Due to the limited space available in vehicles, traction drives with high torque densities are a key objective of machine design in the automotive sector. In order to be able to dispense with a multispeed transmission and still achieve high …

With the increasing use of novel semiconductor technologies such as SiC and GaN in inverter-fed electrical machines, the switching losses of the power electronics can be reduced. However, this leads to steeper voltage gradients, resulting in a …

The vibration and acoustic behavior of electric machines is an important aspect of the design process. A crucial part of the modeling is the correct prediction of the stator’s vibration behavior, characterized by the stator’s eigenfrequencies and …

Partially superconducting direct-drive wind turbine generators with high-temperature superconducting excitation winding enable an increase of the rated unit power, higher efficiency, and a high, adjustable power factor. The high excitation …

The contribution of wind turbines (WTs) to enhance the frequency stability of power systems is traditionally analyzed using commonly applied root mean square (RMS) models. RMS WT models require smaller simulation time steps compared to …

Dieser Beitrag stellt einen elektrodynamischen Wandler vor, der im Vergleich zu konventionellen E‑Maschinen wettbewerbsfähige Betriebseigenschaften aufweist, beliebig skalierbar und kostengünstig herzustellen ist. Der Wandler ist geeignet, in …

Die Prozessleistung bei Werkzeug- und Produktionsmaschinen wird von Hauptantrieben zur Verfügung gestellt, bei denen hauptsächlich feldorientiert betriebene Käfigläufermotoren zum Einsatz kommen. Weist die Leistungs-Drehzahl-Kennlinie eine …

Die Modellierung des strukturdynamischen Verhaltens von elektrischen Maschinen ist herausfordernd. Insbesondere die präzise Modellierung der Dämpfung ist nach dem Stand der Technik nicht möglich. Es werden deshalb häufig experimentelle …

LED lighting uses typically switched mode power supply (SMPS) techniques to generate the appropriate LED voltage and current out of high mains voltages. A variety of SMPS controllers is available on the market for this application. Most of these cont…

In order to replace the lightning impulse test, a very sensitive PD-measurement is required for onsite tests of GIS (CIGRE Joint Working Group 33/23.12 in Electra No 176, 1998). The most sensitive UHF-PD-measurement technique consists of low-noise hi…

The distribution system operator TIWAG-Netz AG operates a 220 kV grid in the alpine region of Tirol. Due to the age of the conductors, the fittings and the pylons (approximately 50 years), the question has arisen as to whether, for parts of…

In February and March 2008 cyclone “Emma” crossed some countries of central Europe and caused severe damages. In very local areas thunderstorms with downbursts were embedded in “Emma” and led to collapses of overhead lines.Downbursts are downward win…

In the last few years, the demand for testing extra-long cables, such as submarine cables has grown rapidly. The existing testing methods have been complemented by a new testing technology called DRT (Differential Resonance Technology). This testing …

To improve personal safety and reduce the environmental impact of electrical power supply, alternative insulation fluids are demanded for large power transformers. With their biodegradability, the fact that they can be produced from renewable resourc…

Dielectric response analysis is an advanced technique, providing information about the insulation condition of the measured test object. It is typically used for power transformers, where the water content in the solid cellulosic insulation can be as…

Due to the high magnetic conductivity of transformer cores, very small direct currents in the electric power grid are sufficient to cause half-cycle saturation of the core. Even minor DC-bias leads to a considerable increase of the noise level and to…

A key and important aspect of future power and energy systems is the integration of renewable and distributed energy resources. In order to develop, test and implement such distributed energy resources appropriate methods, procedures and guidelines a…

The generation of white light by Light Emitting Diodes (LED) is presented. Unlike thermal emitters (e.g. incandescent bulbs) or UV excited fluorescent light-sources (e.g. compact fluorescent bulbs), the emission is in the visible range only, allowing…