Rotor Blade Health Monitoring via Signal Normalization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing systems fail to accurately predict and detect cracks or fractures in rotor blades or airfoils in real-time, leading to potential hazards and significant monetary losses due to their operation under extreme conditions.
Innovation Solution
A method and system that determine static deflections of rotor blades by normalizing delta times of arrival, removing common factor effects, and generating a reconstruction matrix to identify blade coefficients corresponding to common modes, allowing for real-time monitoring of blade health.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If real-time monitoring of blade health is implemented, then detection accuracy of cracks and fractures is improved, but system complexity increases
Solution Approach 1:
The patent replaces complex mechanical monitoring systems with signal processing methods. By using blade passing signals from existing sensors and applying mathematical transformations (FFT, modal analysis), the system achieves crack detection without adding complex mechanical measurement devices to the blades themselves.
Solution Approach 2:
The patent introduces modal parameters (natural frequencies, mode shapes) as intermediaries between the physical blade state and the detection system. These modal parameters serve as mediators that translate complex blade health information into analyzable signal characteristics, simplifying the overall detection system.
2Measurement precision
If comprehensive monitoring data is collected, then measurement precision is improved, but data processing complexity increases
Solution Approach 1:
The patent extracts only the essential modal parameters (natural frequencies, mode shapes, damping ratios) from the comprehensive blade passing signals. By separating and analyzing only these critical features rather than processing all raw signal data, the system maintains measurement precision while reducing data processing complexity.
Solution Approach 2:
The patent segments the blade passing signals into individual blade contributions and further segments the analysis into modal parameters. This segmentation allows the system to process comprehensive monitoring data by breaking it down into manageable, analyzable components that can be processed independently.
3Reliability
If monitoring system is implemented, then reliability of blade operation is improved, but cost of operation increases
Solution Approach 1:
The patent uses the existing rotational motion of the blades and the already-present vibration signals as the monitoring source. The blades essentially monitor themselves through their own operational characteristics, eliminating the need for external power sources or additional actuators, thereby reducing operational costs while maintaining reliability.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method 200 and a system 10 are presented. The method 200 includes the steps of determining 208 normalized delta times of arrival corresponding to a plurality of blades 12 based upon actual times of arrival corresponding to the plurality of blades 12, and determining 220 static deflections of the plurality of blades 12 by removing effects of one or more common factors from the normalized delta times of arrival corresponding to the plurality of blades 12.