Large-Scale Systems: Optimality vs. Reliability

  • D. D. Siljak
  • S. K. Sundareshan


Optimal control systems may become unstable if subject to structural perturbations whereby parts of the system are disconnected (and again connected) during operation. Multi-level schemes for controlling large-scale linear systems are proposed in this work, which provide a trade-off between reliability and optimality. By treating the interconnections among subsystems as perturbation terms, a two-level control strategy is developed. Local controls are used to optimize the decoupled subsystems with respect to quadratic costs, and global controls are applied to minimize the effects of interconnections. Although this control scheme results in a sub- optimal performance, it is inherently reliable.


Global Control Structural Perturbation Gain Matrice Optimal Control System Positive Definite Solution 
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Copyright information

© Plenum Press, New York 1976

Authors and Affiliations

  • D. D. Siljak
    • 1
  • S. K. Sundareshan
    • 1
  1. 1.Department of Electrical Engineering & Computer ScienceUniversity of Santa ClaraSanta ClaraUSA

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