elektromotorrotors

An electromotor rotor is the rotating part of an electric motor. Working together with the stator, the rotor converts electrical energy into mechanical energy by responding to the stator’s rotating magnetic field. The rotor’s behavior is governed by the machine type, construction, and operating conditions.

Most alternating-current (AC) motors use a rotor of two main kinds. The squirrel-cage rotor, the most common, consists of a laminated iron core with conducting bars shorted at the ends by end rings. The bars form a low-impedance path for currents induced by the stator field, producing torque. Wound-rotor motors have windings on the rotor connected through slip rings to an external circuit; this allows resistance insertion and control of starting torque and speed.

In DC motors, the rotor, or armature, carries windings connected to a commutator and brushes to reverse current as the shaft turns. In synchronous machines, rotors are either salient-pole wound rotors excited by DC or permanent-magnet rotors that lock with the stator field to run at synchronous speed.

Construction features: rotors are built from laminated steel to minimize eddy currents, with slots to carry windings. They include a shaft, bearings, and often a cooling fan. In high-power applications, rotor design influences efficiency, starting torque, wear, and heat dissipation.

Operation and performance: torque is produced by the interaction of rotor currents with the stator field. In induction motors, slip—the difference between synchronous and rotor speeds—controls torque and speed. Rotor health affects reliability; common issues include bearing wear, shaft misalignment, and rotor bar damage.

Applications: rotors appear in nearly all electric motors used for industrial machinery, household appliances, and transportation. Ongoing advances focus on materials, cooling, and control strategies to improve efficiency and dynamic response.