Time-delay estimation for nonlinear systems with piecewise-constant input
We consider a general nonlinear time-delay system in which the input signal is piecewise-constant. Such systems arise in a wide range of industrial applications, including evaporation and purification processes and chromatography. We assume that the time-delays—one involving the state variables and...
| Main Authors: | , , , |
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| Format: | Journal Article |
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Elsevier Inc.
2013
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| Online Access: | http://hdl.handle.net/20.500.11937/22951 |
| _version_ | 1848751016302870528 |
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| author | Chai, Q. Loxton, Ryan Teo, Kok Lay Yang, C. |
| author_facet | Chai, Q. Loxton, Ryan Teo, Kok Lay Yang, C. |
| author_sort | Chai, Q. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | We consider a general nonlinear time-delay system in which the input signal is piecewise-constant. Such systems arise in a wide range of industrial applications, including evaporation and purification processes and chromatography. We assume that the time-delays—one involving the state variables and the other involving the input variables—are unknown and need to be estimated using experimental data. We formulate the problem of estimating the unknown delays as a nonlinear optimization problem in which the cost function measures the least-squares error between predicted and measured system output. The main difficulty with this problem is that the delays are decision variables to be optimized, rather than fixed values. Thus, conventional optimization techniques are not directly applicable. We propose a new computational approach based on a novel algorithm for computing the cost function’s gradient. We then apply this approach to estimate the time-delays in two industrial chemical processes: a zinc sulphate purification process and a sodium aluminate evaporation process. |
| first_indexed | 2025-11-14T07:46:01Z |
| format | Journal Article |
| id | curtin-20.500.11937-22951 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T07:46:01Z |
| publishDate | 2013 |
| publisher | Elsevier Inc. |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-229512019-02-19T04:25:44Z Time-delay estimation for nonlinear systems with piecewise-constant input Chai, Q. Loxton, Ryan Teo, Kok Lay Yang, C. Evaporation processes Parameter identification Purification processes Time-delay system Nonlinear optimization We consider a general nonlinear time-delay system in which the input signal is piecewise-constant. Such systems arise in a wide range of industrial applications, including evaporation and purification processes and chromatography. We assume that the time-delays—one involving the state variables and the other involving the input variables—are unknown and need to be estimated using experimental data. We formulate the problem of estimating the unknown delays as a nonlinear optimization problem in which the cost function measures the least-squares error between predicted and measured system output. The main difficulty with this problem is that the delays are decision variables to be optimized, rather than fixed values. Thus, conventional optimization techniques are not directly applicable. We propose a new computational approach based on a novel algorithm for computing the cost function’s gradient. We then apply this approach to estimate the time-delays in two industrial chemical processes: a zinc sulphate purification process and a sodium aluminate evaporation process. 2013 Journal Article http://hdl.handle.net/20.500.11937/22951 10.1016/j.amc.2013.03.015 Elsevier Inc. fulltext |
| spellingShingle | Evaporation processes Parameter identification Purification processes Time-delay system Nonlinear optimization Chai, Q. Loxton, Ryan Teo, Kok Lay Yang, C. Time-delay estimation for nonlinear systems with piecewise-constant input |
| title | Time-delay estimation for nonlinear systems with piecewise-constant input |
| title_full | Time-delay estimation for nonlinear systems with piecewise-constant input |
| title_fullStr | Time-delay estimation for nonlinear systems with piecewise-constant input |
| title_full_unstemmed | Time-delay estimation for nonlinear systems with piecewise-constant input |
| title_short | Time-delay estimation for nonlinear systems with piecewise-constant input |
| title_sort | time-delay estimation for nonlinear systems with piecewise-constant input |
| topic | Evaporation processes Parameter identification Purification processes Time-delay system Nonlinear optimization |
| url | http://hdl.handle.net/20.500.11937/22951 |