FLOW RATE CONTROL SYSTEM SECOND ORDER PLUS DEAD TIME MODEL April 20, 2006 U.T.C Engineering 329
Yellow Team Jimy George Jeff Lawrence Taylor Murphy Jennifer Potter
Outline Flow System Background SOPDT System Theory Model Results
Outline Proportional Controller Comparison of FOPDT & SOPDT results Conclusion
Flow System Setup
Block Diagram
Laplace Domain R(s) C(s)
Time Domain
Modeling Observations
Parameters involved
Modeling Observations Recap
Negative Feedback Loop
Closed Loop Transfer Function
Characteristic Equation
Characteristic Equation For
Solving CE for Kc Direct Substitution Set s = iωU Set like terms equal to zero Imaginary part: [0.0079 ωU3-(0.6 +0.048Kcu) ωU]i=0i
Direct Substitution (cont’d) Real part: 0.24Kcu - 0.12 ωU2 + 1 = 0 ωU = 5 => fu = 0.8 Kcu = 8.3 %/(lb/min)
Corresponding Frequency Experiment
Observations Phase Angle = -1800 Amplitude Ratio = 0.12 Kcu calculated = 8.3
Comparison of fu
Comparison of Kc
Conclusion Kc = 8.3 %/(lb/min) SOPDT more accurate than FOPDT Always scope for improved results