Pid Gain Adjustment - Mitsubishi Electric A800 Plus Series Function Manual

Parameter setting procedure for tension sensor feedback speed control
4.4.2

PID gain adjustment

Adjust the PID gain for tension sensor feedback speed control.
Adjustment by tension PI gain tuning (recommended)
The PID gain is adjusted by tension PI gain tuning (refer to
adjustment.
Manual adjustment
• Set the minimum-diameter roll for winding and the maximum-diameter roll for unwinding. Connect the material from the
beginning to the end of the machine, and increase the line speed gradually while observing the tension feedback value.
Adjust the line speed so that appropriate tension feedback value can be obtained.
• Adjust the PID gain so that the dancer roll works without problems at acceleration, constant speed, deceleration, and
sudden deceleration.
• It is important to adjust the tension PI gain as high as possible for the minimum-diameter roll.
• Normally, adjust the gain with Pr.129 PID proportional band and Pr.130 PID integral time.
Slow response
(the tension feedback position is too low)
POINT POINT
• Adjust the gain so that overshooting occurs once or so before the tension feedback value returns to the set point.
• Refer to the following according to the tension feedback condition.
Status
When the response is
slow (the tension
feedback value is too low)
When the response is
fast (hunting occurs too
frequently)
NOTE
• Set Pr.134 PID differential time only when it is necessary as it causes hunting. However, set a small value in Pr.134 PID
differential time to cease fluctuation of the tension feedback value by disturbance and such at an early point. (Set 0.01 s at
first and gradually increase the value.)
104
TENSION SENSOR FEEDBACK SPEED CONTROL
• Decrease Pr.129 PID proportional band by 10%.
• Decrease Pr.130 PID integral time by 0.1 s.
• Repeat the adjustment procedure in the range from the minimum diameter to the maximum diameter so that
the dancer roll moves properly at acceleration, constant speed, deceleration, and sudden deceleration.
• Increase Pr.129 PID proportional band by 10%.
• Increase Pr.130 PID integral time by 0.1 s.
• Repeat the adjustment procedure in the range from the minimum diameter to the maximum diameter so that
the dancer roll moves properly at acceleration, constant speed, deceleration, and sudden deceleration.
page 76). Tension PI gain tuning is recommended for PID gain
Proper condition
Adjustment method
Fast response
(hunting occurs too frequently)