Reluctance motor

Cross-section of switched reluctance machine with 6 stator and 4 rotor poles. Notice the concentrated windings on the stator poles.
Cross-section of switched reluctance machine with 6 stator and 4 rotor poles. Notice the concentrated windings on the stator poles.

A reluctance motor is a type of electric motor that induces non-permanent magnetic poles on the ferromagnetic rotor. The rotor does not have any windings. It generates torque through magnetic reluctance.

Reluctance motor subtypes include synchronous, variable, switched and variable stepping.

Reluctance motors can deliver high power density at low cost, making them attractive for many applications. Disadvantages include high torque ripple (the difference between maximum and minimum torque during one revolution) when operated at low speed, and noise due to torque ripple.[1]

Until the early twenty-first century, their use was limited by the complexity of designing and controlling them.[disputeddiscuss] Advances in theory, computer design tools, and low-cost embedded systems for control overcame these obstacles. Microcontrollers use real-time computing control algorithms to tailor drive waveforms according to rotor position and current/voltage feedback. Before the development of large-scale integrated circuits, the control electronics were prohibitively costly.

  1. ^ "Acoustic noise in home appliances due to torque ripple in motor drives – part 1 - Motor Drive & Control - Blogs - TI E2E Community". e2e.ti.com. Retrieved 2019-04-09.