Fundamental Frequency Suppression for the Detection of Broken Bar in Induction Motors at Low Slip and Frequency

Abstract

Broken rotor bar (BRB) is one of the most common failures in induction motors (IMs) these days; however, its identification is complicated since the frequencies associated with the fault condition appear near the fundamental frequency component (FFC). This situation gets worse when the IM slip or the operation frequency is low. In these circumstances, the common techniques for condition monitoring may experience troubles in the identification of a faulty condition. By suppressing the FFC, the fault detection is enhanced, allowing the identification of BRB even at low slip conditions. The main contribution of this work consists of the development of a preprocessing technique that estimates the FFC from an optimization point of view. This way, it is possible to remove a single frequency component instead of removing a complete frequency band from the current signals of an IM. Experimentation is performed on an IM operating at two different frequencies and at three different load levels. The proposed methodology is compared with two different approaches and the results show that the use of the proposed methodology allows to enhance the performance delivered by the common methodologies for the detection of BRB in steady state.

Performance Analysis of Axial-Flux Induction Motor with Skewed Rotor

“…By this purpose, three analyses are done with using SMC material for stator, rotor and both of them. Somaloy 700-3P is selected as a SMC material with a density 7.57 g/cm 3 [42].…”

“…Today, more than 40% of the global energy consumption amount is consumed by induction motors and this rate exceeds 70% in the industry [1,2]. Additionally, these motors are key components of many industrial processes, with their reliability, and low cost of maintenance and construction [3,4]. Considering the amount of energy consumed by these motors, it is seen that even a small change in their efficiency will provide significant savings in worldwide energy consumption.…”

Mechanical Fault Diagnostic in PMSM from Only One Current Measurement: A Tacholess Order Tracking Approach

“…The isolation of fault components in currents is more difficult than in vibratory measurement because the signal-to-noise ratio is much lower and the fundamental electrical component is of high amplitude and masks the sought frequencies. One possibility is to remove this fundamental in order to amplify the fault frequencies [ 20 ]. However, the simplest solution is to demodulate the currents in amplitude or in phase.…”

Sensorless Speed Estimation for the Diagnosis of Induction Motors via MCSA. Review and Commercial Devices Analysis

“…This method is mainly applied to detect speed-dependent fault harmonics in the frequency spectrum of stator current [ 18 ], although other magnitudes can also be used (e.g., instantaneous power, reactive power or apparent power [ 19 , 20 , 21 ]). Many research papers, whose main purpose is not localizing the fault harmonic, since they test lab motors with perfectly-known conditions, analyze the expected fault harmonic frequency band assuming that the highest peak of the band will be the fault harmonic [ 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ]. Some other authors use filters as wavelet transform to extract sub-signals related to frequency bands where the harmonic is supposed to be [ 31 , 32 , 33 ].…”