Circuit Analysis II with MATLAB Applications
Designed for use in a second course in circuit analysis, this text engages a full spectrum of circuit analysis related subjects ranging from the most abstract to the most practical.
TABLE OF CONTENTS Circuit Analysis II with MATLAB Applications
Chapter 8: Self and Mutual Inductances - Transformers
This chapter begins with the interactions between electric circuits and changing magnetic fields. It defines self and mutual inductances, flux linkages, induced voltages, the dot convention, Lenz's law, and magnetic coupling. It concludes with a detailed discussion on transformers.
8.1 Self-Inductance
About 1830, Joseph Henry, while working at the university which is now known as Princeton, found that electric current flowing in a circuit has a property analogous to mechanical momentum which is a measure of the motion of a body and it is equal to the product of its mass and velocity, i.e., Mv. In electric circuits this property is sometimes referred to as the electrokinetic momentum and it is equal to the product of Li where i is the current analogous to velocity and the self-inductance L is analogous to the mass M. About the same time, Michael Faraday visualized this property in a magnetic field in space around a current carrying conductor. This electrokinetic momentum is denoted by the symbol ?, that is,
Newton's second law states that the force necessary to change the velocity of a body with mass M is equal to the rate of change of the momentum, i.e.,
where a is the acceleration. The analogous electrical relation says that the voltage v necessary to produce a change of current in an inductive circuit is equal to the rate of change of electrokinetic momentum, i.e,
8.2 The Nature of Inductance
Inductance is associated with...
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