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  • Output-only identification of self-excited systems using discrete-time Lur'e models with application to a gas-turbine combustor
Title: Output-only identification of self-excited systems using discrete-time Lur'e models with application to a gas-turbine combustor
A self-excited system is a nonlinear system with the property that a constant input yields a bounded, nonconvergent response. Nonlinear identification of self-excited systems is considered using a Lur'e model structure, where a linear model is connected in feedback with a nonlinear feedback function. To facilitate identification, the nonlinear feedback function is assumed to be continuous and piecewise affine (CPA). The present paper uses least-squares optimization to estimate the coefficients of the linear dynamics and the slope vector of the CPA nonlinearity, as well as mixed-integer optimization to estimate the order of the linear dynamics and the breakpoints of the CPA function. The proposed identification technique requires only output data, and thus no measurement of the constant input is required. This technique is illustrated on a diverse collection of low-dimensional numerical examples as well as data from a gas-turbine combustor.  more » « less
Award ID(s):
1634709
NSF-PAR ID:
10382861
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
International Journal of Control
ISSN:
0020-7179
Page Range / eLocation ID:
1 to 26
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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