The Experts below are selected from a list of 42 Experts worldwide ranked by ideXlab platform

Eduardo F. Camacho - One of the best experts on this subject based on the ideXlab platform.

  • Adaptive incremental state space MPC for collector defocusing of a parabolic Trough Plant
    Solar Energy, 2019
    Co-Authors: Adolfo J. Sanchez, Antonio J. Gallego, Juan Manuel Escaño, Eduardo F. Camacho
    Abstract:

    Abstract Commercial Solar Plants produce energy around a nominal operating point in which the Solar field outlet temperature is high and close to the thermal limit of the heat transfer fluid. The main control of the temperature is carried out by means of the fluid flow-rate that circulates through the Solar field. Defocusing the collectors is normally used as a safety mechanism to avoid exceeding the thermal limit. However, in situations in which the flow is saturated, the control of defocusing the collectors becomes of vital importance and is the system in charge of controlling the Solar field outlet temperature. The paper presents an Adaptive State Space Model Predictive Control strategy with an incremental formulation to control the fourth and third collector defocus angles for field outlet temperature set-point tracking at the nominal operation point, avoiding the Heat Transfer Fluid temperature from exceeding the manufacturer thermal limit (oil degradation). The state space description uses an Unscented Kalman Filter for estimating the non-measurable states. A 50 MW parabolic Solar Trough Plant nonlinear model has been used to design and validate the strategy. Simulation results are presented showing the advantages of using the proposed strategy.

  • Event-based MPC for defocusing and power production of a parabolic Trough Plant under power limitation
    Solar Energy, 2018
    Co-Authors: Adolfo J. Sanchez, Antonio J. Gallego, Juan Manuel Escaño, Eduardo F. Camacho
    Abstract:

    Abstract Optimal operation of a Solar Plant is generally understood as a tracking of the optimal working temperatures which maximize the net electric power. However, a commercial Solar Plant may receive a limitation from the Transmission System Operator due to saturation of the electrical grid. In these situations the Plant moves to an operation mode in which the objective is not maximum production but compliance with the orders of the Transmission System Operator. The paper proposes an Event-Based Gain Scheduling Generalized Predictive Control strategy for electric power production reference tracking when power limitations are imposed by the Transmission System Operator. Gain Scheduling Generalized Predictive Controllers are proposed to control fourth and third collector defocus in order to prevent heating fluid temperature from exceeding the limits of the manufacturer and therefore, avoid oil degradation. A 50 MW parabolic Solar Trough Plant model has been used to design and validate the strategy. Simulation results are presented showing the advantages of using the proposed strategy.

  • Temperature homogenization of a Solar Trough field for performance improvement
    Solar Energy, 2018
    Co-Authors: Adolfo J. Sanchez, Antonio J. Gallego, Juan Manuel Escaño, Eduardo F. Camacho
    Abstract:

    Abstract Optimal operation of Solar Plant is a challenge due to the multiple disturbances affecting the Plant. Research in optimal temperature set-point tracking is extensive whereas research concerning optimal power production under disturbances is not. A Solar Plant has to deal not only with temperature and radiation disturbances but also with dirt accumulated on the collectors which lead to a great disparity in collectors reflectivity. Cleaner collectors produce higher output temperature because of the higher reflectivity. In fact the temperature in this collector may be so high that they have to be defocused with the corresponding energy losses. The paradox is that the most efficient loops may be the one collecting less energy because of defocusing. This paper proposes a new solution based in the manipulation of the loops input valves in order to homogenize the temperatures of the different loops and avoid defocusing. The paper presents an original non linear model based optimization to homogenize the loop temperatures by manipulating the inlet valves of the loops. The nonlinear model is based on a distributed parameters model. In order to perform the optimization, temperature profiles of the loops and its reflectivities are needed. These are obtained by means of a Classification and Regression Trees (CARTs) trained with the full distributed parameters model. Simulations are carried out using a model of the Plataforma Solar de Almeria (PSA) Solar Trough Plant to show the results of the proposed control scheme, temperature homogenization and production benefit.

  • Fault tolerant MPC of a Solar Trough field based on classification and regression trees
    2016 3rd Conference on Control and Fault-Tolerant Systems (SysTol), 2016
    Co-Authors: Adolfo J. Sanchez, Juan M. Escaño, Antonio J. Gallego, Eduardo F. Camacho
    Abstract:

    Direct Solar radiation is important in a Solar Trough Plant because it is the perturbation that affects most the operation. Generally, it is measured locally. Production losses or dangerous situations may occur when controlling a Plant with wrong measurements. A possible solution is to have several pyrheliometers though two problems arise: cost and sensor fusion (complexity). The aim of this paper is to prove that a Solar estimation based on Classification and Regression Trees can be used to design a Fault Tolerant Model Predictive Control strategy capable to work with erroneous values of radiation or even none, avoiding dangerous situations or production losses.

