Bashir Mahdi Ebrahimi

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Mixed-eccentricity (ME) fault diagnosis has not been so far documented for permanent-magnet (PM) synchronous motors (PMSMs). This paper investigates how the static eccentricity (SE), dynamic eccentricity (DE), and ME in three-phase PMSMs can be detected. A novel index for noninvasive diagnosis of these eccentricities is introduced for a faulty PMSM. The(More)
In this paper, a novel index is introduced for static and dynamic eccentricity fault diagnosis in permanent magnet synchronous motors (PMSMs). The proposed index is a linear combination of the energy, shape factor, peak, head angle of the peak, area below the peak, gradient of the peak of the detail signals in wavelet decomposition, and coefficients of the(More)
Broken rotor bars and end-ring are common faults in three-phase squirrel-cage induction motors. These faults reduce the developed toque and increase the speed fluctuations of the motor. Meanwhile, developed unsymmetrical magnetic generates noise and vibration in the motor. Local heat around the broken bars may gradually break the adjacent bars and the motor(More)
In this paper, winding function method (WFM), applied to a faulted synchronous generator, is modified and is used for online diagnosis of mixed eccentricity fault. For the first time, the static and mixed eccentricities are modeled in synchronous generators. A modified winding function (MWF) method introduced here is more precise compared with previous(More)
This paper proposes a competent method for broken bars fault identification in line-start and inverter-fed industrial induction motors. The basis of the proposed method is to determine different frequency bands of the faulty motor current and extract a proper intrinsic mode function (IMF) developed by empirical mode decomposition (EMD). It is analytically(More)
A no-load induction motor under static eccentricity is modeled using time stepping finite element (TSFE) method; current, torque, and speed signals of the motor are obtained by finite element method (FEM) and used for static eccentricity fault diagnosis and analysis. The frequency spectrum analysis of the stator current around fundamental frequency(More)
In this paper, a new analytical method is proposed for Ohmic and core losses calculation in induction motors under broken bar fault. In this method, new coefficients are introduced to consider non-sinusoidal distribution effects of flux density due to bar breakage. Then, core losses of induction motors in this condition are estimated. In order to calculate(More)
In this paper, two-dimensional time-stepping finiteelement (TSFE) method is performed for modeling and analyzing of a salient pole synchronous generator with different degree of dynamic eccentricity (DE) fault. TSFE analysis is used to describe the influence of DE fault on the flux distribution within the generator and no-load voltage profiles at low and(More)
In this paper, the radial and axial forces due to inrush and short circuit currents on both inner and outer surfaces of low voltage (LV) and high voltage (HV) windings are calculated. Static and dynamic aspects of these forces which are related to the variation of forces versus winding height and time are analyzed. Power transformer in the start-up mode and(More)
In this paper, effects of number of rotor slots on the performance of line start interior permanent magnet synchronous motors (LSIPMSMs) are analyzed in details. Magnetic, electrical and mechanical signals of two LSIPMSMs with 28 and 44 rotor slots are calculated, inspected and compared with each other. Influence of the rotor slots on the space harmonics is(More)
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