Understanding the stepper motor and servo motor

A stepper motor can be referred to as a type of brushless DC motor that divides its full rotation into a number of equal steps and rotates in steps. They have multiple coils organized in phases. The motor will rotate each step at a time as each phase are being energized in sequence.

Basically, stepper motor are of two types:

• Unipolar
• Bipolar

Let’s check them in detail in the following sections.

Unipolar stepper motor

This usually has 6 wires or sometimes 5 wires as shown in following diagram. It has one winding with a center tap per phase:

Figure 4.20 – Unipolar stepper motor

Let’s have a look at Bipolar stepper motor.

Bipolar stepper motor

This usually have 4 wires. It also has one winding per phase but does not have a center tap. They have more torque and are more efficient than unipolar stepper motor:

Figure 4.21 – Bipolar stepper motor

Let’s now learn how to drive a stepper motor.

Driving...