Problem with wound rotor of old motor

Discussion in 'General Electronics Chat' started by pafkatata, Dec 1, 2011.

  1. pafkatata

    Thread Starter New Member

    Dec 1, 2011
    3
    0
    Hello,
    I have problem with an old asynchronous motor with wound rotor it is VEB MEZ VSTEIN.I am intending to run the motor via frequency inverter by connecting it to the stator windings. I need to short circuit the rotor, but there are 6 poles coming out (a,b,c and a0,b0,c0) from the wound rotor collector and I don’t know which one to connect to which. Can you help me with advice?
    Thank you
     
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    Last edited: Dec 1, 2011
  2. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    6,357
    718
    125 HP motor @ 300A

    It's interesting, I'll bump this as I don't know of a good way, it nearly looks like a giant stepper motor. :D
     
  3. pafkatata

    Thread Starter New Member

    Dec 1, 2011
    3
    0
    Yes it is quite huge motor it is in a testing facility. I t is rotating a big fan in a tunnel and its purpose is to simulate a wind with a particular speed.But the guys want to get rid of this old scheme connection and want to control it via frequency converter. Actually i did this but with a normal asynchronous motor with wound rotor with only 3 poles on the rotor which i had to get short circuit them to each other, but this monster has 6 poles as you can see on the scheme (maybe 3 for the beginning and 3 for the end of the rotor winds).
     
  4. shortbus

    AAC Fanatic!

    Sep 30, 2009
    4,015
    1,531
    I think that type motor is often know as a 'Heyland' motor. From your schematic it looks to have 'compensating' brushes, to cut down on sparking on the commutator.

    This type motor is used in place of a frequency converter to control its speed. The voltage and frequency on the commutator is what controls the speed. couldn't find any information on if they can be run with a VFD. You should check with the manufacturer of the VFD to see if it can be used with this type motor. Some old motors don't take to use with a VFD due to the insulation of the wire in the stator and rotor.

    The commutator on this type of motor is also some times used with switched resistance to cut down on current draw at start up.
     
    strantor likes this.
  5. pafkatata

    Thread Starter New Member

    Dec 1, 2011
    3
    0
    Thank you for the info, but the bottom line is what to do with these 6 poles coming out (a,b,c and a0,b0,c0) from the wound rotor collector?
     
  6. GetDeviceInfo

    Senior Member

    Jun 7, 2009
    1,571
    230
    Very cool stuff;

    your print doesn't show if you have an external starting motor. I'd be placing the inverter on your mainline, to include the exciter, synchronous, and starting motor if you have one. I'm thinking you'd only short your field if you have induction start, but your variable frequency may well perform an adequate start on it's own.
     
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