IFM Electronic Ecomat Mobile Series, Системное руководство

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ifm System Manual ecomat mobile SmartController (CR2500) V05
Controller functions in the ecomatmobile controller General
11 Controller functions in the ecomatmobile
controller
General ................................................................................................................................... 256
Setting rule for a controller ..................................................................................................... 258
Functions for controllers ......................................................................................................... 259
11.1 General
Controlling is a process during which the unit to be controlled (control variable x) is continuously
detected and compared with the reference variable w. Depending on the result of this comparison, the
control variable is influenced for adaptation to the reference variable.
Regeleinrichtung
Controller
Regelstrecke
Controlled system
Störgröße d
Disturbance variable d
Regelkreis / Control circuit
Regelgröße x
Controlled variable x
Führungsgröße w
Reference variable w
Stellgröße y
Manipulated variable y
Figure: Principle of controlling
The selection of a suitable control device and its optimum setting require exact indication of the
steady-state behaviour and the dynamic behaviour of the controlled system. In most cases these
characteristic values can only be determined by experiments and can hardly be influenced.
Three types of controlled systems can be distinguished:
11.1.1 Self-regulating process
For a self-regulating process the control variable x goes towards a new final value after a certain
manipulated variable (steady state). The decisive factor for these controlled systems is the
amplification (steady-state transfer factor KS). The smaller the amplification, the better the system can
be controlled. These controlled systems are referred to as P systems (P = proportional).
Figure: P controller = self-regulating process