Numerical and experimental investigations of proper orthogonal decomposition for vibration energy distribution analysis of a two-stage planetary gear system

Vibration energy is used to analyze the vibration distribution characteristics and transmission characteristics with one index, and can comprehensively evaluate the system vibration characteristics. This paper proposes an energy proper orthogonal decomposition (ePOD) method to analyze the vibration distribution characteristics of a two-stage planetary gear system. The application of the ePOD method in analyzing the vibration energy distribution of the system is explored with numerical simulation and experiment, and the speed influence is considered. The physical meanings of the energy proper orthogonal mode (ePOM) and the energy proper orthogonal value (ePOV) are expounded. The first-order ePOM characteristics are the same as the natural energy modal characteristics in different rotational speeds, and the contribution of resonance to the system vibration is expressed by the first-order ePOV. The proposed method can effectively identify the main vibration energy characteristics and can be used to analyse and optimise of planetary gear systems.