Deregulierung und Sicherheit in der Energieversorgung

Ohne Zusammenfassung     

30 Jahre EXACT-Bauelementesystem

Ohne Zusammenfassung     

Konvergenz der Kommunikationsnetze zu Multiservice-Netzen

The rapid progress in the convergence of communication networks (fixed and mobile networks with data networks) to multi service networks has an impact on the principles of the traditional switching technologies. Future requirements will also have to be fulfilled through service-convergence (bundling of individual services to new services) regardless of organizational or technical boundaries. Requirements in the information- and communication-business all the way to technical network aspects are to be faced. Based on developments in microelectronics, two converging evolutions by packet-oriented technologies (within the network and at the edge of the network) are now taking place. Starting with the principles of circuit-switching and packet-switching the change in today’s telecommunications world will be discussed. Apart from that emphasis will be put on the distribution of the switching functions within the network, the change of the network’s topology, as well as the influence on the signalling protocols (extensions and new approaches).     

Restrukturierung und Kosteneinsparung bei Versorgungsnetzen

The deregulation of the electricity market results in a forced economic pressure in the sector of transmission and distribution grids. Power systems have to be planned, built and operated under economic conditions. By help of asset management as an instrument of strategic network planning in long term costs can be reduced without affecting the power quality. For an urban distribution network the cost saving potentials which can be achieved by restructuring are shown.     

Analyse eines neuen Stromrichter- und Flussregelkonzepts zur Realisierung hochdynamischer Asynchronmaschinenantriebe mit extrem weitem Feldschwächbereich

The paper presents an inverter concept for the realization of an induction machine drive with an extremely wide constant power range. The stator winding of the induction machine is split up into two isolated and quasi-bifilar wound three-phase winding systems. The series operation of the two winding sets provides very high torque at low stator frequencies while keeping the machine terminal and the inverter DC link current relatively low. However, due to the high number of turns field weakening is necessary at low frequencies (approximately at 50% of rated speed) already. Nevertheless, with the help of an electronic transition from series to parallel stator winding arrangement the machine flux can be restored to its nominal value as given for rated machine speed. Consequently, the break-down torque is increased by a factor of 4 which gives the basis for a high maximum speed with constant machine power.     

Die Einordnung der Elektrizitätswirtschaft in den Umweltbereich

The following text gives an overview of the development of SO₂-, NO_x- and CO₂-emissions in different European countries due to the electricity generation. Beyond that means of CO₂-reduction are inspected with special emphasis on the cost.