Those sites are interesting, but it seems to me they still intend to use them as traction motors, as that what series motors are used for, and are just allowing some control of speed. I would question as to wether they would be usefull used in normal servo use, as the field is still in series with the armature and as such I would think the control will not be precise. DC servo motors of all sizes, typically have a shunt field, wether Wound or Permanant magnet, whereby the field strength is known and is constant.
Maybe someone here has done this and may be able to shed some more light.
Al
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CNC, Mechatronics Integration and Machine Design.
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E. |