Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983078
I. Raptis, G. Vachtsevanos
Maintenance of critical or/complex systems has recently moved from traditional preventive maintenance to Condition Based Maintenance (CBM) exploiting the advances both in hardware (sensors / DAQ cards, etc) and in software (sophisticated algorithms blending together the state of the art in signal processing and pattern analysis). Along this path, Environmental Control Systems and other critical systems/processes can be improved based on concepts of anomaly detection and fault diagnosis are presented in this paper. The enabling technologies borrow from the fields of modeling, data processing, Bayesian estimation theory and in particular a technique called particle filtering. The efficiency of the diagnostic approach is demonstrated via simulation results.
{"title":"A health management framework for Environmental Control Systems","authors":"I. Raptis, G. Vachtsevanos","doi":"10.1109/MED.2011.5983078","DOIUrl":"https://doi.org/10.1109/MED.2011.5983078","url":null,"abstract":"Maintenance of critical or/complex systems has recently moved from traditional preventive maintenance to Condition Based Maintenance (CBM) exploiting the advances both in hardware (sensors / DAQ cards, etc) and in software (sophisticated algorithms blending together the state of the art in signal processing and pattern analysis). Along this path, Environmental Control Systems and other critical systems/processes can be improved based on concepts of anomaly detection and fault diagnosis are presented in this paper. The enabling technologies borrow from the fields of modeling, data processing, Bayesian estimation theory and in particular a technique called particle filtering. The efficiency of the diagnostic approach is demonstrated via simulation results.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"22 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114112349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983022
C. Bechlioulis, G. Rovithakis
An approximation free controller is designed for strict feedback systems, in the presence of unknown nonlinearities, time-varying parameters and exogenous disturbances, capable of guaranteeing, for any a priori known initial state condition, bounded signals in the closed loop, as well as prescribed performance for the output tracking error. By prescribed performance we mean that the output tracking error converges to a predefined arbitrarily small residual set, with convergence rate no less than a certain prespecified value, exhibiting maximum overshoot less than some sufficiently small preassigned constant. The proposed control scheme is of low complexity and requires reduced levels of a priori system knowledge.
{"title":"Robust approximation free prescribed performance control","authors":"C. Bechlioulis, G. Rovithakis","doi":"10.1109/MED.2011.5983022","DOIUrl":"https://doi.org/10.1109/MED.2011.5983022","url":null,"abstract":"An approximation free controller is designed for strict feedback systems, in the presence of unknown nonlinearities, time-varying parameters and exogenous disturbances, capable of guaranteeing, for any a priori known initial state condition, bounded signals in the closed loop, as well as prescribed performance for the output tracking error. By prescribed performance we mean that the output tracking error converges to a predefined arbitrarily small residual set, with convergence rate no less than a certain prespecified value, exhibiting maximum overshoot less than some sufficiently small preassigned constant. The proposed control scheme is of low complexity and requires reduced levels of a priori system knowledge.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"8 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131486664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983118
Mihai Iacob, G. Andreescu, R. Antal, A. Dan
This paper presents a centralized multivariable adaptive decoupling control using hardware-in-the-loop (HIL) for a boiler-turbine system. The boiler-turbine mathematical model is a 3×3 nonlinear strongly-coupled MIMO system with hard constraints. The proposed control strategy employs decoupling technique, gain scheduling with dynamic model linearization, and adaptive PID control with filtered updated gains and anti-windup to improve system response quality. The HIL concept splits the system into two sections, i.e., the simulation of the boiler-turbine model in LabView with graphical user interface (GUI) on PC, and the implementation of the control algorithms on real-time control target as programmable logic controller (PLC). The data exchange between the PC and PLC is provided by an OLE for Process Control (OPC) Server through Ethernet protocol. The synchronization between a real-time controller and a non real-time operating system (PC under Windows) is presented.
