I require a 3-phase power source of 115VAC @ 400Hz with an output of around
100mA or so. I would like to power this from 12-14V DC.
Does anyone have any suggestions about a circuit I could use - or design one
for me?
The connections to the device I want to run (an ancient attitude gauge or
artificial horizon from a vintage aircraft) is delta configuration
(delta-wound gyro motors) - no centre or common connector.
Cheers,
Joe

Hi Joe,

You could contact some stores that cater to land surveyors. There are
some three-phase 115V 400Hz gyros used in that field, or at least they
used to. Since they often work off grid using a 12V battery there should
be inverters offered. I have seen one a long time ago and since these
gyros use so much power the inverter is kind of large, it was the size
of a brick.

Regards, Joerg

http://www.analogconsultants.com

Will try that lead Joerg. Thank you.
Although that sounds like it might be expensive....
Cheers,
Joe

"Joerg" wrote in message
...
Hi Joe,

You could contact some stores that cater to land surveyors. There are
some three-phase 115V 400Hz gyros used in that field, or at least they
used to. Since they often work off grid using a 12V battery there should
be inverters offered. I have seen one a long time ago and since these
gyros use so much power the inverter is kind of large, it was the size
of a brick.

Regards, Joerg

http://www.analogconsultants.com

"Joe in Bendigo"

I require a 3-phase power source of 115VAC @ 400Hz with an output of
around
100mA or so. I would like to power this from 12-14V DC.
Does anyone have any suggestions about a circuit I could use - or design
one
for me?


** A switch mode, 400 Hz three phase inverter for use with avionics was
published in "Electronics World " in the February 1999 issue, p127.

But it ain' t simple.




............ Phil

Hi Joe,

Will try that lead Joerg. Thank you.
Although that sounds like it might be expensive....


Yes, it could be expensive. But you might also try surplus dealers that
sell discarded mil and industrial gear. With some luck one of them sits
on a stash of those and is eager to let them go. That's where I used to
get the best deals.

Regards, Joerg

http://www.analogconsultants.com

"Paul Mathews"

Transformer VA rating could be considerably
less than the wattage of your load, since power ratings would be
effectively higher at 400Hz (compared to their 50 or 60Hz VA rating
frequency).



** The VA rating at 400 Hz will be virtually the same as at 50/60 Hz. The
magnetising current in the primary will reduce at the higher operating
frequency but since this is a small fraction of the rated current ( indeed
small for a toroidal) there is not much overall change.




.............. Phil