On Fri, 11 Jun 2010 15:35 +0100, "Andy Pugh" <[email protected]> wrote: > On 11 June 2010 14:53, Jeff Epler <[email protected]> wrote: > > Ignore the code, I need to take a course in remedial-level git and dif. > > > I am still concerned about 'dir'. I see that if angle is 90 that > > negating value or inverting dir do the same thing, but for other values > > of angle this isn't true. For instance, if 'angle' is 60 and you try to > > invert the rotational direction by having a negative 'value' and not > > changing 'dir' then you'll get an effective theta of -120 when the > > desired is -60. > > I agree, I can't see it any other way. > > But... reversing the polarity of the motor terminals of a permanent > magnet motor always reverses the motor, as far as I know. Sending a > negated voltage pattern to the 3-phase PWM produces the inverse > gate-drive voltages, which I think is exactly the same as a polarity > switch.
I haven't taken the time to read the code in detail, so I might be confused. But I don't think inverting all three phase signals will reverse the motor. The normal way of reversing a three phase motor when running across the line is to swap any TWO of the three phase wires. That will reverse the phase rotation. I think you want to reverse the angle. > I am pretty sure that I prefer the approach of swapping the lead angle > though, and intend to make that change if I ever trust myself near a > computer again after this diff-posting debacle. Isn't this a brand new component? Spare yourself the pain of making the diff (and us the pain of reading it). Just post the component itself. Diff's are great when discussing a small change in the context of a large body of code. They suck when talking about code that is totally (or even mostly) new. Just my $0.02 John Kasunich -- John Kasunich [email protected] ------------------------------------------------------------------------------ ThinkGeek and WIRED's GeekDad team up for the Ultimate GeekDad Father's Day Giveaway. ONE MASSIVE PRIZE to the lucky parental unit. See the prize list and enter to win: http://p.sf.net/sfu/thinkgeek-promo _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
