1.Working principle
1.Two-phase stepper motors
Two-phase stepper motors refer to motors whose drive circuits have only two inputs, each of which controls a coil. When this motor rotates, one coil is activated first to generate a magnetic field, and then the other coil is activated to generate a magnetic field, thereby driving the motor to rotate. Two-phase stepper motors are usually simpler and easier to control, but because there are only two inputs, the step angle cannot be subdivided.
2.Four-phase stepper motors
Four-phase stepper motors refer to motors whose drive circuits have four inputs, each of which controls a coil. When this motor rotates, two coils are activated first to generate a magnetic field, and then the other two coils are activated to generate a magnetic field, thereby driving the motor to rotate. Since four-phase stepper motors have four inputs, they can be divided into smaller step angles, which are more precise than two-phase stepper motors.
2.Control method
1.Two-phase stepper motors
Since two-phase stepper motors have only two control inputs, their drive circuits are relatively simple, and only one H-bridge drive circuit is needed to control their operation. Among them, the H-bridge drive circuit is a circuit used to control the direction and size of the current, which consists of four switches. The size and order of the control current can determine the direction and speed of the motor rotation.
2.Four-phase stepper motor
Since the four-phase stepper motor has four inputs, it requires a more complex control circuit. It can be driven by an external controller such as a stepper motor controller or a microcontroller. In addition, since the four-phase stepper motor can be divided into smaller step angles, the requirements for the drive circuit are higher than those for the two-phase stepper motor.
3.Output efficiency
There are also differences in output efficiency between two-phase stepper motors and four-phase stepper motors. Since the step angle of the two-phase stepper motor is relatively large and the rotation speed is relatively slow, it is suitable for low-speed and low-precision applications. The four-phase stepper motor has a finer step angle and a faster rotation speed, which is suitable for high-speed and high-precision applications.
4.Application field
Two-phase stepper motors are mainly used to control low-speed and low-precision applications. If high-speed and high-precision control is required, four-phase stepper motors are usually used. Common applications include: electronic scales, printers, scanners, etc.
5.Conclusion
Although two-phase stepper motors and four-phase stepper motors both belong to the category of stepper motors, they have some differences in working principle, control method, output efficiency, etc. Understanding these differences can help readers better choose the type of motor suitable for their application field.
Source:https://www.steppernews.com/2024/07/the-difference-between-two-phase.html