  • Solar radiation estimator and fault tolerant model predictive control of a parabolic-Trough field
    2015 26th Irish Signals and Systems Conference (ISSC), 2015
    Co-Authors: Adolfo J. Sanchez, Juan M. Escaño, Niel Canty, Antonio J. Gallego, Eduardo F. Camacho
    Abstract:

    In this paper we propose an estimator of Solar radiation and a heuristic radiation selector to design a Solar radiation Fault Tolerant Model Predictive Control strategy for Solar Trough Plants. The complete design of the control system proposed has been simulated using the model of ACUREX Solar Trough Plant at the Plataforma Solar de Almería (PSA) using a Gain Scheduling Generalized Predictive Control(GS-GPC) control strategy. Simulation results (estimation/heuristic selector/GS-GPC) of the proposed scheme are compared with simulations of the same GS-GPC controller strategy when using only a pyrheliometer radiation measurement.

Antonio J. Gallego - One of the best experts on this subject based on the ideXlab platform.

  • Adaptive incremental state space MPC for collector defocusing of a parabolic Trough Plant
    Solar Energy, 2019
    Co-Authors: Adolfo J. Sanchez, Antonio J. Gallego, Juan Manuel Escaño, Eduardo F. Camacho
    Abstract:

    Abstract Commercial Solar Plants produce energy around a nominal operating point in which the Solar field outlet temperature is high and close to the thermal limit of the heat transfer fluid. The main control of the temperature is carried out by means of the fluid flow-rate that circulates through the Solar field. Defocusing the collectors is normally used as a safety mechanism to avoid exceeding the thermal limit. However, in situations in which the flow is saturated, the control of defocusing the collectors becomes of vital importance and is the system in charge of controlling the Solar field outlet temperature. The paper presents an Adaptive State Space Model Predictive Control strategy with an incremental formulation to control the fourth and third collector defocus angles for field outlet temperature set-point tracking at the nominal operation point, avoiding the Heat Transfer Fluid temperature from exceeding the manufacturer thermal limit (oil degradation). The state space description uses an Unscented Kalman Filter for estimating the non-measurable states. A 50 MW parabolic Solar Trough Plant nonlinear model has been used to design and validate the strategy. Simulation results are presented showing the advantages of using the proposed strategy.

  • Event-based MPC for defocusing and power production of a parabolic Trough Plant under power limitation
    Solar Energy, 2018
    Co-Authors: Adolfo J. Sanchez, Antonio J. Gallego, Juan Manuel Escaño, Eduardo F. Camacho
    Abstract:

    Abstract Optimal operation of a Solar Plant is generally understood as a tracking of the optimal working temperatures which maximize the net electric power. However, a commercial Solar Plant may receive a limitation from the Transmission System Operator due to saturation of the electrical grid. In these situations the Plant moves to an operation mode in which the objective is not maximum production but compliance with the orders of the Transmission System Operator. The paper proposes an Event-Based Gain Scheduling Generalized Predictive Control strategy for electric power production reference tracking when power limitations are imposed by the Transmission System Operator. Gain Scheduling Generalized Predictive Controllers are proposed to control fourth and third collector defocus in order to prevent heating fluid temperature from exceeding the limits of the manufacturer and therefore, avoid oil degradation. A 50 MW parabolic Solar Trough Plant model has been used to design and validate the strategy. Simulation results are presented showing the advantages of using the proposed strategy.

  • Temperature homogenization of a Solar Trough field for performance improvement
    Solar Energy, 2018
    Co-Authors: Adolfo J. Sanchez, Antonio J. Gallego, Juan Manuel Escaño, Eduardo F. Camacho
    Abstract:

    Abstract Optimal operation of Solar Plant is a challenge due to the multiple disturbances affecting the Plant. Research in optimal temperature set-point tracking is extensive whereas research concerning optimal power production under disturbances is not. A Solar Plant has to deal not only with temperature and radiation disturbances but also with dirt accumulated on the collectors which lead to a great disparity in collectors reflectivity. Cleaner collectors produce higher output temperature because of the higher reflectivity. In fact the temperature in this collector may be so high that they have to be defocused with the corresponding energy losses. The paradox is that the most efficient loops may be the one collecting less energy because of defocusing. This paper proposes a new solution based in the manipulation of the loops input valves in order to homogenize the temperatures of the different loops and avoid defocusing. The paper presents an original non linear model based optimization to homogenize the loop temperatures by manipulating the inlet valves of the loops. The nonlinear model is based on a distributed parameters model. In order to perform the optimization, temperature profiles of the loops and its reflectivities are needed. These are obtained by means of a Classification and Regression Trees (CARTs) trained with the full distributed parameters model. Simulations are carried out using a model of the Plataforma Solar de Almeria (PSA) Solar Trough Plant to show the results of the proposed control scheme, temperature homogenization and production benefit.

