Resistor Split in Single Phase Induction Motors — Lesson 4

This lesson covers the concept of starting torque in single phase induction motors. It explains the role of the main and auxiliary windings in the motor and how they are connected in parallel. The lesson also discusses the importance of the number of turns in these windings and how they affect the starting torque. It further elaborates on the concept of phase splitting and how it can be achieved through resistor splitting or capacitor splitting. The lesson also touches upon the concept of a centrifugal switch and its role in disconnecting the auxiliary winding when the motor reaches close to synchronous speed. Towards the end, the lesson discusses how to choose the optimum value for external resistance or capacitance to maximize the starting torque.

Video Highlights

00:58 - Discussion on the number of turns in windings
03:02 - Concept of phase splitting
13:00 - Role of a centrifugal switch
28:25 - Choosing optimum value for external resistance or capacitance

Key Takeaways

- The starting torque in a single phase induction motor is influenced by the number of turns in the main and auxiliary windings.
- Phase splitting, achieved through resistor or capacitor splitting, is a method used to create a difference between the power factor angles of the main and auxiliary windings.
- A centrifugal switch is used to disconnect the auxiliary winding when the motor reaches close to synchronous speed.
- The optimum value for external resistance or capacitance, which maximizes the starting torque, can be determined based on the starting and running performance of the motor.