In this paper, two novel brushless excitation methods for wound rotor excitation synchronous generators are proposed in this paper. Compared with the electric excitation synchronous generators with an exciter, these two kinds of generators can integrate the function of the exciter into the main generator. The exciter can be eliminated. The axial length of the generation system can be shorten. The structures and operating principles of two novel generators are introduced. The magnetic field distributions are obtained by Finite Element Analysis. The operating characteristics of two generators are simulated and compared. These two brushless excitation methods can be applied in the areas such as aerospace generation system, wind power generator, electric vehicles and so on.