A composite passive damping method of the LLCL-filter based grid-tied inverter

This paper investigates the maximum and the minimum gain of the proportional resonant based grid current controller for a grid-tied inverter with a passive damped high-order power filter. It is found that the choice of the controller gain is limited to the local maximum amplitude determined by Q-factor around the characteristic frequency of the filter and grid impedance. To obtain the Q-factor of a high-order system, an equivalent circuit analysis method is proposed and illustrated through several classical passive damped LCL- and LLCL-filters. It is shown that both the RC parallel damper that is in parallel with the capacitor of the LCL-filter or with the Lf-Cf resonant circuit of the LLCL-filter, and the RL series damper in series with the grid-side inductor have their own application limits. Thus, a composite passive damped LLCL-filter for the grid-tied inverter is proposed, which can effectively suppress the possible resonance in case that the grid impedance varies in a wide range. Simulation results are good agreement with the theoretical analysis.

[1]  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.

[2]  F. Blaabjerg,et al.  An LLCL Power Filter for Single-Phase Grid-Tied Inverter , 2012, IEEE Transactions on Power Electronics.

[3]  Jian Sun,et al.  Optimal damping of EMI filter input impedance , 2009, 2009 IEEE Energy Conversion Congress and Exposition.

[4]  J L Agorreta,et al.  Modeling and Control of $N$ -Paralleled Grid-Connected Inverters With LCL Filter Coupled Due to Grid Impedance in PV Plants , 2011, IEEE Transactions on Power Electronics.

[5]  Marco Liserre,et al.  Filter-Based Active Damping of Voltage Source Converters With $LCL$ Filter , 2011, IEEE Transactions on Industrial Electronics.

[6]  Manfred Morari,et al.  Explicit Model-Predictive Control of a PWM Inverter With an LCL Filter , 2009, IEEE Transactions on Industrial Electronics.

[7]  Vinod John,et al.  Filter Optimization for Grid Interactive Voltage Source Inverters , 2010, IEEE Transactions on Industrial Electronics.

[8]  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).

[9]  Emilio Olias,et al.  Overview of the state of technique for PV inverters used in low voltage grid-connected PV systems: Inverters below 10 kW , 2009 .

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

[11]  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.

[12]  Marco Liserre,et al.  Grid-Filter Design for a Multimegawatt Medium-Voltage Voltage-Source Inverter , 2011, IEEE Transactions on Industrial Electronics.

[13]  Zhihong Ye,et al.  Output filter design for a grid-interconnected three-phase inverter , 2003, IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03..

[14]  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).

[15]  P. Mattavelli,et al.  Analysis of Multisampled Current Control for Active Filters , 2007, IEEE Transactions on Industry Applications.

[16]  Gabriel Garcerá,et al.  An Adaptive Robust Predictive Current Control for Three-Phase Grid-Connected Inverters , 2011, IEEE Transactions on Industrial Electronics.

[17]  Johann W. Kolar,et al.  Optimal design of LCL harmonic filters for three-phase PFC rectifiers , 2011 .

[18]  Poh Chiang Loh,et al.  Improved one-cycle-control scheme for three-phase active rectifiers with input inductor-capacitor-inductor filters , 2011 .

[19]  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.

[20]  K.H. Ahmed,et al.  Passive Filter Design for Three-Phase Inverter Interfacing in Distributed Generation , 2007, 2007 Compatibility in Power Electronics.

[21]  Friedrich Wilhelm Fuchs,et al.  PI state space current control of grid- connected PWM converters with LCL filters , 2009, 2009 IEEE Energy Conversion Congress and Exposition.