A novel droop control method for distribution loss minimization in DC microgrids with decentralized communication

Dc microgrids including grid-tied inverter, energy storage system, and distributed generations have the advantage of high efficiency as compared to the ac system. Droop control has been realized to suppress the current mismatching among distributed sources. However, the conventional droop control involves distribution loss due to the line impedance. In this paper, a novel droop control is proposed to minimize the distribution loss by adjusting controllable droop coefficient. The control objective of the novel droop control is that energy storage system supplies the most adjacent load with their energy within rated power. Hence, the distribution loss can be minimized significantly by tracking the new reference voltage in order to maintain same output voltage of each converter. Simulation results based on PSCAD/EMTDC are provided to verify proposed droop control method.

[1]  H. Mokhtari,et al.  An adaptive droop control method for low voltage DC microgrids , 2014, The 5th Annual International Power Electronics, Drive Systems and Technologies Conference (PEDSTC 2014).

[2]  N. Theethayi,et al.  The Influence of Load Impedance, Line Length, and Branches on Underground Cable Power-Line Communications (PLC) Systems , 2008, IEEE Transactions on Power Delivery.

[3]  Wang Wei,et al.  An autonomous control scheme for DC micro-grid system , 2013, IECON 2013 - 39th Annual Conference of the IEEE Industrial Electronics Society.

[4]  Dushan Boroyevich,et al.  Grid-Interface Bidirectional Converter for Residential DC Distribution Systems—Part One: High-Density Two-Stage Topology , 2013, IEEE Transactions on Power Electronics.

[5]  Dushan Boroyevich,et al.  Future electronic power distribution systems a contemplative view , 2010, 2010 12th International Conference on Optimization of Electrical and Electronic Equipment.

[6]  B. G. Fernandes,et al.  Distributed Control to Ensure Proportional Load Sharing and Improve Voltage Regulation in Low-Voltage DC Microgrids , 2013, IEEE Transactions on Power Electronics.

[7]  H. Akagi,et al.  DC microgrid based distribution power generation system , 2004, The 4th International Power Electronics and Motion Control Conference, 2004. IPEMC 2004..

[8]  Yunjie Gu,et al.  Mode-Adaptive Decentralized Control for Renewable DC Microgrid With Enhanced Reliability and Flexibility , 2014, IEEE Transactions on Power Electronics.

[9]  Juan C. Vasquez,et al.  Hierarchical Control of Droop-Controlled AC and DC Microgrids—A General Approach Toward Standardization , 2009, IEEE Transactions on Industrial Electronics.

[10]  Juan C. Vasquez,et al.  An Improved Droop Control Method for DC Microgrids Based on Low Bandwidth Communication With DC Bus Voltage Restoration and Enhanced Current Sharing Accuracy , 2014, IEEE Transactions on Power Electronics.