簡易檢索 / 詳目顯示

研究生: 黃上維
Huang, Shang-Wei
論文名稱: 具有多段可調控變數之動態系統彈性指標的數值計算策略
A Novel Numerical Strategy for Computing Flexibility Index of Dynamic Systems with Piecewise Constant Manipulated Variables
指導教授: 張珏庭
Chang, Chuei-Tin
學位類別: 碩士
Master
系所名稱: 工學院 - 化學工程學系
Department of Chemical Engineering
論文出版年: 2019
畢業學年度: 107
語文別: 中文
論文頁數: 151
中文關鍵詞: 動態彈性指標操作限制KKT條件基因演算法
外文關鍵詞: Dynamic flexibility analyses, Control constraint, Karush–Kuhn–Tucker condition, Genetic algorithm
相關次數: 點閱:88下載:1
分享至:
查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報
  • 傳統上,程序設計大多都是依據經濟效益作為評量標準,但在現實應用中存在不確定隨機變化的外界干擾,設計過程中採用的參數值可能會在極端狀況下改變,以致使系統無法操作,因此在設計過程中除了考慮成本以外,還需要確保操作的可行性。此外,一般認為程序設計與控制應在製程開發初期就須同時考慮,以便獲得同時具有操作彈性與經濟效益的實際系統。在過去的研究中,雖然已有學者分析在參數不確定情況下動態系統的操作彈性,使設計者能夠以此性能指標作為設計衡量依據。但是,由於傳統頂點法的頂點數量過於龐大,造成難以負荷的計算量。而在傳統活性約束法的數學規劃模型中由於KKT 條件包含大量的限制式和二元變數以致於相應最適化計算難以收斂。另外,值得注意的是,在計算FId的傳統方法中允許瞬時和連續的控制調整也是不切實際的,因此我們在本研究中假設可調控變數可以分段且常數形式表示。我們參考基因演算法及兩種傳統的計算方式,發展出周嚴的動態彈性指標計算流程。具體步驟可描述如下:
    1. 使用活性約束法、GA頂點法或窮舉頂點法來尋找可能的頂點區域。
    2. 使用較細的時間區間離散化窮舉頂點法中的限制式,針對可能的頂點區域進行搜尋與計算出精確的動態彈性指標。
    3. 最後,利用較細的時間區間離散化活性約束法的限制式,並且代入上一步所得結果,以此驗證結果的正確性。
    我們藉由商用軟體Matlab及GAMS,可以有效地執行上述最適化問題。而該計算流程不僅保留了傳統頂點法和活性約束法的優點,更避免了它們的缺點。在本論文中,我們研究並討論幾個案例所得到的結果,以證明解決策略的可行性和準確性。

    The chemical processes, designed on the basis of nominal operating conditions and parameters, have traditionally been evaluated according to economic criteria. This approach often ends up with a plant which may become inoperable in realistic environment if some of the conditions/parameters significantly deviate from their nominal values. Thus, in addition to the financial feasibility, it is equally important to consider the operational flexibility in a practical design. The dynamic flexibility index (FId) have already been well defined to characterize the batch or unsteady operations, and the corresponding dynamic programming models have also be rigorously derived for computing such metrics. However, at the present time, it is still very difficult to apply the traditional vertex method or the active set method to numerically compute FId for even moderately complex systems. This is often due to an overwhelmingly large number of vertices in the former case. On the other hand, since the Karush–Kuhn–Tucker conditions must be included into the mathematical programming model in the latter case, the huge number of real and binary variables usually causes convergence failure. In addition, notice that it is really impractical to allow instantaneous and continuous control adjustments in computing the original version of FId. It is actually more realistic to assume that the manipulated variables are piecewise constant.
    Together with the above assumption and constraints for incorporating additional insights, the above two traditional solution methods are integrated with the genetic algorithm in this work to overcome the aforementioned numerical difficulties. Specifically, the following three-step compotation strategy is proposed:
    1.Identify the approximate region(s) of candidate vertexes by using the dynamic active-set method, the dynamic vertex method solved with genetic algorithm, or the dynamic vertex method solved with exhaustive enumeration.
    2.Use a refined time interval to discretize the constraints in vertex method and carry out the corresponding computation procedure by fixing the identified regions of candidate vertexes.
    3.Use a refined time interval to discretize the constraints in KKT conditions and fix the time profiles of control variables and uncertain parameters identified in the previous step to carry out dynamic active set method again
    The above optimization computations can be readily implemented with MATLAB and GAMS. This strategy not only retains the advantages from traditional vertex method and the active set method but also avoid their shortcomings .The numerical results obtained in several case studies are reported in this thesis to demonstrate the feasibility and accuracy of the solution strategy.

