Large-scale High Voltage Direct Current (HVDC) cross-region transmission and AC/DC hybrid transmission make the dynamic characteristics of power system more complex. Simulation is a powerful method for studying AC/DC hybrid grids. Electromechanical and electromagnetic transient simulation has been widely used in power system simulation analysis. Electromechanical transient simulation can use large-step to simulate the components of power frequency with infrequent switching, so it can simulate a large scale power system. Electromagnetic transient simulation is suitable for modeling the components’ details considering frequent switching in the small scale power system by small-step. Usually it is a contradiction between system’s scale and component’s precision in the simulation. In order to analyze the influence of HVDC system control model in hybrid power system and combine advantages of two simulation methods, this paper establishes a large-scale AC/DC hybrid system in Advanced Digital Power System Simulator (ADPSS), which is developed by China Electric Power Research Institute. The simulation differences are analyzed considering the detail modeling of the pulse generator and the constant voltage controller. It is verified by the extended system based on IEEE 39-bus. It will provide a more efficient and accurate simulation modern for AC/DC hybrid systems with a large number of power electronic devices. This work is supported by National Key Research and Development Program of China (No. 2017YFB0902000).