Modeling of electromechanical and electromagnetic disturbances in DC motors

Electromechanical and electromagnetic disturbances produced by DC motors were modeled using a dynamic electrical network representation that includes a representation of the changing circuit configuration due to the commutation. With this technique the instantaneous current and voltage of each of the armature coils of the motor are computed as is the instantaneous electromagnetic torque developed by the motor. This tensor-based network model generates inputs to a set of state equations describing the electromagnetic and electromechanical behavior of the motor. The output can be used to study sources of noise and vibration in addition to performance characteristics for DC motors. Using this model, the effects of manufacturing tolerances in the assembly of motors can be evaluated. The tensor-based method is used to simulate time-varying circuit topology of the armature winding of a DC motor. Some numerical results comparing the predicted with the measured waveforms of a sample three-brush DC motor are discussed