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Title: A framework to analyze the stochastic harmonics and resonance of wind energy grid interconnection

Abstract

This study addresses a modeling and analysis methodology for investigating the stochastic harmonics and resonance concerns of wind power plants (WPPs). Wideband harmonics from modern wind turbines are observed to be stochastic, associated with real power production, and they may adversely interact with the grid impedance and cause unexpected harmonic resonance if not comprehensively addressed in the planning and commissioning of the WPPs. These issues should become more critical as wind penetration levels increase. We thus propose a planning study framework comprising the following functional steps: First, the best-fitted probability density functions (PDFs) of the harmonic components of interest in the frequency domain are determined. In operations planning, maximum likelihood estimations followed by a chi-square test are used once field measurements or manufacturers' data are available. Second, harmonic currents from the WPP are represented by randomly-generating harmonic components based on their PDFs (frequency spectrum) and then synthesized for time-domain simulations via inverse Fourier transform. Finally, we conduct a comprehensive assessment by including the impacts of feeder configurations, harmonic filters, and the variability of parameters. We demonstrate the efficacy of the proposed study approach for a 100-MW offshore WPP consisting of 20 units of 5-MW full-converter turbines, a realistic benchmark systemmore » adapted from a WPP under development in Korea, and discuss lessons learned through this research.« less

Authors:
 [1];  [1]; ORCiD logo [1];  [2];  [3];  [4];  [4];  [4]
  1. Yonsei Univ., Seoul (Korea)
  2. Chonbuk National Univ., Jeonju (Korea)
  3. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  4. Korea Electric Power Research Institute, Daejeon (Korea)
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1327214
Report Number(s):
NREL/JA-5D00-67044
Journal ID: ISSN 1996-1073; ENERGA
Grant/Contract Number:
AC36-08GO28308
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Energies (Basel)
Additional Journal Information:
Journal Name: Energies (Basel); Journal Volume: 9; Journal Issue: 9; Journal ID: ISSN 1996-1073
Publisher:
MDPI AG
Country of Publication:
United States
Language:
English
Subject:
17 WIND ENERGY; 24 POWER TRANSMISSION AND DISTRIBUTION; wind power plant; WPP; harmonics; resonance; statistical modeling

Citation Formats

Cho, Youngho, Lee, Choongman, Hur, Kyeon, Kang, Yong Cheol, Muljadi, Eduard, Park, Sang -Ho, Choy, Young -Do, and Yoon, Gi -Gab. A framework to analyze the stochastic harmonics and resonance of wind energy grid interconnection. United States: N. p., 2016. Web. doi:10.3390/en9090700.
Cho, Youngho, Lee, Choongman, Hur, Kyeon, Kang, Yong Cheol, Muljadi, Eduard, Park, Sang -Ho, Choy, Young -Do, & Yoon, Gi -Gab. A framework to analyze the stochastic harmonics and resonance of wind energy grid interconnection. United States. doi:10.3390/en9090700.
Cho, Youngho, Lee, Choongman, Hur, Kyeon, Kang, Yong Cheol, Muljadi, Eduard, Park, Sang -Ho, Choy, Young -Do, and Yoon, Gi -Gab. 2016. "A framework to analyze the stochastic harmonics and resonance of wind energy grid interconnection". United States. doi:10.3390/en9090700. https://www.osti.gov/servlets/purl/1327214.
@article{osti_1327214,
title = {A framework to analyze the stochastic harmonics and resonance of wind energy grid interconnection},
author = {Cho, Youngho and Lee, Choongman and Hur, Kyeon and Kang, Yong Cheol and Muljadi, Eduard and Park, Sang -Ho and Choy, Young -Do and Yoon, Gi -Gab},
abstractNote = {This study addresses a modeling and analysis methodology for investigating the stochastic harmonics and resonance concerns of wind power plants (WPPs). Wideband harmonics from modern wind turbines are observed to be stochastic, associated with real power production, and they may adversely interact with the grid impedance and cause unexpected harmonic resonance if not comprehensively addressed in the planning and commissioning of the WPPs. These issues should become more critical as wind penetration levels increase. We thus propose a planning study framework comprising the following functional steps: First, the best-fitted probability density functions (PDFs) of the harmonic components of interest in the frequency domain are determined. In operations planning, maximum likelihood estimations followed by a chi-square test are used once field measurements or manufacturers' data are available. Second, harmonic currents from the WPP are represented by randomly-generating harmonic components based on their PDFs (frequency spectrum) and then synthesized for time-domain simulations via inverse Fourier transform. Finally, we conduct a comprehensive assessment by including the impacts of feeder configurations, harmonic filters, and the variability of parameters. We demonstrate the efficacy of the proposed study approach for a 100-MW offshore WPP consisting of 20 units of 5-MW full-converter turbines, a realistic benchmark system adapted from a WPP under development in Korea, and discuss lessons learned through this research.},
doi = {10.3390/en9090700},
journal = {Energies (Basel)},
number = 9,
volume = 9,
place = {United States},
year = 2016,
month = 8
}

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