What Is Stepper Motor? How It’s Working -Wiring-And Applications
WHAT IS A STEPPER MOTOR ?
- A Stepper Motor, also known as step motor or stepping motor, is a brushless DC electric motor that divides a full rotation into a number of equal steps.
- A standard motor will have a step angle of 1.8 degrees with 200 steps per revoultion.
TYPES OF STEPPER MOTORs
- Variable- reluctance (VR) motor
- Permanent magnet motor
- Hybrid motor
VARIABLE- RELUCTANCE (VR) MOTOR: have a plain iron rotor and operate based on the principle that minimum reluctance occurs with minimum gap, the rotor points are attracted toward the stator magnet poles.
PERMANENT MAGNET MOTOR: use a permanent magnet (PM) in the rotor and operate on the attraction or repulsion between the rotor permanent magnet and the stator electromagnets.
HYBRID MOTOR: They use a combination of permanent magnet and variable reluctance techniques to achieve maximum power in a small package size.
WORKING OF STEPPER MOTOR
As all with electric motors, stepper motors have a stationary part ( the stator ) and a moving part (the rotor).on the stator, there are teeth on which coils are wired, while the rotor is either a permanent magnet or a variable reluctance iron core.
By energizing one or more of the stator Phases, a magnetic field is generated by the current flowing in the coil and the rotor aligns with this field.In the beginning, coil A is energizing and the rotor is aligned with the magnetic field it produces. When coil B is energized, the rotor clockwise by 60 degrees to align with the new magnetic field. the same happens when coil C is energized. In the pictures, the colours of the stator teeth indicate the direction of the magnetic field generated by the stator winding.
APPLICATIONS OF STEPPER MOTOR
- The Stepper motor is used for precious positioning with a motor like hard disk drives, robotics, telescopes and some toys.
- Industrial machines- stepper motors are used in automative gauge and machine tooling automated production equipment.
- Security- new surveillance products for the security industry.
- Medical- stepper motors are used inside scanner,sampler and also found inside degitial dental photography.