz or would that have to be
something 'special' ?

** Most mains trannies are OK up to 400 Hz - toroidals are good to 10kHz
or more.

But the latter exhibit the very worst inrush surges.

Nothing is as easy at it first looks.



.... Phil

 

[josephkk]

You're looking for 230 (say 250-ish) VA. Do-able. We've done single

Actually about 400 VA, it is 3 phase. Not too bad if there is no motor
load involved. For motors the start currents are easily over 10 times the
run current. You might also want a good 3 phase transformer (E-I cores
only) with a tertiary harmonic suppression winding.

 

[josephkk]

Here is another variable frequency drive that is 240 single phase in
and 0-240 volt ac 0 to 400 Hz three phase. Only $15 bucks. 1500 VA.

http://cgi.ebay.com/Siemens-Microma...t=BI_Control_Systems_PLCs&hash=item2c5e5af37e


tm

Depends on the testing needs, variable frequency drives do not actually
put out sine waves. Though that can be fixed with LC filters ($$$$)

?-)

 

[tm]

Here is another variable frequency drive that is 240 single phase in
and 0-240 volt ac 0 to 400 Hz three phase. Only $15 bucks. 1500 VA.

http://cgi.ebay.com/Siemens-Microma...t=BI_Control_Systems_PLCs&hash=item2c5e5af37e


tm

Depends on the testing needs, variable frequency drives do not actually
put out sine waves. Though that can be fixed with LC filters ($$$$)


__________++++++++++++++-------------------+++++++++++++++

The Micromaster is a PWM drive. It does put out sine wave 3 phase
power and will go to 400 Hz.

LC filters are cheap and the magnetics at > 400 Hz are not that bad. Maybe
some commercial line filter would work just fine.

It probably puts out cleaner power than the grid.

But for $15, how can you go wrong? Certainly cheaper than three PWM
audio amps bodged together to get three phase, right?

There are models that will run on 120 volts ac also, just do a bit of
searching. They are way cheaper than $15 - 30 k.


tm

 

[Phil Allison]

"Jamie" = Maynard A. Philbrook

( Fuckwit Radio ham KA1LPA )

just get yourself a transformer, that cleans it up nicely..

** Not certain to do any such thing.

Especially if it is a toroidal type.




..... Phil

 

[Jamie]

Depends on the testing needs, variable frequency drives do not actually
put out sine waves. Though that can be fixed with LC filters ($$$$)

?-)

just get yourself a transformer, that cleans it up nicely..

Jamie

 

[josephkk]

Depends on the testing needs, variable frequency drives do not actually
put out sine waves. Though that can be fixed with LC filters ($$$$)


__________++++++++++++++-------------------+++++++++++++++

The Micromaster is a PWM drive. It does put out sine wave 3 phase
power and will go to 400 Hz.

LC filters are cheap and the magnetics at > 400 Hz are not that bad. Maybe
some commercial line filter would work just fine.

It probably puts out cleaner power than the grid.

But for $15, how can you go wrong? Certainly cheaper than three PWM
audio amps bodged together to get three phase, right?

There are models that will run on 120 volts ac also, just do a bit of
searching. They are way cheaper than $15 - 30 k.


tm

Check it out some more, please. I claim that a typical VFD is setup to
produce sinusoidal currents in the motor rather than produce sine
voltages.

?-)

 

[tm]

Depends on the testing needs, variable frequency drives do not actually
put out sine waves. Though that can be fixed with LC filters ($$$$)


__________++++++++++++++-------------------+++++++++++++++

The Micromaster is a PWM drive. It does put out sine wave 3 phase
power and will go to 400 Hz.

LC filters are cheap and the magnetics at > 400 Hz are not that bad. Maybe
some commercial line filter would work just fine.

It probably puts out cleaner power than the grid.

But for $15, how can you go wrong? Certainly cheaper than three PWM
audio amps bodged together to get three phase, right?

There are models that will run on 120 volts ac also, just do a bit of
searching. They are way cheaper than $15 - 30 k.


tm

Check it out some more, please. I claim that a typical VFD is setup to
produce sinusoidal currents in the motor rather than produce sine
voltages.

?-)

Hi Joe,

I have one and it puts out a voltage sine wave into a resistive load. It
uses
PWM with MOSFETs running at 60 kHz into a low pass filter for each
leg. Again, it is cleaner than the grid.

Could it be that the higher (many HP) units do as you say?

Regards,
tm

 

[josephkk]

Check it out some more, please. I claim that a typical VFD is setup to
produce sinusoidal currents in the motor rather than produce sine
voltages.

?-)

Hi Joe,

I have one and it puts out a voltage sine wave into a resistive load. It
uses
PWM with MOSFETs running at 60 kHz into a low pass filter for each
leg. Again, it is cleaner than the grid.

Could it be that the higher (many HP) units do as you say?

Regards,
tm

Hmmm. They were 25 hp and larger.

 

[David Lesher]

I agree on the VFD aspect. It's a solution but do beware the need for load reactors.
Also, most must be derated if being driven with single-phase.

On the 28VDC-400Hz MG sets, you might try Fair Radio in Lima OH.

 

[Sjouke Burry]

wonder if a car alternator could be hacked, bypass the diodes to get 3
phase
and run it at 4000rpm (I think) to get 400Hz
controlling the voltage might be tricky though

-Lasse

Na, the output voltage is linear with rotation speed and magnetizing
current.
Just dont do the feedback with that current the wrong way, the connected
electronics will explode(dont ask me how I know.....).