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Browsing by Subject "frequency converter"

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  • thumbnail.journal.alt
    Item type:Article, Access status: Open Access ,
    Badania elektromechanicznych zespołów napędowych zwałowarki ZGOT
    (Wydawnictwa AGH, 2009) Anuszczyk, Jan; Jabłoński, Mariusz
    Paper presents the results of laboratory and industrial testing of the caterpillar drives of the loading feeder of the spreader ZGOT-15400.120 working in the strip pit Szczerców of the KWB »Bełchatów« Mine. The electromagnetic and electromechanical transient states in the drive systems have been analysed. A new conception of sensorless steering algorithm modification in the CUVC bord controlling of converter has been introdused. After proposed solution the decrease of motors torque oscilations and mechanical vibrations in the low frequencies range of converter work was obtained.
  • thumbnail.journal.alt
    Item type:Article, Access status: Open Access ,
    Cutting investment costs by using a new solution of speed controlled belt conveyer with available medium voltage 6kV-slipring-motors
    (2007) Loose, Bernd; Paetzold, Thomas; Kroschk, Steffen
    Traditional belt conveyors with power over 400 kW in open pit coal mines are usually equipped with 6 kV slipring motors with resistors or liquid starters. The following benefits of speed-controlled belt conveyors: - saving of energy costs thanks to adjustable belt speed control, depending on the belt loading level, - reduction of mechanical wear of cable drums, gears and conveyor belts, - saving of investment costs thanks to decreasing of installed power in connection with extended loading power, - decreasing the amount of stoppages and reduction of repair costs, do not exist in case of traditional belt conveyors. The 6 kV drives, installed by BEA Technische Dienste Lausitz GmbH and Rockwell Automation in Vattenfall Europe Mining AG with existing 6 kV slipring motors, have enabled to cut investment costs significantly. After additional sensors and measure instruments were mounted and tested with 20-year-old DSRCJ 5621-6 slipring motors (produced by VEM Sachsenwerk), these motors have been feeding by PF7000 6 kV Rockwell Automation frequency converter and working (permanent operation) on the 2,5 m belt conveyor station in open pit coal mine Welzow Sud.
  • thumbnail.journal.alt
    Item type:Article, Access status: Open Access ,
    Modernizacja napędów jazdy i śruby skrętu koparek SchRs 4600 w KWB »Bełchatów«. Założenia i projekt techniczny
    (Wydawnictwa AGH, 2009) Matras, Eugeniusz; Reizer, Ryszard; Umiński, Wojciech
    Brown Coal Mine Bełchatów decided to modernize caterpillar and steering drives of SchRs 4600 excavators that have been build by Krupp of Germany in the seventies of 20th century. In the paper a concept and technical solutions that fulfil the aim of modernization are presented. DC motors driving excavator caterpillars are replaced by AC motors. Each AC motor is supplied and controlled by an advanced adjustable frequency converter. Frequency converters DC terminals are connected to the common DC bus. Such a solution makes it possible to control velocity each of the excavator caterpillar and return energy from motors working as generators to motors driving caterpillars while the excavator is turning. Additionally power feedback units are used to return electrical energy to the mains when AC motors work as generators while the excavator goes down the slope. A program logic controller (PLC) is used for control and monitoring of the multi-motor excavator drive system.
  • thumbnail.journal.alt
    Item type:Article, Access status: Open Access ,
    Współpraca przewzbudzonego silnika synchronicznego z przemiennikiem częstotliwości
    (2008) Drabek, Tomasz; Lerch, Tomasz
    W pracy przedstawiono badania symulacyjne współpracy przewzbudzonego jawnobiegunowego silnika synchronicznego z typowym przemiennikiem częstotliwości przeznaczonym do zasilania silników asynchronicznych. Obliczenia zostały przeprowadzone dla stanów dynamicznych maszyny synchronicznej o mocy znamionowej 3,2 kW oraz, porównawczo, dla maszyny indukcyjnej o takiej samej mocy znamionowej.