鉴于单元Ex分析法的局限性,指出了研究系统Ex分析法的必要性。提出了黑箱网络、过程分解、能量关联三种系统模型,重点阐述了作为过程分解模型基础的基元过程的Ex损计算方法。建议以系统的热力学完善度ε、系统的Ex效率η_(ex)和比Ex效率系数ζ作为系统Ex分析的评价准则,并给出了计算公式。 In view of the limitations of the unit Ex analysis method, the necessity of the research system Ex analysis method was pointed out. The three system models of black-box network, process decomposition and energy correlation are proposed, and the Ex damage calculation method of the elementary process as the basis of the process decomposition model is elaborated. It is suggested that the thermodynamic refinement ε of the system, the Ex η_(ex) and the Ex efficiencies ζ of the system be used as evaluation criteria for the system Ex analysis, and the calculation formulas are given.