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transformer winding deformation is common among all sorts of transformer failures. cumulative deformation can eventually burgeon into catastrophic faults and result in entire network outage. it is possible to detect the early signs of faults with
frequency response analysis (fra) is a powerful diagnostic method in detecting transformer winding deformation, which is difficult to detect by conventional measurements. fra relies on the fact that transformer windings can be modelled as a network of capacitance, resistance, self-inductance and mutual inductance; the values of these parameters are altered when a fault occurs on the winding, and hence the frequency response of the winding will change accordingly. this method presently suffers a drawback due to the difficulties in result interpretation. therefore, a reliable diagnostic method, which will enable inexperienced engineers to interpret the results, is needed. many papers have been published on fra techniques, however none of them described the fundamental studies of fra measurements on the basic electrical components. thus, this study is aimed at investigating the fra results produced from various basic electrical circuits, which consist of simple inductors, capacitors and resistors. it is hoped that these simple fra measurements could be used to interpret the complex fra results from transformer windings.
abstract—transformer power system is one of the most important electrical equipment, winding transformer failure is an important cause of damage and threaten the safe operation of the power grid. through theoretical analysis, we propose a lissajous analysis of transformer voltage / current characteristic analysis method to detect winding faults, while...
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this article provides a comprehensive overview of state-of-the-art techniques for detecting and diagnosing stator winding inter-turn short faults (itsfs) in permanent-magnet synchronous motors (pmsms) for electric vehicles (evs). the review focuses on the following three main categories of diagnostic approaches: motor model-based, signal processing-based, and artificial intelligence (ai)-based fault detection and diagnosis methods. motor model-based methods utilize motor state estimation and motor parameter estimation as the primary strategies for itsf diagnosis. signal processing-based techniques extract fault signatures from motor measured data across time, frequency, or time-frequency domains. in contrast, ai-based methods automatically extract higher-order fault signatures from large volumes of preprocessed data, thereby enhancing the effectiveness of fault diagnosis. the strengths and limitations of each approach are thoroughly examined, providing valuable insights into the advancements in itsf detection and diagnosis techniques for pmsms in ev applications. the emphasis is placed on the application of signal processing methods and deep learning techniques in the diagnosis of itsf in pmsms in ev applications.
discover key insights into motor winding analysis and its role in effective preventative maintenance to enhance reliability.
experimental analyses of faults in winding of transformers and rotating electric machines and use of frequency method sfra (sweep frequency response analysis) for analyse winding fault are presented. article presents experimental analyses of faults in winding of transformers and rotating electric machines. the first part of article deals with the possibilities of diagnostics for windings electrical machines. the second part of article deals use of frequency method sfra (sweep frequency response analysis) for analyse winding fault. finally, the article presents experimental measurements of diagnostics for analysis of the windings in distribution transformer and rotating electric machine. on both of the investigated machines is analyzed internal winding fault.
multi-level stator winding failure investigation on the insulation material for industrial induction motor at its incipient stage can achieve tremendous energy savings, minimize maintenance costs, and enhance the operational life. early detection has the main advantage of preventing motor failure, which gradually leads to catastrophic or complete shutdown. in this paper, the multi-level stator winding failure of an industrial induction motor in the numerical model was designed and implemented using finite-element analysis (fea). since multi-level stator winding failure constitutes substantial time and frequency domains, the signature from the motor is analysed employing a time-frequency-based technique using wavelets. early detection of the multi-level stator winding failures uses signatures from the experimental setup of both healthy and faulty motors by combining both modular and virtual instruments. fea results were then validated under the same operating conditions using an experimental setup. it has been observed that the results obtained from the fea are in good agreement with the experimental setup. the frequency component variation in the sensor frequency response for fault conditions at various severity levels suggests multiple frequency bands. when the motor was under the influence of a 50% stator turn-turn fault, a similar frequency band between 700-800 hz was observed. as a result, the proposed research was accurate, with a correlation factor of 0.96.
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winding varnishing is one of the most critical parts of the electric motor rewind process. discover what makes them so important and the main ways they're done.
at present, the detection of transformer winding deformation faults is carried out in an offline state, which requires the transformer to cooperate with the implementation of planned power outages, or it takes place after the sudden failure of the ...
this guide provides an introduction to transformer winding resistance test methods and procedures. photo: testguy winding resistance measurements are an important diagnostic tool for assessing potential damage to transformers caused by factors such as poor design, assembly, handling, unfavorable environments, overloading, or inadequate maintenance. the primary purpose of this test is to identify significant differences between windings and detect any open connections. measuring the resistanc...
while there are parallels to general purpose wire tests, the electrical test requirements of winding wire for can significantly vary.
answer: to check out the burnt winding in a motor or generator, first of all we try to smell the burnt coils, of varnish and paper insulation smell, and check for the continuity of each set of the winding coils, if no continuity found come to a conclusion that winding coils are open circuited. an...
as a key equipment in the power system, the stable operation of transformers is crucial to the safety of the power grid. however, transformers may cause deformation of the windings for various reasons during testing, transportation and operation, which in turn affects their performance. in this paper, we will analyze the causes and effects of transformer winding deformation, and discuss effective detection techniques.
