Location of Repository

Robust Multi-Mode Control of High Performance Aero-Engines

By Raza Samar


This thesis describes the application of H∞ design techniques to the control of high performance aero-engines. The design study presented is practical and realistic, the work being motivated by problems that arise naturally in real engineering situations. The aero-engine is multivariable and highly nonlinear: the dynamics vary considerably with the thrust being produced, and with the altitude and forward speed of the aircraft. Moreover, there are operational constraints that must never be violated for reasons of safety: certain engine variables should always be limited to safe vales. Furthermore, not all the engine parameters to be controlled are directly measurable; instead a number of related measurements are available. A methodology is presented to choose from the available measurements, those that are preferable for feedback control. Different techniques of model reduction using balanced realizations are considered. Two illustrative examples are presented, and the methods compared in detail. Explicit state-space formulae for an H∞-based two degrees-of-freedom robust controller are derived in discrete time. The controller provides robust stability with respect to coprime factor perturbations, and a degree of robust performance in the sense of making the closed-loop system match an ideal reference model. Special attention is paid to the structure of the controller. It is shown that the controller consists of a plant observer, the reference model, and a generalized state feedback law associated with the plant and model states. Multi-mode control logic is developed to ensure that safety limits are never violated. Actual engine test results are presented for sea-level static conditions. All the different modes of operation are tested.\ud Full flight envelope evaluation of the controller is carried out using a nonlinear engine simulation. The robust performance of the controller is demonstrated and comparisons made with existing engine control systems

Publisher: University of Leicester
Year: 1995
OAI identifier: oai:lra.le.ac.uk:2381/10006

