This paper discusses the necessity of establishing the dynamic physical model system of UHV AC transmission system， and introduces the construction of UHV transmission lines， transformers， shunt reactors， and so on. A lot of dynamic simulation experiments are done on transmission lines and transformers with special features on UHV. The unique problems and phenomena arisen in the UHV system are studied. The experiments show that the result of the physical model is identical with the theoretical analysis on the prototype， and the physical model can be used to study the transient characteristics on UHV system and the characteristics of secondary devices.