the winding factor is an operand in order to consider the effect of winding distribution and chording on the spatial distribution of the magnetic field in the air gap of synchronous and induction machines. the sinusoidal functions for winding factor calculation presented in literature are not defined and valid for every irregular winding, e.g., single-layer fractional-slot, combined star-delta, multilayer (greater than two), and asymmetrical windings. although the summation of induced voltage phasors (star of slots) is the most accurate method, asymmetrical windings require to be decomposed in symmetrical components. in this paper, in addition to deriving the symmetrical components for asymmetrical multiphase windings, the analytical formulation is presented to relate the harmonic content of winding functions to winding factors. the harmonic leakage factor is accurately formulated from the winding function instead of the görges diagram without the need for summing up an infinite number of normalized winding factors quadratically. without restriction of the number of layers and the distribution of the winding, including full-pitch, chorded and fractional-slot symmetrical and asymmetrical windings, the suggested analysis method is validated with the star of slots and sinusoidal functions of distribution and pitch factors, where applicable.
aiming at the problem of lack of training samples and low accuracy in transformer early winding fault diagnosis, this paper proposes a transformer early faul...
filament winding has emerged as the main process for carbon fiber reinforced plastic (cfrp) fabrication, and tension control plays a key role in enhancing the quality of the winding products. with the continuous improvement of product quality and efficiency, the precision of the tension control system is constantly improving. in this paper, a novel tension control method is proposed, which can regulate the fiber tension and transport speed of the winding process by governing the outputs of three different driven rollers (the torque of the unwind roll, the torque of the magnetic powder brake roller, and the speed of the master speed roller) in three levels. the mechanical structures and dynamic models of the driven rollers and idle rollers are established by considering the time-varying features of the roller radius and inertia. moreover, the influence of parameters and speed variation on fiber tension is investigated using the increment model. subsequently, the control method is proposed by applying fiber tension in three levels according to the features of the three driven rollers. an adaptive fuzzy controller is designed for tuning the pid parameters online to control the speed of the master speed roller. simulation is conducted for verifying the performance and stability of the proposed tension control method by comparing with those of the conventional pid control method. the result reveals that the proposed method outperforms the conventional method. finally, an experimental platform is constructed, and the proposed system is applied to a winding machine. the performance and stability of the tension control system are demonstrated via a series of experiments using carbon fiber under different reference speeds and tensions. this paper proposes a novel tension control method to regulate the fiber tension and transport speed.
motor faults and failure can cause disruptions to business operations and lead to loss of productivity and reduced profits. this is why it is important to | plant engineering
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the frequency response analysis (fra) is a effective diagnostic method in monitoring the deformation of transformer winding. this paper uses the current sweep-sequency source as the excitation to replace the voltage source in the traditional method.and the frequency response curves can be drawn from the current signal rather than the voltage signal.it can be judged whether there is deformation in the transform winding by comparing the frequency response curves.the method can realize the on-line monitoring and diagnosis for the transformers whose neutral points is grounded directly. the research background the safety of transform is the necessary condition for power system operation. as the increasing of power system capacity,the short-circuit current will be bigger than before.therefore, transformer will take more risk of winding deformation.
the operation and efficiency of isolated dc-dc converters, critical components in solid-state transformers, are significantly impacted by leakage inductance in high-frequency transformers (hfts). different converters have varying demands regarding leakage inductance, ranging from precise control to minimal inductance. for instance, the performance of bidirectional isolated converters (bidcs) and resonant converters is dependent on leakage inductance for the delivery of power. this study proposed a method for the control of leakage inductance by altering the winding configuration. the technique involved positioning the primary and secondary windings at predetermined heights to increase the separation between some winding turns, and thus, enhance leakage inductance. by not varying the average length of turns in the winding configuration, the proposed method was able to maintain a consistent copper loss. a modified mathematical model has been put forward to determine the leakage inductance effectively and precisely. the viability and accuracy of this method were validated through simulations and experiments using a three-phase hft (3p-hft) in a 3p-bidc. the results showed that the leakage inductance that was calculated using the theoretical model was closely correlated to that of the simulation model, with only a variance of 3.9% and an error of 4.53% from the experimental results.
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i am considering the use of surge testing in a predictive testing program. are any of you conducting surge testing on large numbers of 480v motors? have you experienced faults that could be blamed on the test procedure? have you restarted motors after they have failed a surge test?
filament winding technique is an automated composite fabrication technique, which is mainly used to produce tubular structure such as storage tanks, vessels, missiles and rocket motor cases. in recent 20 years, filament winding technique has developed as a mature fabrication technology, which is depended on various applied factors. filament wound composite product applied fields are also influenced by different favourable factors. in this paper, a proper analysis method is carried out applied factors, which can enhance filament winding technique usage rate. primarily, swot (strength, weakness, opportunity, and threat) analysis of filament winding technique is fully analysed. secondly, all the applied favourable factors were classified and discussed under six categories, which relates the wind energy, building & construction, mass transportation, chemical/corrosion, infrastructure, and militray & defense. finally, applied favourable factors were discussed in details, and conclusion were summarized and highlighted, which can advance filament winding technique and increase filament wound composite product applied fields.