Repair Strategies for Wind Turbines

In-place bearing replacement method for wind turbine main shafts without disassembling the entire drive train. It involves using a crane to lift the shaft to a clearance height, removing the old bearing, installing a split bearing with separate semi-circular components, and then lowering the shaft back into position. This allows bearing replacement uptower without removing the entire drive train. A rotor lock prevents shaft rotation during lifting. The split bearing design allows disassembly and installation in sections.

Source

With the increasing capacity of wind turbines, key components including rotor diameter, tower height, and radius expand correspondingly. This heightened inertia extends response time pitch actuators during rapid speed variations occurring above rated speed. Consequently, turbines encounter significant output power oscillations complex structural loading challenges. To address these issues, this paper proposes a novel control strategy combining an effective estimation with inverse system method. The developed aims to stabilize rotational despite fluctuations. Central approach is aerodynamic torque using extended Kalman filter (EKF) applied drive train model. estimated then utilized compute at plane via differential Leveraging estimate, technique transforms nonlinear turbine dynamics into linearized, decoupled pseudo-linear system. linearization facilitates design more agile controller. Simulation outcomes demonstrate that proposed markedly enhances speed, diminishes oscillations, alleviates loads, notably base. These improvements bolster operational safety stability under above-rated ... Read More

Source

Repair device for wind turbine bearings with damaged teeth that enables maintaining torque transfer between the motor and the damaged bearing without replacing the entire bearing. The repair device has a carrier aligned with the damaged teeth and a gear train mounted on it. The gear train includes a drive gear connected to the motor, idler gears between the drive gear, and pinion gears meshed with the damaged and undamaged teeth of the bearing. This allows the motor torque to be transferred to the undamaged teeth instead of the damaged ones.

Source

Wind turbines experience significant vibrations due to fluctuating wind loads, which can impact structural integrity and operational efficiency. This study examines the effectiveness of Pendulum Tuned Mass Dampers (PTMDs) for mitigating these vibrations. Two types force inputs were analyzed: a sinusoidal function representing periodic fluctuations random simulating turbulent effects. Numerical simulations conducted evaluate influence mass ratios (0.01, 0.02, 0.05) damping (0.1, on vibration suppression. The results indicate that installation PTMD reduce from 45% 91% under varying operating conditions. optimum suppression up was achieved when ratio 0.02 0.01 excitation. A 0.05 also led decrease 54% in nacelle oscillations, confirming promoting stability. An optimal found effectively balance energy dissipation stability, preventing excessive oscillations maintaining system These findings confirm integrating enhance turbine performance by reducing fatigue loads extending lifespan. By optimizing parameters, engineers achieve better control, improving stability durability underscores impo... Read More

Source

Automated composite part repair system using a robot with interchangeable end effectors for inspection and repair tasks. The system allows robotic inspection, damage removal, repair patch placement, and surface preparation using an atmospheric plasma tool. The robot can switch between different end effectors like plasma preparation, imaging, scanning, and machining. It uses 3D modeling to coordinate actions with the part inside the cell. The plasma tool increases surface energy for bonding. The system enables automated composite part repair and verification.

Source

Abstract The sustainable development of the wind energy industry faces several challenges, one which is lack flexibility in adapting to increasing power system complexity. From farm operators perspective, means ability adjust generation patterns different constraints. However, current practice, curtailment strategies are primarily driven by regulatory restrictions and market-based economic factors. effects these on turbine loading, lifetime, their associated costs or benefits mostly overlooked. Currently, operators tools evaluate while also considering potentially conflicting component lifespan. In this sense, a condition monitoring (CMS) based an advanced shape sensing solution for blades being developed Fibersail. This work demonstrates capability Fibersails CMS deliver critical data assess impact terms fatigue loads deflection. By continuously tracking blade throughout turbines can make more informed operational decisions. enables transition active asset management, where strategically choose between Power Mode - maximizing production Lifetime minimizing wear ext... Read More

Source

Abstract Cost reduction within the operations & maintenance (O&M) phase plays a key role in reducing levelized cost of energy generated by offshore wind farms. While innovative technologies offer promising solutions, they also present significant financial risks for farm operators, as it is challenging to assess profitability technology integration. The simulation-based assessment concepts can facilitate identification their potential, support integration new technologies, and help prioritize research development efforts. In this study, we comparatively evaluate potential various O&M using simulation software OffshoreTIMES. Innovations four different application areas are investigated: (1) novel crew transfer vessel (CTV) designs, (2) crane-less (3) inspection drones, (4) rotor blade repair robots. To address diverse technological stages, each evaluated conservative near-present an optimistic future scenario. Additionally, combined scenarios simulated order gain insights into interactions between technologies. Our findings demonstrate that significantly enhance availabili... Read More

Source

Automated wind turbine blade repair system that uses laser scanning, CAD design, and robotics to improve blade repair efficiency and quality. The process involves scanning the blade surface to identify damage, creating a 3D model, analyzing the model to determine repair plan, then using robots to automatically repair the blade according to the plan. After repair, scanning is done again to verify the repair quality. This automated system replaces manual repairs and provides consistent, efficient blade repairs.

