The series wound DC motor has always prevalently used for traction motors, due to the high constant torque/high current capability.
Your automotive starter motor for instance is a series field wound motor, they should never be used without load due to the runaway condition that is possible, This is similar to Universal router motors where the maximum rpm is limited by the friction and fan windage etc.
With PM motors, the concern is demagnetization at high stator currents.
Here is a 'little' recent contract retro-fit of ours to traction motor dynamic braking to allow the use in the Canadian Rockies.
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.
Last edited by Al_The_Man; 08-13-2009 at 07:31 PM.
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