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