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Installation, Operation, & Maintenance Manual
ES-09374-1
Figure 8-22 PI Control Chart
Derivative Control
The derivative action like the integral action works with time (Td) and is also used in
conjunction with the proportional action (PD control).
This control is very efficient with respect to correction because it starts the correction
immediately as soon as the error starts (as the derivation of constant is always zero).
As in PI control this control also suffers effects for very high or very low values for time
(Td).
When we have large times, we will have more stability in the system with low-speed
response.
And when the time is small, there are many oscillations and falls in the stability of the
loop.
The PD control has the same peculiarity of proportional control only, which is to leave a
residue that is called offset, even though the derivative action improves the stability of
the system.
Graphically the PD control is like PI control differing only by leaving an offset.
Figure 8-23
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Configuration
August 23, 2022
Configuration
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