The filter
portion of VLT Low Harmonic Drives has the same working principle as a set of
noise cancelling headphones, where the noise or distortion is measured and a
computer phase signal is imposed to compensate for that noise. VLT Low Harmonic Drives don't merely reduce
or mask current distortion; they attack it at the source by performing real
time analysis and actively imposing currents, as needed, to restore and ensure
the highest possible quality sine waves from the power supply grid. They are well suited for: meeting the
toughest of harmonics recommendations/standards; installations that are
generator-powered, or that have generator back-up power; soft power grids; and
grids with limited excess power capacity. VLT Low Harmonic Drives feature a
modular design meaning that most elements are produced in large scale for cost
effective production - and are individually configured according to the
customer's specific needs to deliver the value of a highly customized quality
drive for the price of a mass produced unit. VLT Low Harmonic Drives cause no increased
winding stress and have no impact on bearing life. They provide the user with a full readout of
the unit performance towards the grid, including a graphical overview of grid
behavior. Where the performance of other
low harmonic technologies depend on the stability of the grid and load or
affect the controlled motor, VLT Low Harmonic Drives continuously regulate the
network and load conditions without affecting the connected motor. VLT Low
Harmonic Drives are the only solution that can cut out the harmonic mitigation
during drive operation and so reduce the energy consumption in cases where the
drives do not need the harmonic reduction (at light loading). The result is
lower power consumption and higher energy efficiency. A unique design uses a ducted
back channel to pass cooling air over heat sinks with minimal air passing
through the electronics area. This allows 85 percent of the heat losses to be
exhausted directly outside of the enclosure, improving reliability and
prolonging life by dramatically reducing temperature rise and contamination of
the electronic components.
For more information: http://www.danfoss.com/North_America/BusinessAreas/DrivesSolutions/Frequency+Drives/VLT+Low+Harmonic+Drive.htm
Danfoss Drives' VLT® Low Harmonic Drive
Article-Danfoss Drives' VLT® Low Harmonic Drive
0 comments
Hide comments