Re: [CAD_CAM_EDM_DRO] 3 Phase drive

Flavio Luiz wrote:

> First of all, Greetings to all on the list!
> It's a pleasure for me to stay here, with some of the "God of the
> knowledgement" in CNC (and more subjects)!. I'm learning a lot with all you.
> A great level list!
> Some time ago I found an interesting explanation about this topic you are
> looking for.
> Try this address, may be is useful to you...
>
> http://perso.infonie.fr/michel50/triphase/triphase_a.htm

Quite impressive for an apparently 'amateur' design, meaning one guy did
it in his basement! But, what I'm looking for is an inverter that can handle
greater than 10:1 speed changes, and frequencies up to 1500 Hz or so.
The PWM patterns pre-programmed for discrete voltage levels into an
EPROM just doesn't cut it, unless you use an awfully big EPROM.
I guess that is certainly an option, now, as 1 MBit EPROMS are pretty
standard devices. I'll have to think about that.

The neat thing about the ML4423 chip is that is would generate CLOSED-LOOP
output voltages 'on the fly', corrcting for any distortions caused by motor
currents, etc. It would also run 1, 2 or 3-phase motors by selecting the
right jumper connection. (Well, a different EPROM pattern would fix that
problem.)

Jon