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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?

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  • \$\begingroup\$ There is an inductive kick. Easily demonstrated in brushless DC motors where the brushes have been replaced by electronics and measures must be taken to handle the voltage spikes. If I remember right, that's why in brushed motors, brush resistance and/or the fact the brushes might overlap windings a bit is desirable. electronics.stackexchange.com/questions/296118/… There is another question like this on here that is answered. I'll try to find it. \$\endgroup\$
    – DKNguyen
    Oct 15 '21 at 21:46
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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.

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