Crack fault of rotor is one of the most prominent problems faced by magnetic bearing rotor system. In order to improve the safety performance of this kind of machinery, it is necessary to research the vibration characteristics of magnetic bearing cracked rotor system. In this paper, the stiffness model of the crack shaft element was established by the strain energy release rate (SERR) theory. T...

different methods for detecting broken bars in induction motors can be found in literature. many of these methods are based on evaluating special frequency magnitudes in machine signals spectrums. current, power, flux, etc are among these signals. frequencies related to broken rotor fault depend on slip. in industrial environment due to some phenomena - such as load oscillation, other faults an...

To further enhance the early diagnose precision and efficiency for rotor crack under condition of strongly noise, AE signals is applied to extract fault feature of early rotor cracks with the advantages of strong anti-noise ability, clear fault feature. Based on the Pseudo Wigner-Ville Distribution (PWVD), the amplitude and frequency as feature vector are extracted from the AE signal in this pa...

The aim of this paper is to investigate and detect the multiple faults in machines using broken rotor bar and eccentricity fault frequencies techniques. It is proposed that using both current and instantaneous power signals simultaneously, will detect the multiple faults reliably, specifically using broken rotor bar fault frequencies and eccentricity fault frequencies under various load conditi...

This paper discusses a novel method for motor fault detection under varying load conditions. Winding Function Approach (WFA) is used to develop a mathematical model to provide indication references for parameters under different load levels and different fault situations. Broken bar defects reference indexes are developed to assess rotor fault severity based on stator current and rotor speed. S...

A fault diagnosis system based on LabVIEW is researched to analyze the rotating machinery fault. By developing data acquisition, signal analysis, processing and simulation, pattern recognition and fault diagnosis modules, this system can automatically measure and identify the shaft orbit of a rotor and get fault results. A pattern recognition method on the basis of the invariant moment algorith...

The performance of an Indirect Rotor Field-Oriented Control (IRFOC) scheme for Induction Motors (IMs) is strongly dependent on the motor parameters especially, rotor resistance. As such, to ensure high performance drive system, the variation of the rotor resistance due to the temperature increase need to be estimated based on the available terminal variables. However, the algorithm used to esti...

Fault diagnosis of a wind turbine rotor is considered. The faults considered are sensor faults and blades mounted with a pitch offset. A fault at a single blade will result in asymmetries in the rotor, which can be applied for fault diagnosis. The diagnosis is derived by using the multiblade coordinate (MBC) transformation also known as the Coleman transformation together with active fault diag...

A continuing task in engineering is to increase the reliability, availability and safety of technical processes and to achieve these fault diagnosis becomes an advanced supervision tool in the present industries. Vibration in rotating machinery is mostly caused by unbalance, misalignment, shaft crack, mechanical looseness and other malfunctions. The objective of this paper is to propose a model...

This paper presents the implementation of broken rotor bar fault detection in an inverter-fed induction motor using motor current signal analysis (MCSA) and prognosis with fuzzy logic. Recently, inverter-fed induction motors have become very popular because of their adjustable speed drive. They have been used in many vital control applications such as rolling mills, variable speed compressors, ...