This paper explores the development of relay protection technology in smart grids, analyzing its applications in intelligent algorithms, digital devices, and automated coordination. Firstly, considering the fuzziness and uncertainty of the boundary division of relay protection evaluation levels, a relay protection risk assessment method based on normal cloud model has been. Relay protection systems are essential in maintaining the safety and reliability of modern electrical grids. As technology advances and grids become smarter, the tools used to test and maintain these systems, such as the relay test set, are evolving to meet new challenges. Nowhere is that clearer than in the challenge to. Relay systems protect high-voltage equipment and transmission lines to ensure safe, stable systems.