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Unformatted text preview: controller for a setpoint change using k c = 22.95 t I = 0 75 (ZN settings). ; . Figure 11: Closedloop response with a PI controller for a disturbance using k c = 22.95 t I = 0 75 (ZN settings). ; . Next, the stabilit y margins are calculated using the Bode Stabilit y Criterion for both gain and phase. The results are displayed in Figure 12 and they are 25 and 1.87 for the phase and gain margins, respect ively. Figure 13 illustrates the Bode diagram (including the stabilit y margins) for the case when the controller gain is reduced to 17 and maintaining the integral t ime constant value as before. Now, the stabilit y margins for the gain and phase are 2.53 and 33, respectively. This means that the system is more stable. Figures 14 and 15 illustrate the closedloop response of the system under the new settings for both setpoint and disturbances. As expected, the sys tem wit h reduced the controller gain shows decreased level o f oscillat ion wit h a reduction o f the overshoot without much deterioration in the speed o f...
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This note was uploaded on 01/12/2014 for the course CHE 4198 taught by Professor Hjortso,m during the Fall '08 term at LSU.
- Fall '08