How to choose and judge the quality of integrated stepper motors

1.Introduction

An integrated stepper motor refers to a design that integrates the driver and stepper motor of a stepper system into one. This design not only greatly saves installation space, but also simplifies the cumbersome wiring process and enhances the practicality of the stepper system. Integrated stepper motors usually inherit the excellent characteristics of control and drive in one, saving design costs and time costs for customers, and are suitable for customers to choose stepper system solutions

2.Methods for selecting suitable integrated stepper motors

1.Selection of step angle: The step angle depends on the requirements of load accuracy. Convert the minimum resolution of the load to the motor shaft, and the angle that each equivalent motor should walk. The step angle of the motor should be equal to or less than this angle. Common step angles on the market are 0.36 degrees/0.72 degrees, 0.9 degrees/1.8 degrees, 1.2 degrees, etc.

2.Selection of static torque: The basis for the selection of static torque is the load of the motor, including inertial load and friction load. The static torque should be 2-3 times the friction load. Once the static torque is selected, the motor base and length can be determined.

3.Current selection: Motors with the same static torque have very different operating characteristics due to different current parameters. The current of the motor can be determined based on the torque-frequency characteristic curve.

4.Speed ​​and accuracy: When the speed requirement is high, a motor with a larger phase current and a smaller inductance should be selected to increase the power input, and a higher supply voltage should be used when selecting the driver. Determine the requirements for positioning accuracy and vibration, and determine whether and how many subdivisions are required.

5.Special specifications and environmental adaptability: If a stepper motor with special specifications is required, such as the diameter, length, and extension direction of the output shaft, it is usually necessary to communicate with the manufacturer and customize it within the scope allowed by technology. For special environments, such as waterproof and corrosion-resistant stepper motors, they are suitable for certain special occasions. For example, underwater robots require waterproof motors. ‌

3.Methods for judging integrated motor failure

1.Check insulation resistance: Use an insulation resistance megohmmeter to measure the insulation resistance of the motor. If the insulation resistance is greater than 0.5 megohms, it means that the insulation performance of the motor is good. ‌

2.Test DC resistance: Use the resistance range of a multimeter to test the DC resistance of the three windings of the motor. If the DC resistance of the three windings is similar and the deviation is small, it means that there is no inter-turn short circuit in the winding. ‌

3.Manual rotation test: Without connecting any equipment or wires, manually rotate the motor shaft. If it rotates smoothly and there is no jamming, it means that the motor is normal. ‌If jamming or failure to rotate occurs, it may indicate that the motor is broken or there is an internal problem. ‌

4.No-load power-on test: Power on the motor and observe whether the three-phase current is balanced and whether the motor rotates smoothly. Pay attention to abnormal conditions such as temperature rise and abnormal noise of the motor. ‌

5.Check the stepper motor driver: If the red light of the stepper motor driver keeps flashing, it may be that the power supply voltage is unstable or there is a problem with the control signal. Use a multimeter or other instrument to check the power supply voltage and control signal, and also check whether the stepper motor itself has any faults.

Source:https://ameblo.jp/angla27/entry-12861479660.html

Introduction to the functions and troubleshooting of closed-loop stepper motor drivers

1.Overview

A closed-loop stepper motor driver is a motor driver that integrates multiple functions such as speed regulation, positioning, increasing output torque, and reducing mechanical noise. It is mainly used in equipment and occasions that require high-precision positioning, stability, and reliability. This article will start from the principle and function of the closed-loop stepper motor driver and introduce its characteristics and solutions to common faults in detail.

2.Characteristics of closed-loop stepper motor drivers

1.High precision: The closed-loop stepper motor driver can provide high-precision motion control and can achieve operation with small steps, with the minimum step reaching 0.001mm.

2.High speed: The maximum speed of the closed-loop stepper motor driver can generally reach 1000r/min, and its speed and torque output are related to the load and voltage of the motor.

3.Low noise: The output torque of the closed-loop stepper motor driver is stable, the operation is smooth, and the mechanical noise can be reduced.

4.Low vibration: The change of the output signal of the closed-loop stepper motor driver can make the control system respond more quickly, thereby reducing vibration and jitter and improving the control accuracy of the motor.

