Direct Grid Current Control of LCL-Filtered Grid-Connected Inverter Mitigating Grid Voltage Disturbance

A direct grid current control strategy for LCL-filtered grid-connected inverters is proposed in this paper. The conventional current control strategies are analyzed and compared, and then the necessity of direct grid current control is presented to mitigate the grid voltage disturbance. In the proposed control strategy, the virtual resistance based on the capacitance current is used to realize active damping, zero compensation is brought in to enhance the stability, and the proportional resonant (PR) controller under two-phase static coordinate is designed to track the ac reference current as well as to avoid the strong coupling brought by the coordinate transformation. Under the distortion grid voltage, the PR plus harmonic compensator (PR+HC) structure is adopted to restrain the distortion of the grid current. Finally, the proposed control strategy is verified by the experimental results.

[1]  N. Abdel-Rahim,et al.  Modeling and analysis of a feedback control strategy for three-phase voltage-source utility interface systems , 1994, Proceedings of 1994 IEEE Industry Applications Society Annual Meeting.

[2]  F.W. Fuchs,et al.  Active damping of LCL-filter resonance based on virtual resistor for PWM rectifiers — stability analysis with different filter parameters , 2008, 2008 IEEE Power Electronics Specialists Conference.

[3]  Dehong Xu,et al.  A New Current Feedback PR Control Strategy for Grid-Connected VSI with an LCL Filter , 2009, 2009 Twenty-Fourth Annual IEEE Applied Power Electronics Conference and Exposition.

[4]  M. Liserre,et al.  Design and control of an LCL-filter based three-phase active rectifier , 2001, Conference Record of the 2001 IEEE Industry Applications Conference. 36th IAS Annual Meeting (Cat. No.01CH37248).

[5]  Yan Zhou,et al.  Parameter Design of a Two-Current-Loop Controller Used in a Grid-Connected Inverter System With LCL Filter , 2009, IEEE Transactions on Industrial Electronics.

[6]  Donald Grahame Holmes,et al.  Grid current regulation of a three-phase voltage source inverter with an LCL input filter , 2002, 2002 IEEE 33rd Annual IEEE Power Electronics Specialists Conference. Proceedings (Cat. No.02CH37289).

[7]  Frede Blaabjerg,et al.  Overview of Control and Grid Synchronization for Distributed Power Generation Systems , 2006, IEEE Transactions on Industrial Electronics.

[8]  Sewan Choi,et al.  Performance Improvement of LCL-Filter-Based Grid-Connected Inverters Using PQR Power Transformation , 2010, IEEE Transactions on Power Electronics.

[9]  Dehong Xu,et al.  A New Feedback Method for PR Current Control of LCL-Filter-Based Grid-Connected Inverter , 2010, IEEE Transactions on Industrial Electronics.

[10]  D. Cartes,et al.  Study On Grid Connected Inverter Used in High Power Wind Generation System , 2006, Conference Record of the 2006 IEEE Industry Applications Conference Forty-First IAS Annual Meeting.

[11]  A. Chandra,et al.  Simulation and stability analysis of a 100 kW grid connected LCL photovoltaic inverter for industry , 2006, 2006 IEEE Power Engineering Society General Meeting.

[12]  Christian Wessels,et al.  Limitations of Voltage-Oriented PI Current Control of Grid-Connected PWM Rectifiers With $LCL$ Filters , 2009, IEEE Transactions on Industrial Electronics.

[13]  Donald Grahame Holmes,et al.  Frequency domain analysis of three phase linear current regulators , 1999 .

[14]  M. Liserre,et al.  Genetic algorithm-based design of the active damping for an LCL-filter three-phase active rectifier , 2003, IEEE Transactions on Power Electronics.

[15]  M. Liserre,et al.  Stability of photovoltaic and wind turbine grid-connected inverters for a large set of grid impedance values , 2006, IEEE Transactions on Power Electronics.

[16]  Poh Chiang Loh,et al.  Exploring inherent damping characteristic of LCL-filters for three-phase grid-connected voltage source inverters , 2010, 2010 IEEE Energy Conversion Congress and Exposition.

[17]  Johan Driesen,et al.  Model-based generation of low distortion currents in grid-coupled PWM-inverters using an LCL output filter , 2006, IEEE Transactions on Power Electronics.

[18]  Jih-Sheng Lai,et al.  Admittance Compensation in Current Loop Control for a Grid-Tie LCL Fuel Cell Inverter , 2008 .