    目錄 口試委員會審定書 # 摘要 i Extended Abstract iii 誌謝 x 目錄 xi 表目錄 xiv 圖目錄 xv 第一章 緒論 1 1.1 研究動機 1 1.2 文獻回顧 1 1.3 研究目的 3 1.4 組織章節 3 第二章 操作彈性分析 4 2.1 計算彈性指標的數學規劃模型 4 2.1.1 穩態彈性指標之定義 4 2.1.2 動態彈性指標之定義 6 2.2 數值求解方法 8 2.2.1 穩態彈性指標的計算 8 2.2.2 動態彈性指標的計算 11 第三章 實際動態系統之操作彈性 17 3.1 動態系統中之實際限制 17 3.2 頂點法之額外限制-以窮舉方式求解 20 3.3 頂點法之額外限制-以基因演算法求解 23 3.4 活性約束法之額外限制式 26 3.4.1 連續穩態操作 26 3.4.2 時變性操作 27 3.5 計算流程 28 3.6 簡單案例-單水槽緩衝系統 31 3.6.1 連續穩態操作 32 3.6.2 時變性操作-階梯型 46 3.6.3 時變性操作-平滑型 53 第四章 實際案例 60 4.1 雙水槽液位緩衝系統 60 4.1.1 連續穩態操作 62 4.1.2 時變性操作-階梯型 66 4.1.3 時變性操作-平滑型 69 4.2 太陽能驅動薄膜蒸餾海水淡化程序(SMDDS) 73 4.2.1 太陽能驅動薄膜蒸餾海水淡化系統之各單元模式 75 4.2.2 參數與規格 79 4.2.3 太陽能吸收器設計規格對程序彈性的影響 83 4.2.4 平滑型不確定參數下SMDDS之各項操作彈性 96 4.3 生物反應器-酒精發酵槽系統(Alcoholic fermentation process) 110 4.3.1 酒精發酵槽及數學模型介紹 111 4.3.2 連續穩態操作 114 4.3.3 時變性操作 125 第五章 結論與展望 137 5.1 研究結論 137 5.2 未來展望 137 參考文獻 139 附錄一:GA頂點法之Matlab程式碼 143

