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How are magnets used in electric motors and generators?

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Learn about magnetic fields and the levels of particles, atoms, crystals, and domains — magnet Magnetic fields and the levels of magnetism of particles, atoms, crystals, and domains.

Magnets are fundamental to the operation of both electric motors and generators, serving as the source of the magnetic fields necessary for energy conversion.1

Electric Motors

Electric motors convert electrical energy into mechanical energy. Most motors function through the interaction between a magnetic field and conductors carrying an electric current. When current flows through these conductors at right angles to the magnetic field, a mechanical force is generated, producing torque. While many industrial motors use electromagnets made of soft iron or silicon-iron to achieve high flux densities, permanent-magnet motors—which utilize materials like neodymium-boron-iron or samarium-cobalt—are increasingly common in applications requiring high efficiency and precise control, such as variable-speed drives.231

Electric Generators

Generators operate on the inverse principle of motors: they convert mechanical energy into electrical energy through electromagnetic induction. By moving a conductor through a magnetic field, an electromotive force is induced in the circuit. Similar to motors, generators can utilize either electromagnets or permanent magnets to provide the necessary magnetic field. Permanent-magnet generators are valued for their simplicity and reliability, as they do not require a separate system to provide field current, making them ideal for applications like wind turbines.4156