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Design and Application of a Fault Detection Method Based on Adaptive Filters and Rotational Speed Estimation for an Electro-Hydrostatic Actuator
Published on: October 28, 2022
Signal injection as a fault detection technique
Jordi Cusidó1, Luis Romeral, Juan Antonio Ortega
1MCIA Research Group, Universitat Politècnica de Catalunya, C. Colom 1, Terrassa, 08222 Catalunya, Spain. jordi.cusido@upc.edu
Sensors (Basel, Switzerland)
|December 14, 2011
Summary
This study introduces a novel voltage injection method to improve fault detection in induction motors, especially at low speeds. The technique enhances the analysis of motor current signatures for more reliable diagnostics.
Area of Science:
- Electrical Engineering
- Mechanical Engineering
- Signal Processing
Background:
- Motor Current Signature Analysis (MCSA) is standard for induction motor fault detection.
- MCSA faces challenges with low speed/torque due to harmonic proximity and low amplitudes.
- Existing methods like double frequency tests and signal injection have specific applications.
Purpose of the Study:
- To propose a new method for enhancing induction motor fault detection.
- To overcome limitations of MCSA at low speeds and low torques.
- To improve the accuracy and reliability of motor diagnostics.
Main Methods:
- Injecting an additional voltage at a frequency different from the fundamental.
- Analyzing the resulting harmonics around new frequencies formed by frequency composition.
- Utilizing spectral analysis of stator current.
Main Results:
- The proposed method generates new spectral components.
- These new components are distinct and potentially easier to detect than traditional MCSA harmonics.
- Improved signal-to-noise ratio for fault-related harmonics is anticipated.
Conclusions:
- The novel voltage injection technique offers a promising alternative for MCSA.
- This method can significantly improve fault detection capabilities in induction motors under challenging conditions.
- Further research can validate and optimize this approach for industrial applications.
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