The nonlinear systems under consideration in this paper are described by differential equations. In the same way as for linear systems, it has system state variables, inputs and outputs. The paper provides basic definitions for state space models of nonlinear systems, and tools for preliminary analysis, including linearisation around operating points. Typical nonlinear behaviours such as limit cycles and chaos are also discussed with examples.

Chapter Contents:

• 2.1 Nonlinear systems and linearisation around an operating point
• 2.2 Autonomous systems
• 2.3 Second-order nonlinear system behaviours
• 2.4 Limit cycles and strange attractors

Inspec keywords: nonlinear control systems; state-space methods; linear systems; differential equations; linearisation techniques; control system analysis

Other keywords: nonlinear system; linear system; linearisation; state space model; differential equation; preliminary analysis; limit cycle behavior; system output; chaos behavior; system state variable; system input

Subjects: Control system analysis and synthesis methods; Nonlinear control systems; Mathematical analysis