WO2008103946-A2  CHEN C.-L. ET AL.: 'Admittance compensation in current loop control for a grid-tie CTL fuel cell inverter' PROC. IEEE POWER ELECTRONICS SPECIALISTS CONFERENCE 17 June 2007, pages 521 - 523;  PARK S.-Y. ET AL.: 'Current loop control with admittance compensation for a single-phase grid-tie fuel cell power conditioning system' PROC. IEEE APPL. POWER ELECTRON. CONF. 25 February 2007, pages 654 - 660;  LOUGANSKI K.P. AND LAI J.-S.: 'Current phase lead compensation in single-phase PFC boost converters with a reduced switching frequency to line frequency ratio' IEEE TRANS. POWER ELECTRON. vol. 22, no. 1, January 2007, pages 113 - 119;  QIANG ZHANG ET AL.: 'Study on grid connected inverter used in high power wind generation system' PROC. IEEE INDUSTRY APPLICATIONS CONFERENCE vol. 2, October 2006, pages 1053 - 1058;  SESHADRI SIVAKUMAR, PARSONS T., SIVAKUMAR S.C.: 'Modeling, analysis and control of bidirectional power flow in grid connected inverter systems' PROC. IEEE POWER CONVERSION CONFERENCE vol. 3, April 2002, pages 1015 - 1019WO2008103946-A3  LOUGANSKI K.P. AND LAI J.-S.: 'Current phase lead compensation in single-phase PFC boost converters with a reduced switching frequency to line frequency ratio' IEEE TRANS. POWER ELECTRON. vol. 22, no. 1, January 2007, pages 113 - 119, XP011154540;  QIANG ZHANG ET AL.: 'Study on grid connected inverter used in high power wind generation system' PROC. IEEE INDUSTRY APPLICATIONS CONFERENCE vol. 2, October 2006, pages 1053 - 1058, XP008117167;  SESHADRI SIVAKUMAR, PARSONS T., SIVAKUMAR S.C.: 'Modeling, analysis and control of bidirectional power flow in grid connected inverter systems' PROC. IEEE POWER CONVERSION CONFERENCE vol. 3, April 2002, pages 1015 - 1019, XP010590297;  PARK S.-Y. ET AL.: 'Current loop control with admittance compensation for a single-phase grid-tie fuel cell power conditioning system' PROC. IEEE APPL. POWER ELECTRON. CONF. 25 February 2007, pages 654 - 660, XP031085280;  CHEN C.-L. ET AL.: 'Admittance compensation in current loop control for a grid-tie CTL fuel cell inverter' PROC. IEEE POWER ELECTRONICS SPECIALISTS CONFERENCE 17 June 2007, pages 521 - 523, XP008117170;  See also references of EP 2122816A2;  LOUGANSKI K.P. AND LAI J.-S.: "Current phase lead compensation in single-phase PFC boost converters with a reduced switching frequency to line frequency ratio", IEEE TRANS. POWER ELECTRON., vol. 22, no. 1, January 2007 (2007-01-01), pages 113 - 119, XP011154540;  QIANG ZHANG ET AL.: "Study on grid connected inverter used in high power wind generation system", PROC. IEEE INDUSTRY APPLICATIONS CONFERENCE, vol. 2, October 2006 (2006-10-01), pages 1053 - 1058, XP008117167;  SESHADRI SIVAKUMAR, PARSONS T., SIVAKUMAR S.C.: "Modeling, analysis and control of bidirectional power flow in grid connected inverter systems", PROC. IEEE POWER CONVERSION CONFERENCE, vol. 3, April 2002 (2002-04-01), pages 1015 - 1019, XP010590297;  PARK S.-Y. ET AL.: "Current loop control with admittance compensation for a single-phase grid-tie fuel cell power conditioning system", PROC. IEEE APPL. POWER ELECTRON. CONF., 25 February 2007 (2007-02-25), pages 654 - 660, XP031085280;  CHEN C.-L. ET AL.: "Admittance compensation in current loop control for a grid-tie CTL fuel cell inverter", PROC. IEEE POWER ELECTRONICS SPECIALISTS CONFERENCE, 17 June 2007 (2007-06-17), pages 521 - 523, XP008117170;  See also references of EP 2122816A4EP2122816-A2  See references of WO 2008103946A2US8824174-B2  Qiang Zhang, Lewei Qian, Chonwei Zhang and David Cartes. "Study on Grid Connected Inverter Used in High Power Wind Generation System", 2006, IEEE, pp. 1053-1058.;  Louganski et al., "Current phase lead compensation in single-phase PFC boost converters with a reduced switching frequency to line frequency ratio", IEEE 2006.;  Sera et al. "Low-Cost Digital Implementation of Proportional-Resonant Current Controllers for PV Inverter Applications Using Delta Operator", IEEE 2005.;  Konstantin P. Louganski and Jih-Shen Lai, "Current Phase Lead Compensation in Single-Phase PFC Boost Converters with a Reduced Switching Frequency to Line Ratio," IEEE Trans. Power Electron., vol. 22, No. 1, pp. 113-119, Jan. 2007. See abstract; figures 10-13; pp. 262-266.;  Qiang Zhang, Lewei Qian, Chongwei Zhang and D. Cartes, "Study on Grid Connected Inverter Used in High Power Wind Generation System," in Proc. IEEE Industry Applications Conference, vol. 2, pp. 1053-1058, Oct. 2006. See abstract; figures 1-2; pp. 1054-1055.;  Seshadri Sivakumar, Tom Parsons and Shyamala C. Sivakumar, "Modeling, Analysis and Control of Bidirectional Power Flow in Grid Connected Inverter Systems," in Proc. IEEE Power Conversation Conference, vol. 3, pp. 1015-1019, Apr. 2002. See abstract; figures 1a and 1b.;  Sung-Yeul Par, Jih-Sheng Lai, Chien-Liang Chen and Tae-Won Chun, "Current Loop Control with Admittance Compensation for a Single-Phase Grid-Tie Fuel Cell Power Conditioning System," in Proc. IEEE Appl. Power Electron. Conf., pp. 654-660, Feb. 25, 2007. See abstract; figure 1; pp. 655-657.;  Chien-Liang Chen, Sung-Yeul Park, Jih-Sheng Lai and Seung-Ryul Moon, "Admittance Compensation in Current Loop Control for a Grid-Tie LCL Fuel Cell Inverter," in Proc. IEEE Power Electronics Specialists Conference, pp. 520-526, Jun. 17, 2007. See abstract; figure 1; pp. 521-523.;  Sera, et al. "Low-Cost Digital Implementation of Proportional-Resonant Current Controllers for PV Inverter Applications Using Delta Operator", IEEE Industrial Elecronics Society Conf. 2005, 7 pages.