The electrical machine using induced excitation system is a kind of brushless self-excited machine with low cost and high reliability, the induced excited machine would provide high power density at high-speed. But the low efficiency of the excitation system limits the development of this kind machine. Based on traditional excitation system, an improved construction induced excitation system is...

OF DOCTORAL DISSERTATION HELSINKI UNIVERSITY OF TECHNOLOGY P.O. BOX 1000, FI-02015 TKK http://www.tkk.fi Author Andrej Burakov Name of the dissertation Modelling the unbalanced magnetic pull in eccentric-rotor electrical machines with parallel windings Manuscript submitted 08.06.2007 Manuscript revised 07.10.2007 Date of the defence 25.10.2007 Monograph Article dissertation (summary + original ...

The permanent magnet synchronous machine with an external rotor is the most important device for high performance electrical drive systems in particular for hybrid electric vehicles. With such an application, the machine will operate in a wide speed range and on the other hand with very fast changing loads in both motor and generator operational modes. The paper discusses finite element analyse...

This paper presents a topology for the brushless operation of wound-rotor synchronous machine based on subharmonic excitation technique by using two sets multi-pole windings armature as well rotor. The consist four-pole three-phase main winding and two-pole single-phase additional winding, responsible generation fundamental components magnetomotive force (MMF), respectively. rotor contains fiel...

induction motor especially the squirrel cage type of this motor plays important role in industry. according to the application type, this motor place against various stresses that are caused failure in the motor. the most common failure is related to the stator winding. among these failures are turn-to-turn, coil-to-coil and phase to phase faults. flow the high current do to the induction resul...

Overvoltage distribution along the transformer winding must be uniform to certify the safety of the operation of the power transformer. Influence of the parameters variation on the impulse voltage distribution (IVD) in disk winding transformer is going to be analyzed which hasn’t been analyzed on this type of winding in the previous papers. In this research, a transformer with disk winding and ...

According to star graph and winding distribution, MMFs of three kinds 12-slot/10-pole multi-phase multi-layer layout are analyzed by the improved function method. Analysis results show that can suppress even order (12n ± 1) harmonics, thereby reducing eddy-current loss in PMs. Based on unfolded LPMSM model, rotor MMF, air gap flux density, no-load back-EMF analytical permeance method, which is ...

Magnetic gear and magnetic-geared machine (MGM) are the potential solutions in electric vehicles (EVs) powertrains for inherent high efficiency mechanical simplification. However, torque density issue of MGM greatly limits its industrial application. To enhance performance MGM, a torque-enhanced with dual-series-winding design approach proposed. The key merits proposed to achieve space utilizat...

Power system overvoltages due to switching, lightning and other disturbances are the main problem for designers of the power transformers. Once some frequencies of the incoming surges match with some of the natural frequencies of transformer winding, the resonance phenomenon is expected in transformer winding. The resonant overvoltages may destroy the insulation between turns and cause to insul...