B5: Pid Control - YASKAWA GA800 Programming Manual

2.3 b: Application
■
b4-07: Terminal M5-M6 ON-Delay Time
No.
Name
(Hex.)
b4-07 Terminal M5-M6 ON-Delay
Time
(0B34)
Expert
■
b4-08: Terminal M5-M6 OFF-Delay Time
No.
Name
(Hex.)
b4-08 Terminal M5-M6 OFF-Delay
Time
(0B35)
Expert
◆

b5: PID Control

The drive has a PID control function. You can control drive output to adjust the proportional gain, integral time, and
derivative time that has an effect on the bias between the target value and the feedback value to align the target value
with the detected value. Use this function to adjust the drive output to accurately match the flow, pressure, and
temperature in the application match the target value.
Use a combination of these controls to increase the performance:
• P control
P control has a proportional effect on the deviation. It outputs the product (the controlled output) proportional to the
deviation. You cannot use only the offset from P control to get to zero deviation.
• I control
I control is the integral of the deviation. It uses an integral value of the deviation to output the product (the
controlled output). I control helps align the feedback value and the target value. If you use the proportional effect (P
Control) only, it will cause offset. If you use the proportional effect with the integral operation, it will gradually
remove the offset over time.
• D control
D control is the derivative of the deviation. If there are sudden, large changes in the deviation or feedback value, it
will have an effect on drive output. It quickly returns drive output to the value before the sudden change. It
multiplies a time constant by a derivative value of the deviation (slope of the deviation), and adds that result to PID
input to calculate the deviation of the signal, then it corrects the deviation.
Note:
D control has causes less stable operation because the noise changes the deviation signal. Use D control only when necessary.
■
PID Control Operation
Figure 2.34 shows PID control operation. The modified output (output frequency) changes when the drive uses PID
control to keep the deviation (the difference between the target value and the feedback value) constant.
222
V/f CL-V/f OLV CLV AOLV
Sets the delay time to activate the contact after the function set in H2-03 activates.
V/f CL-V/f OLV CLV AOLV
Sets the delay time to deactivate the contact after the function set in H2-03 deactivates.
Figure 2.34 PID Control Operation
Description
OLV/PM AOLV/PM CLV/PM EZOLV OLV/PM
Description
OLV/PM AOLV/PM CLV/PM EZOLV OLV/PM
YASKAWA TOEPYAIGA8002B GA800 Drive Programming
Default
(Range)
0 ms
(0 - 65000 ms)
Default
(Range)
0 ms
(0 - 65000 ms)