[GreenKeys] Navy radio question...

[John Lawson]

On Sun, 8 Jan 2006, roy.morgan at nist.gov wrote:

> Quoting Andreas Müller <dd1lm at t-online.de>:
>
>> ... power supplies for the URT-23... PP-3916 and is made for 440V, 60Hz, 3P....
> There is another one which has double size and as far as I know is made for 1P
> power.
>
> Andreas,
>
>
> A fourth way is, as you might guess, solid state power inverters. It appears
> that one company has a patent on this technology and so has had no competition
> in supplying systems to do the job.  Now, it appears, a contender has developed


   Depending on The Budget - I would also offer that there is no lack of 
3-phase variable-speed motor controllers, available from every industrial 
electrical supplier, and made by many companies - such as ASEA/BB, GE, 
Allis-Chalmers, Minarik, etc etc.

   I have used these extensively in connection with motors having 
permanent-magnet rotors and three-phase stators for very 'smooth' control 
of movie projectors - up to 5 HP (3.7KW) size. But you can get them for 
any output, and many will take (at these power levels) 220/440 single 
phase and output 3-phase, using digital waveform synthesis, and power 
amplifiers - much like a switching supply.

   For a fixed radio equipment power supply, the simplest, cheapest 
controller would more than suffice, and it's parameters left at one output 
voltage and frequency. One advantage to this scheme is that 'soft start' 
(voltage ramp) is easily obtained through the setting of a single 
parameter with no extra hardware needed.


   Just my 200 millidollar...


Cheers

John   KB6SCO