{"title":"Multivariable adaptive control with hardware-in-the-loop for a drum-type boiler-turbine system","authors":"Mihai Iacob, G. Andreescu, R. Antal, A. Dan","doi":"10.1109/MED.2011.5983118","DOIUrl":"https://doi.org/10.1109/MED.2011.5983118","url":null,"abstract":"This paper presents a centralized multivariable adaptive decoupling control using hardware-in-the-loop (HIL) for a boiler-turbine system. The boiler-turbine mathematical model is a 3×3 nonlinear strongly-coupled MIMO system with hard constraints. The proposed control strategy employs decoupling technique, gain scheduling with dynamic model linearization, and adaptive PID control with filtered updated gains and anti-windup to improve system response quality. The HIL concept splits the system into two sections, i.e., the simulation of the boiler-turbine model in LabView with graphical user interface (GUI) on PC, and the implementation of the control algorithms on real-time control target as programmable logic controller (PLC). The data exchange between the PC and PLC is provided by an OLE for Process Control (OPC) Server through Ethernet protocol. The synchronization between a real-time controller and a non real-time operating system (PC under Windows) is presented.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127930743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983051
C. Pop, R. D. De Keyser, C. Ionescu
Time delays in multivariable nonsquare systems challenge the control action, firstly by limiting the degree of freedom and secondly because of the interaction that exists between various input-output channels. Different decoupling techniques associated with multivariable Smith Predictors have been proposed for the control of such plants. The design of the primary controller has also been intensively studied. The method proposed in this paper is a straightforward alternative to previously designed control structures for multivariable stable nonsquare time delay processes. The authors show that in this way the task of designing the controller is much simplified, while the overall performance of the closed loop system remains the same. Further, the control design is suitable for a general class of stable multivariable processes, rather than the limited applicability of the original method to processes that can be described by first order time delay transfer functions. Setpoint tracking, disturbance rejection and robustness tests are presented in comparison with the original method to prove the efficiency of the proposed simplified method.
{"title":"A simplified control method for multivariable stable nonsquare systems with multiple time delays","authors":"C. Pop, R. D. De Keyser, C. Ionescu","doi":"10.1109/MED.2011.5983051","DOIUrl":"https://doi.org/10.1109/MED.2011.5983051","url":null,"abstract":"Time delays in multivariable nonsquare systems challenge the control action, firstly by limiting the degree of freedom and secondly because of the interaction that exists between various input-output channels. Different decoupling techniques associated with multivariable Smith Predictors have been proposed for the control of such plants. The design of the primary controller has also been intensively studied. The method proposed in this paper is a straightforward alternative to previously designed control structures for multivariable stable nonsquare time delay processes. The authors show that in this way the task of designing the controller is much simplified, while the overall performance of the closed loop system remains the same. Further, the control design is suitable for a general class of stable multivariable processes, rather than the limited applicability of the original method to processes that can be described by first order time delay transfer functions. Setpoint tracking, disturbance rejection and robustness tests are presented in comparison with the original method to prove the efficiency of the proposed simplified method.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128079351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983079
Natália M. R. Santos, Vítor M. Pires, R. Castro, J. Fernando Silva
The ability to control power flows in electric power systems is one of the crucial factors affecting the overall development of modern power systems. Among FACTS devices, the Unified Power Flow Controller (UPFC) is one the most efficient controller, offering a unique combination of shunt and series fast compensation. This device can be used to control both the active and reactive power of a transmission line. In this paper, a new methodology for incorporating the UPFC in a classical power system transient stability model is proposed. Due to UPFC model simplicity, the study of the dynamic behavior of a power system with embedded power electronics is made easier. A case-study is presented in order to show the effectiveness of the proposed approach. As a by-product, the contribution to enhance power system operation provided by UPFC devices is highlighted.
