David Zumoffen | Universidad Tecnológica Nacional - FRRO (original) (raw)
Papers by David Zumoffen
Chemometrics and Intelligent Laboratory Systems, 2014
The kernel partial least squares (KPLS) method was originally focused on soft-sensor calibration ... more The kernel partial least squares (KPLS) method was originally focused on soft-sensor calibration for predicting online quality attributes. In this work, an analysis of the KPLS-based modeling technique and its application to non-linear process monitoring are presented. To this effect, the measurement decomposition, the development of new specific statistics acting on non-overlapped domains, and the contribution analysis are addressed for purposes of fault detection, diagnosis, and prediction risk assessment. Some practical insights for synthesizing the models are also given, which are related to an appropriate order selection and the adoption of the kernel function parameter. A proper combination of scaled statistics allows the definition of an efficient detection index for monitoring a non-linear process. The effectiveness of the proposed methods is confirmed by using simulation examples.
Renewable Energy, 2015
ABSTRACT
Noninvasive blood glucose sensors are still under development stage considering that they are far... more Noninvasive blood glucose sensors are still under development stage considering that they are far from being suitable for use in anartificial pancreas. The latter has three main parts: the blood glucose sensor, the insulin pump and the controller. However, for the biosensor analyzed here, some common failures such as signal shifts and unreal picks were found. They must be taken into account, for computing the correct insulin dosage for diabetic persons. Hence, a fault detection system based on discrete wavelets transform (DWT) is applied here. The main idea is, when the fault occurs, to do a proper measurement compensation for sending the corrected value to the predictive functional controller (PFC) algorithm. The study is done by reproducing the fault on the blood glucose measurements. They are obtained from a mathematical model of the endocrine system of an adult diabetic patient. This model was approved by the FDA in 2008. Then, the simulation environment includes faulty blood glucose measurements and a fault diagnosis and identification (FDI) system based on DWT. The FDI system gives to the PFC algorithm the correct information to turn it into a fault-tolerant controller (FTC). The main goal is to deliver the correct insulin dosage to the patient. Journal of Sensors 9 tolerant. The proofs done with the PFC show the potentiality of the overall methodology.
ABSTRACT This chapter presents two advanced control strategies based on model predictive control ... more ABSTRACT This chapter presents two advanced control strategies based on model predictive control to control the oxygen level in the cathode of a proton exchange membrane (PEM) fuel cell system. The objectives are to achieve a better efficiency and to maintain the necessary level of the oxygen in the cathode to prevent short circuit and membrane damage. First, a methodology of control based on dynamic matrix control (DMC) is proposed. This strategy includes a stationary and dynamic study of the advantages of using a regulating valve for the cathode outlet flow in combination with the compressor motor voltage as manipulated variables in a PEM fuel cell system. The influence of this input variable is exploited by implementing a predictive control strategy based on DMC, using these manipulated variables. The objectives of this control strategy are to regulate both the fuel cell voltage and oxygen excess ratio in the cathode, and thus, to improve the system performance. Second, a methodology of control based on adaptive predictive control with robust filter (APCWRF) is proposed. The APCWRF is designed for controlling the compressor motor voltage. Because of the wide working range the algorithm is improved with three different zones supported by three nominal linear models.
Computer Aided Chemical Engineering, 2005
This work describes the implementation of a Predictive Functional Control (PFC) algorithm on a te... more This work describes the implementation of a Predictive Functional Control (PFC) algorithm on a ternary batch distillation column to control temperature by manipulating the reflux ratio. The PFC is tuned off-line by using simplified models obtained by applying identification techniques. The temperature set point is described by a polynomial related with an optimal dynamic behaviour determined to achieve the composition specifications. The separation performance is closely checked with the help of a soft sensor, based on a non linear Hammerstein model described in a previous work, which input is top temperature and the outputs are the estimated compositions. Additionally the model composition estimations are employed for calculating the accumulated compositions for each tank. Therefore a type of split range control for the corresponding valves of each tank is programmed in order to storage each component under quality requirement. Experiments were performed on a rigorous model developed in HYSYS.Plant ® with data of a real pilot column. All concerning to control policy was implemented in MATLAB. Results comparing optimal PID and PFC are presented.
