A DVR Control for Compensating Unbalanced Voltage Dips of a DFIG System using Zero Sequence Components

The dynamic voltage restorer (DVR) is an effective protection device for wind turbine generators based on doubly-fed induction generator (DFIG) that is operated under unbalanced voltage dip conditions. The compensating voltages of the DVR depend on the voltage dips and on the influence of the zero sequence component. The zero sequence component results in high insulation costs and asymmetry in terminal voltages. This paper proposes the use of a proportional-resonant controller in stationary reference frames for controlling zero sequence components in the DVR to protect the DFIG during unbalanced voltage dips. To enhance the proposed control method, a comparison is carried out between two cases: with and without using the control of a zero sequence component. Simulation results are presented to verify the effectiveness of the proposed control method by using the Psim simulation program.

[1]  Zhongdong Yin,et al.  Self zero sequence component control of dynamic voltage restorer in systems with different neutral point grounded modes , 2005, 2005 International Power Engineering Conference.

[2]  D Ramirez,et al.  Low-Voltage Ride-Through Capability for Wind Generators Based on Dynamic Voltage Restorers , 2011, IEEE Transactions on Energy Conversion.

[3]  J. Morren,et al.  Ridethrough of wind turbines with doubly-fed induction generator during a voltage dip , 2005, IEEE Transactions on Energy Conversion.

[4]  Lie Xu,et al.  Coordinated Control of DFIG's Rotor and Grid Side Converters During Network Unbalance , 2008, IEEE Transactions on Power Electronics.

[5]  Frede Blaabjerg,et al.  Proportional-resonant controllers and filters for grid-connected voltage-source converters , 2006 .

[6]  J. López,et al.  Wind Turbines Based on Doubly Fed Induction Generator Under Asymmetrical Voltage Dips , 2008, IEEE Transactions on Energy Conversion.

[7]  Stavros A. Papathanassiou,et al.  A review of grid code technical requirements for wind farms , 2009 .

[8]  Lie Xu,et al.  Dynamic Modeling and Control of DFIG-Based Wind Turbines Under Unbalanced Network Conditions , 2007, IEEE Transactions on Power Systems.

[9]  D.M. Vilathgamuwa,et al.  Mitigating Zero Sequence Effects in Dynamic Voltage Restorers , 2007, 2007 IEEE Power Electronics Specialists Conference.

[10]  F.W. Fuchs,et al.  High voltage ride through with FACTS for DFIG based wind turbines , 2009, 2009 13th European Conference on Power Electronics and Applications.

[11]  Math Bollen,et al.  Mitigation of unbalanced voltage dips using static series compensator , 2003, IECON'03. 29th Annual Conference of the IEEE Industrial Electronics Society (IEEE Cat. No.03CH37468).

[12]  Jon Clare,et al.  Doubly fed induction generator using back-to-back PWM converters and its application to variable-speed wind-energy generation , 1996 .

[13]  R. Steele,et al.  Closed-loop power control in CDMA systems , 1996 .