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Title: Review of Reactive Power Dispatch Strategies for Loss Minimization in a DFIG-based Wind Farm

Abstract

This study reviews and compares the performance of reactive power dispatch strategies for the loss minimization of Doubly Fed Induction Generator (DFIG)-based Wind Farms (WFs). Twelve possible combinations of three WF level reactive power dispatch strategies and four Wind Turbine (WT) level reactive power control strategies are investigated. All of the combined strategies are formulated based on the comprehensive loss models of WFs, including the loss models of DFIGs, converters, filters, transformers, and cables of the collection system. Optimization problems are solved by a Modified Particle Swarm Optimization (MPSO) algorithm. The effectiveness of these strategies is evaluated by simulations on a carefully designed WF under a series of cases with different wind speeds and reactive power requirements of the WF. The wind speed at each WT inside the WF is calculated using the Jensen wake model. The results show that the best reactive power dispatch strategy for loss minimization comes when the WF level strategy and WT level control are coordinated and the losses from each device in the WF are considered in the objective.

Authors:
 [1];  [1];  [1]; ORCiD logo [2];  [1];  [1]
  1. Aalborg Univ., Aalborg (Denmark)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
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:
1375312
Report Number(s):
NREL/JA-5D00-69054
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: 10; Journal Issue: 7; Journal ID: ISSN 1996-1073
Publisher:
MDPI AG
Country of Publication:
United States
Language:
English
Subject:
17 WIND ENERGY; 24 POWER TRANSMISSION AND DISTRIBUTION; doubly fed induction generator; reactive power dispatch; wind farm; loss minimization

Citation Formats

Zhang, Baohua, Hu, Weihao, Hou, Peng, Tan, Jin, Soltani, Mohsen, and Chen, Zhe. Review of Reactive Power Dispatch Strategies for Loss Minimization in a DFIG-based Wind Farm. United States: N. p., 2017. Web. doi:10.3390/en10070856.
Zhang, Baohua, Hu, Weihao, Hou, Peng, Tan, Jin, Soltani, Mohsen, & Chen, Zhe. Review of Reactive Power Dispatch Strategies for Loss Minimization in a DFIG-based Wind Farm. United States. doi:10.3390/en10070856.
Zhang, Baohua, Hu, Weihao, Hou, Peng, Tan, Jin, Soltani, Mohsen, and Chen, Zhe. 2017. "Review of Reactive Power Dispatch Strategies for Loss Minimization in a DFIG-based Wind Farm". United States. doi:10.3390/en10070856. https://www.osti.gov/servlets/purl/1375312.
@article{osti_1375312,
title = {Review of Reactive Power Dispatch Strategies for Loss Minimization in a DFIG-based Wind Farm},
author = {Zhang, Baohua and Hu, Weihao and Hou, Peng and Tan, Jin and Soltani, Mohsen and Chen, Zhe},
abstractNote = {This study reviews and compares the performance of reactive power dispatch strategies for the loss minimization of Doubly Fed Induction Generator (DFIG)-based Wind Farms (WFs). Twelve possible combinations of three WF level reactive power dispatch strategies and four Wind Turbine (WT) level reactive power control strategies are investigated. All of the combined strategies are formulated based on the comprehensive loss models of WFs, including the loss models of DFIGs, converters, filters, transformers, and cables of the collection system. Optimization problems are solved by a Modified Particle Swarm Optimization (MPSO) algorithm. The effectiveness of these strategies is evaluated by simulations on a carefully designed WF under a series of cases with different wind speeds and reactive power requirements of the WF. The wind speed at each WT inside the WF is calculated using the Jensen wake model. The results show that the best reactive power dispatch strategy for loss minimization comes when the WF level strategy and WT level control are coordinated and the losses from each device in the WF are considered in the objective.},
doi = {10.3390/en10070856},
journal = {Energies (Basel)},
number = 7,
volume = 10,
place = {United States},
year = 2017,
month = 6
}

Journal Article:
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  • Wake effects cause wind turbine generators (WTGs) within a wind power plant (WPP) to produce different levels of active power and subsequent reactive power capabilities. Further, the impedance between a WTG and the point of interconnection (POI)-which depends on the distance between them-impacts the WPP's reactive power injection capability at the POI. This paper proposes a voltage control scheme for a WPP based on the available reactive current of the doubly-fed induction generators (DFIGs) and its impacts on the POI to improve the reactive power injection capability of the WPP. In this paper, a design strategy for modifying the gainmore » of DFIG controller is suggested and the comprehensive properties of these control gains are investigated. In the proposed scheme, the WPP controller, which operates in a voltage control mode, sends the command signal to the DFIGs based on the voltage difference at the POI. The DFIG controllers, which operate in a voltage control mode, employ a proportional controller with a limiter. The gain of the proportional controller is adjusted depending on the available reactive current of the DFIG and the series impedance between the DFIG and the POI. The performance of the proposed scheme is validated for various disturbances such as a reactive load connection and grid fault using an EMTP-RV simulator. Furthermore, simulation results demonstrate that the proposed scheme promptly recovers the POI voltage by injecting more reactive power after a disturbance than the conventional scheme.« less
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