Green Energy and Technology, 2011
ABSTRACT In this chapter an approach based on fault detectability study for deciding the optimal ... more ABSTRACT In this chapter an approach based on fault detectability study for deciding the optimal measurements selection to build the principal component analysis model using combined statistics is addressed. It is believed that it will improve the monitoring systems design. The methodology applied here to the bioethanol processor with PEMFC is integrated to the previous stage of optimal sensor network and control structure selection detailed in Chap.12. The problem dimensionality could be important so genetic algorithms for stochastic global search is preferred to solve it. The solution can be driven properly to avoid the inclusion of sensors other than those installed for control purposes. It can be done through a good definition of the functional cost. The capacity of this methodology is demonstrated with a set of typical critical faults that could occur to this complex process.
Green Energy and Technology, 2011
ABSTRACT
Iberoamerican Journal of Industrial Engineering, 2011
In this work a systematic design procedure of a plant-wide control structure is applied to a well... more In this work a systematic design procedure of a plant-wide control structure is applied to a well known benchmark problem of a large-scale pulp mill process (CASTRO; DOYLE, 2004a). Because of the high dimension of this system it was necessary to develop some additional computer aided tools for support calculations. It is based on the minimization of the sum of squared deviations (SSD index) (ZUMOFFEN; BASUALDO, 2010) which is done via the use of genetic algorithm. It represents a good trade-off between achieve acceptable results with less computational effort. Previous works presented alternative solutions but using several heuristic considerations for reducing the problem dimensionality. The obtained performance with the selected control structure and the decentralized strategy, presented previously by , are compared. Several closed-loop simulations for critical set point changes are rigorously evaluated here.
Computer Aided Chemical Engineering, 2012
An artificial pancreas to solve the problem of type I diabetes mellitus is a closed loop system c... more An artificial pancreas to solve the problem of type I diabetes mellitus is a closed loop system composed of a blood glucose biosensor, a control algorithm and an insulin pump. It is in charge of maintaining plasma glucose concentration of a diabetic patient within the healthy range of 70 -180 mg/dl. In this paper, an improved adaptive predictive control with robust filter (APCWRF) is tested as a new control algorithm to be applied for this purpose. Some modifications such as the shape of the glycaemia reference trajectory, based on the plasma glucose evolution of a healthy person having the same meal intake, is introduced. In addition, a variable weighting factor (α i ) in the cost function is included in order to prevent dangerous glycaemia incursions close to the allowed limits. Meal announcement in advance is combined with feedback control to improve the glycaemia regulation. Finally, this control algorithm is rigorously tested on a recognized simulator of type I diabetic patients that has been approved in 2008 by the FDA.
Computer Aided Chemical Engineering, 2012
Proceedings of the 45th IEEE Conference on Decision and Control, 2006
In this paper, a new fault-tolerant control (FTC) strategy is proposed to compensate for the effe... more In this paper, a new fault-tolerant control (FTC) strategy is proposed to compensate for the effects of faults and to improve the overall performance for nonlinear stable plants. The FTC approach involves a commutation of a linear time-varying robust filter in the feedback path of the control loop in synchronization with an adaptive predictive controller. The decision of which mode
A model predictive control (MPC) scheme integrated with a recently developed fault detection, iso... more A model predictive control (MPC) scheme integrated with a recently developed fault detection, isolation, and estimation (FDIE) system applied on a pulp mill (PM) process is discussed. This work belongs to a series whose objective is to achieve improvements on ...
