Automatic Control of Pumping Cycles for the SkySails Prototype in Airborne Wind Energy

Part of the Green Energy and Technology book series (GREEN)


The efficient and economic operation of tethered kites for accessing highaltitude winds as a renewable source of energy requires fully automated setups. During the last decade the SkySails kite systems have been developed for applications in marine propulsion and energy generation. In this chapter we give a descriptive overview of the flight control of the tethered kite and of the control of the tether reeling speed leading to pumping cycles for energy generation. This chapter focuses on the discussion and justification of the overall design choices, functional dependencies and the presentation of the complete system in a self-contained way. For details of the mathematical modeling and control theoretical aspects references for further reading are provided. After an introduction, the dynamical model for the tethered dynamics is briefly summarized. Subsequently, the estimation and sensor system is presented. Then, the control approach is discussed and the parts of the control system are reviewed in detail. Finally the implemented system is briefly compared to other control approaches.


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Michael Erhard gratefully acknowledges funding from ERC ST HIGH-WIND (259166) and valuable discussions within this collaboration.


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© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.SkySails GmbHHamburgGermany
  2. 2.Systems Control and Optimization Laboratory, Department of Microsystems Engineering (IMTEK)University of FreiburgFreiburgGermany

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