A comprehensive guide: what is a stepper motor

Stepper motor is a kind of component that can convert electrical pulse signals into precise rotating motion. Its working principle is based on the principle of electromagnetism, by controlling the current on and off and direction, so that the rotor of the motor rotates according to the predetermined step Angle. When the stepper driver receives a pulse signal, it drives the stepper motor to rotate at a set fixed Angle (called the "step Angle"). The stepper motor is characterized by accurate position control, because its rotation Angle is proportional to the number of input pulses, and the speed is proportional to the pulse frequency. By controlling the number of pulses, the angular displacement of the stepper motor can be precisely controlled, so as to achieve accurate positioning. At the same time, by controlling the frequency of the pulse, the speed and acceleration of the motor can be controlled, so as to achieve the purpose of controlling the speed.

Working principle of stepper motor

Stepper motor is mainly composed of stator and rotor. The stator has multiple windings, usually two, three or more phases. The rotor is usually composed of multiple magnetic poles, which can be permanent magnets or electromagnets activated by an electric current. When the current passes through the stator's windings, it creates magnetic fields inside the motor, which interact with the magnetic poles on the rotor to produce torque, which drives the rotor to spin.

Structure and type of stepper motor

The structure of the stepper motor usually includes a stator and a rotor. The stator is composed of an iron core and a coil wound around it. When the coil is energized, a magnetic field is generated, which becomes an electromagnet. The rotor is a permanent magnet, and its magnetic field is affected by the stator's magnetic field, which is attracted or repelled, causing the rotor to rotate. In the stepper motor, there are usually two or more groups of coils, corresponding to different magnetic poles. By controlling the power sequence and current size of these coils, you can control the rotation direction and Angle of the rotor.

Stepper motor is a kind of motor that converts electrical pulse signal into mechanical angular displacement, which is widely used in the field of precision positioning and automatic control. The structure types of stepper motor mainly include the following:

Characteristics and performance of stepper motor

Stepper motor is a kind of motor that converts electrical pulse signals into angular displacement or linear displacement. It precisely controls the rotation Angle of the rotor by controlling the sequence of electrification and the number of pulses in the stator windings. Each time a pulse signal is received, the rotor rotates at a fixed step Angle, thus achieving precise position control. Stepper motors usually do not require position feedback systems because their controls are open-loop, but modern stepper motor systems may include position feedback to improve control accuracy.

Firstly, let’s talk about the various characteristics of stepper motor. To make it more simple, we can see the table below.

Secondly, let's look at the excellent performances of the stepper motor.

1. Holding torque. When the stepper motor is energized but not rotated, the stator locks the rotor torque.

2. Pull-in torque: The minimum torque that can overcome the load and maintain stable operation when the stepper motor is started.

3. Out-of-step torque: The torque that the stepper motor can continue to rotate beyond its stable operating range.

4. Step Angle: The Angle of rotation of each pulse signal received by the stepper motor, the smaller the step Angle, the higher the resolution of the motor.

5. No-load starting frequency: the pulse frequency that the stepper motor can start normally under no-load condition.

6. Maximum no-load operating frequency: the highest speed frequency that the stepper motor can achieve without load.

Control methods of stepper motor

In order to operate properly and efficiently, stepper motor will take up different types of control methods, selecting the appropriate mode can optimize the performance of the stepper motor and meet the needs of specific applications. In practical applications, a combination of control strategies may be used to achieve the best control effect.

Practical operation of stepper motor

The wide range of applications of stepper motors demonstrates their importance in modern industry and our daily life, especially where precise control and high dynamic response are required.

For example, a stepper motor is used to control the precise movement of the tool in CNC machine tools to achieve high-precision machining operations.

Besides, stepper motors are also widely applied in automated production lines. On automated assembly and packaging lines, stepper motors control the movement of workbenches, conveyor belts and robotic arms to improve production efficiency and quality.

Moreover, in household appliances, stepper motors are used in electric curtains, electric lifting equipment, etc., to provide smooth and precise control. In devices such as printers, scanners and projectors, stepper motors are used for functions such as accurate paper feed and image adjustment.

In addition to these, the stepper motor is also widely used in other fields, it is like an interesting but mysterious friend of ours, for it can be seen everywhere at any time.

Final Verdict

As an important executive element, stepper motor plays an indispensable role in modern industrial automation and digital control systems. Through in-depth understanding of the basic principles, structural characteristics and control methods of stepper motors, we can make better use of this technology to provide more accurate, efficient and reliable solutions to meet our needs.