{"title":"Incorporating a Unified Power Flow Controller in a conventional transient stability model","authors":"Natália M. R. Santos, Vítor M. Pires, R. Castro, J. Fernando Silva","doi":"10.1109/MED.2011.5983079","DOIUrl":"https://doi.org/10.1109/MED.2011.5983079","url":null,"abstract":"The ability to control power flows in electric power systems is one of the crucial factors affecting the overall development of modern power systems. Among FACTS devices, the Unified Power Flow Controller (UPFC) is one the most efficient controller, offering a unique combination of shunt and series fast compensation. This device can be used to control both the active and reactive power of a transmission line. In this paper, a new methodology for incorporating the UPFC in a classical power system transient stability model is proposed. Due to UPFC model simplicity, the study of the dynamic behavior of a power system with embedded power electronics is made easier. A case-study is presented in order to show the effectiveness of the proposed approach. As a by-product, the contribution to enhance power system operation provided by UPFC devices is highlighted.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132686645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983200
Nicole Paces, A. Voigt, S. Jakubek, A. Schirrer, M. Kozek
This work presents a combined combustion load and combustion position control for a moving grate biomass furnace. The control design is based on a linearized reduced order model of the process and comprises model predictive control (MPC) with an additional proportional-integral (PI) feedback loop. An analysis for closed-loop stability as well as simulation results are presented. The results demonstrate the effectiveness of the proposed concept.
{"title":"Combined control of combustion load and combustion position in a moving grate biomass furnace","authors":"Nicole Paces, A. Voigt, S. Jakubek, A. Schirrer, M. Kozek","doi":"10.1109/MED.2011.5983200","DOIUrl":"https://doi.org/10.1109/MED.2011.5983200","url":null,"abstract":"This work presents a combined combustion load and combustion position control for a moving grate biomass furnace. The control design is based on a linearized reduced order model of the process and comprises model predictive control (MPC) with an additional proportional-integral (PI) feedback loop. An analysis for closed-loop stability as well as simulation results are presented. The results demonstrate the effectiveness of the proposed concept.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133271913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983101
K. Tahboub
PID control is presented in undergraduate control textbooks as a universal control method while often neglecting their limitations regarding unstable processes. A major limitation is due to the introduction of a close-to-the-origin zero that undermines the damping and causes excessive overshoot. This paper illustrates the problem through examples and proposes a simple alternative configuration where the PD part is placed in parallel to the process (inner loop) while the I part is left in cascade (outer loop). It is shown that this I-PD configuration stabilizes the process and achieves desired transient response without introducing unwanted zeros. Results from tracking and disturbance rejection control for MIMO systems in state space are used to prove that I-PD control guaranties full controllability, robustness, and asymptotic tracking and disturbance rejection for second-order processes whether they are stable, integral, or unstable.
{"title":"Suitability of PID controllers for unstable processes: An issue to be tackled in undergraduate control education","authors":"K. Tahboub","doi":"10.1109/MED.2011.5983101","DOIUrl":"https://doi.org/10.1109/MED.2011.5983101","url":null,"abstract":"PID control is presented in undergraduate control textbooks as a universal control method while often neglecting their limitations regarding unstable processes. A major limitation is due to the introduction of a close-to-the-origin zero that undermines the damping and causes excessive overshoot. This paper illustrates the problem through examples and proposes a simple alternative configuration where the PD part is placed in parallel to the process (inner loop) while the I part is left in cascade (outer loop). It is shown that this I-PD configuration stabilizes the process and achieves desired transient response without introducing unwanted zeros. Results from tracking and disturbance rejection control for MIMO systems in state space are used to prove that I-PD control guaranties full controllability, robustness, and asymptotic tracking and disturbance rejection for second-order processes whether they are stable, integral, or unstable.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133605278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983074
F. Vasca, R. Iervolino, L. Iannelli
We consider the stability problem of Lur'e systems composed by a dynamical linear time invariant system closed in feedback through a static mapping belonging to a region bounded by piecewise linear characteristics. By exploiting the complementarity framework a model of the region expressed through constrained relations is obtained. Classical conic sectors representations can be derived as a particular case of the proposed model. The region representation is exploited to prove absolute stability of the Lur'e system in terms of cone-constrained linear matrix inequalities.
