Singular Perturbation of Nonlinear Regulators and Systems with Oscillatory Modes.

Abstract

This report applies singular perturbation techniques to nonlinear optimal control problems and systems with high frequency oscillatory behavior. For a class of nonlinear regulator problems the Hamilton-Jacobi equation is solved as a power series expansion whose coefficients are solved from equations involving the slow variables only. Consequently we obtain near-optimal feedback controls. Through the construction of a composite Lyapunov function, these controls can stabilize large disturbances of the fast variables. A fixed endpoint nonlinear control problem is decomposed into three lower order problems, namely, the nonlinear reduced order problem and the linear quadratic left and right boundary layer problems. For systems with high frequency oscillatory behavior, the original system is decomposed into a slowly varying system and a fast oscillatory system. This procedure provides physical interpretations for the high frequency oscillations occurring in a mass-spring-damper system and an interconnected power system.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1977
Accession Number
ADA057644

Entities

People

  • Joe H. Chow

Organizations

  • University of Illinois Urbana–Champaign

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Asymptotic Series
  • Boundary Layer
  • Boundary Value Problems
  • Closed Loop Systems
  • Control Systems
  • Differential Equations
  • Engineering
  • Equations
  • Feedback
  • Frequency
  • Linear Systems
  • Lyapunov Functions
  • Nonlinear Systems
  • Partial Differential Equations
  • Power Series
  • Regulators

Fields of Study

  • Mathematics
  • Physics

Readers

  • Control Systems Engineering.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Operations Research