"Version: 20191201"--Title page verso.Includes bibliographical references.1. The magnetic circuit -- 1.1. Some magnetic properties of the material -- 1.2. The basis for the linear magnetic circuit -- 1.3. The real world -- 1.4. Air-gap in a magnetic structure -- 1.5. Axisymmetric geometry -- 1.6. The permanent magnet -- 1.7. The inductance -- 1.8. Summary2. The non-linear magnetic circuit -- 2.…