{"title":"Stability of Lur'e systems with piecewise linear sector bounds","authors":"F. Vasca, R. Iervolino, L. Iannelli","doi":"10.1109/MED.2011.5983074","DOIUrl":"https://doi.org/10.1109/MED.2011.5983074","url":null,"abstract":"We consider the stability problem of Lur'e systems composed by a dynamical linear time invariant system closed in feedback through a static mapping belonging to a region bounded by piecewise linear characteristics. By exploiting the complementarity framework a model of the region expressed through constrained relations is obtained. Classical conic sectors representations can be derived as a particular case of the proposed model. The region representation is exploited to prove absolute stability of the Lur'e system in terms of cone-constrained linear matrix inequalities.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134309477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983175
G. Giannakis, G. Kontes, E. Kosmatopoulos, D. Rovas
Building Energy Management Systems are finding widespread use for the holistic control of all energy-influencing elements of buildings and are responsible for ensuring an effective and parsimonious energy use. In most cases, fixed-logic controllers are deployed in the building to implement predetermined strategies. Good performance can not be guaranteed due to inherent uncertainties that can not be a priori ascertained, such as weather variations, occupant actions, and changes in the building state and characteristics. In this paper, a model-assisted tuning methodology is presented to adaptively and automatically fine-tune relevant controller parameters. In our approach, at the end of each day of the building operation, given “reasonable” predictions for the following day, and using an accurate thermal-simulation model to evaluate performance, a new set of controller parameters is generated to be used the following day. This way, good performance can be achieved using controllers with simple mathematical structure.
{"title":"A model-assisted adaptive controller fine-tuning methodology for efficient energy use in buildings","authors":"G. Giannakis, G. Kontes, E. Kosmatopoulos, D. Rovas","doi":"10.1109/MED.2011.5983175","DOIUrl":"https://doi.org/10.1109/MED.2011.5983175","url":null,"abstract":"Building Energy Management Systems are finding widespread use for the holistic control of all energy-influencing elements of buildings and are responsible for ensuring an effective and parsimonious energy use. In most cases, fixed-logic controllers are deployed in the building to implement predetermined strategies. Good performance can not be guaranteed due to inherent uncertainties that can not be a priori ascertained, such as weather variations, occupant actions, and changes in the building state and characteristics. In this paper, a model-assisted tuning methodology is presented to adaptively and automatically fine-tune relevant controller parameters. In our approach, at the end of each day of the building operation, given “reasonable” predictions for the following day, and using an accurate thermal-simulation model to evaluate performance, a new set of controller parameters is generated to be used the following day. This way, good performance can be achieved using controllers with simple mathematical structure.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"123 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134311795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983151
R. Louali, Abdelmalek Belloula, M. Djouadi, S. Bouaziz
The purpose of this paper is to describe a real time characterization of FS2004 by measuring the dynamic model rate and quantify its temporal stability. This is done to evaluate Flight Simulator 2004 for a potential integration into HIL (Hardware In the Loop architecture) architecture used in developing embedded systems on UAVs. After a general presentation of the simulator and the reasons which lead us to study it, we describe the experimental procedure based on the definition of real-time simulation and Monte Carlo Method. Experiments conducted in different configurations allowed to isolate parameters that have a decisive impact on the real-time performances of the simulator.
{"title":"Real-time characterization of Microsoft Flight Simulator 2004 for integration into Hardware In the Loop architecture","authors":"R. Louali, Abdelmalek Belloula, M. Djouadi, S. Bouaziz","doi":"10.1109/MED.2011.5983151","DOIUrl":"https://doi.org/10.1109/MED.2011.5983151","url":null,"abstract":"The purpose of this paper is to describe a real time characterization of FS2004 by measuring the dynamic model rate and quantify its temporal stability. This is done to evaluate Flight Simulator 2004 for a potential integration into HIL (Hardware In the Loop architecture) architecture used in developing embedded systems on UAVs. After a general presentation of the simulator and the reasons which lead us to study it, we describe the experimental procedure based on the definition of real-time simulation and Monte Carlo Method. Experiments conducted in different configurations allowed to isolate parameters that have a decisive impact on the real-time performances of the simulator.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114303509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}