Coaxial Starter-Generator for Turbine Engine Auxiliary Gearbox
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing auxiliary gearboxes in turbine engines are limited in supporting multiple starting components and modes, leading to constraints in torque and electrical power capacity, which necessitates costly redesigns or changes in the gearbox and turbine engine pairing.
Innovation Solution
A dual mode electric starter/generator (DMSG) system that integrates both electric and air turbine starters, allowing for coaxial or selectively coupled configurations to share a single pad on the auxiliary gearbox, enabling dual starting modes without altering the existing gearbox, and allowing the electric starter to function as a generator for increased power generation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a single starter is used in the auxiliary gearbox, then the gearbox structure remains simple, but the torque and electrical power capacity are limited
Solution Approach 1:
The auxiliary gearbox is designed with a universal pad structure that can accommodate multiple types of starters (electric starter, air turbine starter, or both simultaneously). The pad is configured with a bearing assembly and mounting features that are compatible with different starter configurations, allowing the same gearbox to support single-starter or dual-starter arrangements without requiring structural modifications.
2Power
If dual starters are added to increase torque and power capacity, then the starting capability is improved, but the gearbox must be redesigned
Solution Approach 1:
The dual starter configuration is implemented by providing separate, independently mountable starter units that can be selectively installed on the auxiliary gearbox pad. Each starter (electric starter and air turbine starter) has its own mounting interface and can be independently coupled to or decoupled from the common pad, allowing manufacturers to produce the gearbox in a standard configuration and then selectively install one or two starters based on specific application requirements without redesigning the entire gearbox.
3Area of stationary object
If the electric starter is integrated with the auxiliary gearbox, then space is saved, but the starter cannot be independently maintained or replaced
Solution Approach 1:
The electric starter is designed as a separable component that can be independently removed from the auxiliary gearbox assembly. The starter includes its own mounting bracket and coupling mechanism that interfaces with the gearbox pad, allowing the starter to be extracted and replaced without disturbing or damaging the auxiliary gearbox structure. This extraction capability enables independent maintenance and replacement of the starter while preserving the integrity of the gearbox.
4Device complexity
If a common pad is used for both starters, then the configuration is simplified, but torque transmission to both starters must be managed
Solution Approach 1:
The common pad is equipped with dynamic coupling mechanisms that allow torque to be selectively transmitted to either or both starters based on operational requirements. The pad includes engageable interfaces with the electric starter and air turbine starter that can be selectively activated, allowing the system to dynamically switch between single-starter and dual-starter operation modes, and to distribute torque appropriately when both starters are engaged during engine cranking.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables efficient dual-mode starting of turbine engines without gearbox redesign, supports higher torque and electrical power needs, and allows for additional electrical power generation without modifying the existing auxiliary gearbox or generator components.
Implementation Method 1
the mounting member may comprise a damping member
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A system for starting a turbine engine (100) is provided. The system may comprise a gearbox (114), a first starter (328), and a second starter (330). The gearbox (114) may have a gearbox input shaft (634). The gearbox input shaft (634) may be rotationally coupled to a spool of the turbine engine (100). The first starter (328) may have a first-starter shaft (638). The second starter (330) may have a second-starter shaft (638). The second-starter shaft (638) may be coaxial with the first-starter shaft (638). The first starter (328) and the second starter (330) may each be coupled to the gearbox input shaft (634) independently of one another.