Siemens Sinamics G120P Operating Instructions Manual page 359

Control optimization required
In some cases, the self optimization result is not satisfactory, or the inverter cancels the self-
optimization routine with a fault. Further, self optimization is not permissible in plants and
systems in which the motor cannot freely rotate.
In these cases you must manually optimize the closed-loop speed controller.
The examples listed below show you which variables you can use to adapt the control
response.
The basic procedure is described in the following section for STARTER and IOP.
● K
● T
Optimizing the closed-loop speed controller with STARTER and IOP
Procedure
To manually optimize the closed-loop speed controller with STARTER, proceed as follows:
1. Go online, and in the "Ramp-function generator" screen form, set the times = 0.
2. Set pre-control = 0 in the "Closed-loop speed controller" screen form.
3. Enter a setpoint step and monitor the associated actual value, e.g. using the trace
function in STARTER.
4. Optimize the closed-loop controller in the "Closed-loop speed controller" screen form by
adjusting the closed-loop controller parameters K
5. Set the ramp-up and ramp-down times of the ramp-function generator back to their
original value.
6. Set the pre-control of the closed-loop speed controller back to 100%.
Inverter cabinet units
Operating Instructions, 12/2014, A5E32923362A
(p1470) Proportion share
P
(p1472) Integration time
N
The actual value only slowly approaches
the setpoint.
• Increase the proportional component K
and reduce the integration time T
The actual value quickly approaches the
setpoint, but overshoots too much.
• Decrease the proportional component
K and increase the integration time T
P
and T .
P N
Functions
7.5 Motor control
P
.
N
.
N
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