Wind Turbine Rotor-Stall Prevention Control
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Solution Overview
Problem
Current wind turbine control systems fail to maintain optimal operation and prevent aerodynamic stall, particularly in low air density conditions, leading to reduced energy transfer and power degradation.
Innovation Solution
A control system that adjusts blade pitch angles to maintain a minimum pitch greater than or equal to a calculated minimum angle based on modeled aerodynamic performance, using sensor data for rotor and wind speed measurements to prevent stall conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the control system decreases blade pitch to increase angle of attack in response to perceived power loss, then energy transfer from wind is expected to increase, but aerodynamic stall condition is worsened and flow separation increases
Solution Approach 1:
The control system proactively maintains blade pitch at or above a calculated minimum pitch angle threshold before stall conditions fully develop. By using a stall prevention model that predicts impending stall based on current operating conditions (wind speed, rotor speed, air density), the system takes preliminary action to adjust pitch and maintain the rotor-stall margin, preventing the harmful feedback loop where decreasing pitch worsens stall conditions
Solution Approach 2:
The system implements feedback control by continuously monitoring actual power output and comparing it to expected power based on wind conditions and rotor speed. When the actual power deviates from expected power indicating potential stall, the feedback loop adjusts blade pitch to maintain the minimum pitch angle, correcting the deviation and preventing further deterioration of aerodynamic performance
2Productivity
If blade size is increased to increase energy capture, then energy transfer capability is improved, but control difficulty and risk of aerodynamic stall increase
Solution Approach 1:
The control system dynamically adjusts operating parameters (blade pitch angle, rotor speed) based on real-time conditions including wind speed, air density, and rotor position. By continuously optimizing these parameters and maintaining operation above the minimum pitch angle threshold, the system enables larger blades to operate efficiently across varying conditions without entering stall, thus improving ease of operation while maintaining high energy capture capability
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 reduces or eliminates aerodynamic stall, ensuring continuous optimal energy capture and power production across varying wind conditions.
Implementation Method 1
Blades on these rotors transform wind energy into a rotational torque or force that drives one or more generators
Implementation Method 2
Aerodynamic stall causes a decrease in lift and an increase in drag coefficients for a wind turbine blade
Implementation Method 3
Pitch setting of the blades (i.e. the angle of attack of the airfoil shaped blade), provides one of the parameters utilized in wind turbine control
Implementation Method 4
one or more generators that may be rotationally coupled to the rotor through a gearbox. The gearbox steps up the inherently low rotational speed of the turbine rotor for the generator to efficiently convert mechanical energy to electrical energy
Data Source
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AI summary
A method 400 for operating a wind turbine 100 is based on providing a wind turbine 100 that includes a control system 112 programmed to adjust a blade pitch angle of one or more rotor blades 108 without knowledge of rotor blade efficiency. A blade pitch angle of one or more rotor blades 108 is adjusted in response to the current conditions experienced by the wind turbine 100 to provide a blade pitch angle that is greater than or equal to a blade pitch angle necessary to maintain a predetermined minimum rotor stall margin according to modeled aerodynamic performance of the rotor blades 108 such that continuous operation of the wind turbine 100 is maintained without transitions to the stalled mode.