3-Phase induction motors are widely used as a source of mechanical power for effective operation and low costs. The abnormalities have to be detected in advance to avoid the motor breakdown and the cost associated restrain of plant production. This work discusses current and flux leakage spectral analysis techniques for the diagnosis of broken rotor bars and shortcircuited turns in induction motor fed from different AC sources.
In spite of recent development of various types of models toward motor faults diagnosis and examining different problems associated with 3-phase induction motors the signal spectral analysis is considered as one of most important approaches. Most of the models from simple equivalent circuit to more complex d-q and a-b-c models and lastly developed hybrid models are provided for the integration of different forms of current and/or voltage unbalance. Generally, techniques that relate to asymmetry identify asymmetrical motor faults.
Frequency converters in many applications feed induction motors. Such applications, which play a major role in industry, are growing at a high rate, allow to use 3-phase induction motor as variable speed applications. This paper proposes application of spectral signature analysis for the detection and diagnosis of abnormal electrical and mechanical conditions, which indicates chosen faults in induction motor fed by frequency converter.
Inhaltsverzeichnis (Table of Contents)
- Abstract
- Thesis objectives
- 1. Introduction
- Thesis plan
- 2. Literature review
- Electrical and mechanical monitoring using MCSA techniques
- Asymmetry Based Techniques
- Other Condition Monitoring Techniques
- Literature Review Summary
- 3. COMMON MOTOR FAULTS
- Rotor Faults
- Short Turn Faults
- Effect of current component on the motor faults caused by varying inductance
- Test Circuit for Faults Simmulation
- 4. Motor Fault Diagnosis Using Signal Signature Analysis
- Motor Current Signature Analysis Using FFT
- Detection of Broken Rotor Bars in Three-Phase Induction Motor Using Fast Fourier Transform
- Detection of stator in-turn short circuit using FFT analyses of current
- Detection of Air Gap Eccentricity Using FFT Signature Analysis
- 5. EXPERIMENTAL STUDY OF STATOR AND ROTOR FAULTS DIAGNOSIS OF A THREE-PHASE INDUCTION MOTOR
- Current Spectral Analysis
- Steps Involved In Motor Fault Diagnosis Using FFT Technique
- 6. DETECTION OF BROKEN ROTOR BAR FAULTS USING FAST FOURIER TRANSFORM (FFT) and LabVIEW program
- Experimental Setup
- System Representation Using LabVIEW Program
- Data Acquisition Parameters
- 7. ANALYSIS AND DISCUSSIONS OF BROKEN BARS FAULT
- No-load Healthy Rotor Fed by an Induction Regulator at 50 Hz
- No-Load Faulty Rotor Fed by an Induction Regulator at 50 Hz
- Loaded Healthy Rotor Fed by an Induction Regulator at 50 Hz
- Loaded faulty rotor from an induction regulator at 50 Hz
- No-Load Healthy Rotor Fed by a Frequency Converter at 40 Hz
- No-Load Faulty Rotor Fed by a Frequency Converter at 40 Hz
- Loaded Healthy Rotor Fed by a Frequency Converter at 40 Hz
- Loaded Faulty Rotor Fed by a Frequency Converter at 40 Hz
- No-Load Healthy Rotor Fed by a Frequency Converter at 50 Hz
- No-Load Faulty Rotor Fed from a Frequency Converter at 50
- Loaded Healthy Rotor Fed by a Frequency Converter at 50 Hz
- Loaded Faulty Rotor Fed by a Frequency Converter at 50 Hz
- No-Load Healthy Rotor Fed from a Frequency Converter at 60 Hz
- No-load faulty rotor fed by a frequency converter at 60 Hz
- Loaded healthy rotor fed by a frequency converter at 60 Hz
- Loaded faulty rotor fed by a frequency converter at 60 Hz
- Discussion of Rotor Fault Analysis
- Motor fed from a voltage regulator at 50 Hz
- Rotor fed from frequency converter 40 Hz
- Rotor fed from frequency converter 50 Hz
- Rotor fed from frequency converter 60 Hz
- Summary
- 8. DIAGNOSIS OF SHORT-CIRCUITED TURNS FAULT IN STATOR WINDINGS USING FFT TECHNIQUE
- ANALYSIS AND DISCUSSIONS SHORT CIRCUIT STATOR FAULT
- No-load healthy stator fed by an induction regulator at 50 Hz
- No-load faulty stator fed by an induction regulator at 50 Hz
