Reports de recerca
http://hdl.handle.net/2117/1127
2016-06-01T02:41:39ZTemperature modelling and model predictive control of a pilot-scale batch reaction system
http://hdl.handle.net/2117/77066
Temperature modelling and model predictive control of a pilot-scale batch reaction system
Sánchez Cossio, Javier; Ocampo-Martínez, Carlos
The temperature control equipment on a pilot scale batch reaction system located at EAFIT University in Medelln, Colombia, is modeled and a new controller is designed aiming at using it in the reactor current PLC-based control system. Some mathematical models are developed from experimental data to describe the system behavior and using them several model based predictive controllers are designed. The simplest, yet reliable, model obtained is an ARX polynomial model of order (1,1,1) that yields a four states ane model for which an explicit MPC was calculated.
This controller has a reduced mathematical complexity and can probably be used directly on the existing control system.
2015-09-23T16:46:56ZSánchez Cossio, JavierOcampo-Martínez, CarlosThe temperature control equipment on a pilot scale batch reaction system located at EAFIT University in Medelln, Colombia, is modeled and a new controller is designed aiming at using it in the reactor current PLC-based control system. Some mathematical models are developed from experimental data to describe the system behavior and using them several model based predictive controllers are designed. The simplest, yet reliable, model obtained is an ARX polynomial model of order (1,1,1) that yields a four states ane model for which an explicit MPC was calculated.
This controller has a reduced mathematical complexity and can probably be used directly on the existing control system.Nonlinear model of leachate anaerobic digestion treatment process
http://hdl.handle.net/2117/27973
Nonlinear model of leachate anaerobic digestion treatment process
Alzate Ibáñez, Angélica María; Ocampo-Martínez, Carlos
In this report a continuous adaptive high-gain observer method is presented for the estimation of state variables that could not be measurable online and unknown time-varying parameters of leachate anaerobic digestion treatment process. The high-gain observer is a variant of the Luenberger extended observer and involves an adjustable gain parameter. It is characterized by easy implementation and calibration, is stable and exhibit exponential convergence. The observer is based on a simplified mathematical model of the system. Calibration of the model was performed with real data from the Upflow Anaerobic Sludge Blanket (UASB) reactor for landfill leachate treatment in open loop under normal operational conditions. The model performance is evaluated via numerical simulations showing adequate results. The criteria used for considering the model as acceptable is to calculate the values of Mean Magnitude of Relative Error (MMRE) and Prediction at level l.
2015-05-19T18:14:16ZAlzate Ibáñez, Angélica MaríaOcampo-Martínez, CarlosIn this report a continuous adaptive high-gain observer method is presented for the estimation of state variables that could not be measurable online and unknown time-varying parameters of leachate anaerobic digestion treatment process. The high-gain observer is a variant of the Luenberger extended observer and involves an adjustable gain parameter. It is characterized by easy implementation and calibration, is stable and exhibit exponential convergence. The observer is based on a simplified mathematical model of the system. Calibration of the model was performed with real data from the Upflow Anaerobic Sludge Blanket (UASB) reactor for landfill leachate treatment in open loop under normal operational conditions. The model performance is evaluated via numerical simulations showing adequate results. The criteria used for considering the model as acceptable is to calculate the values of Mean Magnitude of Relative Error (MMRE) and Prediction at level l.Hybrid linear sewer network model
http://hdl.handle.net/2117/22803
Hybrid linear sewer network model
Joseph Duran, Bernat; Ocampo-Martínez, Carlos; Cembrano Gennari, Gabriela
This technical report presents a novel control-oriented hybrid linear sewer network model. It also provides the mathematical details of the Mixed Logical Dynamic (MLD) systems reformulation of the system equations to turn all the involved hybrid/logical statements into linear inequalities by means of the definition of binary variables. Using this reformulation a compact hybrid linear delayed expression is obtained to be used for simulation or optimal control purposes.
2014-05-02T12:53:49ZJoseph Duran, BernatOcampo-Martínez, CarlosCembrano Gennari, GabrielaThis technical report presents a novel control-oriented hybrid linear sewer network model. It also provides the mathematical details of the Mixed Logical Dynamic (MLD) systems reformulation of the system equations to turn all the involved hybrid/logical statements into linear inequalities by means of the definition of binary variables. Using this reformulation a compact hybrid linear delayed expression is obtained to be used for simulation or optimal control purposes.Model and requirements for a multiresolution time series database management system
http://hdl.handle.net/2117/19183
Model and requirements for a multiresolution time series database management system
Llusa Serra, Aleix; Escobet Canal, Teresa; Vila Marta, Sebastià
In this paper we define a model for multiresolution time series database management systems. The main objective is to store compactly a time series and manage consistently its temporal dimension. It is achieved by extracting diferent resolutions and attributes summaries from the time series.
Our work is concerned in putting together two areas of study: time series analysis and database management systems (DBMS). Time series analysis offers a great deal of methodologies and algorithms to process time series data and database field provides software expertise in managing data. Therefore it is of primary relevance that DBMS support time series.
2013-05-13T15:19:06ZLlusa Serra, AleixEscobet Canal, TeresaVila Marta, SebastiàIn this paper we define a model for multiresolution time series database management systems. The main objective is to store compactly a time series and manage consistently its temporal dimension. It is achieved by extracting diferent resolutions and attributes summaries from the time series.
