1. Definition of servo system:
Servo system definition: is to make the object's position, orientation, state, and other output controlled quantity, can follow the input quantity (given value) of any change and change of automatic control system, servo word comes from the Latin word Servus, which means to faithfully carry out the master's command.
A servo system generally consists of a servo motor and a servo drive. The servo drive provides the voltage and current required for the operation of the servo motor, which is generally connected to the load device to be driven when the motor is in use to provide the driving force for it. By adjusting the voltage (current) supplied to the motor, the driver can control the motor's output torque, output speed, and stop position. Servo motors, according to their structure, have brush servo motors, AC servo motors, direct-drive servo motors, linear servo motors, and so on.
2. Dervo system characteristics:
(1). High-precision positioning
Servo system is a closed-loop control system, servo drive according to the encoder feedback position adjustment control motor operation, at the same time because of the encoder, the servo system is equivalent to the same as the eyes, there will not be a stepping motor loss of step phenomenon, the other can be dynamically adjusted according to the state of the load motor's output torque, the motor's speed, the motor's rotational angle and so on to achieve the same with the instruction. Through the selection of high-precision encoder can achieve very high control and positioning accuracy. For example, the industry's commonly used optical encoder single-turn resolution of 23bit, after conversion unit positioning accuracy of 1/8388608, that is, the motor is a circle of 360 degrees divided into 8388608 parts.
(2). Flexible control mode
Most servo systems support six control modes: position control, speed control, torque control, position-speed control switching, position-torque control switching, and speed-torque control switching. According to the needs of the equipment, you can flexibly choose different control methods to realize different control effects.
(3). Wide coverage of product capacity
Servo system capacity covers a very wide range of common servo systems on the market from a few watts to dozens of kilowatts have related products to choose from, and a wide range of applications.
(4). Energy efficient, long life
Servo system due to its special closed-loop control, according to the size of the load dynamic control of the motor's output, motor heating is small, so its efficiency is significantly higher than ordinary motors, with a general conversion efficiency of up to 90% or more. Has been the enterprise equipment energy-saving transformation tool. At the same time, because the servo motor (AC) belongs to the brushless motor, the motor drive current phase switching in the drive using electronic components, and the traditional brush motor brushes are easy to wear compared to the servo system is maintenance-free, life expectancy is generally up to more than 10 years, and even decades of use can be found in the normal operation of the example.
3. The field of application
Servo system applications are very broad, covering machinery, metallurgy, electric power, petrochemical, shipbuilding, aerospace, construction, transportation, agriculture, scientific research and testing, and other fields. According to the equipment, the industry can also be divided into machine tools, printing equipment, medical equipment, semi-conductor manufacturing equipment, 3C product manufacturing equipment, injection molding equipment, food processing equipment, security equipment, packaging equipment, textile equipment, laser processing equipment, robots, automated production lines and so on.