Electric motors convert electrical energy into mechanical motion and are broadly classified into two different categories: DC (Direct Current) and AC (Alternating Current). Within these categories are numerous types, each offering unique abilities that suit them well for specific applications. In most cases, regardless of type, electric motors consist of a stator (stationary field) and a rotor (the rotating field or armature) and operate through the interaction of magnetic flux and electric current to produce rotational speed and torque.
Electric motors are divided into three broad horsepower (hp) categories: small, medium and large. The most common motors are considered to be fractional-horsepower motors with ratings from 1/20 to 1 hp and are categorized as small motors. Also included in the small category are motors with smaller ratings, which are commonly classified as sub-fractional or miniature. Medium size motors are considered to be in the range of 1 hp through 100 hp, with large motors occupying the 100 hp to 50,000 hp range. Categories can vary due to motor type (AC or DC), speed, number of poles and maximum ratings.
By Dave Wilson, Cirrus Logic I have observed that humans are generally underdamped creatures. When excited with a step function change, we often overreact before settling in to a proper response. In the 90’s, the step function was “DSP”. You may recall the frenzy to drop DSPs into everything, if for no other reason than to put a colorful label on your product to boast it...