- Loaded healthy Stator fed by a Induction regulator at 50 Hz
- Loaded faulty Stator fed by a Induction regulator at 50 Hz
- No-load healthy Stator fed by a frequency converter at 40 Hz
- No-load faulty Stator fed by a frequency converter at 40 Hz
- Loaded healthy Stator fed by a frequency converter at 40 Hz
- Loaded faulty Stator fed by a frequency converter at 40 Hz
- No-load healthy Stator fed by a frequency converter at 50 Hz
- No-load faulty Stator fed by a frequency converter at 50 Hz
- Loaded healthy Stator fed by a frequency converter at 50 Hz
- Loaded faulty Stator fed by a frequency converter at 50 Hz
- No-load healthy Stator fed by a frequency converter at 60 Hz
- No-load faulty Stator fed by a frequency converter at 60 Hz
- Loaded healthy Stator fed by a frequency converter at 60 Hz
- Loaded faulty Stator fed by a frequency converter at 60 Hz
- Discussion of stator diagnosis analysis
- Stator fed from induction regulator 50 Hz
- Stator fed from frequency converter 40 Hz
- Stator fed from frequency converter 50 Hz
- Stator fed from frequency converter 60 Hz
- Summary
- 9. Conclusion
Zielsetzung und Themenschwerpunkte (Objectives and Key Themes)
The primary goal of this thesis is to develop a comprehensive method for diagnosing faults in induction motors fed by frequency converters. This is accomplished through a combination of theoretical analysis, practical experimentation, and data analysis. The research focuses on identifying specific faults, including broken rotor bars and short-circuited turns in the stator windings.
- Utilizing signal signature analysis for fault detection in induction motors.
- Analyzing the impact of frequency converter operation on motor fault detection.
- Implementing a LabVIEW program for data acquisition and analysis of motor faults.
- Investigating the effectiveness of FFT techniques for diagnosing broken rotor bars and stator short circuits.
- Developing a detailed understanding of the spectral characteristics of various motor faults.
Zusammenfassung der Kapitel (Chapter Summaries)
This thesis commences with an introduction to the topic, outlining the research objectives and the organization of the thesis. Chapter 2 delves into a comprehensive review of existing literature on motor fault diagnosis, focusing on various monitoring techniques and methodologies. Chapter 3 provides an overview of common faults encountered in induction motors, with an emphasis on rotor faults and short turn faults.
Chapter 4 explores the utilization of signal signature analysis, specifically using FFT techniques, for detecting various motor faults. The chapter discusses the application of FFT for identifying broken rotor bars, stator short circuits, and air gap eccentricity. Chapter 5 focuses on the experimental study of stator and rotor fault diagnosis in a three-phase induction motor, delving into the methodology employed for current spectral analysis. Chapter 6 details the implementation of a LabVIEW program for detecting broken rotor bar faults utilizing FFT techniques.
Chapter 7 presents a thorough analysis and discussion of the results obtained during the experimental study of broken rotor bar faults, examining the variations in motor behavior under various operating conditions. Finally, Chapter 8 examines the application of FFT techniques for diagnosing short-circuited turns fault in stator windings, analyzing the spectral characteristics of the fault under different operating conditions.
Schlüsselwörter (Keywords)
The primary keywords encompassing the core concepts and research focus of this thesis include induction motor faults, frequency converter, fault diagnosis techniques, signal signature analysis, FFT (Fast Fourier Transform), LabVIEW, broken rotor bars, short-circuited turns, stator faults, rotor faults, spectral analysis, current signature, and motor monitoring.
- Arbeit zitieren
- Hussain Mahdi (Autor:in), 2013, Fault diagnosis of induction motor fed by frequency converter. The signal signature analysis technique, München, GRIN Verlag, https://www.grin.com/document/337221
