The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A non-destructive method to analyze stator core faults on induction motors is presented and developed in the present work. It allows generating entirely reversible faults of different magnitudes. The quantification of fault severity was performed through the stator core interlaminar insulation test and through no-load test. The obtained experimental results show the feasibility of the method and the...
In the literature the effects caused by a single or several adjacently broken rotor bars, or a broken end ring are thoroughly investigated. The phenomenon of various non-adjacently broken rotor bars has not been studied, so far. Since non-adjacently broken rotor bars may give rise to fault signatures which are not directly related with the fault extent, it is important to understand the nature of...
This paper contains summary information on Diacs technology principles comprising the following subjects: power transformers on-line testing and defects location procedure; on-line diagnostic technology and data analysis; examples of test results. Possible failure scenarios are observed here, as well as general tools available for power transformer life assessment. Specific technology of Diagnostic...
Multiple motors connected to a single closed-loop inverter drive is a common type of drive topology which has wide application in steel processing industry, electric railway systems and electric vehicles. But condition monitoring for this type of drive configuration remains largely unexplored. This paper proposes a new method to detect the stator turn-to-turn fault in a multiple-motor drive system...
A new strategy for monitoring the condition of adjustable speed induction machine drive systems is presented in this paper. The main concept of the new method is to use the inverter to perform off-line tests for quality assessment of the vulnerable components in the inverter, cable, and induction motor automatically, whenever the motor is stopped. This new approach is suitable for monitoring system...
There are various methods to determine the efficiency of three phase induction machines. But all of them have in common that they are too inaccurate or they are impracticable. In this paper the machine efficiency will be derived from start up data. For that purpose the time dependence of all stator currents and all stator voltages have to be measured. Normally it isn't possible to mount a speed sensor...
This paper presents and analyzed short circuit failures for permanent magnet synchronous motor (PMSM). The study includes stated state and dynamic condition for experimental test. The stator current is analyzed by means of Hilbert-Huang transform (HHT) and energy spectrum.
This paper deals with the prognosis of gear faults in DC machines using time frequency distribution methods. The proposed method presents future state prediction of the machine faults using Hidden Markov models. Different methods for estimating the parameters of hidden Markov model with limited data are discussed. The proposed method uses Matching Pursuit decomposition and projections of the training...
This paper presents the simulation and experimental results of a 42 V fault-tolerant six-phase induction machine (6PIM) with opened stator phases. The 6PIM has symmetrical 60 degrees displacement winding allowing fault-tolerant modes for an electric power steering (EPS) application. A voltage source inverter (VSI) in closed-loop using a vector control feeds its. The 6PIM model is derived from the...
We report about fault diagnosis experiments to improve the maintenance quality of motor pumps installed on oil rigs. We rely on the data-driven approach to the learning of the fault classes, i.e. supervised learning in pattern recognition. Features are extracted from the vibration signals to detect and diagnose misalignment and mechanical looseness problems. We show the results of automatic pattern...
Different automatic procedures to estimate induction machines parameters, known as self-commissioning, can be found in literature. They usually involve supplying a single phase or two series-connected phases. An ideal machine should present the same behavior at all terminals, while in an actual machine non-idealities alter the response to the signals. Some techniques to state machine condition during...
Intensive research efforts have been focused on the Motor Current Signature Analysis (MCSA) in order to detect rotor condition of induction machines. The interpretation of the single-phase current spectrum provides direct information on the presence of abnormal conditions, while their quantification is an open problem as signature spectral lines depend also on motor load and inertia. Recently the...
Maintenance is an inevitable reality in industry. Maintenance of a system usually involves maintenance of multiple components with multiple failure modes, each of which may require different maintenance policy (i.e., corrective (CM), preventive (PM), or condition based maintenance (CBM)). A maintenance policy may be best for one component and the worst for the other (CM may be best for a very cheap...
The low cost and high reliability of controlled induction motor drives without mechanical speed sensors made them to become more and more attractive. The information on the rotor speed is obtained from measured stator voltages and currents at the motor terminals with replace the sensor (mechanical sensor). Vector controlled drives require estimating the magnitude and spatial orientation of the fundamental...
The paper deals with the operation of a brushless DC drive during the phase commutation. At first, the various switching patterns that can be used to command the inverter are identified. It is demonstrated that the switching patterns are a combination of two basic commutation modes. For each mode, the current transients during the phase commutation are determined as well as two significant commutation-related...
The diagnosis of mechanical anomalies in railway traction system (RTS) have significant importance on traction system safety and reliability, which can avoid train derailment. This paper deals with torsional vibration assessment in mechanical transmission of RTS by a non-invasive technique. The previous studies on an elementary gearbox-based electromechanical system have shown that the influence of...
This work reports an actual case of multiple-constraint engineering problem, risen when a suitable inverter control has been planned for Italian High-Frequentation Train drives (Treni Alta Frequentazione - TAF). GTO inverters produced harmful harmonic torques in the motor, and harmful harmonic interference with the signal-repetition system. Since switching frequencies should be moved up to solve the...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.