Aerodynamic Parameter Identification for an Airborne Wind Energy Pumping System

Abstract Airborne Wind Energy refers to systems capable of harvesting energy from the wind by flying crosswind patterns with a tethered aircraft. Tuning and validation of flight controllers for AWE systems depends on the availability of reasonable a priori models. In this paper, aerodynamic coefficients are estimated from data gathered from flight test campaign using an efficient multiple experiments model based parameter estimation algorithm. Data fitting is performed using mathematical models based on full six degree of freedom aircraft equations of motion. Several theoretical and practical aspects as well as limitations are highlighted. Finally, both model selection and estimation results are assessed by means of R-squared value and confidence ellipsoids.

[1]  Rolf Rannacher,et al.  Model Based Parameter Estimation: Theory and Applications , 2015 .

[2]  Joel Andersson,et al.  A General-Purpose Software Framework for Dynamic Optimization (Een algemene softwareomgeving voor dynamische optimalisatie) , 2013 .

[3]  Victor M. Becerra,et al.  Optimal control , 2008, Scholarpedia.

[4]  Lorenz T. Biegler,et al.  On the implementation of an interior-point filter line-search algorithm for large-scale nonlinear programming , 2006, Math. Program..

[5]  H. Bock,et al.  A Multiple Shooting Algorithm for Direct Solution of Optimal Control Problems , 1984 .

[6]  Wubbo Ockels,et al.  Modeling, Simulation, and Testing of Surf Kites for Power Generation , 2008 .

[7]  Moritz Diehl,et al.  Numerical Trajectory Optimization for Airborne Wind Energy Systems Described by High Fidelity Aircraft Models , 2013 .

[8]  Moritz Diehl,et al.  Modeling of Airborne Wind Energy Systems in Natural Coordinates , 2013 .

[9]  Wubbo Ockels,et al.  Modeling and control of a kite on a variable length flexible inelastic tether , 2007 .

[10]  Weeratunge Malalasekera,et al.  An introduction to computational fluid dynamics - the finite volume method , 2007 .

[11]  Mario Zanon,et al.  Model Predictive Control of Rigid-Airfoil Airborne Wind Energy Systems , 2013 .

[12]  Lennart Ljung,et al.  System Identification: Theory for the User , 1987 .

[13]  J. Anderson,et al.  Fundamentals of Aerodynamics , 1984 .

[14]  Eugene A. Morelli,et al.  Practical Aspects of the Equation-Error Method for Aircraft Parameter Estimation , 2006 .

[15]  Moritz Diehl,et al.  Airborne Wind Energy: Basic Concepts and Physical Foundations , 2013 .

[16]  Mikhail Goman,et al.  State-Space Representation of Aerodynamic Characteristics of an Aircraft at High Angles of Attack , 1994 .

[17]  Jan Mulder,et al.  Accurate estimation of aircraft inertia characteristics from a single suspension experiment , 1987 .

[18]  M. L. Loyd,et al.  Crosswind kite power (for large-scale wind power production) , 1980 .

[19]  Moritz Diehl,et al.  Optimal control for minimizing power consumption during holding patterns for airborne wind energy pumping system , 2016, 2016 European Control Conference (ECC).