Ascc04 334 Comparative Study of Unstable Process Control
1. A Comparative Study on Control of Unstable Processes with Time-delay Qing-Guo Wang, Han-Qin Zhou Department of Electrical & Computer Engineering National University of Singapore
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11. Simulation & Comparison 1. Small Normalized Dead-time: 0<L/T<0.693 The plant’s normalized dead-time is 0.5. A unity step setpoint is given at t = 0, and a disturbance of -0.1 is injected at t = 75.
14. Ranking ( Small Normalized Dead-time ) Setpoint Response Best: Method G Excellent: Method E and F Good: Method C and A Fair: Method B Poor: Method D Disturbance Rejection Excellent: Method E and F Good: Method C and A Fair: Method D and G Poor: Method B
15. Simulation & Comparison 2. Medium Normalized Dead-time: 0.693<L/T<1 The plant’s normalized dead-time is 0.8, Method B is no longer applicable. Again, the unity step setpoint is given at t = 0, and a disturbance of -0.1 is injected at t = 75.
17. Ranking ( Median Normalized Dead-time ) Setpoint Response Excellent: Method G Good: Method E and F Fair: Method C and A Poor: Method D Disturbance Rejection Excellent: Method A Good: Method E, F and C Fair: Method D Poor: Method G
18. Simulation & Comparison 3. Large Normalized Dead-time: 1<L/T<2 The plant’s normalized dead-time is 1.5. Only Method E and F are workable in this scenario. Again, the unity step setpoint is given at t = 0, and a disturbance of -0.1 is injected at t = 75.
19. Performance Specifications Ranking ( Large Normalized Dead-time ) Setpoint Response Method E is slightly better Disturbance Rejection Method F is slightly better