| 1. |
- Birk, Wolfgang, et al.
(author)
-
Control and gas leakage detection in a fine coal injection plant : design and experiments
- 1998
-
In: Automation in mining, mineral, and metal processing 1998, (MMM'98). - Oxford : Pergamon Press. ; , s. 261-266
-
Conference paper (peer-reviewed)abstract
- This paper deals with design and implementation of a combined model-based control and gas leakage detection system applied to the pulverized coal injection plant at SSAB Tunnplåt AB in Luleå, Sweden. The structure and functions of the in-house control and process monitoring system SafePCI are described. SafePCI is experimentally tested and has successfully completed two weeks test operation. The evaluation of the test operation indicate that combined model-based control and gas leakage detection is a major improvement for control systems in the process industry.
|
|
| 2. |
|
|
| 3. |
- Johansson, Andreas, et al.
(author)
-
Detection of incipient clogging in pulverized coal injection lines
- 1999
-
In: Conference record of the 1999 IEEE Industry Applications Conference. - Piscataway, NJ : IEEE Communications Society. - 078035589X ; , s. 1329-1335
-
Conference paper (peer-reviewed)abstract
- This paper deals with the detection of clogging in the coal injection lines of a blast furnace. A physical model is developed and augmented with a signal that represents clogging. An observer is proposed and shown to have any predefined convergence rate. An adaptive detection threshold scheme which is robust against time-varying uncertainties is employed. Simulations and experiments with real data are carried out to illustrate the usefulness of the methods.
|
|
| 4. |
- Johansson, Andreas, et al.
(author)
-
Model-based gas leakage detection and isolation in a pressurized system via Laguerre spectrum analysis
- 1998
-
In: Proceedings of the 1998 IEEE International Conference on Control Applications. - Piscataway, NJ : IEEE Communications Society. - 078034104X ; , s. 212-216
-
Conference paper (peer-reviewed)abstract
- This paper deals with gas-leakage detection and isolation in a fine coal injection vessel for a blast furnace process. Functions describing the expected time-domain behaviour of different leakages are developed, thus reducing the leakage isolation problem to pattern recognition. In order to lower the computational burden while preserving the essential dynamic behaviour of a leakage, a truncated Laguerre series representation is used. The Generalized Likelihood Ratio methos is employed to compare the Laguerre of the residual with the Laguerre spectra of the predefined typical leakage functions. Tests of the developed algorithm have been successfully performed at SSAB Tunnplåt, Luleå.
|
|
| 5. |
- Johansson, Andreas, et al.
(author)
-
Model-based leakage detection in a pulverized coal injection vessel
- 1998
-
In: Proceedings of the 1998 American Control Conference, ACC, June 24 - 26, 1998, Philadelphia, Pennsylvania, USA. - Piscataway, NJ : IEEE Communications Society. - 0780345304 ; , s. 1742-1746
-
Conference paper (peer-reviewed)abstract
- A method for detecting and isolating incipient leakages in the valves of a pulverized coal injection vessel for a blast furnace process is presented. Non-linear physical gray-box models of the plant are developed. Values of the unknown parameters are estimated by identification. Observers are constructed for these models and the residuals are used in a Generalized Likelihood Ratio test. The method is successfully tested with real leakages intentionally introduced in the plant.
|
|
| 6. |
- Johansson, Andreas, et al.
(author)
-
Model-based leakage detection in a pulverized coal injection vessel
- 1999
-
In: IEEE Transactions on Control Systems Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 1063-6536 .- 1558-0865. ; 7:6, s. 675-682
-
Journal article (peer-reviewed)abstract
- A method for detecting and isolating incipient leakages in the valves of a pulverized coal injection vessel for a blast furnace process is presented. Nonlinear physical gray-box models of the plant are developed. Values of the unknown parameters are estimated by identification. Observers are constructed for these models and the residuals are used in a generalized likelihood ratio test. The method is successfully tested with real leakages intentionally introduced in the plant.
|
|
| 7. |
- Johansson, Karl H., et al.
(author)
-
Teaching multivariable control using the Quadruple-Tank Process
- 1999
-
In: Proceedings of the 38th IEEE Conference on Decision and Control, 1999. - : IEEE. ; , s. 807-812
-
Conference paper (peer-reviewed)abstract
- A multivariable laboratory process is presented together with its use in a graduate control course. The process is called the quadruple-tank process and demonstrates a multivariable level control problem. The multivariable zero dynamics of the system can be made both minimum phase and nonminimum phase by simply changing a valve. This makes the quadruple-tank process suitable for illustrating many concepts in linear and nonlinear multivariable control. In the paper some of these are described together with the basic setup of the process. Two computer exercises and one laboratory exercise have been developed as part of a course in multivariable and nonlinear control. These are detailed and some experience from the course is presented.
|
|
