Design of Nonlinear Observer by Using Augmented Linear System based on Formal Linearization of Polynomial Type

The objective of this study is to propose an observer design for nonlinear systems by using an augmented linear system derived by application of a formal linearization method. A given nonlinear differential equation is linearized by the formal linearization method which is based on Taylor expansion considering up to the higher order terms, and a measurement equation is transformed into an augmented linear one. To this augmented dimensional linear system, a linear estimation theory is applied and a nonlinear observer is derived. As an application of this method, an estimation problem of transient state of electric power systems is studied, and its numerical experiments indicate that this observer design shows remarkable performances for nonlinear systems.

• Kazuo Komatsu
• Hitoshi Takata

• nonlinear system
• augmented linear system
• nonlinear observer
• formal linearization
• electric power system.

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