Servo control system encoder

(1) Servo system: It is an automatic control system that makes the output of the motion actuator, such as the position, direction, state, torque, etc. of the object, change with any change in the input ( given value).

(2) In the automatic control system, the system that can make a certain precision response to the control signal is called the follow-up system, also called the servo system. In order to ensure the accuracy of this immediate response, it is usually necessary to feedback  compare the position, speed  torque of the sensor, which is also called closed-loop control.

The main task of the servo system is to amplify, transform  adjust the power according to the requirements of the control command, so that the closed-loop control of the torque, speed  position output by the drive device is very flexible  convenient.

Simply put, it is the "obedience" of the position, time,  force of the motion system at any time,   how much force is output at this position, this is servo control.

Among them, if the motion system is driven by a motor, the corresponding relationship between the position of the motor  the operating current input by the motor is a problem that the servo control system must solve.  is the input voltage  current (including phase) of the motor? This is called position loop  current loop control. The change of position in time is the speed loop,  the change of the speed loop is acceleration  impulse.  physics we know that acceleration corresponds to force (such as gravitational acceleration G), the output force of the motor is driven by the input voltage  current (including phase),  then input  the motor, current loop = force,  the sensor fed back  the motor is acceleration = force. Through the feedback of the sensor to the motor, the position  acceleration information is obtained  compared with the control input to form a closed-loop servo control system.

A rotary encoder is a rotary position sensor that outputs incremental pulse signals (representing position changes)  absolute angle position signals. The first derivative of this signal with respect to time is velocity,  the second derivative is acceleration. Therefore, the rotary encoder becomes the feedback sensor of the servo system of choice.

servo motor:

The motor is a commonly used motion actuator. The motor driver directly performs closed-loop control on position, speed,  torque, which is called a servo motor. The commonly used servo motor is an AC permanent magnet synchronous motor,  sometimes an AC permanent magnet synchronous motor is directly called a servo motor.

AC permanent magnet synchronous motor:

The reason is that the rotor is made of permanent magnet materials, so after rotation, as the rotating magnetic field of the motor stator changes, the rotor will also change its speed with the change of frequency,  the speed of the rotor = the speed of the stator magnetic force, so it is called This is "synchronization." AC permanent magnet synchronous motors are equipped with encoders due to their synchronization requirements. The encoder  only provides angular position signal (such as incremental pulse signal  absolute digital signal), but also provides rotor position change phase signal (such as UVW  single-turn sine-cosine C, D signal), angular position signal as a closed loop of position  speed Feedback, using the rotor commutation signal to perform closed-loop feedback on the torque  thrust input of the motor current loop to obtain the synchronous rotation of the rotor. Therefore, the AC permanent magnet synchronous motor obtains position, speed, torque feedback information  closed-loop control due to the direct installation of the encoder,  naturally has "servo" characteristics.

In fact, AC permanent magnet synchronous motors can  only have servo characteristics, but also can realize position, speed  even output torque through controller (frequency converter)  sensor feedback (such as encoder). Through closed-loop control  tracking response, the characteristics of the servo system can also be realized.

Whether it can be called "servo" depends on whether its tracking response  control accuracy in terms of position, speed, output force, etc. can meet the requirements of use,  does  depend on what motor actuator is used.

Under the premise of the development of frequency conversion technology, the servo drive controller performs calculations on the internal current loop, speed loop,  position loop of the drive than general frequency conversion control technology  algorithm calculations,  is more powerful than traditional frequency converters in function. Many, mainly for precise position control. The speed  position are controlled by the host computer.

DEUPREE (Qingdao) Industrial Technology Co., Ltd. is an integrated enterprise focusing on the research  development of automated industrial technology  equipment manufacturing. The company’s products mainly include rotational motion sensors, linear displacement sensors, object recognition sensors, laser rangefinders, process Control  measurement instruments, signal detection systems, signal transmission systems, immature drive systems, UPS safety power supply systems,  automation equipment energy-saving  cleaning auxiliary equipment systems are  limited to this. We can also customize  flexibly customize according to customer needs. Meet the different needs of different customers.