Sensitivity Analysis of Wind Plant Performance to Key Turbine Design Parameters: A Systems Engineering Approach

Abstract

This paper introduces the development of a new software framework for research, design, and development of wind energy systems which is meant to 1) represent a full wind plant including all physical and nonphysical assets and associated costs up to the point of grid interconnection, 2) allow use of interchangeable models of varying fidelity for different aspects of the system, and 3) support system level multidisciplinary analyses and optimizations. This paper describes the design of the overall software capability and applies it to a global sensitivity analysis of wind turbine and plant performance and cost. The analysis was performed using three different model configurations involving different levels of fidelity, which illustrate how increasing fidelity can preserve important system interactions that build up to overall system performance and cost. Analyses were performed for a reference wind plant based on the National Renewable Energy Laboratory's 5-MW reference turbine at a mid-Atlantic offshore location within the United States. Three software configurations were used: 1) a previously published wind plant cost model using simplified parametric scaling relationships, 2) an integrated set of wind turbine and plant engineering and cost models that use a "bottom-up" approach to determine overall wind plant performance and cost metrics, and 3) the second set of models plus the addition of a plant layout and flow model for calculation of energy production. Global sensitivity analysis was performed on each analysis set with respect to key wind turbine configuration parameters including rotor diameter, rated power, hub height, and maximum tip speed. The analyses show how the latter approaches capture important coupling throughout the wind plant in a way that has not previously been achieved. In addition, while deficiencies even in the newer model set are readily identifiable, the flexibility of the new framework shows how extension and gradual buildup of model fidelity for various parts of the system provide a powerful tool that enables analysis for an ever-expanding set of wind energy research and design problems.

Optimization of wind plant layouts using an adjoint approach

“…Simulations were performed using the WindSE code that will be made available through NREL's WISDEM software tool (Dykes et al, 2014), and can be accessed at https://nwtc. nrel.gov/WISDEM.…”

“…This gradient-based approach, made possible by automated adjoint derivations, yields an efficient, high-fidelity, and high-dimensional wind plant optimization framework. The software is part of the National Renewable Energy Laboratory Wind-Plant Integrated System Design and Engineering Model (WISDEM ™ ) (Dykes et al, 2014), which provides a modular framework for comprehensive analysis and optimization of wind plant designs. Through the use of a higher-fidelity 3-D RANS flow model and gradient-based adjoint optimization, WindSE is able to provide optimized layouts with arbitrary topological complexity at relatively low computational cost, while at the same time more accurately capturing turbulent flow effects present in real wind plants.…”

Combined preliminary–detailed design of wind turbines

“…Most of these studies initially focused on the sole blade design problem, as, for example, in Maalawi and Badr (2003), Jureczko and Pawlak (2005), and Xudong et al (2009). Integrated tools appeared later, leading to the development of the packages FOCUS from the Energy Research Centre of the Netherlands (ECN) (Duineveld, 2008), HAWTOPT from Danmarks Tekniske Universitet (DTU) (Døssing, 2011) and WISDEM from the National Renewable Energy Laboratory (NREL) and Sandia National Laboratories in the USA (Dykes et al, 2014). In parallel, the multi-disciplinary research code Cp-Max (Code for Performance Maximization) was developed integrating a high-fidelity aeroelastic simulator together with optimization algorithms, here again evolving from a mostly structural sizing code to a more comprehensive optimization environment (Bottasso et al, 2011(Bottasso et al, , 2013(Bottasso et al, , 2015.…”

Understanding the Benefits and Limitations of Increasing Maximum Rotor Tip Speed for Utility-Scale Wind Turbines

“…The methodology builds upon that described in [8][9][10]. Rotor aerodynamic performance was estimated using blade element momentum theory with a novel solution approach that enables usage in gradient-based optimization applications [11], and blade structural analysis was done using beam finite element theory and classical laminate theory.…”