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Title: Power Smoothing of a Variable-Speed Wind Turbine Generator in Association With the Rotor-Speed-Dependent Gain

Abstract

This paper proposes a power-smoothing scheme for a variable-speed wind turbine generator (WTG) that can smooth out the WTG's fluctuating power caused by varying wind speeds, and thereby keep the system frequency within a narrow range. The proposed scheme employs an additional loop based on the system frequency deviation that operates in conjunction with the maximum power point tracking (MPPT) control loop. Unlike the conventional, fixed-gain scheme, its control gain is modified with the rotor speed. In the proposed scheme, the control gain is determined by considering the ratio of the output of the additional loop to that of the MPPT loop. To improve the contribution of the scheme toward maintaining the frequency while ensuring the stable operation of WTGs, in the low rotor speed region, the ratio is set to be proportional to the rotor speed; in the high rotor speed region, the ratio remains constant. The performance of the proposed scheme is investigated under varying wind conditions for the IEEE 14-bus system. The simulation results demonstrate that the scheme successfully operates regardless of the output power fluctuation of a WTG by adjusting the gain with the rotor speed, and thereby improves the frequency-regulating capability of a WTG.

Authors:
; ; ; ;
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:
1373680
Report Number(s):
NREL/JA-5D00-68989
Journal ID: ISSN 1949-3029
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: IEEE Transactions on Sustainable Energy; Journal Volume: 8; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
24 POWER TRANSMISSION AND DISTRIBUTION; fluctuation; frequency deviation loop; power smoothing; rotor-speed-dependent gain; stable operation

Citation Formats

Kim, Yeonhee, Kang, Moses, Muljadi, Eduard, Park, Jung-Wook, and Kang, Yong Cheol. Power Smoothing of a Variable-Speed Wind Turbine Generator in Association With the Rotor-Speed-Dependent Gain. United States: N. p., 2017. Web. doi:10.1109/TSTE.2016.2637907.
Kim, Yeonhee, Kang, Moses, Muljadi, Eduard, Park, Jung-Wook, & Kang, Yong Cheol. Power Smoothing of a Variable-Speed Wind Turbine Generator in Association With the Rotor-Speed-Dependent Gain. United States. doi:10.1109/TSTE.2016.2637907.
Kim, Yeonhee, Kang, Moses, Muljadi, Eduard, Park, Jung-Wook, and Kang, Yong Cheol. Sat . "Power Smoothing of a Variable-Speed Wind Turbine Generator in Association With the Rotor-Speed-Dependent Gain". United States. doi:10.1109/TSTE.2016.2637907.
@article{osti_1373680,
title = {Power Smoothing of a Variable-Speed Wind Turbine Generator in Association With the Rotor-Speed-Dependent Gain},
author = {Kim, Yeonhee and Kang, Moses and Muljadi, Eduard and Park, Jung-Wook and Kang, Yong Cheol},
abstractNote = {This paper proposes a power-smoothing scheme for a variable-speed wind turbine generator (WTG) that can smooth out the WTG's fluctuating power caused by varying wind speeds, and thereby keep the system frequency within a narrow range. The proposed scheme employs an additional loop based on the system frequency deviation that operates in conjunction with the maximum power point tracking (MPPT) control loop. Unlike the conventional, fixed-gain scheme, its control gain is modified with the rotor speed. In the proposed scheme, the control gain is determined by considering the ratio of the output of the additional loop to that of the MPPT loop. To improve the contribution of the scheme toward maintaining the frequency while ensuring the stable operation of WTGs, in the low rotor speed region, the ratio is set to be proportional to the rotor speed; in the high rotor speed region, the ratio remains constant. The performance of the proposed scheme is investigated under varying wind conditions for the IEEE 14-bus system. The simulation results demonstrate that the scheme successfully operates regardless of the output power fluctuation of a WTG by adjusting the gain with the rotor speed, and thereby improves the frequency-regulating capability of a WTG.},
doi = {10.1109/TSTE.2016.2637907},
journal = {IEEE Transactions on Sustainable Energy},
number = 3,
volume = 8,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}
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  • No abstract prepared.