Danfoss VLT Series Design Manual page 37

®
VLT HVAC Drive Design Guide
Type of Control
PI-control
PID tight control
PID some overshoot
Ziegler Nichols tuning for regulator, based on a stability boundary.
Experience has shown that the control setting according to Ziegler Nichols rule provides a good
closed loop response for many systems. If necessary, the operator can do the final tuning of the
control iteratively to modify the response of the control loop.
Proportional Gain
K
0.45 *
u
K
0.6 *
u
K
0.33 *
u
®
MG.11.B2.02 - VLT is a registered Danfoss trademark
2. Introduction to VLT HVAC Drive
Integral Time Differentiation
Time
P
0.833 * -
u
P
0.5 * 0.125 *
u
P
0.5 * 0.33 *
u
P
u
P
u
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