5.High reliability: The closed-loop stepper motor driver adopts a closed-loop control system, which can achieve precise position control and improve the reliability of the system.

3.Common faults and treatment methods

1.Emergency stop fault: When the controller stops suddenly, the motor driver will rotate too fast. The treatment method for this fault is to restart the controller for debugging and check whether the wiring of the motor driver is normal. If the wiring is confirmed to be correct and the fault still exists, the motor driver needs to be replaced.

2.Parameter setting error: When the parameters of the motor driver are set incorrectly, abnormal or unsmooth movement will occur. For this fault, the solution is to carefully check whether the equipment parameter settings are correct and make corresponding adjustments.

3.Excessive noise: When the motor is running and there is a fault of excessive noise, it is necessary to check whether the motor has foreign matter or wear and tear, and adjust and replace the parts with poor contact.

4.Unable to move: When the motor cannot move normally, it is necessary to check whether the power supply of the controller is stable, whether the control circuit is faulty, and to check and repair the problems one by one.

5.Failed to return to zero: When the motor cannot return to zero, it is necessary to check whether the connection between the motor and the sensor is normal, whether the parameter settings are correct, etc., and make corresponding adjustments.

4.Conclusion

The above is a detailed explanation of the function introduction and troubleshooting of the closed-loop stepper motor driver in this article. The closed-loop stepper motor driver has a wide range of applications, but it also has many fault phenomena. Therefore, the ability to repair and troubleshoot is also very important. Readers can have a deeper understanding of the driver through the study of this article and be able to better deal with faults.

The difference between two-phase stepper motors and four-phase stepper motors

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.

How to realize speed regulation of three-phase stepper motor

1.Overview of three-phase stepper motor

The three-phase stepper motor is an actuator that converts electrical pulse signals into angular displacement. It has the advantages of simple structure, convenient control, high precision, and no cumulative error. It is widely used in automation equipment such as CNC machine tools, robots, printers, scanners, etc.

2.Speed ​​regulation principle of three-phase stepper motor

Speed ​​regulation refers to changing the speed of the motor to meet different working requirements. The speed regulation of three-phase stepper motors is mainly achieved in the following two ways:

1.Pulse frequency speed regulation: By changing the pulse frequency input to the motor driver, the speed of the motor can be changed. The higher the pulse frequency, the faster the motor speed.

2.Current control speed regulation: By adjusting the current in the motor winding, the torque of the motor can be changed, thereby affecting the speed. The larger the current, the greater the torque and the faster the speed.

3.Speed ​​regulation method of three-phase stepper motor

1.Microstep control: By subdividing the step angle of the motor, more precise control can be achieved. For example, subdividing the step angle of 1.8 degrees into 0.9 degrees can improve control accuracy and smoothness.

2.PWM control: Use pulse width modulation (PWM) technology to adjust the current size in the motor winding to achieve smooth speed regulation.

3.Vector control: By controlling the direction and size of the motor's magnetic field, efficient and accurate speed regulation is achieved.

4.Current chopping control: By adjusting the on and off time of the current, the motor speed is controlled.

5.Hybrid control: Combine the above control methods to achieve better speed regulation performance.

4.Implementation steps of three-phase stepper motor speed regulation

1.Determine the speed regulation requirements: According to the application scenario, determine the required speed regulation range and accuracy.

2.Select a suitable driver: According to the motor parameters and speed regulation requirements, select a suitable stepper motor driver.

3.Design control circuit: Design a suitable control circuit to achieve control of the motor driver.

4.Write a control program: According to the control requirements, write a control program to achieve precise control of the motor.

5.Debug and optimize: Through actual operation, debug and optimize the control parameters to achieve the best speed regulation effect.

Three-phase stepper motor speed regulation technology has a wide range of applications and prospects in the field of automation. By choosing the appropriate speed regulation method and control strategy, the motor can be precisely controlled to meet the needs of different scenarios. With the continuous advancement of control technology, the speed regulation performance of three-phase stepper motors will be further improved, providing a stronger driving force for the development of automation equipment.