Airborne Wind Energy Glider Tether Control for Load Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing airborne wind energy systems face challenges in ensuring operational safety and economic viability, particularly in varying wind conditions, with high loads during cross-wind flight and the need for automated operation across a wide range of wind conditions.
Innovation Solution
A method for operating an airborne wind energy system with a glider and tether, where wind conditions are monitored to switch between regular operation modes for maximum energy production, low wind operation modes for risk mitigation, and high wind operation modes, including transitional phases for safe and efficient energy harvesting, and reducing system efficiency by controlling tether tension, lift, and drag to avoid overloading.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the glider follows a high-lift flight pattern during the production phase to maximize energy production, then energy output is improved, but load on the tether increases causing safety risks
Solution Approach 1:
The patent implements dynamic operation modes that adjust the glider's flight pattern and lift generation based on real-time wind conditions. In regular operation mode, the system uses high-lift patterns for maximum energy production. When wind conditions exceed thresholds, the system transitions to safety modes with reduced lift and smaller flight patterns, dynamically adapting to balance energy output with tether load safety
Solution Approach 2:
The system changes operational parameters including flight pattern size, lift magnitude, and tether tension based on monitored wind conditions. By adjusting these parameters according to wind speed and direction, the system optimizes energy production within safe operational limits, preventing excessive tether loads while maintaining productivity
2Productivity
If the system operates automatically across a wide range of wind conditions to ensure economic viability, then operational continuity is improved, but operational safety risks increase
Solution Approach 1:
The patent implements a feedback control system that continuously monitors wind conditions and automatically adjusts operation mode accordingly. Wind sensors provide real-time data to the control mechanism, which transitions between regular operation mode and safety modes based on predetermined thresholds, ensuring both continuous operation and safety through closed-loop control
Solution Approach 2:
The system performs self-monitoring and self-adjustment of operational modes based on wind conditions. The automated control mechanism eliminates the need for manual intervention while maintaining safety through programmed response to wind threshold exceedances, enabling the system to serve itself in maintaining safe and continuous operation
3Reliability
If the system reduces efficiency by retaining tether tension above a threshold to avoid overloading, then safety is improved, but energy production decreases
Solution Approach 1:
The system applies partial action by using electrical machines to provide assisting force during specific phases of the flight pattern. During reel-in phase, electrical machines help pull the glider back, reducing the reliance on high tether tension. This partial mechanical assistance allows the system to maintain safety tension thresholds while recovering more energy during the production phase
4Productivity
If the glider velocity is increased to maintain airborne status during low wind conditions, then operational continuity is improved, but power output decreases
Solution Approach 1:
The system stores energy in the form of tether tension and glider velocity during periods of adequate wind conditions. This stored kinetic and potential energy is then utilized during low wind conditions to maintain the glider airborne without requiring high power output, effectively using preliminary energy accumulation to bridge periods of insufficient wind resource
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances operational safety and economic viability by optimizing energy production across different wind conditions, reducing the risk of system overload, and maintaining the glider airborne during low winds, ensuring continuous operation and minimizing manual intervention.
Implementation Method 1
producing energy by driving said electrical rotary machine via the tether using lift generated by said airfoil of said glider exposed to wind
Data Source
AI summary
Operating method for a system for airborne wind energy production, said system comprising a ground station, an airworthy glider with an airfoil, and a tether for connecting said glider with said ground station, said system being constructed and arranged for airborne wind energy production using lift generated by said airfoil exposed to wind, wherein a first operating phase of increasing free length of tether including flying said glider away from said ground station is repeatedly alternated with a second operating phase of decreasing free length of tether including flying said glider towards said ground station. The operating method according to the invention is characterized in that wind conditions are monitored, wherein at wind conditions below a predetermined minimum condition, said glider is pulled towards said ground station via said tether during at least a part of said second operating phase, thereby increasing velocity of said glider, wherein additional velocity is used to raise altitude of said glider during the following second operating phase.