Harmonic Voltage Reduction by using Droop Controller in Inverters Parallel Operation
Subject Areas : electrical and computer engineeringB. Fani 1 , M. Moazzami 2 * , E. Farhoodi 3
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Keywords: Microgriddroop controllerislanding operationvoltage harmonic,
Abstract :
Microgrid technology makes possible coordination and effective use of different energy resources for supplying loads. In order to have synchronous operation between inverter resources during the occurrence of islanding condition, the use of droop controller structure would be beneficial. In this paper, the conventional droop controller is modified to divide proportional power between resources and cause accurate voltage setting in output resources. By providing a model for connected inverter to the nonlinear load, a harmonic droop controller has been designed. By droop controller related to each harmonic, the harmonic voltages are calculated and add to the reference voltage. Therefore the quality of the output voltage is improved. Then the inverter voltage control loop would be modified with resistance impedance in the presence of non-linear loads, so that, in combination with harmonic droop controller, THD of output voltage considerably reduced. Simulation results show the ability of suggested method in reduction of harmonic voltages in inverters parallel operation.
[1] H. Liu, Y. Chen, M. C. Chuah, J. Yang, and H. V. Poor, "Enabling self-healing smart grid through jamming resilient local controller switching," IEEE Trans. on Dependable and Secure Computing, vol. 14, no. 4, pp. 377-391, Jul./ Aug. 2017.
[2] M. Bloemink and M. R. Iravani, "Control of a multiple source microgrid with built-in islanding detection and current limiting," IEEE Trans. on Smart Grid, vol. 27, no. 4, pp. 2122-2132, Oct. 2012.
[3] P. Prabhakaran, Y. Goyal, and V. Agarwal, "Novel nonlinear droop control techniques to overcome the load sharing and voltage regulation issues in DC microgrid," IEEE Trans. on Power Electronics, vol. 33, no. 5, pp. 4477-4487, May 2018.
[4] F. Blaabjerg, M. Liserre, and K. Ma, "Power electronics converter for wind turbine systems," IEEE Trans. on Industry Applications, vol. 48, no. 2, pp. 708-719, Mar./Apr. 2012.
[5] Y. Guo, X. Lu, L. Chen, T. Zheng, J. Wang, and S. Mei, "Functional-rotation-based active dampers in AC microgrids with multiple parallel interface inverters," IEEE Trans. on Industry Applications, vol. 54, no. 5, pp. 5206-5215, Sept./Oct. 2018.
[6] A. Mortezaei, M. G. Simoes, M. Savaghebi, J. M. Guerrero, and A. A. Durra, "Cooperative control of multi-master-slave islanded microgrid with power quality enhancement based on conservative power theory," IEEE Trans. on Smart Grid, vol. 9, no. 4, pp. 2964-2975, Jul. 2018.
[7] Q. Zhong, F. Blaabjerg, and J. Guerrero, "Reduction of voltage harmonics for parallel-operated inverters equipped with a robust droop controller," IEEE Energy Conversion Congress and Exposition, ECCE'11, pp. 473-478, Phoenix, AZ, USA, 17-22 Sept. 2011.
[8] M. Siahi, M. Najafi, and M. H. Seynpoor, "Design and simulation of UPQC to improve power quality and transfer power of photovoltaic array to grid," Australian J. of Basic and Applied Science, vol. 5, no. 3, pp. 662-673, 2011.
[9] M. Prodanovi and T. C. Green, "High-quality power generation through distributed control of a power park microgrid," IEEE Trans. on Industrial Electronics, vol. 53, no. 5, pp. 1471-1482, Oct. 2006.
[10] N. S. Srivatchan, P. Rangarajan, and S. R. ajalakshmi, "Control scheme for power quality improvement in islanded microgrid operation," Procedia Technology, vol. 21, pp. 212-215, Aug. 2015.
[11] J. He and M. Shirajum, "A flexible harmonic control approach through voltage-controlled DG-grid Interfacing converters," IEEE Trans. on Industrial Electronics, vol. 59, no. 1, pp. 444-455, Jan. 2012.
[12] M. Savaghebi, J. C. Vasquez, A. Jalilan, J. M. Guerrero, and T. L. Lee, "Selective compensation of voltage harmonics in grid-connected microgrids," Mathematicsand Computersin Simulation, vol. 91, pp. 211-228, May 2012.
[13] M. Savaghebi, J. C. Vasquez, A. Jalilan, and J. M. Guerrero, "Secondary control for voltage quality enhancement in microgrids," IEEE Trans. on Smart Grid, vol. 3, no. 4, pp. 1893-1902, Dec. 2013.
[14] J. He and X. Wang, "Active harmonic filtering using current-controlled, grid-connected DG units with closed-loop power control," IEEE Trans. on Power Electronics, vol. 29, no. 2, pp. 642-653, Feb. 2014.
[15] D. Li and Z. Q. Zhu, "A novel integrated power quality controller for microgrid," IEEE Trans. on Industrial Electronics, vol. 62, no. 5, pp. 2848-2858, May 2015.
[16] Q. C. Zhong, "Harmonic droop controller to reduce the voltage harmonics of inverters," IEEE Trans. on Industrial Electronics, vol. 60, no. 3, pp. 936-945, Mar. 2013.
[17] A. Bidram and A. Davoudi, "Hierarchical structure of microgrids control system," IEEE Trans. on Smart Grid, vol. 3, no. 4, pp. 1963-1976, Dec. 2012.
[18] Q. C. Zhong, "Robust droop controller for accurate proportional loadsharing among inverters operated in parallel," IEEE Trans. on Industrial Electronics, vol. 60, no. 4, pp. 1281-1290, Apr. 2013.
[19] -, IEEE Guide for Design, Operation, and Integration of Distributed Resource Island Systems with Electric Power Systems, IEEE Standard 1547.4, Jul. 2011.