Inductance in Salient Pole Machine - I — Lesson 2

This lesson covers expressions for inductance in salient rotor machine with cylindrical stator and a salient rotor. It explains the concept of self-inductance and mutual inductance, and how these vary with the rotor angle in different machine configurations. The lesson also discusses the impact of the rotor's position on the flux density and inductance of the stator and rotor coils. It further illustrates these concepts with the help of Finite Element Method (FEM) simulation studies. The lesson concludes with an explanation of how to estimate the value of mutual inductance.

Video Highlights

00:11 - Introduction
02:00 - Explanation of the rotor angle and its impact on the mutual inductance
07:07 - Explanation of the geometry of a machine with a cylindrical stator and a salient rotor
08:57 - Discussion on the non-uniform air gap in salient pole machines and how to derive expressions for inductance in such a machine
11:14 - Explanation of how to determine the self inductance of the rotor and the stator, and the mutual inductance
15:30 - Discussion on the impact of the rotor position on the flux levels and inductance
17:00 - Explanation of the FEM simulation study showing how flux lines are generated for the rotor aligned horizontally
40:03 - Discussion on the impact of the rotor rotation on the flux density pattern around the air gap

Key Takeaways

- The self-inductance of the stator coil and rotor coil in a machine does not vary with the rotor angle.
- The mutual inductance between the stator and rotor coil is a function of the rotor angle.
- The flux density and inductance of the stator and rotor coils depend on the rotor's position.
- The value of mutual inductance can be estimated using the flux density waveform and the rotor's position.