Preliminary Heat Exchanger Control Design Study Steve Rogers 9 April 2011
Table of Contents Preliminary Heat Exchanger Control Design Study......................................................................................1 Table of Contents........................................................................................................................................1 Introduction.............................................................................................................................................1 Operating Conditions...............................................................................................................................2 Model Linearization.................................................................................................................................2 Simulink Dynamic Model.........................................................................................................................3 Pole Placement Method..........................................................................................................................4 LQR Method...........................................................................................................................................11 Optimization Using LQR.........................................................................................................................15 Conclusions............................................................................................................................................16 Appendix................................................................................................................................................17 Appendix – operating condition 1..........................................................................................................17 Appendix – operating condition 2..........................................................................................................19 Appendix – operating condition 3..........................................................................................................20 Appendix – operating condition 4..........................................................................................................21 Appendix – Genetic Algorithm Optimizer..............................................................................................22
Introduction Air bleed control systems for jet engines involve pressure, flow, and temperature regulation. Heat exchangers, control valves, and sensor suites are components of the system to be regulated. Ordinarily a cascade control system is used, with flow/pressure on the inner loop and temperature on the outer loop. The classical approach is to close one loop at a time starting with the inner loop. This study shows how a modern approach will close both loops simultaneously. We will show 4 different operating conditions. Solutions will be by pole placement and LQR (modern methods). In order to speed up development, optimization may be used to determine the weighting for the control laws. In this case we chose the LQR for optimization. We limited the parameter optimization to 11
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