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Title: Improving the FLORIS wind plant model for compatibility with gradient-based optimization

Abstract

The FLORIS (FLOw Redirection and Induction in Steady-state) model, a parametric wind turbine wake model that predicts steady-state wake characteristics based on wind turbine position and yaw angle, was developed for optimization of control settings and turbine locations. This article provides details on changes made to the FLORIS model to make the model more suitable for gradient-based optimization. Changes to the FLORIS model were made to remove discontinuities and add curvature to regions of non-physical zero gradient. Exact gradients for the FLORIS model were obtained using algorithmic differentiation. A set of three case studies demonstrate that using exact gradients with gradient-based optimization reduces the number of function calls by several orders of magnitude. The case studies also show that adding curvature improves convergence behavior, allowing gradient-based optimization algorithms used with the FLORIS model to more reliably find better solutions to wind farm optimization problems.

Authors:
 [1];  [2];  [1]
  1. Department of Mechanical Engineering, Brigham Young University, Provo, UT, USA
  2. National Renewable Energy Laboratory, Golden, CO, USA
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:
1399845
Report Number(s):
NREL/JA-5000-70301
Journal ID: ISSN 0309-524X
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: Wind Engineering; Journal Volume: 41; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
17 WIND ENERGY; 29 ENERGY PLANNING, POLICY, AND ECONOMY; FLORIS; gradients; optimization; wake model; wind energy; wind farm design; wind turbine wake; yaw

Citation Formats

Thomas, Jared J., Gebraad, Pieter MO, and Ning, Andrew. Improving the FLORIS wind plant model for compatibility with gradient-based optimization. United States: N. p., 2017. Web. doi:10.1177/0309524X17722000.
Thomas, Jared J., Gebraad, Pieter MO, & Ning, Andrew. Improving the FLORIS wind plant model for compatibility with gradient-based optimization. United States. doi:10.1177/0309524X17722000.
Thomas, Jared J., Gebraad, Pieter MO, and Ning, Andrew. 2017. "Improving the FLORIS wind plant model for compatibility with gradient-based optimization". United States. doi:10.1177/0309524X17722000.
@article{osti_1399845,
title = {Improving the FLORIS wind plant model for compatibility with gradient-based optimization},
author = {Thomas, Jared J. and Gebraad, Pieter MO and Ning, Andrew},
abstractNote = {The FLORIS (FLOw Redirection and Induction in Steady-state) model, a parametric wind turbine wake model that predicts steady-state wake characteristics based on wind turbine position and yaw angle, was developed for optimization of control settings and turbine locations. This article provides details on changes made to the FLORIS model to make the model more suitable for gradient-based optimization. Changes to the FLORIS model were made to remove discontinuities and add curvature to regions of non-physical zero gradient. Exact gradients for the FLORIS model were obtained using algorithmic differentiation. A set of three case studies demonstrate that using exact gradients with gradient-based optimization reduces the number of function calls by several orders of magnitude. The case studies also show that adding curvature improves convergence behavior, allowing gradient-based optimization algorithms used with the FLORIS model to more reliably find better solutions to wind farm optimization problems.},
doi = {10.1177/0309524X17722000},
journal = {Wind Engineering},
number = 5,
volume = 41,
place = {United States},
year = 2017,
month = 8
}
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