A rotary electromechanical device that converts direct current electrical energy into mechanical energy (a motor) or vice versa (a generator) relies on stationary permanent magnets to create the magnetic field, eliminating the need for field windings and the associated current or power losses. Common examples include small motors used in appliances, automobiles, and robotics, as well as larger generators in some wind turbines.
This configuration offers several advantages, including higher efficiency due to the absence of field winding losses, simpler construction, and smaller size for a given power output compared to machines employing electromagnets. These benefits have driven their widespread adoption in various applications since the development of high-strength permanent magnets. The technology continues to advance, with ongoing research and development focusing on improved materials and designs to further enhance performance and reduce cost.
