single-phase induction motor
Quick Summary
Single-phase induction motors are commonly used in domestic and commercial settings where only single-phase power is available. Unlike three-phase motors, they require a special mechanism to create a rotating magnetic field for starting.
Several methods are employed to achieve this:
- Split-phase motors use two stator windings. An auxiliary winding, with higher resistance, causes its current to lead the main winding's current, creating a starting torque. This winding is disconnected once the motor reaches a certain speed.1
- Capacitor induction motors also use two stator windings, but the auxiliary winding is connected through a capacitor. This capacitor shifts the current phase by approximately 90 degrees, generating a strong rotating field and high starting torque, making them suitable for heavy-duty applications.2
- Shaded-pole motors have a short-circuited "shading coil" around a portion of the main winding. This coil delays the magnetic flux, producing a weak rotating field and low starting torque, making them ideal for low-torque loads like small fans.3
Summary created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
3 Britannica Sources
Ask Britannica AI about this topic
Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.
