Notes : DCMT module 2 & 3 complete note

Module 2 & 3 : DC generators motors

Module notes prepared by
Nimisha Ravi
Asst. Prof of EEE Dept.

Thanks to giving wonderful notes

Sample content

DC GENERATOR-Principle of operation

D.C generator is a machine that converts mechanical

energy into DC electrical energy. Generator is based on the

principle that whenever a magnetic flux is cut by a moving

conductor a dynamic emf is induced in the conductor, as per

Faraday’s laws of electromagnetic induction. The emf so

induced is an alternating emf. It is made unidirectional with the

help of commutator and brushes. This emf causes flow of current

in the external circuit if the circuit is closed. The direction of this

induced emf is given by Fleming’s right hand rule. According

to this rule, if the middle finger, forefinger and thumb of right

hand are at right angle to each other and if the forefinger

represent the direction of magnetic field and the direction of

motion respectively, then the middle finger will indicate the

direction of the induced emf.