Wind Turbine Blade Control via Rain Drop Size Estimation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Wind turbine blades suffer mechanical damage from precipitation, leading to costly repairs and reduced power output, as existing methods either stop the turbine or reduce rotation speed, both resulting in inefficiencies.

Innovation Solution

A method for controlling wind turbines that estimates rain drop size and precipitation intensity to determine if a reduced operation mode is necessary, limiting the angular rotation speed below a threshold to minimize erosion while maintaining energy production.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the wind turbine is stopped or rotation speed is reduced to prevent blade damage from rain, then blade mechanical damage is reduced, but power output is reduced

Engineering Contradiction:
Improveblade mechanical damage resistanceVSAvoidpower output
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The control method changes operational parameters (rotation speed limits) based on measured environmental parameters (rain drop size and precipitation intensity). By dynamically adjusting the rotation speed threshold according to actual rain conditions, the system prevents unnecessary shutdowns while protecting blades during high-risk conditions, thus resolving the contradiction between reliability and productivity

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The system uses sensors to continuously measure rain drop size and precipitation intensity, feeding this information back to the control device which then adjusts the rotation speed accordingly. This closed-loop feedback mechanism enables the turbine to operate at optimal speeds based on real-time weather conditions, maintaining power output when safe and preventing damage when necessary

Inventive Principle:
Principle #23Feedback

2Reliability

If the wind turbine is stopped or rotation speed is reduced to prevent blade damage from rain, then blade mechanical damage is reduced, but energy production is reduced

Engineering Contradiction:
Improveblade mechanical damage resistanceVSAvoidenergy production loss
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The system dynamically changes the rotation speed parameter based on measured rain characteristics. By establishing rotation speed thresholds that correlate with safe operating conditions during precipitation, the turbine maintains energy production when rain conditions are benign while limiting speed only when damage risk is high, thus minimizing energy loss while protecting blades

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

Instead of complete shutdown during all precipitation events, the system applies partial action by limiting rotation speed to a threshold value that still allows some energy production. This partial operation mode reduces blade stress exposure during light to moderate rain while maintaining partial power output, reducing overall energy loss compared to full shutdown

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP3542054B1Controlling wind turbine based on rain drop size
Publication Date: 2021.09.29 VESTAS WIND SYSTEMS AS
  • EP3542054B1 patent drawingFigure 1
  • EP3542054B1 patent drawingFigure 2
  • EP3542054B1 patent drawingFigure 3

AI summary

There is presented a method (320) for controlling a wind turbine (100), wherein said wind turbine comprises a wind turbine rotor (102) with one or more blades (103), wherein the wind turbine has a rated angular rotation speed (214) of the wind turbine rotor, said method comprising providing (322) an estimated drop size (324) of rain drops impinging on the one or more blades, determining (326) whether an entry criterion for operation according to a reduced mode is fulfilled, wherein said determining is based at least partially on the estimated drop size (324), controlling (328) the wind turbine according to the reduced mode if the entry criterion is fulfilled, wherein in the reduced mode an angular rotation speed of the wind turbine rotor is limited below an angular rotation speed threshold (216), wherein the angular rotation speed threshold is smaller than the rated angular rotation speed of the wind turbine.