The Transactions of the Korean Institute of Power Electronics (전력전자학회논문지)

The Korean Institute of Power Electronics (전력전자학회)
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A Study on LLCL Filter to Reduce Harmonic Current of Grid Connected Power Inverter

계통연계형 인버터의 고조파 전류저감을 위한 LLCL 필터에 관한 연구

  • An, Byoung-Woong (Dept. of Control & Instrumentation Engineering, Korea Nat'l Univ of Transportation) ;
  • Hong, Chang-Pyo (Dept. of Control & Instrumentation Engineering, Korea Nat'l Univ of Transportation) ;
  • Kim, Hag-Wone (Dept. of Control & Instrumentation Engineering, Korea Nat'l Univ of Transportation) ;
  • Cho, Kwan-Yuhl (Dept. of Control & Instrumentation Engineering, Korea Nat'l Univ of Transportation) ;
  • Lim, Byung-Kuk (Dept. of Control & Instrumentation Engineering, Korea Nat'l Univ of Transportation)
  • Received : 2013.09.23
  • Accepted : 2013.12.09
  • Published : 2014.02.20
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Abstract

In this paper, the new LLCL filter is proposed for grid connected three-phase PWM inverter for passive damping. LLCL filter inserts a small inductor in the branch of the capacitor of the traditional LCL filter to compose a series resonant circuit to reduce the switching-frequency component on grid current. Using LLCL filter, the switching-frequency current ripple components can be attenuated much better than the LCL filter, leading to a decrease in the total inductance. However, the resonance phenomena caused by zero impedance from the addition of LC branch in LLCL filter can be a big problem. Resonance phenomena of LLCL filter can be a source of grid system instability, so proper damping methods are required. However, it is difficult to apply a passive damping method in the conventional LLCL filter, because the damping resistor increase impedance of the LC branch. Therefore, switching frequency component of grid current can not much attenuated by low Q of LC series resonance effect. In this paper, a new LLCL filter is proposed to overcome the conventional LLCL filter with passive damping. The validity of the proposed method is proven by simulation and experimental result.

Keywords

References

  1. IEEE std. 519-1992-IEEE Recommended Practices and Requirement for Harmonic Control in Electrical Power Systems-IEEE Industry Applications Society/Power Engineering Socitey.
  2. M. Liserre, F. Blaabjerg, and S. Hansen, "Design and Control of an LCL-filter based Three-phase Active Rectifier," IEEE Trans. On. Ind. Appl., Vol. 41, No. 5, 2005.
  3. Weimin Wu, Yuanbin He, and Frede Blaabjerg, "An LLCL Power Filter for Single-Phase Grid-Tied Inverter," IEEE Trans. on Power Electronics, Vol. 25, No.2, pp. 782-789, Feb. 2012.
  4. W. sun, X. Wu, P. Dai, and J. Zhou, "An Over View of Damping Methods for Three-phases PWM Rectifier," in Proc of IEEE ICIT, Chengdu, China, pp. 1-5, April 21-24, 2008.
  5. P. K. Dahono, "A Control Method for DC-DC Converter that has an LCL output filter based on new virtual capacitor and resistor concept," in Proceedings of PESC'04, pp. 36-42, 2004.
  6. V. Blasko and V. Kaura, "A novel control to actively damp resonance in input LC fulter of a three- phase voltage source converter," IEEE Trans. Ind. Applicat., Vol. 33, Mar.-Apr. 1997.ting, Tampa, Florida, pp. 542-550, Oct. 2006. https://doi.org/10.1109/28.568021
  7. Shiying Tang, Li Peng, Yong Kang, "Active Damping Method Using Grid-Side Current Feedback for Active Power Filters with LCL Filters," Journal of Power Electronics, Vol. 11, No. 3, pp. 311-318, May 2011. https://doi.org/10.6113/JPE.2011.11.3.311
  8. June-Seok Lee, Hae-Gwang Jeong, Kyo-Beum Lee, "Active Damping for Wind Power Systems with LCL Filters Using a DFT," Journal of Power Electronics, Vol. 12, No. 2, pp. 326-331, Mar. 2012. https://doi.org/10.6113/JPE.2012.12.2.326
  9. Byoung-Woong An, Hee-Keun Shin, Hag-Wone Kim, Kwan-Yuhl Cho, Byoung-Moon Han, "Active Damping of LCL filter for Three-phase PWM Inverter without Additional Hardware Sensors," Transactions of the Korean Institute of Power Electronics, Vol. 18, No. 1, pp. 10-17, Feb. 2013. https://doi.org/10.6113/TKPE.2013.18.1.10

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  1. Active Damping of LLCL Filters Using PR Control for Grid-Connected Three-Level T-Type Converters vol.15, pp.3, 2015, https://doi.org/10.6113/JPE.2015.15.3.786