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Magnetic slot wedges are usually installed in open slot high-voltage induction machines. They reduce the no load losses and the magnetization current. Additionally, the leakage inductance increases. However, machines and the slot wedges are getting frequently damaged with a decreasing maintenance interval. The usage of magnetic slot wedges leads to unknown effects. It is possible, that direct magnetic forces or indirect forces, caused by the deformation of the stator or stator teeth during operation, results in the damage of the slots wedges. The purpose of this paper is to fully understand the influence of the magnetic slot wedges and the intrinsic effects.

A finite element model of the affected machine is verified with current and torque values from the data sheet of the affected machine. Three types of forces, which are working on the slot wedges, are considered and compared.

There are direct forces working on the slot wedges. The origin of this forces and a coherence between this forces and the slot number relationship, between stator and rotor slots is shown as well as reasons for the damage to the slot wedges.

There are investigations about the influence of the behaviour of an induction machine by magnetic slot wedges. This investigations consider the influence on the network models of such machines. The paper at hand deals with the intrinsic effects caused by the slot wedges and its consequences.

The purpose of this paper is to describe the derivation of an adjustment directive for the non‐linear and coupled forces of a high‐comfort elevator guiding system based on so‐called electromagnetic ω‐actuators.

The derivation of the adjustment directive contains a coordinate transformation from local forces and torques to global quantities.

It is demonstrated that the derived system is able to operate the guiding system of the elevator car. Measurement results show a well running system in face of several mutual influences on the actuating forces.

The results presented offer the opportunity to increase the riding comfort and decrease the deterioration of high‐speed elevator systems. It is possible to apply the proposed system to ropeless elevators and to conventional elevator systems as well.

The methods developed and proved in this paper grant an effective way to control magnetically levitated systems with complex actuator topologies.

The purpose of this paper is to present the dependence of the level and harmonic structure of the cogging torque in permanent magnet synchronous motors (PMSM) to interlocks and notches in a stator back iron, which are standard methods for stator lamination stacking in mass‐production.

Methods of stacking up the lamination like welding or interlocking are introducing magnetic asymmetries in stator back iron which causes additional harmonic components (AHC). A finite element method and Fast Fourier transform were used to calculate cogging torque harmonic components (HC) with regard to the applied number and positions of interlocks and notches. All simulation results were verified by laboratory tests.

It has been established and proved that technologies for stacking lamination packs cause local saturation peaks in back iron which give rise to additional cogging torque AHC and consequently increase the total cogging torque. It is also shown that the magnetic properties of interlocks cannot be simply considered as air regions but adequate relative permeability of such affected soft magnetic material must be determined to improve the accuracy of FEM calculations.

Considering presented results, it is possible to foresee which AHC will include the cogging torque of mass‐produced PMSMs due to the stator lamination stacking methods. In this way, the optimal stacking method can be selected in order to minimize the effect of AHC.

So far, authors dealing with the cogging torque have not taken into account the influence of the stator lamination stacking method on the level of torque oscillations.