Abstract:
The conventional collection grids for offshore wind farm
consist of internal AC link comprising of series-parallel connections
of identical wind energy conversion units (WECUs). Each WECU
includes a 60- or 50-Hz power transformer. The power transformers
are replaced by the power converters in this article. The weight
of a power converter is much lower compared to that of a power
transformer of similar characteristics, thus reducing the weight of
the offshore wind farm. Most of the studies being done to design
DC collection grids use the conventional full-bridge voltage source
converter as the topology of power converter. The efficiency of the
wind farm is low due to the switching losses. In this article a cascade
connection of a diode rectifier and an interleaved DC-DC boost converter
is used for the converter topology. The switches duty cycle is
reduced, thus improving the efficiency of the wind farm. The dynamic
model of the proposed power converter is derived, including its control
schemes. Power Simulator (The Powersim, Rockville, USA) and
MATLAB Software (The MathWorks, Natick, Massachusetts, USA)
are used to test the performances of the proposed converter model.
