Wind Turbine Tower Damping via Predictive Load Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Wind turbines experience significant tower oscillations due to turbulence, sudden gusts, and inefficient damping, leading to mechanical strain and potential damage, with existing aerodynamic damping being reactive and not effectively preventing extreme loads.

Innovation Solution

A non-linear tower damping model is implemented using a control system that predicts tower deflection and load moments, generating variable damping coefficients to proactively control tower damping by adjusting blade pitch angles, thereby preventing extreme loads.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If aerodynamic damping is used to reduce tower oscillations, then tower vibrations are reduced under many circumstances, but the damping is reactive and only activates after oscillations have occurred, requiring the tower to be sturdy enough to sustain extreme loads

Engineering Contradiction:
Improvetower oscillationsVSAvoidtower structural integrity under extreme loads
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The control system performs preliminary action by predicting future tower deflections and oscillations before they occur. Using measured tower deflection, velocity, and acceleration data, the system forecasts upcoming extreme loads and activates damping control in advance, rather than reacting after oscillations have already occurred. This prevents the tower from experiencing extreme loads that would otherwise require overly sturdy construction.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system implements feedback control by continuously measuring tower deflection, velocity, and acceleration, comparing actual values against predicted values, and adjusting blade pitch angles in real-time. This closed-loop feedback mechanism enables the tower damping system to respond dynamically to changing wind conditions and oscillation patterns, optimizing damping effectiveness while reducing structural load requirements.

Inventive Principle:
Principle #23Feedback

2Object-affected harmful factors

If the rotor velocity is synchronized with the tower oscillations, then aerodynamic damping aids in reducing oscillations, but the tower may oscillate at a high rate causing mechanical strain and possible damage to the tower, generators and drivetrains

Engineering Contradiction:
Improvetower oscillationsVSAvoidmechanical strain on tower and drivetrain components
Core Design Contradiction:
Object-affected harmful factorsVSStrength

Solution Approach 1:

The system dynamically adjusts the damping control strategy based on real-time tower oscillation characteristics. When tower oscillation frequency approaches rotor velocity synchronization (resonance conditions), the control system modifies blade pitch commands to avoid amplifying oscillations. This dynamic adaptation prevents mechanical strain on tower and drivetrain components while maintaining oscillation reduction benefits.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The control system uses feedback from tower deflection, velocity, and acceleration sensors to detect resonance conditions. When synchronization between rotor velocity and tower oscillations is detected, the system adjusts blade pitch angles to reduce oscillation amplitude and prevent excessive mechanical strain on structural components.

Inventive Principle:
Principle #23Feedback

3Reliability

If a sturdy tower is used to sustain extreme loads until aerodynamic damping is activated, then tower structural integrity is maintained, but the cost of energy increases

Engineering Contradiction:
Improvetower structural integrityVSAvoidcost of energy
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The control system performs preliminary action by predicting extreme loads before they occur and activating damping control in advance. This prevents the tower from experiencing uncontrolled extreme loads, allowing the use of lighter, more cost-effective tower structures without compromising structural integrity or energy production economics.

Inventive Principle:
Principle #10Preliminary action

4Object-affected harmful factors

If a non-linear tower damping model with predictive control is implemented, then extreme loads are prevented and tower oscillations are reduced, but the system complexity increases

Engineering Contradiction:
Improveextreme loads on towerVSAvoidcontrol system complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The system replaces complex mechanical damping structures with a control-based approach using blade pitch adjustment. Instead of implementing physical dampers or mechanical shock absorbers on the tower, the system uses the existing aerodynamic forces on the blades to provide damping control, reducing mechanical complexity while achieving the same protective function.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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 solution effectively reduces tower oscillations and prevents mechanical strain by actively controlling damping, enhancing the durability of wind turbine components and reducing energy costs through predictive load management.

Implementation Method 1

aerodynamic damping which relies on the fact that the top of the tower constantly oscillates in the fore-aft direction. When the top of the tower moves upwind (or forward), the rotor thrust is increased. This increase in rotor thrust pushes the tower back downwind.

Methodology Applied
Scientific EffectAerodynamic damping: Damping

Data Source

PatentEP2963283B1Methods and systems to operate a wind turbine system
Publication Date: 2018.01.31 GENERAL ELECTRIC CO
  • EP2963283B1 patent drawingFigure 1
  • EP2963283B1 patent drawingFigure 2
  • EP2963283B1 patent drawingFigure 3

AI summary

A wind turbine system 10 is presented. The wind turbine system 10 includes a tower 14, a plurality of blades 24, a rotor 22 supported by the tower 14 and rotatably coupled to the plurality of blades 24, a control unit 28 programmed to predict a net energy of the tower 14 at one or more future points in time, and if the predicted net energy is within a design limit, then continue with baseline operating control models for normal operation of the wind turbine system 10, if the predicted net energy exceeds the design limit, then use a non-linear tower damping model to generate tower damping commands to control tower damping of the wind turbine system 10.