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

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

DOI QR Code

Normal Operation Characteristics of 30kW Scale CVCF Inverter-Based Micro-grid System

30kW급 CVCF 인버터 기반의 Micro-grid의 정상상태 운용특성에 관한 연구

  • Ferreira, Marito (Dept. of Electrical Engineering, Korea University of Technology and Education) ;
  • Lee, Hu-Dong (Dept. of Electrical Engineering, Korea University of Technology and Education) ;
  • Tae, Dong-Hyun (Dept. of Electrical Engineering, Korea University of Technology and Education) ;
  • Rho, Dae-Seok (Dept. of Electrical Engineering, Korea University of Technology and Education)
  • Received : 2020.05.13
  • Accepted : 2020.06.05
  • Published : 2020.06.30
Download PDF
⟨ Previous Next ⟩

Abstract

Recently, for the purposes of reducing carbon dioxide(CO2) emissions in the island area, countermeasures to decrease the operation rate of diesel generator(DG) and to increase one of renewable energy sources(RES) is being studied. In particular, the demonstration and installation of stand-alone micro-grid(MG) system which is composed of DG, RES and energy storage system(ESS) has been implemented in some island areas such as Gapa-do, Gasa-do and Ulleung-do island. However, many power quality(PQ) problems may be occurred due to an intermittent output of RES including photovoltaic(PV) system and wind power(WP) system in a normal operating of constant voltage & constant frequency(CVCF) inverter-based MG system. Therefore, this paper presents a modeling of the 30kW scale MG system using PSCAD/EMTDC, and also implements a 30kW scale CVCF inverter-based MG system as test devices to analyze normal operating characteristics of MG system. From the simulation and test results, it is confirmed that the proposed methods are useful and practical tools to improve PQ problems such as under-voltage, over-voltage and unbalanced load in CVCF inverter-based MG system.

최근, 국·내외적으로 CO2배출의 저감을 위한 기술적인 방안 중 하나로 도서지역의 마이크로그리드에 기 설치된 디젤발전기의 가동률을 줄이고 신재생에너지전원의 비중을 높여 운용하고 있는 실정이다. 특히, 국내에서는 가파도, 가사도, 울릉도 등의 도서지역에 디젤발전기와 신재생에너지, 전기저장장치로 구성된 독립형 마이크로그리드의 실증 및 보급 사업이 활발하게 진행되고 있으며, 기존의 디젤발전기 대신 정전압, 정주파수(constant voltage constant frequency, CVCF) 기능을 가진 CVCF 인버터 및 CVCF 인버터용 배터리를 도입하여 마이크로그리드를 안정적으로 운용하는 연구들이 진행되고 있다. 그러나, CVCF 인버터 기반 마이크로그리드의 정상상태 운용특성에 있어서, 출력이 불안정한 태양광전원과 풍력발전과 같은 신재생에너지전원이 계통에 연계되면서 전력품질에 많은 문제가 발생하고 있다. 따라서, 본 논문에서는 신재생에너지전원과 전기저장장치 연계에 따른 마이크로그리드의 운용특성을 분석하기 위하여, PSCAD/EMTDC를 이용하여 30kW급 마이크로그리드 시스템을 모델링하고, 이를 바탕으로 마이크로그리드 시험장치를 구현한다. 30kW급 마이크로그리드 시스템을 바탕으로 시뮬레이션 및 시험을 수행한 결과, 제안한 방법이 CVCF 인버터 기반의 마이크로그리드 시스템에서 저전압, 과전압 및 불평형 문제를 개선하는 데 유용함을 확인하였다.

Keywords

References

  1. IEC white paper, "Microgrids for disaster preparedness and recovery with electricity continuity plans systems", originally published in March, 2014.
  2. Kohn, Z. B. Zabinsky and A. Nerode, "A Micro-Grid Distributed Intelligent Control and Management System", IEEE Transactions on Smart Grid, vol. 6, no. 6, pp. 2964-2974, 2015. DOI: https://doi.org/10.1109/TSG.2015.2455512
  3. Mohamad Faisal, M.A. Hannam, Pin Jern Ker, Aini Hussain, "Review of Storage system technology in microgrid application: Issues and challenges", IEEE Access Special section on advance energy storage technology and their applications, vol. 6, no. 6, pp. 35143-35164, 2018. DOI: https://doi.org/10.1109/ACCESS.2018.2841407
  4. Dong-Wan Kim, Ji-Han Ko, Seong Hyun Kim, Homin Kim, "Renewable Energy Configuration Plan of Micro Grid in Gapa Island", Journal of the Korean Solar Energy Society, vol. 34, no. 2, pp. 16-32, 2014. DOI: https://doi.org/10.7836/kses.2014.34.2.016
  5. M.S. Mahmoud, S. Azher Hussain, M.A.Abido," Modeling and control of microgrid: An overview" Journal of the Franklin Institute, vol. 351. no. 5, pp. 2822-2859, 2014. DOI: https://doi.org/10.1016/j.jfranklin.2014.01.016
  6. Vinayangam Arangarajan, Swarna KVS, Yong Sheon Khoo, Alex Stojcevski, "Power Quality Analysis in Microgrid: An Experimental Approach", Journal of Power and Energy Engineering, vol. 4, no. 4, 2016. DOI: https://doi.org/10.7836/kses.2014.34.2.016
  7. Sung-Sik Choi, Min-Kwan Kang, Hu-Dong Lee, Yang-Hyun Nam, Dae-Seok Rho, "A stable Operation Strategy in Micro-grid Systems without Diesel Generators", Journal of Electric Engineering and Technology, vol. 13, no. 1, pp. 114-123, 2018. DOI: http://doi.org/10.5370/JEET.2018.13.1.114
  8. B. V. Solanki, A. Raghurajan, K. Bhattacharya and C. A. Canizares, "Including Smart Loads for Optimal Demand Response in Integrated Energy Management Systems for Isolated Microgrids", IEEE Transactions on Smart Grid, vol. 8, no. 4, pp. 1739-1748, 2017. DOI: https://doi.org/10.1109/TSG.2015.2506152
  9. Woo-Hyun Hwang, Sang-Kyu Kim, Jung-Ho Lee, Woo-Kyu Chae, Je-Ho Lee, Hyun-Jun Lee, Jae-Eon Kim "Autonomous Micro-grid Design for Supplying Electricity in Carbon-Free Island", Journal of Electrical Engineering & Technology, vol. 9, no. 3, pp. 1112-1118, 2014. DOI: http://dx.doi.org/10.5370/JEET.2014.9.3.1112
  10. Seung-Ho Kim, Sung-Sik Choi, Seung-Jong Kim, Dae-Seok Rho, "Single-phase Control Algorithm of 4-Leg type PCS for Micro-grid System", Korea Academy Industrial Cooperation Society, vol. 18, no. 11, pp. 817-825, 2017. DOI: https://doi.org/10.5762/KAIS.2017.18.11.817