2010 IEEE Vehicle Power and Propulsion Conference, 2010
The transient behavior of a Polymer Electrolyte Membrane Fuel Cell System (PEMFCS) under an effic... more The transient behavior of a Polymer Electrolyte Membrane Fuel Cell System (PEMFCS) under an efficient Adaptive Predictive Control with Robust Filter (APCWRF) is analyzed. This control scheme is tested to evaluate its performance when sudden changes in the load occur. It is produced by the demands of the electric motor of a hybrid vehicle, powered by a PEMFC and a supercapacitor bank to fulfil Standard Driving Cycles. The objective of the proposed advanced strategy is to control the oxygen excess ratio in the cathode to improve the system efficiency and to ensure a safe operation for the PEM. Several results through a simulation environment are presented. They are useful for showing the potentiality of the APCWRF for the proposed exigent scenarios .
In this work a new methodology for solving simultaneously the problems of optimal sensor location... more In this work a new methodology for solving simultaneously the problems of optimal sensor location and control structure selection for large scale chemical processes is presented. Here, it is considered the need of guaranteing the best plant-wide control structure before answering about which is the best sensor net able for achieving that objective. In this work it is demonstrated the importance of answer both questions as an integrated problem because of the strong impact in the initial investment and the future controlled process performance. Most of the previous works in this area analyze these problems as separated subjects. Here, genetic algorithms (GA) are used because they represent a valuable tool for support the decisions about the sensor placement, possible pairing of input output variables among a great number of combinations, since the interaction effect point of view. It allows to avoid the expert knowledge as decision criteria for pairing selection. The preliminary study is done on a simplified plant model obtained by subspace identification techniques (4sid). The final testing is performed on the rigorous dynamic model with the obtained plant-wide structure where the controllers tuning is performed through the internal model control (IMC) theory. The well-known case of the Tennessee Eastman (TE) benchmark is adopted for testing the methodology described here and compared with other strategies.
A new systematic approach for addressing the problem of the plant-wide control structure, support... more A new systematic approach for addressing the problem of the plant-wide control structure, supported by steady-state information is presented. It is tested in a reactor/separator with recycle plant. Several authors have presented different control alternatives for this kind of plant. However, most of them mainly focused on the optimum energy consumption or in the regulator problem only. In both cases
Industrial & Engineering Chemistry Research, 2008
A model predictive control (MPC) scheme integrated with a recently developed fault detection, iso... more A model predictive control (MPC) scheme integrated with a recently developed fault detection, isolation, and estimation (FDIE) system applied on a pulp mill (PM) process is discussed. This work belongs to a series whose objective is to achieve improvements on ...
International Journal of Hydrogen Energy, 2013
International Journal of Hydrogen Energy, 2012
ABSTRACT The main contribution of this work is the application of a novel technique for the plant... more ABSTRACT The main contribution of this work is the application of a novel technique for the plant-wide control design to a challenging bio-ethanol processor system for hydrogen production. It is based on steam reforming, followed by high and low-temperature shift reactors and preferential oxidation. The obtained hydrogen feeds a fuel cell for automotive use. The control structure is defined by using a well-tested, systematic and generalized procedure, named minimum square deviation. It allows keeping the process at the operating point of maximum efficiency. This design procedure accounts both, set point as well as disturbances effects which can be sorted according to their importance through specific weighting matrices. The first step of this approach solves the problem of obtaining the best-controlled variables. Then, the search involves testing several combinations between the available input–output variables. The overall processor system with fuel cell, able for doing the tests, was modeled by using mass and energy balances, chemical equilibrium, thermodynamic models and feasible heat transfer conditions. The selected control structure is rigorously tested applied in the dynamic model of the complete plant. The computational implementation of this model was made by using a suitable integration of three well-known programs: MATLAB, HYSYS and ADVISOR. The simulations are performed for hybrid vehicle (PEMFC and supercapacitors). The disturbance profile corresponds to a urban standard driving cycle, which is one of the most exigent. The conclusions are based on fuel consumptions, typical performance indexes used for control strategy evaluations and a trade-off between cost investments and efficiency.
