Phase Winding and Rotating Magnetic Fields — Lesson 3

This lesson covers the concept of 120 Degree Phase Spread Winding Balance Three Phase Winding in electrical machines. It explains how a machine with balanced three-phase winding operates with R, Y, and B phase terminals. The lesson further delves into the concept of time-varying current and how it impacts the magnetic field in the air gap. It also discusses the resultant field due to individual coils and how to calculate it. The lesson concludes with an explanation of the rotating magnetic field, its importance in the functioning of induction and synchronous motors, and how to determine its speed and direction.

Video Highlights

00:36 - Explanation of machine operation with balanced three-phase winding
02:50 - Discussion on time-varying current and its impact on the magnetic field
04:01 - Calculation of the resultant field due to individual coils
09:56 - Understanding the concept of a rotating magnetic field
22:33 - Determining the speed and direction of the rotating magnetic field

Key Takeaways

- A machine with balanced three-phase winding operates with R, Y, and B phase terminals.
- The time-varying current drawn from the supply impacts the magnetic field in the air gap.
- The resultant field at a given position and time can be calculated by adding the fields generated by individual coils.
- The rotating magnetic field is a crucial concept in the functioning of induction and synchronous motors.