Re: [CAD_CAM_EDM_DRO] 5-Phase steppers

Well - I did a little Googling and found this paper:
http://ee.tamu.edu/~empelab/power_tran98.pdf

It's an electrical/mathematical analysis of a 5-phase stepper, so all
the information is in there. I didn't want to slog through the math,
but I did look at the drive waveforms (on page 2, with a drive
pseudo-circuit). Basically, there should be 5 wires coming from the
motor. The drive system they analyze has 10 steps per electrical
cycle. Each phase can be connected to +V or -V at any time - note that
"disconnected" isn't an option. Essentially, the 5 phases (A-E) are
each connectd to +V for 5 periods, then to -V for 5 periods. The phases
are staggered by two periods each.

So, given 10 "steps" per electrical cycle, the phases are energized like
this:
Phase A B C D E
period
1 + - - + +
2 + - - - +
3 + + - - +
4 + + - - -
5 + + + - -
6 - + + - -
7 - + + + -
8 - - + + -
9 - - + + +
10 - - - + +

I think the 10-step mode is actually a "half-stepping" mode, so this
might give 1000 steps per revolution instead of 500.

If someone sends me a circuit diagram, I can lay out a board and write
some PIC or AVR code for it. (I'm an electrical engineer, but I've
always been more comfortable with the digital design/programming end,
not the power end of things :)

- Steve

Peter Barrett wrote:

>I'm still looking for some sources of information on the 5-phase stepper
>motor, their care and feeding.
>
>Online info is hard to come by, The only stuff I have found is in the
>Douglas Jones tutorial.
>
>If anyone has some circuits, logic diags, PIC code or anything else I
>would love to see.
>
>PeterB
>Beckenham
>