Browse > Article
http://dx.doi.org/10.5370/KIEE.2015.64.5.708

Droop Control Method for Circulating Current Reduction in Parallel Operation of BESS  

Sin, Eun-Suk (Dept. of Electrical Engineering, Myongji University)
Kim, Hyun-Jun (Dept. of Electrical Engineering, Myongji University)
Yang, Won-Mo (Dept. of Electrical Engineering, Myongji University)
Han, Byung-Moon (Dept. of Electrical Engineering, Myongji University)
Publication Information
The Transactions of The Korean Institute of Electrical Engineers / v.64, no.5, 2015 , pp. 708-717 More about this Journal
Abstract
This paper proposes a new reduction scheme of circulating current when two units of BESS (Battery Energy Storage System) are operated in parallel with conventional droop control. In case of using conventional droop, the terminal voltage of each BESS are not equal due to the unequal line impedance, which causes the circulating current. The operation performance of BESS is critically dependant on the circulating current because it increases system losses which causes the increasement of required system rating. This paper introduces a new reduction scheme of circulating current in which the terminal voltage difference of each BESS is compensated by adding feed-forward path of line voltage drop to the droop control. The feasibility of proposed scheme was first verified by computer simulations with PSCAD/EMTDC software. After then a hardware prototype with 5kW rating was built in the lab and many experiments were carried out. The experimental results were compared with the simulation results to confirm the feasibility of proposed scheme. Two parallel operating BESS with proposed scheme shows more accurate performance to suppress the circulating current than those with the conventional droop control.
Keywords
BESS (Battery Energy Storage System); Droop Control; Line Impedance; Circulating Current; Feed-forward Loop.;
Citations & Related Records
연도 인용수 순위
  • Reference
1 K. S. Paprika, M. Ozdemir and M. T. Aydemir “Active and reactive power sharing and frequency restoration in a distributed power system consisting of two UPS units,” Electrical Power and Energy Systems , Vol. 31, pp. 220-226, 2009.   DOI   ScienceOn
2 K. D. Brabandere, B. Bolsens, J. V. Keybus, A. Woyte, J. Driesen, and R. A. Belmans, “Voltage and frequency droop control method for parallel inverters,” IEEE Trans. on Power Electron., Vol. 22, No. 4, pp. 1107–1115, 2007.   DOI   ScienceOn
3 J. M. Guerrero, L. G. de Vicuña, J. Matas, M. Castilla, and J. Miret, "A wireless controller to enhance dynamic performance of parallel inverters in distributed generation systems," IEEE Trans. Power Electron., vol. 19, no. 5, pp. 1205-1213, Sep. 2004.   DOI   ScienceOn
4 N. Pogaku, M. Prodanovic, and T. Green, "Modeling, analysis and testing of autonomous operation of an inverter-based microgrid," IEEE Trans. Power Electron., vol. 22, no. 2, pp. 613-625, Mar. 2007.   DOI
5 A. Tuladhar. H. Jin. T. Unger. and K. Mauch. “Parallel Operation of single-phase inverter modules with no control interconnections,” in IEEE APEC, pp. 94-100, 1997.
6 J. M. Guerrero, L. G. de Vicuña, J. Matas, M. Castilla, and J. Miret, "Output impedance design of parallel-connected UPS inverters with wireless load-sharing control," IEEE Trans. Ind. Electron., vol. 52, no. 4, pp. 1126-1135, Aug. 2005.   DOI   ScienceOn
7 Y. W. Li and C. N. Kao, “An accurate power control strategy for power-electronics-interfaced distributed generation units operation in a low voltage multibus microgrid,” IEEE Trans. on Power Electron., Vol. 24, No. 12, pp. 2977-2988, 2009.   DOI   ScienceOn
8 K. De Brabandere, B. Bolsens, J. Van den Keybus, A. Woyte, J. Driesen, and R. Belmans, “A voltage and frequency droop control method for parallel inverters,” IEEE Transactions on Power Electronics, vol. 22, no. 4, pp. 1107–115, 2007.   DOI   ScienceOn
9 J. Holtz, W. Lotzkat, and K. H. Werner, "high-power multitransistor inverter uninterruptible power supply system," IEEE Trans. Power Electronic., vol. 3, no. 3, pp. 278-85, Jul. 1988.   DOI   ScienceOn
10 C. T. Lee, C. C. Chu, and P. T. Cheng, "new droop control method for the autonomous operation of distributed energy resource interface converters,"IEEE Trans. Power Electron., vol. 28, no. 4, pp. 1980-993, Apr. 2013.   DOI
11 W. Yao, M. Chen, J. Matas, J. M. Guerrero, and Z. M. Qian, “Design and analysis of the droop control method for parallel inverters considering the impact of the complex impedance on the power sharing,” IEEE Trans. on Ind. Electron., Vol. 58, No. 2, 2011.
12 Hyun-Jun Kim, Yoon-Seok Lee, Jae-Hyuk Kim, Byung-Moon Han. “Coordinated Droop Control for Stand-alone DC Micro-grid”, JEET, vol 9, no. 3,pp.1072-1079,2014
13 M. J. Ryan, W. E. Brumsickle, and R. D. Lorenz, “Control topology options for single-phase UPS inverters”, IEEE Trans. Ind. Appl., vol. 33, no. 2, pp.493-501 1997   DOI   ScienceOn
14 J. M. Guerrero, L. Garc&iacute,a de Vicu&ntilde,a, J. Miret, J. Matas, and M. Castilla, “Integral control technique for single-phase UPS inverter”, Proc. IEEE ISIE',02, pp.1043 -1048 2002
15 J. M. Guerrero, L. Garc&iacute,a de Vicu&ntilde,a, J. Miret, J. Matas, and M. Castilla, “A nonlinear feed-forward control technique for single-phase UPS inverters”, Proc. IEEE IECON',02, pp.257 -261 2002