A unified active damping control for single-phase differential mode buck inverter with LCL-filter

The single-phase differential mode buck inverter is recently introduced with a differential mode for power transfer and a common mode for actively decoupling the second-order power oscillation. However, it is limited to islanded applications with an LC filter. This paper addresses the stability and control of a grid-connected differential mode buck inverter with an LCL filter. A generalized small-signal model of the inverter is built first with the averaged switching model. It is shown that the LCL filter resonance merely occurs in the differential mode, while an LC filter resonance exists in the common mode, provided that the filter parameters of the two bridges are kept the same. A unified active damping control approach is then proposed for stabilizing the inverter and improving the transient performance under a wide range of grid impedance. Lastly, experimental tests are carried out and the results confirm the effectiveness of the theoretical analysis and proposed control approach.

[1]  Frede Blaabjerg,et al.  Virtual RC Damping of LCL-Filtered Voltage Source Converters With Extended Selective Harmonic Compensation , 2015, IEEE Transactions on Power Electronics.

[2]  Marco Liserre,et al.  Systematic Design of the Lead-Lag Network Method for Active Damping in LCL-Filter Based Three Phase Converters , 2014, IEEE Transactions on Industrial Informatics.

[3]  Siew-Chong Tan,et al.  Mitigation of Low-Frequency Current Ripple in Fuel-Cell Inverter Systems Through Waveform Control , 2013, IEEE Transactions on Power Electronics.

[4]  V. Blasko,et al.  A new mathematical model and control of a three-phase AC-DC voltage source converter , 1997 .

[5]  Jun-Ichi Itoh,et al.  A Novel Single-Phase Buck PFC AC–DC Converter With Power Decoupling Capability Using an Active Buffer , 2014, IEEE Transactions on Industry Applications.

[6]  N. Vazquez,et al.  Analysis and experimental study of the buck, boost and buck-boost inverters , 1999, 30th Annual IEEE Power Electronics Specialists Conference. Record. (Cat. No.99CH36321).

[7]  I. Barbi,et al.  A boost DC-AC converter: operation, analysis, control and experimentation , 1995, Proceedings of IECON '95 - 21st Annual Conference on IEEE Industrial Electronics.

[8]  Rui Li,et al.  Influence of Delay on System Stability and Delay Optimization of Grid-Connected Inverters With LCL Filter , 2014, IEEE Transactions on Industrial Informatics.

[9]  Ioan Serban.  Power Decoupling Method for Single-Phase H-Bridge Inverters With No Additional Power Electronics , 2015, IEEE Transactions on Industrial Electronics.

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

[11]  Mei Su,et al.  An Active Power-Decoupling Method for Single-Phase AC–DC Converters , 2014, IEEE Transactions on Industrial Informatics.

[12]  Ioan Serban.  A novel transistor-less power decoupling solution for single-phase inverters , 2013, IECON 2013 - 39th Annual Conference of the IEEE Industrial Electronics Society.

[13]  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).

[14]  G. Garcera,et al.  Sensitivity Study of the Dynamics of Three-Phase Photovoltaic Inverters With an LCL Grid Filter , 2009, IEEE Transactions on Industrial Electronics.

[15]  Hui Zhao,et al.  Active Power Decoupling for High-Power Single-Phase PWM Rectifiers , 2013, IEEE Transactions on Power Electronics.

[16]  V. Vorperian.  Simplified analysis of PWM converters using model of PWM switch. II. Discontinuous conduction mode , 1990 .

[17]  Brendan McGrath,et al.  Regions of Active Damping Control for LCL Filters , 2014 .

[18]  M. Liserre,et al.  A stable three-phase LCL-filter based active rectifier without damping , 2003, 38th IAS Annual Meeting on Conference Record of the Industry Applications Conference, 2003..

[19]  Kamal Al-Haddad,et al.  A review of single-phase improved power quality AC-DC converters , 2003, IEEE Trans. Ind. Electron..

[20]  F. Wang,et al.  A High Power Density Single-Phase PWM Rectifier With Active Ripple Energy Storage , 2010, IEEE Transactions on Power Electronics.

[21]  Xinbo Ruan,et al.  Capacitor-Current-Feedback Active Damping With Reduced Computation Delay for Improving Robustness of LCL-Type Grid-Connected Inverter , 2014, IEEE Transactions on Power Electronics.