208
can be realized via X terminal. The running direction is the direction determined by the running command; if
the direction is uncertain, then follow the direction of last section.
6.15 Process PID parameters (Group P14)
The PID closed loop control adopts the combinations of proportional control (P), integral control (I) and
differential control (D). This is a control mode which makes the feedback value consistent with the target
value.
Proportional control (P)
The control quantity in proportion to the deviation cannot only rely on P control to eliminate steady-state
error.
Integral control (I)
The control quantity in proportion to the deviation integral value can eliminate steady-state error, but it
cannot control sharp change.
Differential control (D)
The control quantity in proportion to the deviation change rate can predict the change tendency of the
deviation, quickly response to sharp change and improve dynamic performance, but it is vulnerable to
interference, so use D control only when necessary. The PID control block diagram is as shown in Fig.
6-72.
To Next Page
Loading...