On Thu, 2012-01-12 at 13:49 +0200, Viesturs Lācis wrote: ... snip > How big was that motor? Should something be differently with AC servo > motor? I am not sure anymore that I do understand, what is inside AC > servo motor. Normal DC brushless motors have permanent magnets, but I > have difficulties understanding, how AC servo drives work (the fact > that it still supplies DC to motors is confusing me), so I am not sure > anymore that AC servo motors are synchronous electrical motors > with permanent magnets. ... snip
My understanding is that AC and DC brushless motors have nearly the same construction, being a multi pole permanent magnet rotor and three phase wound outer stator. The difference is in the details of the magnetic shape between the stator and rotor. The result is an AC brushless motor will give close to constant torque output from a constant (non-feedback) sinusoidal AC input. A DC motor will output close to a constant torque with a step or trapezoidal or DC input. Since, with EMC2, we are interested in tight feedback control, AC or DC motors will give close to the same result. So, AC or DC motors should work well enough and the feedback should provide the proper input. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ RSA(R) Conference 2012 Mar 27 - Feb 2 Save $400 by Jan. 27 Register now! http://p.sf.net/sfu/rsa-sfdev2dev2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