Source

Repair method for wind turbine blade tips that allows effective repair of blade damage, particularly when the web is damaged at the tip. The method involves cutting off the damaged blade tip section, creating new prefabricated parts to fit the cut surfaces, and bonding them back together. This allows internal repairs instead of just cosmetic fixes. The prefabricated parts are made by layering fiberglass cloth and resin on molds. The web preform is bonded to the cut web, then the leeward side preform is bonded to the leeward cut, followed by the windward preform. Leading edge corner preforms are used to join the windward and leeward parts. The outer surface is trimmed to complete the repair. This internal repair improves quality, uses the full blade, reduces waste, and avoids common issues of effectively repairing web damage at wind turbine blade tips.

Source

Repairing composite parts like turbine blades without removing the damaged section and without using pre-impregnated patches. Instead, the method involves: 1) Removing the damaged composite material to create a hollowed-out section. 2) Producing a 3D woven fiber filling preform to fit in the hollowed-out section. 3) Placing the filling preform in the hollowed-out section, sealing it, and applying pressure to bond the preform to the existing composite. 4) Curing the preform resin to complete the repair. The method allows custom-shaped repairs without requiring full part replacement or pre-impregnated patches. It uses 3D woven fibers to match the original composite weave.

Source

Automated method for repairing wind turbine blades that significantly reduces labor consumption by transferring as many steps as possible to automated intelligent systems and equipment. The method involves using cleaning devices to automatically clean the blades, automated inspection tools to assess damage severity, and robotics for repair tasks like applying adhesives and shaping composites. This allows automated systems to handle tasks like blade cleaning, scar identification, and surface smoothness assessment, while leaving more complex repairs like crack filling and composite shaping to robotic systems.

Source

Reinforcing repair method for the trailing edge of wind turbine blades to address cracking and damage caused by fatigue loads. The repair method involves identifying the trailing edge form (thick blunt, transitional wedge, or pointed) based on the blade's manufacturing process, and then repairing bonding cracking damage using specific parameters for overlap width, thickness, length, and slope. The repair involves injecting structural adhesive into the crack, followed by mold closing and curing.

Source

Repairing single crystal turbine blades using a laser swing composite power modulation method to improve repair efficiency and reduce risk. The method involves using a laser with reciprocating swing motion during repair to expand the repair area and reduce the number of repairs. Power modulation is used to adjust laser power in the target repair area to increase temperature gradient and flatten the molten pool for stable single crystal epitaxial growth.

Source

Blade repair method for wind turbine blades that allows efficient and effective repair of damaged blades without compromising performance. The repair involves identifying the damaged area, setting a cutting range and repair mode based on the damage, then cutting and repairing the blade. The repair can involve inserting rivets, screws, or filler into the cutout, depending on the damage type. This allows restoration of conductivity, erosion resistance, or structural integrity. The repair is tailored to the specific damage to optimize repair quality.

Source

Method for repairing defects in main beam and trailing edge of wind turbine blades that enables faster, easier and higher quality repairs compared to conventional methods. The repair process involves tearing off the damaged glass fiber layer, grinding residual defects and interfaces, and then layering on new glass fiber and resin to replace the repaired section. This allows larger area and layer-by-layer grinding instead of manual polishing, reducing skill requirements and time compared to layer-by-layer repair.

Source

Repairing wind turbine blade cementitious structures to improve shear strength and prevent failure. The repair involves applying a reinforcement layer to cover the original bond area between the blade members after removing the failed cement. This reinforcement layer is cured before rebonding the members. The reinforcement layer strengthens the repaired cementitious structure and prevents shear failure compared to direct rebonding.

Source

Repairing wind turbine blade leading edges to mitigate erosion using an aerial repair system that lifts and positions a repair device against the blade. The system has a propulsion system to generate a lateral force pressing the repair device into blade engagement. This allows precise control of the repair position. The repair device can move along the blade edge while repairing, and the lifting mechanism allows rotation of the device relative to the blade. The lateral force emulates self-weight contact to prevent rotor torque. The aerial repair reduces outage time compared to ground repairs.

Source

Repairing composite turbine blade tips without machining by using foils to fill the damaged area and then curing the refill material. The blade is positioned in a tool and foils are attached to the damaged tip region on the inner and outer surfaces. The foils extend beyond the damaged area. The foils are filled with a paste or fluid refill material like uncured resin. Excess material is trimmed. The blade is then cured. The foils are removed after curing. This avoids the need for machining after curing since the foil dimensions define the repair area.

Source

Method for repairing damaged leading or trailing edges of metal turbine blades to prevent failure and improve turbine life. The repair involves removing the damaged area to create a cutout, inserting a form-fitting replacement part into the cutout, and connecting the replacement part to the blade. The key innovation is to avoid undercuts when creating the cutout. Instead, recesses are formed on the blade walls that are offset from each other. This allows the replacement part to be inserted without requiring undercuts that would make removal difficult. Once inserted, the replacement part is bonded to the blade to complete the repair.

Source

A method to repair subsurface defects in wind turbine blade shells without disrupting aerodynamics and reducing repair time compared to conventional methods. The repair involves detecting the location and boundary of the subsurface defect from the outside using non-destructive inspection techniques. Then, a fill hole is drilled into the defect from the outer surface close to the boundary. This allows filling the defect with adhesive without contamination or extended surface preparation. The fill hole is subsequently sealed and the blade restored to service. This targeted subsurface repair avoids extensive abrasive grinding and reapplying laminate layers.

Source