When commutation occurs in a DC motor with multiple windings, why isn't there a voltage spike across the disconnected windings? How is the inductance of the winding addressed?
The windings are not actually disconnected. The commutator segments are connected to points along a continuous winding. In moving from one segment to the next, the brushes essentially move sections of the armature winding from one current path to a parallel current path. With each transition, the current is reversed in only a section of the armature. There are voltage spikes and some arcing, but it is not as dramatic as it would be for opening an inductive circuit.