Woodward SPM-D11, Руководство пользователя

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Manual 37259C SPM-D11 - Synchronizing Unit
Overshoot x
m
:
Highest transient deviation from the set point value during the transition from one steady-state
condition to a new steady-state condition, following a change in value of the disturbance variable or reference
input variable (x
m Optimal
≤
10 %).
Permanent control deviation x
d
:
The resultant deviation between set point value and output variable in the
steady-state condition (PID controller: x
d
= 0).
From these values, the values K
P
, T
n
and T
V
can be derived. It is possible, to determine the optimal controller set-
tings by calculating compensation or adjustment of the time constants, T-sum rule, or symmetrical optimum.
Other setting procedures and information may be obtained from current literature.
CAUTION
The following must be observed regarding the controller setting:
•
Ensure that the emergency shutdown system is ready for use.
•
While determining the critical frequency, pay attention to the amplitude and frequency.
•
If the two values change in an uncontrollable manner:
Î
EMERGENCY SHUTDOWN
Í
Initial state:
The initial state determines the start position of the controller. If the controller is switched off, the
initial state can be used to output a fixed controller position. Even when the analog controller is switched off, the
initial state can be freely adjusted (e.g. the speed controller can be controlled in a static manner).
Controller output
Initial state 000%
Initial state 0 to 100 %
Analog controller output setting with controller switched off.
General settings:
The setting rule described below only serves as an example. Whether this method is suitable
for setting your particular control system is not and cannot be taken into account, as each controlled system be-
haves uniquely.
There are various methods of setting a controller. The setting rules of Ziegler and Nichols are explained below
(determination for abrupt disturbances on the system input); this setting method assumes a pure lag element con-
nected in series with a first-order lag system.
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