Axially Staggered Compound Planetary Gear for Wind Turbine Torque Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional wind turbine gear transmission units face challenges in achieving higher power output at lower costs and reduced weight, as increased torque requirements lead to heavier and more costly gear systems, necessitating a solution to enhance torque density and reduce nacelle and tower weight.
Innovation Solution
A compound planetary gear transmission unit with a stationary ring gear, multiple stages of planets, and a torque differential mechanism, featuring axially staggered second stage planets to maximize gear ratio and torque density, while minimizing weight and cost through flexible pin connections and double helical coupling for load sharing and alignment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If conventional planetary arrangements with multiple stages are used to address high torque and low input RPM, then the torque transmission capability is improved, but the weight of the gear transmission unit increases
Solution Approach 1:
The gear transmission unit is divided into two distinct stages: a first stage planetary gear set and a second stage planetary gear set. Each stage handles a portion of the total torque, allowing the system to achieve high torque transmission capability without requiring a single oversized gear set. The first stage planets engage the ring gear while the second stage planets are driven by the first stage, creating a segmented torque path that reduces the weight of individual components while maintaining overall torque capacity.
2Force
If the number of planets is increased to handle higher torque loads, then the torque capacity is improved, but the device complexity increases
Solution Approach 1:
Instead of using a single stage with many planets, the system segments the planetary gears into two stages with fewer planets each. The first stage has multiple planets engaging the ring gear, and the second stage has planets driven by the first stage planets. This segmentation allows the system to handle high torque loads through a cascaded approach rather than concentrating all planets in one stage, thereby reducing complexity.
Solution Approach 2:
The patent introduces an axial dimension to the planetary arrangement by staggering the second stage planets axially relative to the first stage planets. This axial offset allows the second stage planets to be driven by the first stage planets through a three-dimensional torque path, effectively adding a spatial dimension to the torque transmission and allowing for more efficient load distribution without increasing the number of planets in each individual stage.
Data Source
AI summary
A compound planetary gear transmission unit includes a second stage with axially staggered planets.