THE PURPOSE. The rapid development of electric transport requires the use an energy-efficient drive in order to increase range runs between battery charges. This, turn, research optimize system based on asynchronous motor with a combined winding. METHODS.. A combination winding is high performance stator consisting two star and delta windings connected parallel. structure mathematical model eng...

Hanne Jussila Concentrated Winding Multiphase Permanent Magnet Machine Design and Electromagnetic Properties – Case Axial Flux Machine Lappeenranta 2009 119 p. Acta Universitatis Lappeenrantaensis 374 Diss. Lappeenranta University of Technology ISBN 978-952-214-882-7, ISBN 978-952-214-883-4 (PDF), ISSN 1456-4491 Concentrated winding permanent magnet machines and their electromagnetic properties...

For hybrid electric vehicles, the batteries and the drive dc link may be at different voltages. The batteries are at low voltage to obtain higher volumetric efficiencies, and the dc link is at higher voltage to have higher efficiency on the motor side. Therefore, a power interface between the batteries and the drive’s dc link is essential. This power interface should handle power flow from batt...

A reliable and accurate diagnosis of inter-turn short circuit faults is a challenging problem in the area of fault diagnosis of electrical machines. The purpose of this challenge is to be more efficient in fault detection and to provide a reliable method with low-cost sensors and simple numerical algorithms which not only detect the occurrence of the fault, but also locate its position in the w...

Conjugate heat transfer problem of a disc winding in a power transformer is studied using commercial CFD software. The study is done for oil flow, temperature distribution, hot spot location and temperature of the winding, for three different cases: first, no oil leakage past the top washer; second, partial leakage due to a 2 mm gap between the top oil guiding washer and cylindrical pressboard;...

This paper presents the influences of winding magneto-motive force (MMF) harmonics on the torque characteristics in surface-mounted permanent magnet vernier (SPMV) machines. Based on the magnetic gearing effects, the armature magnetic field of the SPMV machines is modulated by flux modulation poles (FMPs). In the modulated magnetic field, a working harmonic which corresponds to the number of th...

We study the spectrum of open strings on AdS2 branes in AdS3 in an NS-NS background, using the SL(2, R) WZW model. When the brane carries no fundamental string charge, the open string spectrum is the holomorphic square root of the spectrum of closed strings in AdS3. It contains short and long strings, and is invariant under spectral flow. When the brane carries fundamental string charge, the op...

In many years teaching of Electric Machinery, Electrical Engineering Theory, and Power System Analysis, I found that students have difficulty learning how to calculate transformer parameters. It is even more difficult for them to understand the reason of reducing capacity of short circuit of three windings transformer which has different capacities in each winding. However, the calculation of t...

The computer-aided educational tools have gained popularity in the last years with successful implementation in many areas, including in engineering education. These tools are aimed to help the students for visualization of the concepts and to provide the graphical feedback during the learning process. This paper presents a computer-aided educational tool for induction motors, which is a part o...

This paper investigates the behavior of a vectorcontrolled, fault-tolerant, permanent magnet motor drive system adopting a vertically placed strip winding (VSW) which can limit inter-turn short-circuit (SC) fault current to its rated value regardless of the position in the slot containing the shorted turns. The drives’ dynamic behavior is simulated using a per-phase equivalent circuit model wit...