How a Wind Turbine Shroud Can Adjust Its Blades to Control Power

This patent describes a wind turbine design where a ring-shaped casing around the main rotor has small, adjustable blades that can change their angle to control how much wind hits the rotor and how much power is generated.

What it covers

This patent describes a 'shrouded fluid turbine' that includes a main 'rotor' (the spinning blades) and a 'ringed airfoil' around it, which acts like a shroud or casing. This ringed airfoil is made up of many 'pivotable airfoil segments' (Claim 1), which are essentially small, adjustable blades. Each of these segments can 'rotate about an axis to change a pitch' (Claim 2), meaning their angle can be adjusted. A 'pitch control mechanism' (Claim 3) can change the angle of these segments, even 'continuously' during operation (Claim 4). By changing the angle of these shroud segments, the turbine can control the airflow to the main rotor, thereby managing its power output or reducing the impact of uneven wind, like 'wind shear' (Claim 19). For example, if the wind is too strong, the segments can be angled to reduce the airflow to the rotor, preventing over-speeding.

What it doesn't cover

• —Does not cover wind turbines that do not have a shroud or casing around their rotor.
• —Does not cover shrouded turbines where the shroud segments are fixed and cannot change their angle or 'pitch'.
• —Does not cover controlling turbine power solely by adjusting the pitch of the main rotor blades.
• —Does not cover systems where the entire ringed airfoil pivots as a single unit, rather than individual segments being adjustable.
• —Does not cover turbines where the shroud's pitch is only set once and not altered during operation.

The clever bit

The clever part is shifting the primary power control mechanism from the large, complex main rotor blades to smaller, individually adjustable segments on the surrounding shroud. This allows for fine-tuned control of airflow and can specifically address issues like wind shear by altering the shroud's pitch in different sections, making the turbine more adaptable.

Why it matters

Controlling the power output of wind turbines is crucial for efficiency and preventing damage in varying wind conditions. This invention offers a way to manage power and mitigate 'wind shear' — where wind speed changes significantly over the height of the rotor — without needing to adjust the large, heavy main rotor blades. This could lead to more stable and potentially more efficient wind energy generation, especially in turbulent environments.

Real-world examples

• 1.FloDesign Wind Turbine's ducted turbine prototypes
• 2.Advanced shrouded wind turbine designs
• 3.Turbines designed for urban or turbulent wind environments