Abstract: During the operation of Heat exchanger network (HEN), for operating conditions are always varied, the bypass optimal control is considered as an effective method to adjust the temperatures and saving energy. However, locations of bypasses are derived without the verification by the control theory. Therefore, it is very necessary to analysis the structural characteristics of heat exchanger networks. Firstly, based on the topology theory, the structural states configuration and array are presented by using the structural model of the HEN. Then, the HEN structural controllability, the structural control intension and redundancy degree are analyzed. The results indicate that the bypass on downstream is less controllability than that on upstream; structural control intension is affected by the corresponding bypass location; and the using of the coupling channel may affect the redundancy degree and the controllability significantly. The analysis of case study demonstrated this method can be used to testify the controllability of the HEN with bypass optimal control, and significantly reduce the analysis complication on complex structural controllability analysis. This method also indicated a novel idea for applying control theory on engineering process.

Key words: heat exchanger network, bypass control, structural controllability; structural control intensity, redundancy

摘要： 换热网络的旁路控制是调节物流出口温度、节能降耗的有效方法，旁路位置的确定往往是实现最优控制的关键。因此，从控制理论的角度，对比分析具有旁路控制的换热网络结构可控性等结构特性。首先，基于图论的概念通过换热网络结构模型，求取其状态结构图以及状态结构阵。然后根据求解结果分析网络的结构可控性以及控制结构的强度与冗余度。通过实例对比分析证明结构可控性分析的方法从控制理论的角度分析论证了换热网络旁路优化设计结果的可控性，并且方法从换热网络结构模型入手简化了求解过程，为换热网络的旁路优化控制提供一种新的思路。

关键词: 换热网络, 旁路控制, 结构可控性, 结构强度, 冗余度