Dual sequence current controller without current sequence decomposition implemented on DSRF for unbalanced grid voltage conditions

Dual sequence current control is the key technique for grid-connected voltage source converter to ensure the performance or fulfill grid requirement under unbalanced grid voltage conditions. In this paper, after reviewing and analyzing the existing dual sequence current controller (DSCC), a simple DSCC is proposed based on double synchronous reference frame (DSRF) without the need of current sequence decomposition. The positive-sequence current is controlled in the positive SRF with a PI controller, while the negative-sequence current is controlled in the negative SRF only with an integrator controller. To avoid the ineffectiveness of the inductor current feed-forward (ICFF) decoupling technique in DSRF, only the decoupling components in the positive SRF is performed. This ensures the same performance with the conventional current controller under normal grid voltage conditions. Further, a new decoupling technique with reference current feed-forward can be optionally employed to provide decouple effect for both positive-sequence and negative-sequence current control. Simulation results will demonstrate the validity of the proposed DSCC.

[1]  M. Liserre,et al.  Multiple harmonics control for three-phase grid converter systems with the use of PI-RES current controller in a rotating frame , 2006, IEEE Transactions on Power Electronics.

[2]  Eduardo P. Wiechmann,et al.  Complex state-space modeling and nonlinear control of active front-end converters , 2005, IEEE Transactions on Industrial Electronics.

[3]  Dehong Xu,et al.  DC-Voltage Fluctuation Elimination Through a DC-Capacitor Current Control for DFIG Converters Under Unbalanced Grid Voltage Conditions , 2013, IEEE Transactions on Power Electronics.

[4]  Marco Liserre,et al.  Grid Converters for Photovoltaic and Wind Power Systems , 2011 .

[5]  Thomas A. Lipo,et al.  A control method in dq synchronous frame for PWM boost rectifier under generalized unbalanced operating conditions , 2002, 2002 IEEE 33rd Annual IEEE Power Electronics Specialists Conference. Proceedings (Cat. No.02CH37289).

[6]  Lie Xu,et al.  Model-Based Predictive Direct Power Control of Doubly Fed Induction Generators , 2010, IEEE Transactions on Power Electronics.

[7]  H. Stemmler,et al.  Stationary frame generalized integrators for current control of active power filters with zero steady state error for current harmonics of concern under unbalanced and distorted operation conditions , 2000, Conference Record of the 2000 IEEE Industry Applications Conference. Thirty-Fifth IAS Annual Meeting and World Conference on Industrial Applications of Electrical Energy (Cat. No.00CH37129).

[8]  Jan T. Bialasiewicz,et al.  Power-Electronic Systems for the Grid Integration of Renewable Energy Sources: A Survey , 2006, IEEE Transactions on Industrial Electronics.

[9]  T Rushi Santhosh Singh,et al.  Energy Management and Power Control of a Hybrid Active Wind Generator for Distributed Power Generation and Grid Integration , 2016 .

[10]  J.W. Kolar,et al.  A Modified Direct Power Control Strategy Allowing the Connection of Three-Phase Inverters to the Grid Through $LCL$ Filters , 2005, IEEE Transactions on Industry Applications.

[11]  J.W. Kolar,et al.  A modified direct power control strategy allowing the connection of three-phase inverter to the grid through LCL filters , 2005, Fourtieth IAS Annual Meeting. Conference Record of the 2005 Industry Applications Conference, 2005..

[12]  Jorge A. Solsona,et al.  Current Controller Based on Reduced Order Generalized Integrators for Distributed Generation Systems , 2012, IEEE Transactions on Industrial Electronics.

[13]  T.A. Lipo,et al.  A control scheme in hybrid synchronous-stationary frame for PWM AC/DC converter under generalized unbalanced operating conditions , 2004, Conference Record of the 2004 IEEE Industry Applications Conference, 2004. 39th IAS Annual Meeting..

[14]  Alejandro G. Yepes,et al.  Evaluation of Techniques for Cross-Coupling Decoupling Between Orthogonal Axes in Double Synchronous Reference Frame Current Control , 2014, IEEE Transactions on Industrial Electronics.

[15]  Math Bollen,et al.  Understanding Power Quality Problems: Voltage Sags and Interruptions , 1999 .

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

[17]  Lennart Harnefors,et al.  Modeling of Three-Phase Dynamic Systems Using Complex Transfer Functions and Transfer Matrices , 2007, IEEE Transactions on Industrial Electronics.

[18]  J George Hwang,et al.  A Single-Input Space Vector for Control of AC–DC Converters Under Generalized Unbalanced Operating Conditions , 2010, IEEE Transactions on Power Electronics.

[19]  F. Briz,et al.  Analysis and design of current regulators using complex vectors , 1997, IAS '97. Conference Record of the 1997 IEEE Industry Applications Conference Thirty-Second IAS Annual Meeting.

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

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

[22]  Francisco D. Freijedo,et al.  Ineffectiveness of orthogonal axes cross-coupling decoupling technique in dual sequence current control , 2013, 2013 IEEE Energy Conversion Congress and Exposition.

[23]  Sergio Vazquez,et al.  A Model-Based Direct Power Control for Three-Phase Power Converters , 2008, IEEE Transactions on Industrial Electronics.

[24]  M. Liserre,et al.  Evaluation of Current Controllers for Distributed Power Generation Systems , 2009, IEEE Transactions on Power Electronics.

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

[26]  P. Rodriguez,et al.  Enhanced Decoupled Double Synchronous Reference Frame Current Controller for Unbalanced Grid-Voltage Conditions , 2012, IEEE Transactions on Power Electronics.