    Adi, V. S. K., and Chang, C. T., A mathematical programming formulation for temporal flexibility analysis. Comput. Chem. Eng. 2013, 57, 151.
    Adi, V. S. K., and Chang, C. T., Development of flexible designs for PVFC hybrid power systems. Renew. Energ. 2015, 74, 176.
    Brengel, D. and Seider, W., Coordinated design and control optimization of nonlinear processes. Computers & Chemical Engineering. 1992, 16(9), 861.
    Ben Bacha, H., Dammak, T., Ben Abdalah, A. A., Maalej, A. Y., and Ben Dhia, H., Desalination unit coupled with solar collectors and storage tank: modeling and simulation. Desalination. 2007, 206, 341.
    Chang, H., Wang, G. B., Chen, Y. H., Li, C. C., and Chang, C. L., Modeling and optimization of a solar driven membrane distillation desalination system. Renew. Energ. 2010, 35, 2714.
    Chang, H., Lyu, S. G., Tsai, C. M., Chen, Y. H., Cheng, T. W., and Chou, Y. H., Experimental and simulation study of a solar thermal driven membrane distillation desalination process. Desalination. 2012, 286, 400.
    Dimitriadis, V. D., and Pistikopoulos, E. N., Flexibility analysis of dynamic system. Ind. Eng. Chem. Res. 1995, 34, 4451.
    Dimitriadis, V. D., Shah, N., and Pantelides, C. C., Modeling and safety verification of discrete/continuous processing systems. AIChE J. 1997, 43, 1041
    Fabro, J. A., & Arruda, L. V., Fuzzy-neuro predictive control, tuned by genetic algorithms, applied to a fermentation process. In Proceedings of the 2003 IEEE International Symposium on Intelligent Control (pp. 194-199). IEEE..
    Grossmann, I. E., and Floudas, C. A., Active constraint strategy for flexibility analysis in chemical process. Comput. Chem. Eng. 1987, 11, 675.
    Kabbaj, N., Nakkabi, Y., & Doncescu, A., Analytical and knowledge based approaches for a bioprocess supervision. Knowledge-Based Systems. 2010. 23(2), 116-124.
    Kuo, Y. C., and Chang, C. T., On heuristic computation and application of flexibility indices for unsteady process design. Industrial & Engineering Chemistry Research. 2016. 55(3), 670.
    Lima, F. V., and Georgakis, C., Design of output constraints for model-based non-square controllers using interval operability. J. Process Contr. 2008, 18, 610.
    Lima, F. V., Georgakis, C., Smith, J. F., Schnelle, P. D., and Vinson, D. R., Operability-based determination of feasible control constraints for several high-dimensional nonsquare industrial processes. AIChE J. 2009, 1249.
    Lima, F. V., Jia, Z., Ierapetritou, M., and Georgakis, C., Similarities and differences between the concepts of operability and flexibility: the steady-state case. AIChE J. 2010, 56, 702.
    Maher, M., Modélisation et élaboration d'algorithmes d'estimation et de commande: application à un bioprocédé. 1995 (Doctoral dissertation, Toulouse 3).
    Malcom, A., Polan, J., Zhang, L., Ogunnaike, B. A., and Linninger, A. A., Integrating systems design and control using dynamic flexibility analysis. AIChE J. 2007, 53, 2048.
    MendonçA, M., Angelico, B., Arruda, L. V., & Neves Jr, F., A dynamic fuzzy cognitive map applied to chemical process supervision. Engineering Applications of Artificial Intelligence. 2013, 26(4), 1199-1210.
    Serra, A., Strehaiano, P., & Taillandier, P., Influence of temperature and pH on Saccharomyces bayanus var. uvarum growth; impact of a wine yeast interspecific hybridization on these parameters. International journal of food microbiology. 2005, 104(3), 257-265.
    Swaney, R. E., and Grossmann, I. E., An index for operational flexibility in chemical process design part I: formulation and theory. AIChE J. 1985, 31, 621.
    Swaney, R. E., and Grossmann, I. E., An index for operational flexibility in chemical process design part II: formulation and theory. AIChE J. 1985, 31, 631.
    Sanchez-Sanchez, K., and Ricardez-Sandoval, L., Simultaneous design and control under uncertainty using model predictive control. Industrial & Engineering Chemistry Research. 2013, 52(13), 4815.
    Vasilache, A., Dahhou, B., Roux, G., & Goma, G., Classification of fermentation process models using recurrent neural networks. International Journal of Systems Science. 2001, 32(9), 1139-1153.
    Wu, R. S., and Chang, C. T., Development of mathematical programs for evaluating dynamic and temporal flexibility indices based on KKT conditions. Journal of the Taiwan Institute of Chemical Engineers. 2017, 73, 86.
    Zbigniew Michalewicz., Genetic Algorithms + Data Structures = Evolution Programs (3rd ed.). Univ. of North Carolina, Charlotte. ISBN:3-540-60676-9
    Zhou, H., Li, X. X., Qian, Y., Chen, Y., and Kraslawski, A., Optimizing the initial conditions to improve the dynamic flexibility of batch processes. Ind. Eng. Chem. Res. 2009, 48, 6321.

    下載圖示 校內:2022-01-01公開
    校外:2022-01-01公開
    QR CODE