Stochastic dynamic load-sharing analysis of the closed differential planetary transmission gear system by the Monte Carlo method

The closed differential planetary transmission system features a high speed-ratio, and a compact structure for transmitting power through a dual-path. Further, the power is usually shared unevenly among the planetary/star gears for manufacturing error. Furthermore, the dual-path causes power confluence aggravating uneven load distribution, and leading to transmission failure. In this regard, a widely used analysis method is adopting the maximum tolerance for critical parameters. However, manufacturing error are stochastic in engineering practice. Thus, this study investigates error randomness in dynamic load-sharing behavior. First, a stochastic multi-body dynamics model of a closed differential planetary transmission is established. Next, the sampled and stochastic distributions of the load sharing behavior are obtained and compared with the Taguchi method. Then, the effect of manufacturing and assembling the tolerance zone on the load-sharing performance is investigated. Lastly, the experiment for the main gearbox of a MW wind turbine is used to verify the results determined using the stochastic errors. Notably, the method using the maximum errors overestimates the load-sharing coefficients by 92% for the differential stage, and by 100% for the closed stage. (c) 2021 Published by Elsevier Ltd.

Automated summary

The closed differential planetary transmission system features a high-speed ratio and compact structure, but suffers from uneven load sharing and excessive errors. This study investigates the impact of error randomness on load-sharing behavior through establishing a stochastic multi-body dynamics model and comparing different methods.