In resistance commutation method we add resistance between __________________(a) Brushes and external circuit(b) Commutator and armature winding(c) At field winding(d) Commutator and brushThe question was posed to me in my homework.Question is from Commutation Process -1 in chapter Commutation Process & Excitation Methods of DC Machines

In resistance commutation method we add resistance between ___________

1.	In resistance commutation method we add resistance between __________________(a) Brushes and external circuit(b) Commutator and armature winding(c) At field winding(d) Commutator and brushThe question was posed to me in my homework.Question is from Commutation Process -1 in chapter Commutation Process & Excitation Methods of DC Machines
Answer» Correct ANSWER is (d) Commutator and brush The explanation: High contact resistance between commutator segments and BRUSHES, achieved by using carbon brushes, adds resistance to the CIRCUIT of the commutating coil thereby REDUCING the time constant (L/R) of the current transient (ic(t)), helping it to change faster in the desired direction.

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