  • Fault tolerant MPC of a Solar Trough field based on classification and regression trees
    2016 3rd Conference on Control and Fault-Tolerant Systems (SysTol), 2016
    Co-Authors: Adolfo J. Sanchez, Juan M. Escaño, Antonio J. Gallego, Eduardo F. Camacho
    Abstract:

    Direct Solar radiation is important in a Solar Trough Plant because it is the perturbation that affects most the operation. Generally, it is measured locally. Production losses or dangerous situations may occur when controlling a Plant with wrong measurements. A possible solution is to have several pyrheliometers though two problems arise: cost and sensor fusion (complexity). The aim of this paper is to prove that a Solar estimation based on Classification and Regression Trees can be used to design a Fault Tolerant Model Predictive Control strategy capable to work with erroneous values of radiation or even none, avoiding dangerous situations or production losses.

  • Solar radiation estimator and fault tolerant model predictive control of a parabolic-Trough field
    2015 26th Irish Signals and Systems Conference (ISSC), 2015
    Co-Authors: Adolfo J. Sanchez, Juan M. Escaño, Niel Canty, Antonio J. Gallego, Eduardo F. Camacho
    Abstract:

    In this paper we propose an estimator of Solar radiation and a heuristic radiation selector to design a Solar radiation Fault Tolerant Model Predictive Control strategy for Solar Trough Plants. The complete design of the control system proposed has been simulated using the model of ACUREX Solar Trough Plant at the Plataforma Solar de Almería (PSA) using a Gain Scheduling Generalized Predictive Control(GS-GPC) control strategy. Simulation results (estimation/heuristic selector/GS-GPC) of the proposed scheme are compared with simulations of the same GS-GPC controller strategy when using only a pyrheliometer radiation measurement.

Adolfo J. Sanchez - One of the best experts on this subject based on the ideXlab platform.

  • Adaptive incremental state space MPC for collector defocusing of a parabolic Trough Plant
    Solar Energy, 2019
    Co-Authors: Adolfo J. Sanchez, Antonio J. Gallego, Juan Manuel Escaño, Eduardo F. Camacho
    Abstract:

    Abstract Commercial Solar Plants produce energy around a nominal operating point in which the Solar field outlet temperature is high and close to the thermal limit of the heat transfer fluid. The main control of the temperature is carried out by means of the fluid flow-rate that circulates through the Solar field. Defocusing the collectors is normally used as a safety mechanism to avoid exceeding the thermal limit. However, in situations in which the flow is saturated, the control of defocusing the collectors becomes of vital importance and is the system in charge of controlling the Solar field outlet temperature. The paper presents an Adaptive State Space Model Predictive Control strategy with an incremental formulation to control the fourth and third collector defocus angles for field outlet temperature set-point tracking at the nominal operation point, avoiding the Heat Transfer Fluid temperature from exceeding the manufacturer thermal limit (oil degradation). The state space description uses an Unscented Kalman Filter for estimating the non-measurable states. A 50 MW parabolic Solar Trough Plant nonlinear model has been used to design and validate the strategy. Simulation results are presented showing the advantages of using the proposed strategy.

  • Event-based MPC for defocusing and power production of a parabolic Trough Plant under power limitation
    Solar Energy, 2018
    Co-Authors: Adolfo J. Sanchez, Antonio J. Gallego, Juan Manuel Escaño, Eduardo F. Camacho
    Abstract:

    Abstract Optimal operation of a Solar Plant is generally understood as a tracking of the optimal working temperatures which maximize the net electric power. However, a commercial Solar Plant may receive a limitation from the Transmission System Operator due to saturation of the electrical grid. In these situations the Plant moves to an operation mode in which the objective is not maximum production but compliance with the orders of the Transmission System Operator. The paper proposes an Event-Based Gain Scheduling Generalized Predictive Control strategy for electric power production reference tracking when power limitations are imposed by the Transmission System Operator. Gain Scheduling Generalized Predictive Controllers are proposed to control fourth and third collector defocus in order to prevent heating fluid temperature from exceeding the limits of the manufacturer and therefore, avoid oil degradation. A 50 MW parabolic Solar Trough Plant model has been used to design and validate the strategy. Simulation results are presented showing the advantages of using the proposed strategy.

