There are various types of best stepper motors, divided into linear or rotational constructions, with 1 to 5 control windings.
Based on the constructi
Variable reluctance – reactive type;
Permanent magnet – active type;
Hybrid.
Variable reluctance (VR) stepper motors have uniformly distributed teeth, made of iron, on both the stator and the rotor, control windings being mounted on the stator’s teeth, while the rotor is passive. By energizing one or more phases, the rotor will turn in such manner that the magnetic field lines should follow a minimum reluctance path, i.e. the rotor’s teeth must align themselves either with the teeth on the stator, or with the bisectrix of the stator’s electromagnetic poles.
Permanent magnet (PM) stepper motors have a different construction, here the teeth on the rotor are made of permanent magnet material with poles set up in a radial fashion, the stator construction being similar. When the stator windings are energized, magnetic fields that are generated interact with the PM’s flux, generating torque to move the rotor.
Stepper motors have power ratings ranging from the Microwatt domain to not exceeding a few Kilowatts, thus being preferred in low to medium power applications, where precision high-speed movement is required, rather than in heavy duty applications where torque is a key factor. These motors employed in plotters, disc drives, printers, robotic arms, CNC machines and others of the type.
Hybrid stepper motors for sale represent a combination of the other two types, and are the most common type of stepper motors employed. In a hybrid stepper, the rotor is made from a permanent magnet, mounted length-wise, with two ferromagnetic toothed crowns, mounted at both ends of the magnet, so that the teeth of one crown are north poles and the ones on the other crown are south poles.
