H2 and H Infinity Optimization with a Restricted Region of Stability

Abstract

Many modern control design methods, such as H2 and H Infinity optimization, guarantee that the closed-loop system will be stable. To make further use of this guarantee, the portion of the s-plane considered to be stable is restricted to a region left of a vertical line some distance alpha from the imaginary axis. This alpha shift was accomplished in the state space equations, so standard computational tools still work. now the system is not only guaranteed to be stable, but also has some guaranteed speed for the time response. The equations for guaranteeing some arbitrary damping ratio were also derived in Cartesian coordinates, but only the alpha shift was put into the state space equation form and tested. The alpha shift increased the speed of the system, as expected. An additional benefit was increasing the damping of lightly damped poles. The cost for doing this was an increase in the steady state error and an increase in the control power required.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1990
Accession Number
ADA230596

Entities

People

  • Michael J. Mares

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Cartesian Coordinates
  • Closed Loop Systems
  • Control Surfaces
  • Control Systems
  • Engineering
  • Equations
  • Equations Of State
  • Guarantees
  • Mathematics
  • Multiple Input Multiple Output
  • Open Loop Systems
  • Standards
  • Steady State
  • Test And Evaluation
  • Transfer Functions
  • Weighting Functions

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Analytical Mechanics
  • Control Systems Engineering.

Technology Areas

  • Space
  • Space - Spacecraft Maneuvers