Classification and technical characteristics of servo motors

1.Definition of servo motors

A servo motor is an engine that controls the operation of mechanical components in a servo system. It is an auxiliary motor indirect speed change device. The servo motor can control the speed and position accuracy very accurately, and can convert the voltage signal into torque and speed to drive the control object. The rotor speed of the servo motor is controlled by the input signal and can respond quickly. In the automatic control system, it is used as an actuator, and has the characteristics of small electromechanical time constant, high linearity, and starting voltage. It can convert the received electrical signal into angular displacement or angular velocity output on the motor shaft.

2.Classification of servo motors

1.DC servo motor

The DC servo motor is the earliest servo motor. It is powered by a DC power supply and can achieve precise control of the motor by controlling the current size and direction. It has high speed and torque, fast response speed, and high control accuracy. It is suitable for industrial automation fields with high-precision control, such as CNC machine tools, printing machines, packaging machines, etc. However, due to the presence of brushes and brush rings in DC servo motors, long-term operation may cause brush wear, affecting the performance and life of the motor.

2.AC servo motor

The AC servo motor is powered by an AC power supply and has a high speed and torque. It uses the principle of electromagnetic induction to convert electrical energy into mechanical energy and achieves precise control through pulse signals. The AC servo motor has a simple structure, brushless commutation, and long life. It is suitable for fields with high-precision control and high-power output, such as wind turbines, ship power systems, rail transportation, etc. In addition, the AC servo motor also has good dynamic performance and anti-interference ability, which can meet the working requirements in various complex environments.

3.Brushless servo motor

The brushless servo motor is a motor without brushes and brush rings, and the current and torque are controlled by an electronic controller. It has the characteristics of high efficiency, high reliability and long life, and is suitable for application scenarios that require high precision and long-term operation. Brushless servo motors are widely used in robots, automation equipment, medical equipment and other fields.

3.Technical characteristics of servo motors

1.High precision

The servo motor adopts advanced closed-loop control technology, and the encoder provides real-time feedback of the motor's position and speed information to achieve precise control. Its positioning accuracy can reach 0.001mm, or even higher, and is suitable for occasions with extremely high position accuracy requirements.

2.High response speed

Servo motors have fast response capabilities and can reach the target position and speed in a very short time. This makes it have significant advantages in situations where high-speed and high-precision motion is required.

3.Good stability

Servo motors use advanced control algorithms and drive technologies to maintain stable operating performance in various complex environments. At the same time, they have strong anti-interference capabilities and can effectively resist external interference and noise.

4.High flexibility

Servo motors can be customized according to actual needs to meet the needs of different applications. In addition, it supports multiple control modes, such as position control, speed control, and torque control.

5.Other technical features

Servo motors also have the characteristics of high efficiency, low noise, and low heat generation. Its high efficiency is reflected in the ability to convert more electrical energy into mechanical energy and reduce energy waste; low noise and low heat generation make it quieter and more comfortable during operation.

4.Methods for increasing the speed of servo motors

1.Adjust the feedback signal

The speed control of servo motors can be achieved through feedback signals, such as position feedback, encoders, etc. When the servo motor speed is low, the parameters of the feedback mechanism can be adjusted appropriately, such as increasing the resolution of the encoder or increasing the number of encoder lines, so as to improve the feedback accuracy of the servo motor and thus increase the speed.

2.Increase the voltage

Increasing the voltage is one of the important ways to increase the speed of the servo motor. The higher the voltage, the corresponding current will also increase, which will cause the motor to output greater torque, thereby increasing the speed. However, while increasing the voltage, it is necessary to pay attention to controlling the temperature of the motor to avoid damage caused by overheating.

3.Optimize the control parameters

Optimizing the control parameters of the servo motor can also increase the speed. When optimizing the control parameters, it is necessary to consider factors such as the parameters of the feedback link, the parameters of the feedforward link, and the response speed of the controller, and conduct system analysis and simulation verification to finally obtain reasonable control parameters.

4.Replace the high-speed motor

If a higher speed is required, it can be achieved by directly replacing the high-speed servo motor. The high-speed servo motor is more sophisticated in design and can withstand higher speeds and loads, thereby achieving higher control accuracy and speed requirements.

5.Increase the mechanical reduction ratio

When the speed of the high-speed servo motor has reached the upper limit, a higher speed can be achieved by increasing the mechanical reduction ratio. The mechanical reduction ratio can be achieved by using mechanical elements such as gears, belts and couplings of different specifications. However, it should be noted that increasing the mechanical reduction ratio will reduce the output torque of the motor.