Journal of Electrical Engineering and Technology

The Korean Institute of Electrical Engineers (대한전기학회)
권호 표지
DOI QR코드

DOI QR Code

Coordinated Voltage Control Scheme for Multi-Terminal Low-Voltage DC Distribution System

  • Trinh, Phi Hai (School of Electrical Engineering, Kookmin University) ;
  • Chung, Il-Yop (School of Electrical Engineering, Kookmin University) ;
  • Kim, Taehoon (Korea Electric Power Research Institute (KEPRI)) ;
  • Kim, Juyong (Korea Electric Power Research Institute (KEPRI))
  • Received : 2017.11.22
  • Accepted : 2018.02.11
  • Published : 2018.07.01
Download PDF
⟨ Previous Next ⟩

Abstract

This paper focuses on voltage control schemes for multi-terminal low-voltage direct current (LVDC) distribution systems. In a multi-terminal LVDC distribution system, there can be multiple AC/DC converters that connect the LVDC distribution system to the AC grids. This configuration can provide enhanced reliability, grid-supporting functionality, and higher efficiency. The main applications of multi-terminal LVDC distribution systems include flexible power exchange between multiple power grids and integration of distributed energy resources (DERs) using DC voltages such as photovoltaics (PVs) and battery energy storage systems (BESSs). In multi-terminal LVDC distribution systems, voltage regulation is one of the most important issues for maintaining the electric power balance between demand and supply and providing high power quality to end customers. This paper focuses on a voltage control method for multi-terminal LVDC distribution system that can efficiently coordinate multiple control units, such as AC/DC converters, PVs and BESSs. In this paper, a control hierarchy is defined for undervoltage (UV) and overvoltage (OV) problems in LVDC distribution systems based on the control priority between the control units. This paper also proposes methods to determine accurate control commands for AC/DC converters and DERs. By using the proposed method, we can effectively maintain the line voltages in multi-terminal LVDC distribution systems in the normal range. The performance of the proposed voltage control method is evaluated by case studies.

Keywords

References

  1. Starke, M., Tolbert, L.M., Ozpineci, B., "AC vs DC distribution: A loss comparison," Transmission and Distribution Conference and Exposition, IEEE/PES, 2008, Chicago, IL, USA, April 22-24.
  2. Whaite, S., Grainger, B., Kwasinski, A., "Power quality in DC distribution systems and microgrid," Energies, vol. 8, no. 5, pp. 4378-4399, May, 2015. https://doi.org/10.3390/en8054378
  3. Nuutinen, P., Kaipia, T., Peltoniemi, P., Lana, A., Pinomaa, A., Mattsson, A., Silventoinen, P., Partanen, J., Lohjala, J., Matikainen, M., "Research Site for Low-Voltage Direct Current Distribution in a Utility Network - Structure, Functions, and Operation," IEEE Transactions on Smart Grid, vol. 5, no. 5, pp. 2574-2582, 2014. https://doi.org/10.1109/TSG.2014.2308365
  4. Kim, J., Kim, J., Cho, J., Song, I., Kweon, B., Chung, I., Choi, J., "Comparison between Underground Cable and Overhead Line for a Low-Voltage Direct Current Distribution Network Serving Communication Repeater," Energies, vol. 7, no. 3, pp. 1656-1672, 2014. https://doi.org/10.3390/en7031656
  5. Chung, I., Trinh, P.H., Cho, H., Kim, J., Cho, J., Kim, T. "Design and Evaluation of Voltage Control Techniques by Hierarchical Coordination of Multiple Power Converters in Low-Voltage DC Distribution Systems," 2016 CIRED Workshop, Helsinki 14-15 June 2016.
  6. Zhong, Q., Nguyen, P., Ma, Z., Sheng, W. "Self- Synchronized Synchronverters: Inverters without a delicated synchronization unit," IEEE transactions on power electronics, vol. 29, no. 2, 2014.
  7. Cairoli, P., Dougal, R.A., Lentijo, K., "Coordination between supply power converters and contactors for fault protection in multi-terminal MVDC distribution systems," IEEE Electric Ship Technologies Symposium (ESTS), 2013, Arlington, VA, USA.
  8. Chen, D., Xu, L., Zhang, W., "Active distribution system with multi-terminal MVDC links," IEEE Renewable Power Generation (RPG 2015), 2015, Beijing, China.
  9. Monadi, M., Koch-Ciobotaru, C., Luna, A., Candela, J.I., Rodriguez, P., "A protection strategy for fault detection and location for multi-terminal MVDC distribution system with renewable energy systems," IEEE Renewable Research and Application (ICRERA), Milwaukee, Wl, USA, 2014.
  10. Majumder, R., "Aggregation of microgrids with DC system," Electric Power Systems Research, vol. 108, pp. 134-143, 2014. https://doi.org/10.1016/j.epsr.2013.11.013
  11. Yang, J., Fletcher, J.E., O'Reilly, J., "Short-circuit and ground fault analyses and location in VSC- based DC networks cable," IEEE Transactions on Industrial Electronics, vol. 59, issue 10, pp. 3827- 3837, Oct. 2012. https://doi.org/10.1109/TIE.2011.2162712
  12. Larruskain, D.M., Zamora, I., Abarrategui, O., Aginako, Z., "Conversion of AC distribution system lines into DC lines to upgrades transmission capacity," Electric Power Systems Research, vol. 81, pp. 1341- 1348, 2011. https://doi.org/10.1016/j.epsr.2011.01.020
  13. Kweon, B., Chung, I., Kim, J., Cho, J., "Design and operation schemes for battery energy storage systems in low-voltage DC distribution systems considering voltage control and economic feasibility," CRIED, 2015, Lyon, France.
  14. Kang, H., Chung, I., Moon, S., "Voltage Control Method Using Distributed Generators based on a Multi-Agent System," Energies, vol. 8, pp. 14009- 14025, 2015. https://doi.org/10.3390/en81212411
  15. Std, ANSI C84. 1-2011, "American National Standard for Electric Power Systems and Equipment-Voltage Ratings (60 Hertz)," 2011.
  16. Jeong, H., Choi, J., Won, D., Ahn, S., Moon, S., "Formulation and Analysis of an Approximate Expression for Voltage Sensitivity in Radial DC Distribution Systems," Energies, vol. 8, no. 9, pp. 9296-9319, 2015. https://doi.org/10.3390/en8099296
  17. Hamad, A., Farag, H., El-Saadany, E. A., "Novel Multi-agent Control Scheme for Voltage Regulation in DC Distribution Systems," IEEE Trans. On Sustainable Energy, vol. 6, no. 5, pp. 534-545, 2015. https://doi.org/10.1109/TSTE.2015.2391114
  18. Hai, T.P., Cho, H., Chung, I., Kang, H., Cho, J., Kim, J., "A novel voltage control scheme for low-voltage DC distribution systems using multi-agent systems," Energies, vol. 10, doi: 10.3390/en10010041.