Igor, My servo drives are Yaskawa and it is my understanding that they close the speed and current loops, and EMC2 closes the position loop. It is important that the outside loop (position) be at least, if not more responsive, than the middle loop (speed). Maybe my settings will help you:
EMC2: Max Velocity = .5 Max Acceleration = 10. P = 280 I = 3.5 D = .25 FF0 = .25 Yaskawa: Cn-03 Speed Reference Gain = 1500 AutoTune Rigidity = 4 Cn-04 Speed Loop Gain = 165 Cn-05 Speed Loop Integration Time Constant = 22 Cn- 17 Torque Reference Filter Time Constant = 4 Also, when servo tuning use the maximum velocity and view the velocity profile on Halscope. It took me many, many tries to get these numbers . . . like Las Vegas! Good luck. -----Original Message----- From: Igor Chudov [mailto:[email protected]] Sent: Monday, September 13, 2010 9:37 AM To: Enhanced Machine Controller (EMC) Subject: [Emc-users] Servos cannot calm down -- maybe I should go away from velocity mode in amplifiers? I posted a message to this list that my servo motors cannot calm down after a motion. Right now my amplifiers are set to velocity mode and I use a tachometer for velocity feedback. So, the amps themselves have a velocity loop that they close. There is essentially two loops per axis, one in EMC2 and one in the amplifier. Unfortunately, my efforts to tune PID to calm the mill down, have not been successful. If I turn down the gain parameters, the mill starts getting following errors, if I turn them up, the motors have hard times calming down. If, when the mill cannot calm down, I hit F2 (which for me inhibits the amps), and then F2 again, the bothersome buzzing stops. I am now thinking that I should reconsider my entire approach and use a different mode to avoid two loops per axis. My amplifiers offer the following modes: 1) Velocity (tachometer) mode, which is the current setting 2) Current or Torque mode (amplifier controls torque/current) 3) Voltage mode (amplifier maintains voltage) 4) IR compensation (not sure what it is exactly, probably compensated for resistance losses in windings). So... Would you think that I should switch to, say, torque mode or voltage mode? Any thoughts? - Igor ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users This communication is for the use of the intended recipient only. It may contain information that is privileged and confidential. If you are not the intended recipient of this communication, the disclosure, copying, distribution or use hereof is prohibited. If you have received this communication in error, please advise me by return e-mail or by telephone and then delete it immediately. ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
