Dynamic Security Management of Edge Devices Based on Zero Trust Architecture in Modern Power Systems

Modern substations rely on networked edge devices for monitoring and control, but this connection method also brings higher network security risks. Traditional perimeter-based protection methods have been unable to effectively deal with complex intrusion behaviors that spread within trusted networks. This paper proposes a dynamic security management architecture for edge devices based on the zero trust principle, which continuously authenticates and monitors the behavior of each device and its data flow, and implements adaptive access control policies. First, a simulation system of a smart substation is designed. Second, the key elements of the zero trust architecture are integrated, including continuous identity verification, micro-segmentation based on software-defined networks, real-time anomaly detection modules, and automatic response mechanisms for threat isolation. Experimental results in simulated attack scenarios show that the method proposed in this paper is superior to the traditional perimeter defense system in terms of attack detection accuracy, false alarm rate, and response timeliness, and can provide a practical technical path for improving the network security protection capabilities of new substations.