kortslutningslindninger

Kortslutningslindninger, often translated as short-circuit windings or squirrel cage windings, are a key component in induction motors. These windings are located in the rotor of the motor and typically consist of conductive bars made of aluminum or copper that are short-circuited at both ends by end rings. This configuration creates a closed electrical circuit within the rotor.

The principle of operation relies on electromagnetic induction. When an alternating current flows through the stator windings, it creates a rotating magnetic field. This rotating magnetic field sweeps across the short-circuit windings of the rotor. According to Faraday's law of induction, this changing magnetic flux induces a voltage and consequently a current in the rotor bars. Because the bars are short-circuited by the end rings, this induced current flows. The interaction between the magnetic field produced by the induced rotor currents and the rotating magnetic field of the stator generates a torque, causing the rotor to rotate.

The "squirrel cage" moniker comes from the appearance of these windings, which resemble the wheel of a hamster or squirrel cage. This design is highly robust and requires minimal maintenance, contributing to the widespread use of induction motors in various industrial and domestic applications. The resistance of the short-circuit windings plays a crucial role in determining the motor's starting torque and speed characteristics. Higher resistance generally leads to higher starting torque but lower efficiency at full speed.