Title :
A Fault Ride-Through Technique of DFIG Wind Turbine Systems Using Dynamic Voltage Restorers
Author :
Ibrahim, Ahmad Osman ; Nguyen, Thanh Hai ; Lee, Dong-Choon ; Kim, Su-Chang
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Waterloo, Waterloo, ON, Canada
Abstract :
This paper proposes a low-voltage ride-through technique of a doubly fed induction generator (DFIG) wind turbine system using a dynamic voltage restorer (DVR). For effective control of the DVR, digital all-pass filters are used for extracting the positive-sequence component from the unbalanced grid voltage since they have the advantages of giving a desired phase shift and no magnitude reduction over conventional low- or high-pass filters. Using the positive-sequence component, the phase angles for the positive- and negative-sequence components of the grid voltage are derived. A control algorithm for the DVR that is dual voltage controllers only is implemented for the two sequence components in the dq synchronous reference frame. In order to achieve the power rating reduction of the DVR, the stator power reference for the DFIG is reduced during faults. In addition, a control scheme of pitch angle system is applied to stabilize the operation of the wind turbine system in the event of grid faults. PSCAD/EMTDC simulations show the effectiveness of the proposed technique and a feasibility of reducing the power rating of DVR for the fault ride-through capability of DFIG. The validity of the proposed control scheme for the DVR has also been verified by experimental results.
Keywords :
all-pass filters; asynchronous generators; high-pass filters; power generation faults; power grids; power system restoration; stators; voltage regulators; wind turbines; DFIG; DVR; digital all-pass filters; doubly fed induction generator; dual voltage controllers; dynamic voltage restorers; fault ride through technique; grid faults; high-pass filters; pitch angle system; positive-sequence component; stator; wind turbine systems; Circuit faults; Power system stability; Rotors; Stators; Voltage control; Voltage fluctuations; Wind turbines; Doubly fed induction generator (DFIG); dynamic voltage restorer (DVR); grid code; pitch angle system; voltage sag; wind power;
Journal_Title :
Energy Conversion, IEEE Transactions on
DOI :
10.1109/TEC.2011.2158102