Dynamic Control of the Brushless Doubly Fed Induction Generator Under Unbalanced Operation

The brushless doubly fed induction generator (DFIG) (BDFIG) shows commercial promise for wind power generation because of its lower maintenance needs compared to the widely used DFIG. From power grid codes, installed wind turbines are sometimes required to be capable of operating under unbalanced grid conditions. This paper presents a novel controller for BDFIG-based wind generators operated with asymmetrical voltage supplies. Two synchronous reference frames, the positive and the negative, are introduced for applying a vector control scheme to separately control two sequences arising from the unbalanced voltage. Different control strategies are discussed for reducing the consequent oscillations. It is demonstrated that the proposed controller shows a significant performance improvement over the conventional controller and is effective to cope with potentially unbalanced conditions.

[1]  S. Arnalte,et al.  Direct Power Control Applied to Doubly Fed Induction Generator Under Unbalanced Grid Voltage Conditions , 2008, IEEE Transactions on Power Electronics.

[2]  Math Bollen.  IEEE Richard Harold Kaufmann Award Call for Nominations , 2002 .

[3]  Javier Poza,et al.  Unified reference frame dq model of the brushless doubly fed machine , 2006 .

[4]  Thomas A. Lipo,et al.  New Control Method Including State Observer of Voltage Unbalance for Grid Voltage-Source Converters , 2010, IEEE Transactions on Industrial Electronics.

[5]  Jeong-Ik Jang,et al.  Control of Back-to-Back PWM Converters for DFIG Wind Turbine Systems under Unbalanced Grid Voltage , 2007, 2007 IEEE International Symposium on Industrial Electronics.

[6]  Joseph Warrington,et al.  Practical deployment of the Brushless Doubly-Fed Machine in a medium scale wind turbine , 2009, 2009 International Conference on Power Electronics and Drive Systems (PEDS).

[7]  Tomonobu Senjyu,et al.  Output power leveling of wind turbine Generator for all operating regions by pitch angle control , 2006 .

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

[9]  Marco Liserre,et al.  Overview of Multi-MW Wind Turbines and Wind Parks , 2011, IEEE Transactions on Industrial Electronics.

[10]  Peter Tavner,et al.  Using an FMEA method to compare prospective wind turbine design reliabilities , 2010 .

[11]  L. Burbridge,et al.  Self-cascaded machine: a low-speed motor or high frequency brushless alternator , 1970 .

[12]  Ge Global.  Integrating Large Wind Farms Into Weak Power Grids With Long Transmission Lines , 2007 .

[13]  P. Cartwright,et al.  VSC transmission operating under unbalanced AC conditions - analysis and control design , 2005, IEEE Transactions on Power Delivery.

[14]  Nicholas Jenkins,et al.  Integration of wind turbines on weak rural networks , 1996 .

[15]  Eduard Muljadi,et al.  Understanding the unbalanced-voltage problem in wind turbine generation , 1999, Conference Record of the 1999 IEEE Industry Applications Conference. Thirty-Forth IAS Annual Meeting (Cat. No.99CH36370).

[16]  Ned Mohan,et al.  Control of a doubly-fed induction wind generator under unbalanced grid voltage conditions , 2005 .

[17]  Shiyi Shao,et al.  Stator-Flux-Oriented Vector Control for Brushless Doubly Fed Induction Generator , 2009, IEEE Transactions on Industrial Electronics.

[18]  G. Tapia,et al.  Modeling and control of a wind turbine driven doubly fed induction generator , 2003 .

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

[20]  Lie Xu,et al.  Enhanced Control and Operation of DFIG-Based Wind Farms During Network Unbalance , 2008, IEEE Transactions on Energy Conversion.

[21]  Lie Xu,et al.  Coordinated Control of DFIG and FSIG-Based Wind Farms Under Unbalanced Grid Conditions , 2010, IEEE Transactions on Power Delivery.

[22]  P. C. Roberts,et al.  Performance of the bdfm as a generator and motor , 2005 .

[23]  Antti J. Koivo,et al.  Nonlinear predictive control with application to manipulator with flexible forearm , 1999, IEEE Trans. Ind. Electron..

[24]  Hong-Seok Song,et al.  Dual current control scheme for PWM converter under unbalanced input voltage conditions , 1999, IEEE Trans. Ind. Electron..

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

[26]  Peter Tavner,et al.  Reliability of wind turbine subassemblies , 2009 .

[27]  Yong Liao,et al.  Evaluation of the effects of rotor harmonics in a doubly-fed induction generator with harmonic induced speed ripple , 2003 .

[28]  Malcolm McCulloch,et al.  Control method comparison of doubly fed wind generators connected to the grid by asymmetric transmission lines , 2000 .

[29]  David J. Atkinson,et al.  Combined magnetising flux oriented control of the cascaded doubly-fed induction machine , 2001 .

[30]  H Markiewicz,et al.  Voltage Disturbances Standard EN 50160 - Voltage Characteristics in Public Distribution Systems , 2008 .

[31]  R. W. De Doncker,et al.  Doubly fed induction generator systems for wind turbines , 2002 .

[32]  Barry W. Williams,et al.  Improved Control of DFIG Systems During Network Unbalance Using PI–R Current Regulators , 2009, IEEE Transactions on Industrial Electronics.