Speed, corresponding to these two ways, MD330 has designed two tension control modes.
Open loop means that there is no tension feedback signal, and the inverter can be controlled only by controlling the output frequency or torque.
The control purpose has nothing to do with open-loop vector or closed-loop vector. Torque control mode means that the inverter controls the motor.
It is torque rather than frequency, and the output frequency changes automatically with the speed of the material.
According to the formula F=T/R (where f is the material tension, t is the torque of the winding shaft, and r is the winding radius),
It can be seen that if the torque of the winding shaft can be adjusted according to the change of winding diameter, the tension on the material can be controlled.
This is the basis of tension control by open-loop torque method, and its feasibility is also due to the tension on the material.
The torque only comes from the winding shaft, which mainly acts on the material.
MD series inverter can accurately control power under closed-loop vector control (vector control with speed sensor).
The machine outputs torque. To use this control mode, an encoder must be installed (the frequency converter should be equipped with PG card). 1) tension setting part: used to set tension. In actual use, the set value of tension should be consistent with the materials used.
The requirements of crimping correspond to the actual situation and need to be set by the user. Tension taper can control tension.
It decreases with the increase of winding diameter, which is used to improve the effect of winding forming.
2) Coil diameter calculation part: used to calculate or obtain coil diameter information, which is needed if the coil diameter is calculated at linear speed.
For the linear speed input function, if the winding diameter is calculated by thickness accumulation, the winding diameter phase is calculated by thickness accumulation.
Close the parameter function section.
3) Torque compensation part: part of the output torque of the motor is used to overcome the charging (discharging) during acceleration and deceleration.
The inertia moment of the winding roller and the inertia compensation part of the frequency converter can be automatically set by appropriate parameters.
Torque compensation is carried out according to the acceleration and deceleration rate, so that the system can still obtain stable tension during acceleration and deceleration. difficulty
Friction compensation can overcome the influence of system resistance on tension. Closed-loop refers to the closed-loop adjustment that requires the feedback signal of tension (position) detection. The speed control mode is
Refers to the frequency converter to adjust the output frequency according to the feedback signal, and achieve the purpose of control, frequency converter can work in speed mode.
It is used for vector control without speed sensor, vector control with speed sensor and V/F control.
Any kind.
The principle of this control mode is to calculate a matching frequency setting value through the linear speed of the material and the actual winding diameter.
F 1, and then generate a frequency adjustment value f2 through the PID operation of the tension (position) feedback signal, and finally.
The frequency output is f=f 1+f2. F 1 can basically make the linear speed of winding (unwinding) and material basically the same.
Matching, and then the f2 part can meet the control requirements with a little adjustment, which solves the problem of closed-loop control well.
The contradiction between response speed and control stability.
In this mode, the tension setting part is invalid, and the purpose of system control is set in the given source of FA-00PID.
The result of control is to stabilize the tension (position) feedback signal at a given PID value. special
When using position signals (such as tension rocker and floating roller) as feedback, pay attention to changing the set value (PID given).
It may not be able to change the actual tension, and changing the tension requires changing the mechanical configuration.
Counterweight of swing rod or floating roller. 1)PID part: it is mainly set in FA group, and the second group of PID parameters in FH group can play an auxiliary role.
Use. After all other parts are set correctly, the final control effect needs to adjust PID parameters.
2) Linear speed input part: This part is more important and has two functions. One is to calculate the linear velocity.
The matching frequency of the inverter (see the above description), and the second is that the wire speed can calculate the winding diameter.
3) coil diameter calculation part: calculate the actual coil diameter, which can be obtained after the inverter obtains the linear speed and the actual coil diameter.
Take the matching frequency of the frequency converter. When calculating the coil diameter with linear velocity, if the coil diameter calculated by frequency converter is different from the actual coil.
Diameter deviation refers to the deviation of linear velocity input, which can be corrected by the calculation result of winding diameter.
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Note that the matching frequency value calculated by linear speed and winding diameter is not the actual output frequency of the inverter.
When calculating the winding diameter with linear speed and operating frequency, the operating frequency used is the actual output frequency of the inverter.
There is no contradiction in logic.
4) the second group of PID parameters: when only one group of PID parameters can not meet the overall control effect,
You can use the second set of PID parameters, for example, adjust the first set of PID parameters during low volume to get better results.
When the volume is full, adjust the second group of PID parameters to get better results, so that the whole process can achieve better results.