Hultman, E. 2018. Robotized Production Methods for Special Electric Machines. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1608. 82 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-513-0177-8. A research project on renewable energy conversion from ocean waves to electricity was started at the Division of Electricity at Uppsala Unive...

Two different external-rotor-internal-stator TORUS type axial flux PM machines can be derived based on the direction of the flux. In the first type of the TORUS machine, magnet driven flux enters stator and travels circumferentially along the stator core while in the second type the flux enters the stator and travels axially along the machine axis of rotation. The major differences between the ...

A transient model for an induction machine with stator winding turn faults is derived using reference frame transformation theory. A state-space representation of the dynamic equations, suitable for digital simulation is provided. Steady-state equivalent circuits are derived, from which the sequence components of the line currents can be estimated as a function of fault severity. Experimental r...

An autonomous induction generator (IG) with an asymmetric configuration, in which both the stator and the rotor are single-phase, is often formed when a triple-phase wound rotor loses connection to a winding component while running. The machine still works and is shown to be capable of generating modulated waveforms. Equations can help as an IG design guideline. The first harmonics of the mutua...

The state of degradation of stator groundwall insulation in induction motor results in the state of unbalance in threephase stator current at fundamental frequency. In this investigation, the computer simulation model to determine this state of unbalance is developed. On the basis of park‟s transformation model the unbalanced stator current data in three-phase machine variable („abc‟) form is t...

Voltage sags and voltage interruptions are huge power quality problems for many industries. Voltage sags cause apart from eventual tripping, large torque peaks, which may cause damage to the shaft or equipment connected to the shaft. This paper illustrates how the stator flux in a synchronous machine changes during voltage sags. These changes result in torque peaks. An analytical time dependent...

An improved topology of a low-speed permanent magnet vernier machine called a dual-stator interior permanent magnet vernier machine (DS-IPMVM) is introduced to significantly increase torque density and power factor. Dual-stator is usually adopted in machine design for more torque and the abundant space utilization. Interior spoke-type magnet array in the rotor is designed for magnet flux focusi...

This paper presents the comparison results between two new generator configurations. These generator units are namely a field assisted switched reluctance generator (SRG) and a brushless dc (BLDC) generator. No permanent magnets are used in either unit. The field assisted SR generator consists of two magnetically dependent stator and rotor sets (layers), where each stator set includes twelve sa...

The state of degradation of stator groundwall insulation in induction motor results in the state of unbalance in three-phase stator current at fundamental frequency. In this investigation, the computer simulation model to determine this state of unbalance is developed. On the basis of park’s transformation model the unbalanced stator current data in three-phase machine variable (‘abc’) form is ...