Title :
Reduced cost of reactive power in doubly fed induction generator wind turbine system with optimized grid filter
Author :
Dao Zhou ; Blaabjerg, Frede ; Franke, Tobias ; Tonnes, Michael ; Lau, Mogens
Author_Institution :
Dept. of Energy Technol., Aalborg Univ., Aalborg, Denmark
Abstract :
The modern grid requirement has caused that the wind power system behaves more like conventional rotating generators and it is able to support certain amount of the reactive power. For a typical doubly-fed induction generator wind turbine system, the reactive power can be supported either through the rotor-side converter or the grid-side converter. This paper firstly compares the current ripples and supportive reactive power ranges between the conventional L and optimized LCL filter, if the reactive power is injected from the grid-side converter. Then, the loss distribution is evaluated both for the generator and the wind power converter in terms of the reactive power done by the rotor-side converter or the grid-side converter with various grid filters. Afterwards, the annual energy loss is also estimated based on yearly wind profile. Finally, experimental results of the loss distribution are performed in a down-scaled DFIG system. It is concluded that over-excited reactive power injected from the grid-side converter has lower energy loss per year compared to the overexcited reactive power covered by the rotor-side converter. Furthermore, it is also found that the annual energy loss could even become lower with the optimized filter and thereby more energy production for the wind turbine.
Keywords :
asynchronous generators; optimisation; power convertors; reactive power; wind turbines; doubly fed induction generator wind turbine system; grid filter; grid side converter; loss distribution; reactive power; rotor side converter; wind power converter; wind power system; Generators; Inductance; Iron; Power harmonic filters; Reactive power; Stator windings;
Conference_Titel :
Energy Conversion Congress and Exposition (ECCE), 2014 IEEE
Conference_Location :
Pittsburgh, PA
DOI :
10.1109/ECCE.2014.6953595