Aiming to grasp operating performance of gas turbine generator set in power system, this paper proposed a universal dynamic model based on GGOV1 (general governor) structure and AC8B excitation model using Matlab/Simulink. An application example is given with parameters of a gas turbine generator set which is already put into operation on Jinzhou 25-1 southern CEPF offshore platform, and the modular fine model is established for gas turbine (i.e. prime mover), exciter and main generator (i.e. exciter synchronous motor). Through simulation test, rotation speed, terminal voltage, field voltage, output mechanical power of gas turbine, and gas consumption can be monitored effectively. Eventually, the simulation results show that the established model can directly reflect the linkage between the physical quantities of the set when the load changes dynamically, which verifies the universality of the model.