A brief explanation of stepper motors, you will understand after reading it
Stepper motors, as executive components, are one of the key products of mechatronics integration and are widely used in various automation control systems. With the development of microelectronics and computer technology, the demand for stepper motors is increasing day by day, and they have applications in various fields of the national economy. As an electrician, one should not only have a limited understanding of stepper motors, but also have a deep understanding of their structure, basic principles, and applications.

What is a stepper motor?

A stepper motor is an electromechanical device that directly converts electrical pulses into mechanical motion. By controlling the sequence, frequency, and quantity of electrical pulses applied to the motor coils, the steering, speed, and rotation angle of the stepper motor can be controlled. Without relying on a closed-loop feedback control system with position sensing, a simple and low-cost open-loop control system composed of a stepper motor and its accompanying driver can achieve precise position and speed control.

Basic structure

·Stator: It is usually composed of multiple magnetic poles with excitation windings wound around them. By applying currents of different sequences and sizes to the excitation winding, different magnetic fields will be generated.

·Rotor: It is the rotating part of a motor with teeth or magnetic poles on it. The teeth or magnetic poles of the rotor interact with the magnetic poles of the stator, generating torque under the action of the stator magnetic field, thereby causing the rotor to rotate.

Working principle

The working principle of stepper motors is based on electromagnetics. The current passes through the electromagnetic coil of the stator, generating a magnetic field. This magnetic field interacts with the permanent magnets on the rotor, causing the rotor to rotate by a certain step angle. The control circuit sends a series of pulse signals to the motor, each corresponding to a step angle, to control the rotation of the motor. The term 'stepper' refers to a motor moving at a fixed step angle. A stepper motor drives the rotor to rotate at a certain step angle by controlling pulse signals.

Characteristics of stepper motors

1. Accuracy

Stepper motors can rotate at a fixed step angle, providing relatively high position control accuracy.

2. Simple control

Controlling a stepper motor only requires sending pulse signals, which is relatively simple to control and suitable for open-loop systems.

3. Zero speed torque

In the stopped state, the stepper motor can maintain a certain torque without the need for additional mechanical locking.

4. Low speed and high torque

At low speeds, stepper motors typically have high torque, making them suitable for applications that require high torque but low speed.

4. Brushless and frictionless

Due to the brushless design, stepper motors do not require brushes, reducing friction and wear.