11. What is the principle of parameter adjustment of speed loop and position loop of servo drive?
In addition to the performance of the motor and the drive, the adjustment of the drive parameters is also a very critical factor.
There are three main performance parameters of the servo drive: speed loop proportional gain, velocity loop integration time constant, and position loop proportional gain. The corresponding parameter numbers of the EDB servo drive are: velocity loop proportional gain (PN013), velocity loop integration time constant (PN014) and position loop proportional gain (PN015).
The velocity loop proportional gain, the integration time constant only works on the motor when it is running (with velocity). The size of the proportional gain of the speed loop affects the response speed of the motor, and the size of the integration time constant of the speed loop affects the steady-state speed error of the motor and the stability of the speed loop system. EDB series servo drives are shipped with a default value and a corresponding speed loop bandwidth. The default value is set for light load. When the servo motor carries the actual load, because the actual load torque and load inertia are not consistent with the default value setting, the bandwidth of the speed loop will be narrowed, if the speed loop bandwidth at this time meets the demand, there is no phenomenon such as motor speed creep or oscillation, the proportional gain and integration time constant of the speed loop can not be adjusted. If the actual load makes the motor work unstable, creeping or oscillating phenomena occur, or the existing speed loop bandwidth is not ideal, the proportional gain and integration time constant of the speed loop need to be adjusted.
The principle of speed loop parameter adjustment is to ensure the stability (no oscillation) of the speed loop system, and allow overshoot and only one wave head with a small amount of overshoot, so that the speed loop responds the fastest and the system works stably.
In order to ensure the stable operation of the system, the speed loop integration time constant should be adjusted. The principle of adjustment is that the greater the multiple of the actual total inertia of the motor and the rotor inertia of the motor converted from the load inertia to the motor shaft, the greater the value of the velocity loop integration time constant should increase.
The reciprocal of the integral time constant of the velocity loop is the integral gain. An increase in the velocity loop integration time constant will lead to a slower response of the velocity loop. Increasing the proportional gain of the speed loop can achieve a faster response speed under the premise of ensuring the stability of the system.
To increase the integration time constant of the velocity loop, it is necessary to increase the proportional gain of the velocity loop accordingly to improve the response time of the velocity loop. The adjustment of these two parameters is an iterative process, which requires accurate understanding and experience of the load.
The upper limit of the increase in the proportional gain of the velocity loop is below the critical oscillation point of the system. The simple way to do this is to increase the proportional gain of the velocity loop until the system oscillates, and then decrease the proportional gain of the velocity loop by a little bit, which is the proportional gain of the stiffer velocity loop.
In summary, under the premise that the system can work stably, a larger proportional gain of the velocity loop and a smaller velocity loop time constant can obtain a better velocity response. The proportional gain of the velocity loop is large and the time constant of the velocity loop is too small, and the system oscillates in the larger capacity, and the operation is unstable. The small proportional gain of the speed loop and the excessive speed loop time constant, the speed response of the motor is low, and the motor is prone to creeping when running.
The position ring proportional gain is only valid when the driver is operating in position mode. When the servo motor stops running, increase the proportional gain of the position ring, which can improve the locking rigidity of the servo motor. When the servo motor is running under the position ring, the position lag will change when the proportional gain of the position loop is increased and decreased.
The principle of proportional gain adjustment of the position loop is to increase the proportional gain of the position loop to reduce the position lag under the premise of ensuring the stable operation of the position loop system and the position is not out of tolerance (overshoot). The simple way is to increase the proportional gain of the position loop until the system is out of tolerance (overshoot), and then decrease the proportional gain of the position loop by a little, which is the proportional gain of the position loop with better stiffness.
When the proportional gain and integration time constant of the velocity loop are used by default, the proportional gain of the position loop can be adjusted to reduce the position lag and improve the position following characteristics. It is recommended to adjust the proportional gain of the position ring.
When multiple axes are interpolated at the same time, the proportional gain value of each axis should be adjusted to the same.
|
More on that
|
Estun servo motor - from which aspects to check the servo motor overheating
(1) The motor heat dissipation system is faulty
The temperature of the motor rises due to the heat generated by the motor not being dissipated quickly. At this time, the main solution is to check whether the cooling fan of the motor is operating normally and whether the direction of rotation of the fan is correct. The surface of the motor is ...
|
|
Estun Servo Motor - Introduction to Servo Motor Inertia Knowledge
1. What is "inertia matching"?
1. According to Newton's second law: "The required moment T of the feed system = the transmission inertia of the system J×angular acceleration θ angle". The acceleration θ affects the dynamic characteristics of the system, the smaller θ, the more time from the controller to the completion of the system's execution.
|
|
Estun servo motor - the basic application of AC servo motor
Material metering
The measurement of powdery materials is commonly used in the way of screw measurement. The purpose of measurement is achieved by the number of turns of the screw rotation. In order to improve the accuracy of measurement, the speed of the screw is required to be adjustable, and the position positioning is accurate.
|
|
Estun Servo Motor – The stepper motor controller is different from the servo motor controller
First, the working principle is different
Stepper motor controller: It is an electronic product that can send out a uniform pulse signal, and the signal it sends out enters the stepper motor driver, which will be converted by the driver into a strong current signal required by the stepper motor to drive the stepper motor to run. Stepping ...
|
|
Estun Servo Motor – Several parameter settings for servo motor drives
1. Position proportional gain
Set the proportional gain of the position ring adjuster; The higher the set value, the higher the gain, the greater the stiffness, and the smaller the position lag under the same frequency command pulse. However, too large a value may cause oscillation or overshoot; The parameter values are determined by the specific servo system type ...
|
|
Estun Automation won the 2019 Golden Globe Award for High-tech Robots
On December 11, the 2019 Golden Globe Award Annual Conference of the Industrial Robot Industry Event "Ecological Interconnection • Breaking Through Against the Trend" was held in Shenzhen.
