过程层是智能变电站区别于常规变电站的重要特点之一，其组网方案直接影响保护、控制功能的实现和网络设备的投资。对几类典型过程层网络拓扑结构、采样值传输协议进行了分析比较，确定适合智能变电站工程的过程层网络方案；结合变电站现状，给出设备选型、功能需求等方面的设计实例。

Process level is one of the important characteristics of smart substation, which is different from conventional substation. Its networking scheme directly affects the realization of protection and control function and the investment of network equipments. Based on the analysis and comparison of several kinds of typical process-level network topological structures and sampling value transmission protocols, a suitable process-level network scheme for smart substation is suggested in this paper. Combined with the current situation of substations, the design examples are also presented in aspects of equipment selection and functional requirements.