Wind Turbine Rotor Blade Tip Offset Upstream

Solution Overview

Problem

Existing wind turbines face challenges in strong winds, where blade flexing and potential contact with the tower can lead to accidents and equipment damage, and current solutions either increase production costs with stiffer materials or reduce efficiency with tilted rotors.

Innovation Solution

A wind turbine system featuring a coned hub assembly with rotor blades offset upstream from the plane of rotation, reducing blade flexing and contact risk while maintaining efficiency by using a combination of pitched hub and contoured, forward-pitched rotor blades.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If stiffer blade materials are used to reduce blade flexing, then blade reliability is improved, but manufacturing cost increases and component loading increases

Engineering Contradiction:

Improveblade reliabilityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The blade tips are pre-positioned upstream of the plane of rotation before the rotor operates in strong winds. This preliminary positioning creates a safety margin that prevents tower contact before it can occur, eliminating the need for stiffer materials to resist flexing during operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Instead of increasing blade stiffness in the material dimension, the solution moves to the spatial dimension by offsetting blade tips upstream. This dimensional shift resolves the contradiction by addressing the contact risk through position rather than material property changes.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Reliability

If stiffer blade materials are used to reduce blade flexing, then blade reliability is improved, but the weight of blades increases causing greater loading on turbine components

Engineering Contradiction:

Improveblade reliabilityVSAvoidblade weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The blade tips are pre-positioned upstream of the plane of rotation before the rotor operates in strong winds. This preliminary positioning creates a safety margin that prevents tower contact before it can occur, eliminating the need for stiffer materials to resist flexing during operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Instead of increasing blade stiffness in the material dimension, the solution moves to the spatial dimension by offsetting blade tips upstream. This dimensional shift resolves the contradiction by addressing the contact risk through position rather than material property changes.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Reliability

If a tilted rotor is used to shift blade tips away from the tower, then blade reliability is improved, but system efficiency decreases due to uneven wind contact

Engineering Contradiction:

Improveblade reliabilityVSAvoidsystem efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The blade tips are pre-positioned upstream of the plane of rotation before the rotor operates in strong winds. This preliminary positioning creates a safety margin that prevents tower contact before it can occur, eliminating the need for stiffer materials to resist flexing during operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Instead of increasing blade stiffness in the material dimension, the solution moves to the spatial dimension by offsetting blade tips upstream. This dimensional shift resolves the contradiction by addressing the contact risk through position rather than material property changes.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

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

The system effectively prevents rotor blade contact with the tower during strong winds, reduces loads on turbine components, and enhances system efficiency without the need for heavier, stiffer blades, thereby minimizing accidents and equipment damage.

Implementation Method 1

wind pressure exerted against the blades may cause an elastic rearward flexing of the blades

Methodology Applied

Scientific EffectWind pressure: Pressure Increase

Implementation Method 2

wind pressure exerted against the blades may cause an elastic rearward flexing of the blades

Methodology Applied

Scientific EffectElastic flexing: Elasticity

Data Source

PatentUS8714928B2Rotor assembly for a wind turbine and method of assembling the same

Publication Date: 2014.05.06 GE INFRASTRUCTURE TECH LLC

AI summary

A rotor assembly is provided that includes a hub rotatable about an axis of rotation. The assembly also includes a plurality of rotor blades spaced circumferentially about the hub. Each of said rotor blades extends from a blade root to a blade tip such that said plurality of blades are rotatable through a plane of rotation extending about said axis of rotation, said plane of rotation is defined as substantially perpendicular to said axis of rotation, wherein each of said blade roots is coupled to said hub, wherein each of said blade tips is offset a distance upstream from said plane of rotation.