Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
권호 표지
DOI QR코드

DOI QR Code

Optimal Operation Algorithm of Protection Devices in Distribution Systems With PV System

대용량 태양광전원이 연계된 배전선로에 있어서 보호협조기기의 최적 운용알고리즘

  • Kwon, Soon-hwan (Information School, Korea University of Technology) ;
  • Lee, Hu-dong (Information School, Korea University of Technology) ;
  • Nam, Yang-hyun (Information School, Korea University of Technology) ;
  • Rho, Dae-seok (Information School, Korea University of Technology)
  • 권순환 (한국기술교육대 전기전자통신공학부) ;
  • 이후동 (한국기술교육대 전기전자통신공학부) ;
  • 남양현 (한국기술교육대 전기전자통신공학부) ;
  • 노대석 (한국기술교육대 전기전자통신공학부)
  • Received : 2018.03.21
  • Accepted : 2018.05.04
  • Published : 2018.05.31
Download PDF
⟨ Previous Next ⟩

Abstract

If a photovoltaic (PV) system is installed in a primary feeder interconnected with the PV system, bi-directional power flow can occur, and then, the magnitude and direction of the fault current can change, depending on the fault location and point of common coupling (PCC) of the PV system, and the time current curve (TCC) cannot be properly coordinated between protection devices. Also, it is difficult to obtain a proper time interval for protection devices because the conventional setting approach is applied, even though the PV system is installed and operating. Therefore, this paper presents three operation modes considering the operational conditions of the PV system to obtain setting values for protection devices. Based on the mode, this paper proposes an algorithm to calculate the optimal protection coordination time interval according to the introduction capacity of the PV system. In addition, this paper performs modelling of a distribution system with the PV system and protection devices by using Off-DAS S/W, and analyzes the characteristics of the time interval between the protection devices, such as substation relays, reclosers, customer relays, and PV customer relays. The simulation results confirmed that the proposed operational modes and setting-value algorithms are useful and effective for protection coordination in a distribution system for a PV system.

최근, 대용량의 태양광전원이 연계된 배전계통은 기존의 단방향과 달리 양방향의 조류가 발생하고, 태양광전원의 연계위치 및 고장위치에 따라 사고전류의 크기와 방향이 변하여, 보호기기간의 협조시간차가 충분히 확보되지 않는 문제점이 발생할 수 있다. 또한, 태양광전원을 고려하지 않은 기존의 보호기기 정정치를 그대로 적용하고 있어 보호기기간의 협조시간차를 확보하기 어려운 상황이 발생하고 있다. 따라서 본 논문에서는 태양광전원이 연계된 선로에서 고려할 수 있는 3가지 Case의 보호기기 정정치 운용모드를 제시하고, 이를 바탕으로 태양광전원의 용량에 따른 최적의 보호협조 시간을 도출할 수 있는 알고리즘을 제안한다. 한편, 이를 바탕으로 보호협조 전용소프트웨어인 Off-DAS를 이용하여, 태양광전원이 연계된 배전계통을 모델링하고, 보호기기(변전소 계전기, 리클로저(Recloser), 고객계전기, 태양광전원 고객계전기)간의 협조시간차 특성을 분석한다. 실 계통을 대상으로 시뮬레이션을 수행한 결과, 본 논문에서 제시한 보호기기의 정정치 운용 모드와 정정치 산정 방식이 태양광 전원이 연계된 배전계통 보호기기간의 협조시간을 안정적으로 확보할 수 있음을 알 수 있었다.

Keywords

References

  1. Guideline for Interconnection of Distributed Generation System in Distribution Systems, KEPCO, June, 2012.
  2. Daeseok Rho, "A Study on the Fault Characteristics of Wind Power in Primary Feeder", Journal of KAIS, vol. 13, no. 3, pp. 1288-1295, March, 2012.
  3. R. F. Arritt, R. C. Dugan "Distributed generation interconnection transformer and grounding selection", Power and Energy Society General Meeting-Conversion and Delivery of Electrical Energy in the 21st Century, IEEE. pp. 1-7, 2008. DOI: https://doi.org/10.1109/PES.2008.4596772
  4. A. Girgis, S. Brahma, "Effect of Distributed Generation on Protective Device Coordination in Distribution System", Power Engineering, LESCOPE '01. 2001 Large Engineering Systems Conference, 11-13, pp. 115-119, July, 2001. DOI: https://doi.org/10.1109/LESCPE.2001.941636
  5. Dae-seok Rho, "Countermeasures on bi-directional Protective Device Coordination of smart grid connected to new energy generation", The world of electric, vol. 5, no. 9, pp. 39-43, 2010.
  6. So-Hee Kim, Dae-seok Rho, "Development of Operation System for Customer Protection Devices with Distributed Generation", Korea Academia-industrial cooperation society, announced Fall conference proceedings in 2010, pp. 62-65, nov. 2010.
  7. IEEE 1547.1 "IEEE Standard conformance Test Procedures for Equipment Interconnecting Distributed Resources with Electric Power System", J. IEEE June, 2005. DOI: https://doi.org/10.1109/IEEESTD.2005.96289
  8. So-Hee Kim and Dae-seok Rho, "Evaluation Algorithm for Coordination Protection Between Recloser and Distributed Generation Relay", Korea Academia-industrial cooperation society, announced Spring conference proceedings in 2010, pp. 69-72, May, 2011.
  9. Byeon-Gi Kim, Jae-Beom Park, Kyeong-Sang You, Dae-Seok Rho, "Optimal Operation Methods of Protection Devices in Distribution Systems with PV Systems", The Korean Institute of Electrical Engineers, vol. 60, no. 8, pp. 1485-1491, Aug. 2011. DOI: https://doi.org/10.5370/KIEE.2011.60.8.1485
  10. Korea Electric Power Research Institute, "Distribution Protection Description", pp. 70-91, Oct. 2008.
  11. Se-Young Pyo, Oh-Seok Kwon, Kee-Hwan Kim, A Study on Efficient Management of Solar Powered LED Street Lamp Using Weather forecast, The Journal of The Institute of Internet, Broadcasting and Communication (IIBC), Vol. 15, No. 2, pp. 129-135, Apr. 2015. DOI: http://dx.doi.org/10.7236/JIIBC.2015.15.2.129
  12. Sung-Ho Hwang, Eun-Young Kang, Performance Analysis of IEEE 802.15.4 for D1 Small Distribution Substation, The Journal of The Institute of Internet, Broadcasting and Communication (IIBC), Vol. 17, No. 1, pp.115-121, Feb. 2017. DOI: https://doi.org/10.7236/JIIBC.2017.17.1.115