As an important power device, servo motor plays a key role in many fields. So, how can we choose a suitable servo motor? This requires us to have a detailed understanding of its performance parameters.
1. Main performance parameters of servo motor
(1) Rated power:
This refers to the power that the motor can continuously output. The rated power determines the ability of the servo motor to work for a long time. When selecting, the appropriate rated power should be determined based on the actual load requirements. If the power is too large, it will cause a waste of resources; if the power is too small, it cannot meet the working requirements, and the motor may be overwhelmed.
(2) Maximum torque
It reflects the maximum power that the motor can output. In some scenarios that require greater power, such as large equipment drives in industrial machinery, a larger maximum torque is required to ensure the normal operation of the equipment. If the torque is insufficient, the equipment may not start or run smoothly.
(3) Speed range
That is, the maximum and minimum speeds that the motor can reach. Different application scenarios have different requirements for speed. For example, in high-speed processing industrial machinery, a higher speed is required to improve production efficiency; while on some occasions that require precise position control, such as microscope focus adjustment on medical equipment, a lower speed may be required to ensure accuracy.
(4) Resolution
Refers to the smallest unit of motion that a motor can achieve. The higher the resolution, the higher the control accuracy of the motor. In some fields that require extremely high precision, such as semiconductor manufacturing, it is necessary to select servo motors with high resolution to ensure product quality and performance.
(5) Control method
The control methods of servo motors mainly include position control, speed control and torque control. Position control is suitable for occasions that require precise position positioning, such as robot joint control; speed control is used for equipment that requires constant speed operation, such as material transportation on a conveyor belt; torque control can automatically adjust the output torque of the motor according to the change of load to ensure stable operation of the equipment.
2. Application of servo motors in different scenarios
(1) Industrial automation
In this field, servo motors are widely used. For example, in CNC machine tools, they can accurately control the position and movement trajectory of the tool, thereby processing high-precision parts; in wind turbines, servo motors can adjust the angle of the blades according to the change of wind speed to achieve the best power generation efficiency; in printing machinery, servo motors can ensure the accurate transmission of paper and the accuracy of the printing position, thereby improving the printing quality.
(2) Aerospace field
The aircraft steering system is one of the important applications of servo motors. The steering system controls the aircraft’s control surfaces through servo motors to achieve aircraft attitude control and flight stability. The servo motor’s rapid response and precise control capabilities enable the aircraft to perform various complex flight maneuvers in the air, ensuring flight safety.
(3) Medical equipment field
Medical equipment has extremely high requirements for precision and reliability, and servo motors just meet this demand. In surgical robots, servo motors can accurately control the movement of surgical instruments, providing doctors with more precise operations; in imaging equipment, such as CT and MRI, servo motors are used to control the movement and positioning of the scanning bed to ensure the accuracy and clarity of the image.
(4) Elevator and automatic door field
Servo motors are widely used in the drive systems of elevators and automatic doors. They can achieve fast, safe and smooth motion control, improving the operating efficiency and comfort of elevators and automatic doors. At the same time, servo motors also have the advantages of energy saving and emission reduction, which meets the environmental protection requirements of modern society.
3. Factors to consider when selecting a servo motor
(1) Load requirements
First, the type and weight of the load to be driven must be clearly defined. Different loads have different requirements for motors, such as constant loads, variable loads, high-speed motion loads, etc., and a servo motor that matches them needs to be selected. If the load is large, a motor with large power and torque needs to be selected; if the load changes frequently, the dynamic response performance of the motor needs to be considered.
(2) Control accuracy requirements
For some applications that require high-precision control, such as medical equipment and semiconductor manufacturing, a servo motor with a high-resolution encoder and high-precision position control must be selected. For some occasions with relatively low accuracy requirements, a motor with general control accuracy can be selected, but it must also be ensured that it can meet the actual work requirements.
(3) Working environment conditions
Different working environments have a certain impact on the performance of servo motors. In high temperature, low temperature, humid or corrosive environments, it is necessary to select a motor that can adapt to these conditions and consider its protection level. For example, in a food processing workshop, a waterproof and moisture-proof servo motor needs to be selected; in a chemical production workshop, a corrosion-resistant motor needs to be selected.
(4) Maintenance and servicing costs
In some industrial production lines that require long-term continuous operation, the maintenance and servicing costs of servo motors are also factors that need to be considered. Choosing motors that are easy to maintain, and service can reduce the failure rate and operating costs of the equipment and improve the reliability of the equipment. For example, some motors have self-diagnosis functions that can detect faults and alarm in time, making it easier for maintenance personnel to perform maintenance.
4. Frequently Asked Questions and Answers about Servo Motors
Q1: What is the difference between a servo motor and a regular motor?
A1: A servo motor has high-precision control performance and can accurately control position, speed, and acceleration, while a regular motor is mainly used to provide power and has relatively low control accuracy.
Q2: How to determine the rated power of a servo motor?
A2: It needs to be determined based on the actual load size and working requirements. You can choose the appropriate rated power by calculating the torque and speed of the load and then using the motor power calculation formula.
Q3: Is the higher the resolution of the servo motor, the better?
A3: In situations where high precision is required, a high-resolution servo motor is necessary. However, in some applications where precision is not required, too high a resolution may increase costs, so it is necessary to choose according to actual needs.
Q4: Can the control mode of the servo motor be switched?
A4: Some servo motor control systems support switching between multiple control modes, but not all motors have this function. When choosing, you need to determine whether a switchable control mode is required based on the specific application scenario and control requirements.
Q5: Will the servo motor generate heat during operation?
A5: The servo motor will generate a certain amount of heat during operation. Therefore, the heat dissipation conditions of the motor need to be considered during installation to ensure that the motor can operate within the normal temperature range.
Q6: How to improve the response speed of the servo motor?
A6: The response speed of the motor can be improved by adjusting the motor’s control parameters, such as the speed loop proportional gain, position loop proportional gain, etc. However, when adjusting, care should be taken to avoid motor vibration or instability.
Q7: How long is the service life of a servo motor?
A7: The service life of a servo motor is related to many factors, such as the working environment, load conditions, maintenance, etc. Under normal use and maintenance, the service life of a servo motor can reach several years or even longer.
Q8: Can servo motors work underwater?
A8: There are special waterproof servo motors that can work underwater, but ordinary servo motors do not have waterproof functions. If you need to use it underwater, you need to choose a motor that meets the waterproof requirements and take corresponding waterproof measures.
Q9: Is the servo motor noisy?
A9: Under normal circumstances, the noise of the servo motor is relatively small. However, if the motor fails or is installed improperly, it may cause increased noise. Therefore, during use, it is necessary to pay attention to the operating status of the motor and find and solve problems in time.
Q10: Is the price of servo motor expensive?
A10: The price of servo motor varies depending on factors such as brand, model, and performance. The price of high-performance servo motors is relatively high, while the price of ordinary performance motors is relatively low. When choosing, you need to consider it comprehensively based on actual needs and budget.