Our work is concerned in putting together two areas of study: time series analysis and database management systems (DBMS). Time series analysis offers a great deal of methodologies and algorithms to process time series data and database field provides software expertise in managing data. Therefore it is of primary relevance that DBMS support time series.Modelling and decentralized model predictive control of drinking water networks: the Barcelona case study
http://hdl.handle.net/2117/7175
Modelling and decentralized model predictive control of drinking water networks: the Barcelona case study
Fambrini, Valentina; Ocampo-Martínez, Carlos
In this report, MPC strategies have been designed and tested for the global centralized and decentralized control of drinking water networks. Test have been performed in order to highlight the advantages of having a partition of a complex network in several subsystems. Despite the possible suboptimal solution of the optimization problems from the global point of view, the clear gain related to the computation times and loads has been demonstrated by means of the simulations and test developed here. The high correlation between system elements, i.e., the strong coupling of the network, makes impossible to have independent subsystems to be controlled by using a set of decoupled MPC controllers. Moreover, the necessity of a hierarchy scheme is discussed and interesting results are obtained from the mixture of techniques giving rise to a control law sharing decentralized and hierarchical features.
2010-05-12T07:46:28ZFambrini, ValentinaOcampo-Martínez, CarlosIn this report, MPC strategies have been designed and tested for the global centralized and decentralized control of drinking water networks. Test have been performed in order to highlight the advantages of having a partition of a complex network in several subsystems. Despite the possible suboptimal solution of the optimization problems from the global point of view, the clear gain related to the computation times and loads has been demonstrated by means of the simulations and test developed here. The high correlation between system elements, i.e., the strong coupling of the network, makes impossible to have independent subsystems to be controlled by using a set of decoupled MPC controllers. Moreover, the necessity of a hierarchy scheme is discussed and interesting results are obtained from the mixture of techniques giving rise to a control law sharing decentralized and hierarchical features.Development of a Simulation Environment for Water Drinking Networks: Application to the Validation of a Centralized MPC Controller for the Barcelona Case Study
http://hdl.handle.net/2117/7101
Development of a Simulation Environment for Water Drinking Networks: Application to the Validation of a Centralized MPC Controller for the Barcelona Case Study
Caini, Elena; Puig Cayuela, Vicenç; Cembrano Gennari, Gabriela
In this report, MPC strategies have been designed and tested for the global centralized control of a drinking water network. Test have been implemented by using a software tool called PLIO, which allows the user to select the simulation parameters as well as the demands episodes in order to obtain the desired results. Additionally, this report describes the implementation of a MATLAB-based simulator of a plant model related to the Barcelona drinking water network. Several simulations and test have been done and conclusions from the obtained results are outlined and discussed.
2010-04-30T13:26:47ZCaini, ElenaPuig Cayuela, VicençCembrano Gennari, GabrielaIn this report, MPC strategies have been designed and tested for the global centralized control of a drinking water network. Test have been implemented by using a software tool called PLIO, which allows the user to select the simulation parameters as well as the demands episodes in order to obtain the desired results. Additionally, this report describes the implementation of a MATLAB-based simulator of a plant model related to the Barcelona drinking water network. Several simulations and test have been done and conclusions from the obtained results are outlined and discussed.Modelling approaches for predictive control of large-scale sewage systems
http://hdl.handle.net/2117/6505
Modelling approaches for predictive control of large-scale sewage systems
Ocampo-Martínez, Carlos; Puig Cayuela, Vicenç
In this report, model predictive control (MPC) of large-scale sewage systems is addressed considering different modelling approaches that include several inherent continuous/discrete phenomena
(overflows in sewers and tanks) and elements (weirs) in the system that result in distinct
behaviour depending on the dynamic state (
flow/volume) of the network. These behaviours
can not be neglected nor can be modelled by a pure linear representation. In order the MPC controller takes into account these phenomena and elements, a modelling approach based on piece-wise linear functions is proposed and compared against a hybrid modelling approach previously
reported by the authors. Control performance results and associated computation times
of the closed-loop scheme considering both modelling approaches are compared by using a real case study based on the Barcelona sewer network.
2010-03-01T09:16:36ZOcampo-Martínez, CarlosPuig Cayuela, VicençIn this report, model predictive control (MPC) of large-scale sewage systems is addressed considering different modelling approaches that include several inherent continuous/discrete phenomena
(overflows in sewers and tanks) and elements (weirs) in the system that result in distinct
behaviour depending on the dynamic state (
flow/volume) of the network. These behaviours
can not be neglected nor can be modelled by a pure linear representation. In order the MPC controller takes into account these phenomena and elements, a modelling approach based on piece-wise linear functions is proposed and compared against a hybrid modelling approach previously
reported by the authors. Control performance results and associated computation times
of the closed-loop scheme considering both modelling approaches are compared by using a real case study based on the Barcelona sewer network.Reducció de variables en problemes de control predictiu amb restriccions d'igualtat
http://hdl.handle.net/2117/6434
Reducció de variables en problemes de control predictiu amb restriccions d'igualtat
Joseph Duran, Bernat; Ocampo-Martínez, Carlos
En el següent document es mostra una técnica per utilitzar les restriccions d'igualtat associades a un problema de control predictiu per tal de reduir el nombre de variables que intervenen en aquest problema. Primerament fem un repàs de les notacions i desenvolupament del problema
estàndard per veure, després, que mitjançant un canvi lineal el nou problema, amb un nombre inferior de variables, té una estructura completament anàloga. Alguns resultats de temps de computació mostren, en la última secció, la utilitat del mètode.
2010-02-22T13:12:51ZJoseph Duran, BernatOcampo-Martínez, Carlos