Ankarsrum Academy – part 1

Two-pole permanent magnet DC motors – how does it work?


Ankarsrum Electric Motors (AEM) offers a range of mechanically commutated low voltage permanent magnet DC motors with and without transmission. DC motors of this type are commonplace in wire feeders for welding, hospital beds, garage doors, and structural applications.


The AEM DC motors are designed with a two-pole permanent magnet stator and a rotor wound with copper wire. The magnetic field is applied radially and when the current passes through the copper coil, a magnetic field is generated around the armature. The left side of the rotor is pushed away from the left magnet and drawn towards the right-hand side, causing rotation.


When the armature becomes horizontally aligned, the torque becomes zero. At this point, the commutator reverses the direction of current through the coil, reversing the magnetic field.


Then the process is repeated, and the motor rotates.


The speed of the motor is controlled to the voltage applied and the torque is determined by the level of current.