The lumped parameter method is used to model the components of a marine diesel-electric hybrid propulsion system. Modular modeling and five basic models of torsional vibration are used to establish the torsion of the diesel-electric hybrid propulsion system with a nonlinear components vibration mathematical model. In order to include the nonlinear parts of the marine diesel-hybrid propulsion shafting torsional vibration system characteristics, by combining the perturbation method with the advantages and disadvantages of the harmonic method, a perturbation-harmonic method is presented to solve the diesel-electric hybrid propulsion shafting free vibration characteristics. At the same time, the nonlinear vibration characteristics of the hybrid propulsion shaft system are calculated and analyzed using the incremental harmonic balance method. In order to verify the correctness of the theoretical method of hybrid propulsion system, the correctness of the vibration model and method is verified by carrying out actual tests on a 10,000-ton marine surveillance ship. In order to verify the mathematical model of the ship diesel-hybrid propulsion system and the correctness of the theoretical calculation method, the torsional vibration test is carried out by a strain gauge method for a 10,000-ton marine propulsion shaft. The correctness of the torsional vibration mathematical model and the calculation method is verified by comparing the torsional vibration test data and the theoretical calculation data of the ship propulsion shaft system, which provides the theoretical significance for the calculation and analysis of the torsional vibration of the ship propulsion shaft system.
