Based on the more electric ship (MES) concept, conventional mechanical, hydraulic, and pneumatic power transfer systems are replaced by electrical systems in different sea vehicles. Considering different levels of power requirements of various electrical loads and for the achievement of compact, light, safe, and efficient power supplies, implementation of multiconverter power electronics based power systems is the most feasible option in the development of advanced navy vehicles. This paper presents a modular approach for the modeling and simulation of multiconverter MES power systems based on the generalized state space averaging method. MES power systems may consist of many individual converters connected together to form large and complex systems. In addition to simplifying the analysis procedure, by using the proposed method, time step for analysis of the system can be increased. Therefore, required computation time and computer memory for complex systems can be reduced considerably. In this paper, after introducing the proposed approach, results of applying the method to a representative system are presented. Experimental results are also provided to verify the proposed technique.