Vibration Performance and Vibration Reduction Optimization of Diesel Generator Sets for Diesel Locomotives

The power package of high-speed internal combustion units generates complex excitation forces during operation. These forces cause excessive vibration in the driver’s cab, negatively affecting the driver’s working conditions. Therefore, optimizing the isolation system design is essential. This study established a rigid body dynamic model of a single-layer isolation system to determine initial stiffness parameters. A refined finite element (FE) model of the diesel locomotive body was also developed to analyze vibration characteristics. Using the global response surface method, multi-objective optimization was performed. The three-dimensional stiffness of the isolator served as the design variable, while the maximum force transmissibility at the vehicle reference point was the optimization objective. The optimization accuracy was verified through FE modeling, experiments, and simulations considering coupled wheel–rail excitations. Results showed that the force transmissibility at the cab’s center floor decreased from 44.05% to 32.65%. Furthermore, the comfort index met the requirements under all working conditions. These findings indicate that the proposed design method effectively improves the efficiency of the power pack isolation system and provides a valuable reference for future designs.