How Stepper Motor Works?? | Electrical Machine Theory

Here we provided theory of stepper motor and also explain it's working principle and how stepper motor works, this theory is more useful for learning in electrical machine theory.

Stepper Motor

A stepper motor is an incremental motion machine or the motor which turns in discrete movement called the step.

It does not rotate continuously as a conventional motor does.

The stepper motor is a special type of synchronous motor which is designed to rotate through a specific number of degrees for each electrical pulse received by its control unit.

Typical steps are 20, 2.5 ,5 ,7.5 and 15 per pulse. These motors are built to follow signals as rapid as 1200 pulses per second and with equivalent power ratings up to several kW.

The stepper motor is used in digitally controlled position control system in open loop mode.

The input command is in the form of a train of pulses to turn a shaft through a specified angel.

Advantages of stepper Motor:

The stepper motor is having the following advantages:

Compatibility with digital systems.

The angular displacement can be precisely

controlled without any feedback arrangement.

No sensors are needed for position and speed sensing.

It can be readily interfaced with microprocessor or computer based microcontroller.

Stepper Motor Types :

There are three main types of stepper motor types,

Permanent magnet stepper
Hybrid synchronous stepper
Variable reluctance stepper

Applications of Stepper Motor:

Stepper motors have a many applications, which is mentioned below:

✓Paper feed motors in typewriters and printers.
✓Positioning of print heads.
✓Pens in XY-plotters.
✓Recording heads in computer disc drives.
✓Positioning of worktables and tools in numerically controlled machining equipment.
✓Also employed to perform many other functions such as metering, mixing; cutting, blending, stirring etc. in several commercial, military and medical applications.