SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2022, Vol. 47 ›› Issue (7): 231-244.DOI: 10.1016/j.cjche.2021.08.022

• Full Length Article • 上一篇    下一篇

Two-tier control structure design methodology applied to heat exchanger networks

Siwen Gu1,2,3, Lei Zhang1, Yu Zhuang1, Weida Li1, Jian Du1, Cheng Shao3   

  1. 1. Institute of Chemical Process Systems Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China;
    2. Jiangsu Collaborative Innovation Center for Cultural Creativity, School of Photoelectric Engineering, Changzhou Institute of Technology, Changzhou 213032, China;
    3. Institute of Advanced Control Technology, School of Control Science and Engineering, Dalian University of Technology, Dalian 116024, China
  • 收稿日期:2020-11-27 修回日期:2021-07-25 出版日期:2022-07-28 发布日期:2022-08-19
  • 通讯作者: Jian Du,E-mail:dujian@dlut.edu.cn
  • 基金资助:
    The authors would like to gratefully acknowledge financial support from Jiangsu Collaborative Innovation Center for Cultural Creativity (XYN1911), the National Natural Science Foundation of China (22008023; 21776035) and Natural Science Foundation of Jiangsu Education Department (20KJB510041).

Two-tier control structure design methodology applied to heat exchanger networks

Siwen Gu1,2,3, Lei Zhang1, Yu Zhuang1, Weida Li1, Jian Du1, Cheng Shao3   

  1. 1. Institute of Chemical Process Systems Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China;
    2. Jiangsu Collaborative Innovation Center for Cultural Creativity, School of Photoelectric Engineering, Changzhou Institute of Technology, Changzhou 213032, China;
    3. Institute of Advanced Control Technology, School of Control Science and Engineering, Dalian University of Technology, Dalian 116024, China
  • Received:2020-11-27 Revised:2021-07-25 Online:2022-07-28 Published:2022-08-19
  • Contact: Jian Du,E-mail:dujian@dlut.edu.cn
  • Supported by:
    The authors would like to gratefully acknowledge financial support from Jiangsu Collaborative Innovation Center for Cultural Creativity (XYN1911), the National Natural Science Foundation of China (22008023; 21776035) and Natural Science Foundation of Jiangsu Education Department (20KJB510041).

摘要: Because of its paramount importance in the successful industrial control strategy of a given heat exchanger network (HEN), the control structure designs for providing appropriate manipulated variable (MV) and controlled variable pairings have received considerable attention. However, quite frequently HENs with such control structures face the problem of hard constraints, typically holding the HENs at less controlled operating space. So both the MV pairings and the above control pairings should be considered to design a control structure. This paper investigates the systematic incorporation of the two pairings, and presents a methodology for designing such two-tier control structure. This is developed based on the sequential strategy, coupling an indirect-tier with direct-tier control structure design, wherein the intention is realized in the former stage and the latter is implemented for further optimization. The MV identification and pairing are achieved through variations in heat load of heat exchangers to design the indirect-tier control structure. Then the direct-tier control structure is followed the relative gain array pairing rules. With the proposed methodology, on the one hand, it generates an explicit connection between the MV pairings and the HEN configuration, and the quantitative interaction measure is improved to avoid the multiple solutions to break the relationship among all the control pairings into individuals; on the other hand, a two-tier control structure reveals control potentials and control system design requirements, this may avoid complex and economically unfavourable control and HEN structures. The application of proposed framework is illustrated with two cases involving the dynamic simulation analysis, the quantitative assessment and the random test.

关键词: Heat exchanger networks (HENs), Controllability, Two-tier control structure, Manipulated variable pairing, Control pairing

Abstract: Because of its paramount importance in the successful industrial control strategy of a given heat exchanger network (HEN), the control structure designs for providing appropriate manipulated variable (MV) and controlled variable pairings have received considerable attention. However, quite frequently HENs with such control structures face the problem of hard constraints, typically holding the HENs at less controlled operating space. So both the MV pairings and the above control pairings should be considered to design a control structure. This paper investigates the systematic incorporation of the two pairings, and presents a methodology for designing such two-tier control structure. This is developed based on the sequential strategy, coupling an indirect-tier with direct-tier control structure design, wherein the intention is realized in the former stage and the latter is implemented for further optimization. The MV identification and pairing are achieved through variations in heat load of heat exchangers to design the indirect-tier control structure. Then the direct-tier control structure is followed the relative gain array pairing rules. With the proposed methodology, on the one hand, it generates an explicit connection between the MV pairings and the HEN configuration, and the quantitative interaction measure is improved to avoid the multiple solutions to break the relationship among all the control pairings into individuals; on the other hand, a two-tier control structure reveals control potentials and control system design requirements, this may avoid complex and economically unfavourable control and HEN structures. The application of proposed framework is illustrated with two cases involving the dynamic simulation analysis, the quantitative assessment and the random test.

Key words: Heat exchanger networks (HENs), Controllability, Two-tier control structure, Manipulated variable pairing, Control pairing