Re: dc-ac inverter

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Sean Taylor <sstaylor-at-uiuc.edu> 


>I'd look into the inverters and such aimed at the home power market, since
>they'll have the capacities and sine wave output.
>You could also use a 20 kW 240V inverter and run it into a 240:480V dry
>transformer.


Don't have to look at ones just for the home market - there are plenty of 
high power units for marine use and R/V type use that are pure sine wave.
I would agree with the 240:480 transformer bit - much easier to do, but it 
really depends on the application - which brings me to my question:  what 
do you need 480VAC for, and why from batteries/inverter?  What's wrong with 
getting a step-up transformer and "making" 480 from the utility 
power?  That would be a pretty good sine wave, and wouldn't require lots of 
batteries either.  BTW, the multiple inverter in series thing would work IF 
you could get the frequency generating portion from one to run them all so 
that they would be in phase all the time.  You would also have to lift the 
grounds so that the secondaries of the transformers would all be 
isolated.  A relatively common method for many smaller inverters now is to 
use a HF drive for the transformer, and use higher voltage semis on the HV 
side to shape the waveform to 60 Hz which yields much less iron and a 
lighter inverter.

Sean Taylor
Urbana, IL