What causes blade damage?

Blade damage on wind turbines can result from a variety of factors, both external and internal. As the global blade repair spend continues to rise, it’s crucial to understand these common causes and delve into their specifics.

During operation, the systems are exposed to various environmental influences that they must to withstand. These include:

• Erosion: High-speed winds carrying abrasive particles such as sand, rain, and hail can erode the leading edge of turbine blades, resulting in material loss and reduced aerodynamic efficiency.
• Lightning strikes: Wind turbine blades, being tall structures, are susceptible to lightning strikes during thunderstorms. Despite the IEC61400-24 lightning protection standard, wind turbines equipped with lightning protection systems are still vulnerable to strikes. These strikes can cause surface damage, including burns, pitting, and melting, compromising the structural integrity of the blades.

 

Lightning strike alert – Know when your assets have been struck by lightning

 

• Ice accretion: In cold climates, ice can accumulate on turbine blades during freezing conditions. The added weight and imbalance caused by ice accretion can strain the blades and lead to surface damage when the ice sheds.

There are also factors during operation that can cause lasting stress and damage to turbine components, such as:

• Fatigue: Repeated and cyclic loading on the blades during operation can lead to fatigue cracks, especially near critical areas such as the blade root or blade attachment points.
• Overloading: Turbine blades can experience overloading due to high wind speeds or sudden gusts, leading to excessive bending and deformation, causing structural damage.
• Resonance: Vibrations and resonance within the turbine system, particularly at certain wind speeds, can lead to stress concentration in the blades, potentially causing cracks and other damage.
• Blade misalignment: Improper alignment of the blades due to manufacturing defects or installation errors can cause uneven stress distribution, leading to premature wear and damage.

 

Get notified when your blades are misaligned

Design or production-related factors that negatively influence wind turbine operation cannot be ruled out, including:

• Material defects: Flaws or impurities in the materials used for blade construction can weaken the structure and make it more susceptible to damage.
• Design flaws: Inadequate design considerations, such as insufficient reinforcement in critical areas or inadequate aerodynamic profiles, can lead to premature fatigue and failure of the blades.
• Quality control issues: Poor manufacturing processes or lack of quality control measures can result in inconsistencies in blade construction, leading to vulnerabilities and potential failure points.

Inadequate maintenance or inspection can allow minor damage to develop into major, costly issues. For example:

• Lack of maintenance: Inadequate or irregular maintenance can lead to the accumulation of minor damages that can exacerbate over time, leading to more severe issues.
• Inspection failures: Ineffective inspection techniques or failure to detect early signs of damage during routine inspections can result in undetected blade defects, which may progress to more serious damage over time.

Addressing these factors through proactive maintenance, rigorous inspection protocols, and continuous monitoring can help minimize blade damage and ensure the safe and reliable operation of wind turbines. Our unique monitoring system supports wind turbine operators by continuously monitoring blade condition and notifying them of any changes or damage promptly.

Continuous monitoring pays off. Are you already staying informed about your rotor blades’ condition? For more details, contact our sales team.