Abstract: In substation operations, the safety and stability of power systems are paramount. As the industry adopts the new operational model of "unmanned operation with centralized monitoring", tracking equipment performance and health status has become particularly critical. To address challenges in current technologies—such as monitoring difficulties during power outages or severe weather, and incomplete data—this paper proposes a differential monitoring approach for substation control systems. This method comprehensively monitors equipment conditions and anomalies, enhances monitoring efficiency, ensures quality, and enables centralized equipment surveillance in critical scenarios. It also improves equipment status management and power supply reliability in special situations.