New Design of High Output Equivalent 4-pole Universal Motor

This paper presents a new design of a high output equivalent 4-pole, 2-brush universal motor. Equivalent four poles mean that two poles with field coils are the same poles by changing the connection of two field coils of a 2-pole universal motor and two auxiliary poles without field coils are opposite poles. The 4-pole, 2-brush motor is designed by changing the number of armature slots and the connection of armature coils at the same time. A conventional 2-pole universal motor has been used for the comparison of the motor performance and commutation, where the maximum outer length of a stator is the same with that of the equivalent 4-pole motor. The output of the equivalent 4-pole motor versus the rated voltage and speed was higher than that of the conventional 2-pole motor. The commutation of the equivalent 4-pole universal motor was better than that of the conventional 2-pole motor.