International Journal of Hydrogen Energy, 2014
Bioethanol System sizing Energy management strategy PEM fuel cells Stand alone power systems a b ... more Bioethanol System sizing Energy management strategy PEM fuel cells Stand alone power systems a b s t r a c t
Chemometrics and Intelligent Laboratory Systems, 2014
The kernel partial least squares (KPLS) method was originally focused on soft-sensor calibration ... more The kernel partial least squares (KPLS) method was originally focused on soft-sensor calibration for predicting online quality attributes. In this work, an analysis of the KPLS-based modeling technique and its application to non-linear process monitoring are presented. To this effect, the measurement decomposition, the development of new specific statistics acting on non-overlapped domains, and the contribution analysis are addressed for purposes of fault detection, diagnosis, and prediction risk assessment. Some practical insights for synthesizing the models are also given, which are related to an appropriate order selection and the adoption of the kernel function parameter. A proper combination of scaled statistics allows the definition of an efficient detection index for monitoring a non-linear process. The effectiveness of the proposed methods is confirmed by using simulation examples.
Renewable Energy, 2015
ABSTRACT
Noninvasive blood glucose sensors are still under development stage considering that they are far... more Noninvasive blood glucose sensors are still under development stage considering that they are far from being suitable for use in anartificial pancreas. The latter has three main parts: the blood glucose sensor, the insulin pump and the controller. However, for the biosensor analyzed here, some common failures such as signal shifts and unreal picks were found. They must be taken into account, for computing the correct insulin dosage for diabetic persons. Hence, a fault detection system based on discrete wavelets transform (DWT) is applied here. The main idea is, when the fault occurs, to do a proper measurement compensation for sending the corrected value to the predictive functional controller (PFC) algorithm. The study is done by reproducing the fault on the blood glucose measurements. They are obtained from a mathematical model of the endocrine system of an adult diabetic patient. This model was approved by the FDA in 2008. Then, the simulation environment includes faulty blood glucose measurements and a fault diagnosis and identification (FDI) system based on DWT. The FDI system gives to the PFC algorithm the correct information to turn it into a fault-tolerant controller (FTC). The main goal is to deliver the correct insulin dosage to the patient. Journal of Sensors 9 tolerant. The proofs done with the PFC show the potentiality of the overall methodology.
ABSTRACT This chapter presents two advanced control strategies based on model predictive control ... more ABSTRACT This chapter presents two advanced control strategies based on model predictive control to control the oxygen level in the cathode of a proton exchange membrane (PEM) fuel cell system. The objectives are to achieve a better efficiency and to maintain the necessary level of the oxygen in the cathode to prevent short circuit and membrane damage. First, a methodology of control based on dynamic matrix control (DMC) is proposed. This strategy includes a stationary and dynamic study of the advantages of using a regulating valve for the cathode outlet flow in combination with the compressor motor voltage as manipulated variables in a PEM fuel cell system. The influence of this input variable is exploited by implementing a predictive control strategy based on DMC, using these manipulated variables. The objectives of this control strategy are to regulate both the fuel cell voltage and oxygen excess ratio in the cathode, and thus, to improve the system performance. Second, a methodology of control based on adaptive predictive control with robust filter (APCWRF) is proposed. The APCWRF is designed for controlling the compressor motor voltage. Because of the wide working range the algorithm is improved with three different zones supported by three nominal linear models.
Computer Aided Chemical Engineering, 2005
This work describes the implementation of a Predictive Functional Control (PFC) algorithm on a te... more This work describes the implementation of a Predictive Functional Control (PFC) algorithm on a ternary batch distillation column to control temperature by manipulating the reflux ratio. The PFC is tuned off-line by using simplified models obtained by applying identification techniques. The temperature set point is described by a polynomial related with an optimal dynamic behaviour determined to achieve the composition specifications. The separation performance is closely checked with the help of a soft sensor, based on a non linear Hammerstein model described in a previous work, which input is top temperature and the outputs are the estimated compositions. Additionally the model composition estimations are employed for calculating the accumulated compositions for each tank. Therefore a type of split range control for the corresponding valves of each tank is programmed in order to storage each component under quality requirement. Experiments were performed on a rigorous model developed in HYSYS.Plant ® with data of a real pilot column. All concerning to control policy was implemented in MATLAB. Results comparing optimal PID and PFC are presented.
