Economic Model Predictive Control Using Data-Based Empirical Models - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Economic Model Predictive Control Using Data-Based Empirical Models write by ANAS W. I. ALANQAR. This book was released on 2017. Economic Model Predictive Control Using Data-Based Empirical Models available in PDF, EPUB and Kindle. The increasingly competitive and continuously changing world economy has made it necessary to exploit the economic potential of chemical processes which has led engineers to economically optimize process operation to provide long-term economic growth. Approaches for increasing the profitability of industrial processes include directly incorporating process economic considerations into the system's operation and control policy. A fairly recent control strategy, termed economic model predictive control (EMPC), is capable of coordinating dynamic economic plant optimization with a feedback control policy to allow real-time energy management. The key underlying assumption to design and apply an EMPC is that a rocess/system dynamic model is available to predict the future process state evolution. Constructing models of dynamical systems is done either through first-principles and/or from process input/output data. First-principle models attempt to account for the essential mechanisms behind the observed physico-chemical phenomena. However, arriving at a first-principles model may be a challenging task for complex and/or poorly understood processes in which system identification serves as a suitable alternative. Motivated by this, the first part of my doctoral research has focused on introducing novel economic model predictive control schemes that are designed utilizing models obtained from advanced system identification methods. Various system identification schemes were investigated in the EMPC designs including linear modeling, multiple models, and on-line model identification. On-line model identification is used to obtain more accurate models when the linear empirical models are not capable of capturing the nonlinear dynamics as a result of significant plant disturbances and variations, actuator faults, or when it is desired to change the region of operation. An error-triggered on-line model identification approach is introduced where a moving horizon error detector is used to quantify prediction error and trigger model re-identification when necessary. The proposed EMPC schemes presented great economic benefit, precise predictions, and significant computational time reduction. These benefits indicate the effectiveness of the proposed EMPC schemes in practical industrial applications. The second part of the dissertation focuses on EMPC that utilizes well-conditioned polynomial nonlinear state-space (PNLSS) models for processes with nonlinear dynamics. A nonlinear system identification technique is introduced for a broad class of nonlinear processes which leads to the construction of polynomial nonlinear state-space dynamic models which are well-conditioned with respect to explicit numerical integration methods. This development allows using time steps that are significantly larger than the ones required by nonlinear state-space models identified via existing techniques. Finally, the dissertation concludes by investigating the use of EMPC in tracking a production schedule. Specifically, given that only a small subset of the total process state vector is typically required to track certain production schedules, a novel EMPC is introduced scheme that forces specific process states to meet the production schedule and varies the rest of the process states in a way that optimizes process economic performance
Economic Model Predictive Control of Nonlinear Process Systems Using Empirical Models
Economic Model Predictive Control of Nonlinear Process Systems Using Empirical Models - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Economic Model Predictive Control of Nonlinear Process Systems Using Empirical Models write by Anas Wael Alanqar. This book was released on 2015. Economic Model Predictive Control of Nonlinear Process Systems Using Empirical Models available in PDF, EPUB and Kindle. Economic model predictive control (EMPC) is a feedback control technique that attempts to tightly integrate economic optimization and feedback control since it is a predictive control scheme that is formulated with an objective function representing the process economics. As its name implies, EMPC requires the availability of a dynamic model to compute its control actions and such a model may be obtained either through application of first-principles or though system identification techniques. However, in industrial practice, it may be difficult in general to obtain an accurate first-principles model of the process. Motivated by this, in the present work, Lyapunov-based economic model predictive control (LEMPC) is designed with an empirical model that allows for closed-loop stability guarantees in the context of nonlinear chemical processes. Specifically, when the linear model provides a sufficient degree of accuracy in the region where time-varying economically optimal operation is considered, conditions for closed-loop stability under the LEMPC scheme based on the empirical model are derived. The LEMPC scheme is applied to a chemical process example to demonstrate its closed-loop stability and performance properties as well as significant computational advantages.
Economic Model Predictive Control
Economic Model Predictive Control - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Economic Model Predictive Control write by Helen Durand. This book was released on 2018-06-19. Economic Model Predictive Control available in PDF, EPUB and Kindle. Economic Model Predictive Control (EMPC) is a control strategy that moves process operation away from the steady-state paradigm toward a potentially time-varying operating strategy to improve process profitability. The EMPC literature is replete with evidence that this new paradigm may enhance process profits when a model of the chemical process provides a sufficiently accurate representation of the process dynamics. Systems using EMPC often neglect the dynamics associated with equipment and are often neglected when modeling a chemical process. Recent studies have shown they can significantly impact the effectiveness of an EMPC system. Concentrating on valve behavior in a chemical process, this monograph develops insights into the manner in which equipment behavior should impact the design process for EMPC and to provide a perspective on a number of open research topics in this direction. Written in tutorial style, this monograph provides the reader with a full literature review of the topic and demonstrates how these techniques can be adopted in a practical system.
Data-Based Nonlinear Model Identification in Economic Model Predictive Control
Data-Based Nonlinear Model Identification in Economic Model Predictive Control - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Data-Based Nonlinear Model Identification in Economic Model Predictive Control write by Laura Giuliani. This book was released on 2018. Data-Based Nonlinear Model Identification in Economic Model Predictive Control available in PDF, EPUB and Kindle. Many chemical/petrochemical processes in industry are not completely modeled from a first-principles perspective because of the complexity of the underlying physico-chemical phenomena and the cost of obtaining more accurate, physically relevant models. System identification methods have been utilized successfully for developing empirical, though not necessarily physical, models for advanced model-based control designs such as model predictive control (MPC) for decades. However, a fairly recent development in MPC is economic model predictive control (EMPC), which is an MPC formulated with an economics-based objective function that may operate a process in a dynamic (i.e., off steady-state) fashion, in which case the details of the process model become important for obtaining sufficiently accurate state predictions away from the steady-state, and the physics and chemistry of the process become important for developing meaningful profit-based objective functions and safety-critical constraints. Therefore, methods must be developed for obtaining physically relevant models from data for EMPC design. While the literature regarding developing models from data has rapidly expanded in recent years, many new techniques require a model structure to be assumed a priori, to which the data is then fit. However, from the perspective of developing a physically meaningful model for a chemical process, it is often not obvious what structure to assume for the model, especially considering the often complex nonlinearities characteristic of chemical processes (e.g., in reaction rate laws). In this work, we suggest that the controller itself may facilitate the identification of physically relevant models online from process operating data by forcing the process state to nonroutine operating conditions for short periods of time to obtain data that can aid in selecting model structures believed to have physical significance for the process and, subsequently, identifying their parameters. Specifically, we develop EMPC designs for which the objective function and constraints can be changed for short periods of time to obtain data to aid in model structure selection. For one of the developed designs, we incorporate Lyapunov-based stability constraints that allow closed-loop stability and recursive feasibility to be proven even as the online "experiments" are performed. This new design is applied to a chemical process example to demonstrate its potential to facilitate physics-based model identification without loss of closed-loop stability. This work therefore reverses a question that has been of interest to the control community (i.e., how new techniques for developing models from data can be useful for control of chemical processes) to ask how control may be utilized to impact the use of these techniques for the identification of physically relevant process dynamic models that can aid in improving process operation and control for economic and safety purposes.
New Directions on Model Predictive Control
New Directions on Model Predictive Control - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook New Directions on Model Predictive Control write by Jinfeng Liu. This book was released on 2019-01-16. New Directions on Model Predictive Control available in PDF, EPUB and Kindle. This book is a printed edition of the Special Issue "New Directions on Model Predictive Control" that was published in Mathematics
