Abstract: With the rapid growth of distribution network load, distributed energy and electric vehicles, the traditional distribution network structure and regulation modes are facing huge challenges. Problems such as unbalanced feeder power, heavy overload of transformers, and difficulties in urban power transmission and distribution capacity expansion are increasingly prominent. The flexible multi-state switch technology of distribution networks brings the possibility to solve the above problems. Taking the typical application scenario of flexible interconnection in the distribution network area as the starting point, the paper analyzes the different application scenarios applicable to the flexible multi-state switch, and studies the application background and advantage of the flexible multi-state switch in different application scenarios. The functional requirements, technical support, demonstration application and research difficulties in typical application scenarios are analyzed. The key problems and challenges facing different application scenarios are given, and the future research areas of flexible multi-state switches are prospected.