  • Temperature homogenization of a Solar Trough field for performance improvement
    Solar Energy, 2018
    Co-Authors: Adolfo J. Sanchez, Antonio J. Gallego, Juan Manuel Escaño, Eduardo F. Camacho
    Abstract:

    Abstract Optimal operation of Solar Plant is a challenge due to the multiple disturbances affecting the Plant. Research in optimal temperature set-point tracking is extensive whereas research concerning optimal power production under disturbances is not. A Solar Plant has to deal not only with temperature and radiation disturbances but also with dirt accumulated on the collectors which lead to a great disparity in collectors reflectivity. Cleaner collectors produce higher output temperature because of the higher reflectivity. In fact the temperature in this collector may be so high that they have to be defocused with the corresponding energy losses. The paradox is that the most efficient loops may be the one collecting less energy because of defocusing. This paper proposes a new solution based in the manipulation of the loops input valves in order to homogenize the temperatures of the different loops and avoid defocusing. The paper presents an original non linear model based optimization to homogenize the loop temperatures by manipulating the inlet valves of the loops. The nonlinear model is based on a distributed parameters model. In order to perform the optimization, temperature profiles of the loops and its reflectivities are needed. These are obtained by means of a Classification and Regression Trees (CARTs) trained with the full distributed parameters model. Simulations are carried out using a model of the Plataforma Solar de Almeria (PSA) Solar Trough Plant to show the results of the proposed control scheme, temperature homogenization and production benefit.

  • Fault tolerant MPC of a Solar Trough field based on classification and regression trees
    2016 3rd Conference on Control and Fault-Tolerant Systems (SysTol), 2016
    Co-Authors: Adolfo J. Sanchez, Juan M. Escaño, Antonio J. Gallego, Eduardo F. Camacho
    Abstract:

    Direct Solar radiation is important in a Solar Trough Plant because it is the perturbation that affects most the operation. Generally, it is measured locally. Production losses or dangerous situations may occur when controlling a Plant with wrong measurements. A possible solution is to have several pyrheliometers though two problems arise: cost and sensor fusion (complexity). The aim of this paper is to prove that a Solar estimation based on Classification and Regression Trees can be used to design a Fault Tolerant Model Predictive Control strategy capable to work with erroneous values of radiation or even none, avoiding dangerous situations or production losses.

  • Solar radiation estimator and fault tolerant model predictive control of a parabolic-Trough field
    2015 26th Irish Signals and Systems Conference (ISSC), 2015
    Co-Authors: Adolfo J. Sanchez, Juan M. Escaño, Niel Canty, Antonio J. Gallego, Eduardo F. Camacho
    Abstract:

    In this paper we propose an estimator of Solar radiation and a heuristic radiation selector to design a Solar radiation Fault Tolerant Model Predictive Control strategy for Solar Trough Plants. The complete design of the control system proposed has been simulated using the model of ACUREX Solar Trough Plant at the Plataforma Solar de Almería (PSA) using a Gain Scheduling Generalized Predictive Control(GS-GPC) control strategy. Simulation results (estimation/heuristic selector/GS-GPC) of the proposed scheme are compared with simulations of the same GS-GPC controller strategy when using only a pyrheliometer radiation measurement.

Vahab Hassani - One of the best experts on this subject based on the ideXlab platform.

  • performance analysis of thermocline energy storage proposed for the 1 mw saguaro Solar Trough Plant
    Solar Energy, 2006
    Co-Authors: Gregory J Kolb, Vahab Hassani
    Abstract:

    The 1 MW Saguaro Solar parabolic Trough power Plant began operation in December 2005. The Plant will initially operate without an energy storage system. However, recent studies predict a thermocline-type storage should be the most cost-effective storage concept for Solar parabolic Troughs power Plants. If such a system can be successfully demonstrated at Saguaro, future Trough Plants will likely adopt this storage technology. A thermocline storage system for Saguaro has been proposed by Department of Energy (DOE) laboratories and the Solar industry. In this paper, the time-dependent performance of the proposed storage system was evaluated with a new model of the Plant based on the TRNSYS simulation system. Results indicate that the proposed system should work well at Saguaro. The paper describes the TRNSYS model and the engineering insights gleaned from annual performance simulations of the Plant.

Gregory J Kolb - One of the best experts on this subject based on the ideXlab platform.

  • performance analysis of thermocline energy storage proposed for the 1 mw saguaro Solar Trough Plant
    Solar Energy, 2006
    Co-Authors: Gregory J Kolb, Vahab Hassani
    Abstract:

    The 1 MW Saguaro Solar parabolic Trough power Plant began operation in December 2005. The Plant will initially operate without an energy storage system. However, recent studies predict a thermocline-type storage should be the most cost-effective storage concept for Solar parabolic Troughs power Plants. If such a system can be successfully demonstrated at Saguaro, future Trough Plants will likely adopt this storage technology. A thermocline storage system for Saguaro has been proposed by Department of Energy (DOE) laboratories and the Solar industry. In this paper, the time-dependent performance of the proposed storage system was evaluated with a new model of the Plant based on the TRNSYS simulation system. Results indicate that the proposed system should work well at Saguaro. The paper describes the TRNSYS model and the engineering insights gleaned from annual performance simulations of the Plant.