Proportional- Integrated-Derivative (PID) controllere er ofte brug af systemer til at vedligeholde likvide niveauer.

Basic System Parameters

Consider a level control system with there following parameters:

  • Process gain (K; K; 1; FLT: 0; 3; p; 1; FLT: 1; 3;) = 2
  • Process time constant (τ; τ; FLT: 0; 3; p; 1; FLT: 1; 3;) = 50 sekunder
  • Dead time (L) = 10 seconds

PID Parametr Calculation

Using the Ziegler- Nichols tuning method, the ultimate gain (K; 1; FLT: 0; 3; u; 1; FLT: 1; 3;) og ultimate period (T; 1; FLT: 2; 3; U; 1; FLT: 3; 3; 3;) are determined determinationally. Asseme:

  • K = 1; FLT = 3; u = 1; FLT: 1; FLT: 3; = 6
  • T-1; T-1; T-3; U-3; T-1; T-3; T-3; = 40 sekunder

PID parametrene er, at de beregnes efter følgende:

Proportional Gain (K; K; 1; FLT: 0; 3; p; 1; FLT: 1; 3;)

K = 1; T = 1; T: 0; P = 3; p = 1; T: 1; T: 1; 3; T = 3; = 0, 6 × K = 1; T: 2; T: 3; u = 1; T: 3; T: 3; T: 3; T: 3; 3; T: 3; = 3; = 0, 6 × 6 = 3, 6

Integral Time (T-1; FT: 0-3; I-1; FLT: 1-3;)

T-1; T-1; T-3; I-3; I-3; I-3; T-3; T-3; = 0-5 × T-1; T-1; T-2-3; U-3; T-3-3; T-3-3; T-3; T-3; = 0-5 × 40 = 20 sekunder

Derivative Time (T-1; FLT: 0-3; D-1; FLT: 1-3;)

T-1; T-1; T-3; D-3; D-1; T-3; T-3; = 0,125 × T-1; T-1; T-2: 3; U-3; T-1; T-3; T-3; T-3; T-3; T-3; = 0,125 × 40 = 5 sekunder

Final PID Settings

Denne tunede PID kontrollør parameters ar:

  • K = 1; FLT = 3; p = 1; FLT: 1; FLT: 3; = 3, 6
  • T-1; T-1; T-3; I-3; I-1; T-1; T-3; T-3; = 20 sekunder
  • T-1; T-1; T-3; D-3; D-1; T-1; T-3; T-3; = 5 sekunder