Tuesday, 18 October 2016

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.