Green Energy and Technology, 2011
ABSTRACT In this chapter an approach based on fault detectability study for deciding the optimal ... more ABSTRACT In this chapter an approach based on fault detectability study for deciding the optimal measurements selection to build the principal component analysis model using combined statistics is addressed. It is believed that it will improve the monitoring systems design. The methodology applied here to the bioethanol processor with PEMFC is integrated to the previous stage of optimal sensor network and control structure selection detailed in Chap.12. The problem dimensionality could be important so genetic algorithms for stochastic global search is preferred to solve it. The solution can be driven properly to avoid the inclusion of sensors other than those installed for control purposes. It can be done through a good definition of the functional cost. The capacity of this methodology is demonstrated with a set of typical critical faults that could occur to this complex process.
Green Energy and Technology, 2011
ABSTRACT
Iberoamerican Journal of Industrial Engineering, 2011
In this work a systematic design procedure of a plant-wide control structure is applied to a well... more In this work a systematic design procedure of a plant-wide control structure is applied to a well known benchmark problem of a large-scale pulp mill process (CASTRO; DOYLE, 2004a). Because of the high dimension of this system it was necessary to develop some additional computer aided tools for support calculations. It is based on the minimization of the sum of squared deviations (SSD index) (ZUMOFFEN; BASUALDO, 2010) which is done via the use of genetic algorithm. It represents a good trade-off between achieve acceptable results with less computational effort. Previous works presented alternative solutions but using several heuristic considerations for reducing the problem dimensionality. The obtained performance with the selected control structure and the decentralized strategy, presented previously by , are compared. Several closed-loop simulations for critical set point changes are rigorously evaluated here.
Computer Aided Chemical Engineering, 2012
An artificial pancreas to solve the problem of type I diabetes mellitus is a closed loop system c... more An artificial pancreas to solve the problem of type I diabetes mellitus is a closed loop system composed of a blood glucose biosensor, a control algorithm and an insulin pump. It is in charge of maintaining plasma glucose concentration of a diabetic patient within the healthy range of 70 -180 mg/dl. In this paper, an improved adaptive predictive control with robust filter (APCWRF) is tested as a new control algorithm to be applied for this purpose. Some modifications such as the shape of the glycaemia reference trajectory, based on the plasma glucose evolution of a healthy person having the same meal intake, is introduced. In addition, a variable weighting factor (α i ) in the cost function is included in order to prevent dangerous glycaemia incursions close to the allowed limits. Meal announcement in advance is combined with feedback control to improve the glycaemia regulation. Finally, this control algorithm is rigorously tested on a recognized simulator of type I diabetic patients that has been approved in 2008 by the FDA.
Computer Aided Chemical Engineering, 2012
Proceedings of the 45th IEEE Conference on Decision and Control, 2006
In this paper, a new fault-tolerant control (FTC) strategy is proposed to compensate for the effe... more In this paper, a new fault-tolerant control (FTC) strategy is proposed to compensate for the effects of faults and to improve the overall performance for nonlinear stable plants. The FTC approach involves a commutation of a linear time-varying robust filter in the feedback path of the control loop in synchronization with an adaptive predictive controller. The decision of which mode
A model predictive control (MPC) scheme integrated with a recently developed fault detection, iso... more A model predictive control (MPC) scheme integrated with a recently developed fault detection, isolation, and estimation (FDIE) system applied on a pulp mill (PM) process is discussed. This work belongs to a series whose objective is to achieve improvements on ...