Suggested articles



  1. (1990). A comparison of different H∞ methods in VSTOL flight control system design. doi
  2. (1991). A comparison of different scheduling techniques for H∞ controllers. doi
  3. (1987). A Course in H∞ Control Theory, doi
  4. (1993). A decentralized control scheme for a high performance turbine. doi
  5. (1995). A digital multi-mode H∞ controller for the Spey turbofan engine. doi
  6. (1995). A discrete time H∞ observerbased controller & its application to an aero-engine. doi
  7. (1990). A J-spectral factorization approach to H∞ control. doi
  8. (1992). A loop shaping design procedure using H∞ synthesis. doi
  9. (1992). A procedure for controllability analysis. doi
  10. (1994). A unified framework for the study of anti-windup designs. doi
  11. (1992). Aircraft Engines and Gas Turbines. doi
  12. (1984). All optimal Hankel-norm approximations of linear multivariable systems and their L∞-error bounds. doi
  13. (1991). An H∞ approach to two degree of freedom design. doi
  14. (1989). Analysis and design for ill-conditioned plants–Part 1. Lower bounds on the structured singular value. doi
  15. Analysis of feedback systems with structured uncertainties. doi
  16. (1994). Applications of the singular perturbation approximation of balanced systems. doi
  17. (1985). Beyond singular values and loop shapes. doi
  18. (1988). CACSD using the state-space L∞ theory—a design example. doi
  19. (1986). Closed loop control of an afterburning F100 gas turbine engine.
  20. (1984). Computer Controlled Systems: Theory and Design. doi
  21. (1987). Conditioning technique, a general anti-windup and bumpless transfer method. doi
  22. (1991). Continuous scheduling of H∞ controllers for a MS760 Paris aircraft.
  23. (1991). Control configuration design for a mixed vectored thrust ASTOVL aircraft in hover. doi
  24. (1989). Control of constrained multivariable systems using the conditioning technique.
  25. (1979). Control system design and analysis using closed-loop nyquist and bode arrays. doi
  26. (1985). Control System Synthesis: A Factorization Approach. doi
  27. (1992). Control System Toolbox for use with Matlab: User’s Guide. The MathWorks,
  28. (1989). Controller reduction: Concepts and approaches. doi
  29. (1986). Design examples using µ-synthesis: Space shuttle lateral axis FCS during reentry. doi
  30. (1984). Design of nonlinear multivariable feedback controls by total synthesis. doi
  31. (1991). Design of robust controllers for gas turbine engines. doi
  32. (1986). Design of tunable digital set-point tracking PI controllers using step-response matrices for gas turbines. doi
  33. (1986). Development of QSK-06 full authority digital electronic control for gas turbines.
  34. (1990). Digital Control of Dynamic Systems.
  35. (1991). Discrete time H∞ control laws for a high performance helicopter. doi
  36. (1989). Discrete time H∞ control. doi
  37. (1994). EPSRC/LUCAS Research Programme: Engine Control Specification (Amended).
  38. (1992). EPSRC/LUCAS Research Programme: Engine Control Specification.
  39. (1987). Euclidean condition and block relative gain: Connections, conjectures, and clarifications. doi
  40. Excerpts from a forthcoming book on µ.
  41. (1981). Feedback and optimal sensitivity: Model reference transformations, multiplicative seminorms, and approximate inverses. doi
  42. (1991). Feedback Control of Dynamic Systems.
  43. (1975). Feedback Systems: Input-Output Properties. doi
  44. (1983). Feedback, minimax sensitivity, and optimal robustness. doi
  45. (1985). Frequency-weighted optimal Hankel-norm approximation of stable transfer functions. doi
  46. (1984). Gain-scheduled multivariable control for the GE-21 turbofan engine using the LQR and LQG/LTR methodologies. Master’s thesis,
  47. (1981). Gas Turbine Engineering: Applications, Cycles and Characteristics. doi
  48. (1987). Gas Turbine Theory.
  49. (1994). Gauge control in tandem cold rolling mills: A multivariable case study using H∞ optimization. doi
  50. (1978). Guaranteed margins for LQG regulators. doi
  51. (1993). H∞ control of gasturbine engines for helicopters.
  52. (1987). H∞ control system design: A critical assessment based on industrial applications.
  53. (1992). H∞ controller synthesis by J-lossless coprime factorization. doi
  54. (1991). H∞ robust control synthesis for a large space structure. doi
  55. (1987). Implications of large RGA elements on control performance. doi
  56. (1986). Industrial control system design using H∞ optimization. doi
  57. (1988). Integrated design/implementation of nonlinear digital controllers.
  58. (1989). Integrator windup and how to avoid it.
  59. (1986). Interaction measures for systems under decentralized control. doi
  60. (1995). Linear Robust Control. doi
  61. (1986). Linear-quadratic Gaussian with loop transfer recovery methodology for the F-100 engine. doi
  62. (1984). Model Reduction for Control System Design.
  63. (1994). Model reduction in aeroengine control. doi
  64. Model reduction via balanced state space representations. doi
  65. (1984). Model reduction with balanced realizations: An error bound and a frequency weighted generalization. doi
  66. (1995). Model reduction with balanced realizations. doi
  67. (1989). Multivariable anti-windup and bumpless transfer: A general theory.
  68. (1991). Multivariable control by individual channel design: An automotive gas turbine case study. doi
  69. (1986). Multivariable control of the GE T700 engine using the LQG/LTR design methodology. doi
  70. (1994). Multivariable controller design for a high performance aero-engine. doi
  71. (1993). Multivariable controller design for a turbofan engine. doi
  72. (1981). Multivariable feedback design: Concepts for a classical/modern synthesis. doi
  73. (1989). Multivariable Feedback Design. doi
  74. (1994). Multivariable powerplant control - proof of concept.
  75. (1988). Multivariable turbofan engine control for full flight envelope operation. doi
  76. (1993). On the design of robust two degree of freedom controllers. doi
  77. On the structure of a 2-degree-of-freedom feedback controller. doi
  78. (1982). Performance and robustness analysis for structured uncertainty. doi
  79. (1990). Plant directionality, coupling and multivariable loop-shaping. doi
  80. (1992). Pole-zero cancellations and closedloop properties of an H∞ mixed sensitivity design problem. doi
  81. (1990). Pole/zero cancellations in the general H∞ problem with reference to a two block design. doi
  82. (1981). Principal component analysis in linear systems: Controllability, observability, and model reduction. doi
  83. (1993). Robust control of a glass tube shaping process.
  84. (1995). Robust control of an unknown plant–the IFAC 93 benchmark. doi
  85. (1991). Robust Control of Discrete Time Systems. doi
  86. (1988). Robust control of ill-conditioned plants: High-purity distillation. doi
  87. (1990). Robust control of processes subject to saturation nonlinearities. doi
  88. (1993). Robust control of the benchmark problem using H∞ methods and numerical optimisation techniques. doi
  89. (1992). Robust Control Toolbox: User’s Guide. The MathWorks,
  90. (1994). Robust controller design using H∞ loop-shaping and the method of inequalities. doi
  91. (1990). Robust Controller Design Using Normalized Coprime Factor Plant Descriptions, doi
  92. (1993). Robust instability control of ITER plasmas. doi
  93. (1989). Robust Process Control. doi
  94. (1990). Robust stabilizability of discrete-time systems with normalized stable factor perturbation. doi
  95. (1989). Robust stabilization of normalized coprime factor plant descriptions with H∞-bounded uncertainty. doi
  96. (1979). Robustness with observers. doi
  97. (1985). Robustness with simultaneous pole and zero movement across the jω-axis. doi
  98. (1993). Rotorcraft flying qualities improvement using advanced control.
  99. (1990). Scheduling by switching of H∞ controllers for a VSTOL aircraft. doi
  100. (1992). Simple frequency-dependent tools for control system analysis, structure selection and design. doi
  101. (1989). Singular perturbation approximation of balanced systems. doi
  102. (1993). Some control problems in the process industries. doi
  103. (1988). Stable H – an H∞ control-system design package. doi
  104. (1991). State-space approach to discrete-time H∞ control. doi
  105. (1988). State-space formulae for all stabilizing controllers that satisfy an H∞-norm bound and relations to risk sensitivity. doi
  106. (1989). State-space solutions to standard H2 and H∞ control problems. doi
  107. (1985). Structured uncertainty in control system design. doi
  108. (1993). Taking H∞ control into flight. doi
  109. (1992). The application of multivariable control to a turbofan engine. doi
  110. (1991). The Application of Robust Control to VSTOL Aircraft. PhD thesis,
  111. (1994). The role of the condition number and the relative gain array in robustness analysis. doi
  112. (1986). Weighted Hankel-norm approximation: Calculation of bounds. doi
  113. (1990). Weighting function selection in H∞ design. doi
  114. (1991). µ-Analysis and Synthesis Toolbox: User’s Guide. The MathWorks,

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.