Chapter 4
PID Synthesis
Xmath Interactive Control Design Module
4-2
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Toggling Controller Terms On and Off
For each parameter, the toggle button at the left of the row is used to toggle
the terms on and off. “On” means that the corresponding controller term
appears in the overall controller transfer function, and the slider and
variable edit box can be used to change the parameter. “Off” means that the
controller term does not appear in the overall controller transfer function.
In this case, the slider and the variable-edit box are read-only—you cannot
drag the slider, and you cannot type in the variable-edit box. When the
button is turned on again, the parameter value is restored to its previous
value. You can use the buttons to do a quick A/B comparison of a PID
controller with or without a given term—for example, to see the effect of
a high frequency rolloff term or integral action.
HF rolloff 1
HF rolloff time 1
T
hf
1
1 + 1/
(sT
hf
1
)
HF rolloff 2
HF rolloff time 2
T
hf
2
1 + 1/(
sT
hf
2
)
Table 4-1.
PID Controller Terms and Parameters (Continued)
Term
Parameter
Symbol
Controller