2010 IEEE Vehicle Power and Propulsion Conference, 2010
The transient behavior of a Polymer Electrolyte Membrane Fuel Cell System (PEMFCS) under an effic... more The transient behavior of a Polymer Electrolyte Membrane Fuel Cell System (PEMFCS) under an efficient Adaptive Predictive Control with Robust Filter (APCWRF) is analyzed. This control scheme is tested to evaluate its performance when sudden changes in the load occur. It is produced by the demands of the electric motor of a hybrid vehicle, powered by a PEMFC and a supercapacitor bank to fulfil Standard Driving Cycles. The objective of the proposed advanced strategy is to control the oxygen excess ratio in the cathode to improve the system efficiency and to ensure a safe operation for the PEM. Several results through a simulation environment are presented. They are useful for showing the potentiality of the APCWRF for the proposed exigent scenarios .
In this work a new methodology for solving simultaneously the problems of optimal sensor location... more In this work a new methodology for solving simultaneously the problems of optimal sensor location and control structure selection for large scale chemical processes is presented. Here, it is considered the need of guaranteing the best plant-wide control structure before answering about which is the best sensor net able for achieving that objective. In this work it is demonstrated the importance of answer both questions as an integrated problem because of the strong impact in the initial investment and the future controlled process performance. Most of the previous works in this area analyze these problems as separated subjects. Here, genetic algorithms (GA) are used because they represent a valuable tool for support the decisions about the sensor placement, possible pairing of input output variables among a great number of combinations, since the interaction effect point of view. It allows to avoid the expert knowledge as decision criteria for pairing selection. The preliminary study is done on a simplified plant model obtained by subspace identification techniques (4sid). The final testing is performed on the rigorous dynamic model with the obtained plant-wide structure where the controllers tuning is performed through the internal model control (IMC) theory. The well-known case of the Tennessee Eastman (TE) benchmark is adopted for testing the methodology described here and compared with other strategies.
A new systematic approach for addressing the problem of the plant-wide control structure, support... more A new systematic approach for addressing the problem of the plant-wide control structure, supported by steady-state information is presented. It is tested in a reactor/separator with recycle plant. Several authors have presented different control alternatives for this kind of plant. However, most of them mainly focused on the optimum energy consumption or in the regulator problem only. In both cases
Industrial & Engineering Chemistry Research, 2008
A model predictive control (MPC) scheme integrated with a recently developed fault detection, iso... more A model predictive control (MPC) scheme integrated with a recently developed fault detection, isolation, and estimation (FDIE) system applied on a pulp mill (PM) process is discussed. This work belongs to a series whose objective is to achieve improvements on ...
International Journal of Hydrogen Energy, 2013
International Journal of Hydrogen Energy, 2012
ABSTRACT The main contribution of this work is the application of a novel technique for the plant... more ABSTRACT The main contribution of this work is the application of a novel technique for the plant-wide control design to a challenging bio-ethanol processor system for hydrogen production. It is based on steam reforming, followed by high and low-temperature shift reactors and preferential oxidation. The obtained hydrogen feeds a fuel cell for automotive use. The control structure is defined by using a well-tested, systematic and generalized procedure, named minimum square deviation. It allows keeping the process at the operating point of maximum efficiency. This design procedure accounts both, set point as well as disturbances effects which can be sorted according to their importance through specific weighting matrices. The first step of this approach solves the problem of obtaining the best-controlled variables. Then, the search involves testing several combinations between the available input–output variables. The overall processor system with fuel cell, able for doing the tests, was modeled by using mass and energy balances, chemical equilibrium, thermodynamic models and feasible heat transfer conditions. The selected control structure is rigorously tested applied in the dynamic model of the complete plant. The computational implementation of this model was made by using a suitable integration of three well-known programs: MATLAB, HYSYS and ADVISOR. The simulations are performed for hybrid vehicle (PEMFC and supercapacitors). The disturbance profile corresponds to a urban standard driving cycle, which is one of the most exigent. The conclusions are based on fuel consumptions, typical performance indexes used for control strategy evaluations and a trade-off between cost investments and efficiency.
International Journal of Hydrogen Energy, 2014
Bioethanol System sizing Energy management strategy PEM fuel cells Stand alone power systems a b ... more Bioethanol System sizing Energy management strategy PEM fuel cells Stand alone power systems a b s t r a c t