Pid Control Gain Setting - Mitsubishi Electric A800 Plus Series Function Manual

Dancer feedback speed control details
3.5.11

PID control gain setting

Set the proportional band, integral time, and differential time for PID control.
Pr. Name
129
R110 PID proportional band
(A613)
130
R111 PID integral time
(A614)
134
R112 PID differential time
(A615)
Block diagram
Tension PI gain
tuning not performed
PID control
gain selection
Tension PI gain
tuning result
Tension PI gain
tuning performed
Gain G switching
Pr.486 to Pr.494
Gain G switching
Deviation
Pr.486 to Pr.494
Tds
PID control proportional band (Pr.129)
• If a narrow proportional band is set (small parameter setting value), the manipulated amount changes considerably by
slight changes in the dancer signal.
PID control formula:
PID control integral time (Pr.130)
• Ti is the time required for integral (I) action alone to provide the same manipulated amount as is the case with proportional
(P) action.
• The set point is reached earlier when the integral time setting is shorter.
PID control differential time (Pr.134)
• Set the differential time for differential (D) action. Td is the time required to provide the same manipulated amount as is the
case with proportional (P) action. Response to changes in deviation increase greatly as the differential time increases.
84
DANCER FEEDBACK SPEED CONTROL
Initial value
100%
1 s
9999
Kp
Clamping
1
Kp
Tis
Pr.135, Pr.136
Gain G switching
tuning not performed
Kp
Pr.486 to Pr.494
0
Tension PI gain tuning performed
1
G Kp (1 +
·
Ti
·
Gain Kp = 1/proportional band
Ti = Integral time
Td = Differential time
Gain G = PID gain selection function: Refer to
Setting
range
If a narrow proportional band is set (small parameter setting value),
the manipulated amount changes considerably by slight changes in
0.1 to 1000% the measured value. As a result, response improves as the
proportional band becomes narrower, though stability worsens as
shown by the occurrence of hunting. Gain Kp=1/proportional band
9999 Without proportional band
With deviation step input, this is the time (Ti) used for obtaining the
same manipulated amount as proportional band (P) by only integral
0.1 to 3600 s
(I) action. Arrival to the set point becomes quicker the shorter an
integral time is set, though hunting is more likely to occur.
9999 Without integral control
With deviation ramp input, this is the time (Td) used for obtaining the
manipulated amount only by proportional action (P). Response to
0.01 to 10 s
changes in deviation increase greatly as the differential time
increases.
9999 Without differential control
Integral action
selection
X100-OFF
∫
Pr.485
Tension PI gain
0
X100-ON
+ Td S)
·
S
Description
Clamping
+
X103-OFF
100%
-100%
+ +
Held
X103-ON
page 89.
Manipulated amount