Title
Parameter estimation for nonlinear time-delay systems with noisy output measurements
Abstract
This paper considers the problem of using noisy output data to estimate unknown time-delays and unknown system parameters in a general nonlinear time-delay system. We formulate the problem as a dynamic optimization problem in which the unknown quantities are decision variables to be chosen optimally, with the cost function penalizing the mean and variance of the least-squares error between actual and predicted system output. Since the time-delays and system parameters influence the cost function implicitly through the governing time-delay system, the cost function's gradient-which is required to solve the problem using gradient-based optimization techniques-cannot be computed analytically using standard differentiation rules. We instead develop two computational methods for evaluating this gradient: one involves solving an auxiliary time-delay system forward in time; the other involves solving an auxiliary time-advance system backward in time. On this basis, we propose an efficient optimization algorithm for determining optimal estimates for the time-delays and system parameters. We conclude the paper by examining the performance of this algorithm on a dynamic model of a continuously-stirred tank reactor.
Year
DOI
Venue
2015
10.1016/j.automatica.2015.06.028
Automatica
Keywords
Field
DocType
Time-delay,Nonlinear system,Parameter estimation,Dynamic optimization,Nonlinear optimization
Decision variables,Mathematical optimization,Nonlinear system,Control theory,Nonlinear programming,Optimization algorithm,Estimation theory,Optimization problem,Mathematics
Journal
Volume
Issue
ISSN
60
C
0005-1098
Citations 
PageRank 
References 
6
0.47
9
Authors
4
Name
Order
Citations
PageRank
Qun Lin1586.41
R.C. Loxton213016.50
Chao Xu313633.20
K. L. Teo41643211.47