How does a stepper motor move?

A stepper motor is a type of brushless DC motor that is used for precision control of motion. Unlike a traditional DC motor, a stepper motor moves in discrete steps rather than continuously. The movement of the stepper motor is controlled by electrical pulses sent to the motor's windings.

There are two main types of stepper motors: the permanent magnet stepper motor and the hybrid stepper motor. The permanent magnet stepper motor has a permanent magnet rotor and a stator made up of two windings. When an electrical pulse is sent to one of the windings, the magnetic field produced causes the rotor to align itself with the stator. When the pulse is removed and sent to the other winding, the rotor moves to align with that winding. This process continues as the electrical pulses alternate between the two windings, causing the rotor to move in discrete steps.

The hybrid stepper motor is more complex than the permanent magnet stepper motor and has a more precise movement. It has a rotor made up of a permanent magnet and a stator with multiple windings. When an electrical pulse is sent to one of the windings, the rotor aligns itself with that winding. However, before the pulse is removed, a smaller electrical pulse is sent to an adjacent winding, causing the rotor to move slightly in that direction. This process is repeated for each winding, resulting in very precise movement of the rotor.

The number of steps a stepper motor can take per revolution is determined by the number of teeth on the rotor and the number of poles on the stator. The more teeth and poles, the more steps the motor can take per revolution. Stepper motors can be controlled by microprocessors, which send electrical pulses to the motor to control its movement.

In summary, a stepper motor moves in discrete steps rather than continuously, and its movement is controlled by electrical pulses sent to its windings. The two main types of stepper motors are the permanent magnet stepper motor and the hybrid stepper motor, which offer different levels of precision in their movement.