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In this investigation we examined the essential oils of three aromatic plants, Zanthoxylum armatum, Juniperus communis, and Dysphania ambrosioides, which are used by the local population of the western Himalayan region for medicinal purposes. These plants were studied for their antifungal, larvicidal and biting deterrent activities. Additionally, chemical compositions of the oils were determined by GC-MS and their odor evaluated. The main compounds were 2-undecanone (47.7%) and 1,8-cineol (20.5%) from Z. armatum and α-pinene (43.2%) and limonene (34.7%) from J. communis. p-Cymene (36.3%) and ascardiole (31.2%) were found as the main components of D. ambrosioides essential oil. Antifungal activity was evaluated against three Colletotrichum species. Dyspania ambrosioides oil showed the best activity against these strawberry anthracnose causing fungi. It also demonstrated biting deterrent activity against Aedes aegypti similar to DEET as positive control, whereas Z. armatum and J. communis were less effective against Colletotrichum and mosquitoes.

This paper discusses finite element analyses of a skewed permanent magnet synchronous machine (PMSM) with an external rotor regarding the magnetic saliency. Since the machine is fed from a voltage source inverter (VSI), a simulation as close as possible to the regular operational behavior is intended. Therefore, a voltage-driven finite element model with a strong circuit coupling excited with the time-dependent voltages according to the space vectors of the VSI will be applied. This approach directly allows for a comparison of the numerically obtained phase currents with those obtained from measurements. Afterwards, the inductance characteristics depending on the rotor position can be evaluated from the time-dependent phase currents in order to obtain the suitability for a sensorless control algorithm. Index Terms--Finite element analysis, inform method, permanent magnet synchronous machine (PMSM), sensorless control.

This paper presents finite-element analyses of radial magnetic bearings where noneentered rotor positions are considered very efficiently. With an introduction of a reformulated air-gap macro element, distinct stator and rotor models can be used, and remeshing of the air gap is avoided. Therefore, static and dynamic rotor eccentricities can be considered very easily. The force--current relations for a typical design of a radial magnetic bearing with four pole pairs in two orthogonal directions are evaluated with both conventional finite-element models and models based on the eccentric air-gap element. Index Terms--Air-gap element, finite element method, magnetic bearing.

The deformation process of Roebel bars embedded in slots of electrical machines mainly depends on the acting electromagnetic forces inside the current carrying regions and the mechanical preload due to the slot wedge. With this fully coupled electromagnetic-mechanical problem, the behavior is completely different between the two cases of loose and fixed bars. To accurately include both the volume forces inside conducting regions and the surface forces at material boundaries in the coupled analyses, a weak coupled cascade algorithm of electromagnetic and mechanical finite-element calculations can be applied. Moreover, this algorithm allows to describe the transitional state between both fixed and loose bars in dependence of the electrical bar currents in an efficient way. Index Terms--Coupled field problems, electromagnetic coupling, finite-element methods, synchronous generators.

The inverter-fed synchronous transverse flux machine with a permanent magnet excited rotor is well suited for the application with advanced drive systems for electric-driven city buses. The topology of such a machine requires three-dimensional finite element analyses to accurately predict the machine parameters. With regard to the mentioned application, the paper presents the evaluation of the electromagnetic cogging torque and the stray field in the rotor carrier. Both the shear stresses and the distribution of the magnetic flux density influence the choice about possible materials of the rotor carrier. Index Terms--Cogging torque, finite element methods, permanent magnet machines, transverse flux machines.