Zhu Chunhua of Estun Automation was invited to publish "How China's Intelligent Manufacturing Enters the Global ...
|
|
Estun servo motor - maintenance and maintenance of DC motor
Special attention should be paid to the following matters when the motor is regularly inspected during use:
1. The area around the motor should be kept dry, and no other objects should be placed inside and outside it
The cleaning of the motor shall not be less than once a month, and the dust inside shall be blown off with compressed air during cleaning.
|
|
Estun servo motor - six common faults and solutions for servo motors
1. The motor temperature is too high or the smoke is faulty
Cause:
1. Excessive load
2. Two-phase operation
3. Air duct obstruction
4. The ambient temperature increases
5. Stator windings are short-circuited between phases or turns
6. Stator winding grounding
7. The power supply voltage is too high ...
|
|
Estun Servo Motors – Encoder FAQs
1. Q: What are the precautions for the selection of incremental rotary encoders?
There are three parameters that should be noted:
1. Mechanical installation dimensions, including positioning stops, shaft diameters, and mounting holes; cable outlet mode; installation space volume; Whether the protection level of the working environment meets the requirements.
...
|
|
Estun servo motor - classification and introduction of common servo control systems
The servo control system is an operating system that can automatically control the mechanical movement of the test device according to the predetermined requirements. There are many classification methods for servo systems, and there are three common classification methods:
1. Classification according to the characteristics of the controlled parameters.
2. According to the type of drive element ...
|
|
Estun servo motor - what are the control methods of servo motor?
1. Torque control: The torque control mode is to set the size of the output torque of the motor shaft through the input of the external analog quantity or the assignment of the direct address, which is specifically manifested as if 10V corresponds to 5Nm, when the external analog quantity is set to 5V, the output of the motor shaft is 2.5Nm: if the motor shaft ...
|
|
Application characteristics of Estun palletizing robots
1. The palletizing robot is mostly four-axis, flexible in operation, and the load can reach 180 kg.
2. It can carry out high-precision handling and palletizing work, save a lot of labor for enterprises, and promote modern production.
3. Customized according to the on-site needs of the enterprise, high work efficiency, 24 hours uninterrupted...
|
|
Estun servo drive alarm A20 common fault analysis
1. Estun servo motor maintenance - overload alarm A04
1. The wiring of the servo motor is wrong or the wiring is leaking
(1) The U, V, and W phase wires of the motor are connected incorrectly
(2) Whether the insertion of the connector on the servo motor side is defective
2. The model of the servo drive and the motor does not match
...
|
|
Estun servo motor - what are the control methods of servo control system?
Generally, there are three control modes for servo: speed control mode, torque control mode, and position control mode.
1. Speed control
(1) Speed system, that is, the motor runs according to the given speed command.
(2) The application of speed control is quite wide-ranging ...
|
|
Estun servo motor – three modes of servo control
The speed control and torque control of the servo motor are controlled by analog quantity, and the position control is controlled by generating pulses. The specific control method to use should be selected according to the customer's requirements and what kind of motion function is satisfied.
Generally, there are three control modes for servo: speed control ...
|
|
Estun Servo Motor – How to maintain and care for servo motors
1. Regularly check the encoder connection line of the servo motor and the power connector of the servo motor to confirm that they are firmly connected;
2. If the servo motor is connected to a reduction gear, the servo motor should be sealed with oil to prevent the oil from the reduction gear from entering the servo motor.
...
|
|
Estun servo motor - common faults and treatment methods of servo motors
1. Motor encoder alarm
1. The cause of the failure
(1) Wiring fault;
(2) electromagnetic interference;
(3) Encoder hardware damage caused by mechanical vibration;
(4) Pollution caused by the on-site environment.
2. Fault cleaning
(1) Check the wiring and sweep away the fault ...
|
|
A detailed introduction to Estun's servo control mode
From the perspective of the protection response speed of the robot servo drive, Estun has a small amount of calculation in the form of torque, and the response to the control signal of the drive is fast. The azimuth form has a large amount of computation, and the response to the driver's control signal is slow.
1. If there is a relatively high demand for dynamic functions in sports...
|
|
What are the welding methods of Estun welding robots?
1. Applicable welding methods and cutting methods:
Generally, arc welding robots are only suitable for MIG/MAG welding, and there is no interference of high-frequency arc striking on the control and drive system of the robot. Whether it can be used for tungsten argon arc welding depends on whether the robot has a special anti-interference method.
|
|
Estun servo – the difference between servo motor and stepper motor
First, the control accuracy is different
The step angle of the two-phase hybrid stepper motor is generally 3.6 ° and 1.8 °, and the step angle of the five-phase hybrid stepper motor is generally 0.72 ° and 0.36 °. There are also some high-performance stepper motors with smaller step angles. Such as Sitong company produced a kind of wire for slow wire ...
|
|
Contact
working hours
