If it meets your needs then you have succeeded. :-) I have put AC servos on Induction Hardening machines before. The machine you are using may be similar to the one I automated. The shaft/camshaft moves vertically through an energized induction coil and is sprayed with water to create harden the surface. I put a high dollar Parker servo on one years ago and the drive went crazy when the induction coils were energized. We tried everything and ended up putting in a much cheaper AC servo drive and the problems went away. :-) The induction coils induce voltage into everything that is near the them, including cables, motors, etc. The machine frame "ground" varies in potential along the machine frame.
If you have a similar machine, then .3-.4 mm of error is quite acceptable. Dave On 12/11/2013 1:36 PM, Leonardo Marsaglia wrote: > Well. As you say it's not the best to use an induction AC motor for a servo > work but I managed to get 0.3 or 0.4 mm of error wich is pretty cool for > the job. > > I tried using the pid BIAS as Andy told to decrease vibration but nothing > happened. Also tried decreasing the servo thread speed as Gene said but > didn't help either. > > I think the best here is to avoid the resonance speed as Jon told, because > if I increase the rapid to 9000 mm/min (wich is a lot) I have a lot less > vibration. This happens also when I decrease it to 1500 mm/min. > > I guess with a better tuning I can get better results but I have a lot to > learn about servos, also there's the inherent limitation of the AC motor. > But I don't have to forget that the charriot it's vertical and weights a > lot, we even tried with a person standing over it and behaves in the same > way so it will work ok with the induction transformer that has to be on it. > > I'm happy because it's going to work really fine for the job, most of you > already know that I was automating a machine for case hardening on > camshafts. And may be in the near future I can install an AC servo since > this VFD can handle permanent magnet motors too. > > In the next few days I'll be uploading some videos to show you how it works > and how is the machine. Also I would like you to see it fully working with > the induction heater on it! > > Thanks as alway!! > > > > > 2013/12/11 Kirk Wallace <kwall...@wallacecompany.com> > >> On 12/11/2013 09:40 AM, Dave Cole wrote: >> ... snip >>> Siemens had hybrid motors that were not >>> standard induction motors at the time that could do better positioning >>> but they were as expensive ore more expensive than other companies servo >>> drive systems and were generally only used for very large HP/torque >>> applications that required some level of positioning at high power >>> levels. Think big $$. >>> >>> Dave >> Speaking of getting creative with induction motors, I found this >> recently. It may be of interest. >> >> http://powerelectronics.com/power-management/how-run-split-phase-induction-motor-three-phase-inverter >> >> >> -- >> Kirk Wallace >> http://www.wallacecompany.com/machine_shop/ >> http://www.wallacecompany.com/E45/ >> >> >> ------------------------------------------------------------------------------ >> Rapidly troubleshoot problems before they affect your business. Most IT >> organizations don't have a clear picture of how application performance >> affects their revenue. With AppDynamics, you get 100% visibility into your >> Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics >> Pro! >> http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > > ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
