e-Learning in electrical engineering

Search | Navigation principles
Electromagnetic conversion Rotating field machines Synchronous machine Asynchronous machine MCQs

6. Analogy between magnetic circuits/electrical circuits

Lecture's plan

Introduction

  1. The importance of the magnetic circuit notion
  2. An example of magnetic circuit
  3. Defining the integration contour for the application of Ampère's theorem
  4. The application of Ampère's theorem - emphasizing the magnetic circuit
  5. Hopkinson's law
  6. Analogy between magnetic circuits/electrical circuits
  7. Application for modelling an electromechanical converter
  8. Defining the equivalent magnetic circuit
  9. The reduction of the equivalent magnetic circuit
  10. Flux-current relation
  11. The calculus of the magnetic co-energy and attraction force

Analogies between magnetic circuits and electrical circuits are easy to be made:

  • The magnetic flux which flows through a magnetic circuit, corresponds to the electrical current / which flows through an electrical circuit;
  • the magnetomotive force F, corresponds to the electromotive force U;
  • reluctance R of a magnetic conductor by lenght, S section and permeability, corresponds to resistance R of an electrical conductor by lenght, S section and conductivity; we can write R = şi R = ;
  • finally Hopkison's Law F = R. corresponds to Ohm's Law U = R.I.

We can also define the permeance of a magnetic circuit P = 1/R, which corresponds to G = 1/R conductance of an electrical circuit.

Magnetic circuit
Electrical circuit
Flux (y) Current (I)
Magnetomotive force(F) Electromotive force (U)
Reluctance (R) Resistance (R)
Permeance (P) Conductance (G)
Hopkison's Law (F = R.y) Ohm's Law (U = R.I)

Analogy magnetic circuits / electrical circuits

Site coordinator: Damien Grenier | Realization: Sophie Labrique | © e-lee.net
Last update: 2005, September, 30 | Translation: Sergiu Ivanov | Realization: Florin Ravigan, Cristian Vladu