The wind energy industry is continuously improving their operational and maintenance practice for reducing the levelized costs of energy. Anticipating failures in wind turbines enables early warnings and timely intervention, so that the costly corrective maintenance can be prevented to the largest extent possible. It also avoids production loss owing to prolonged unavailability. One critical element allowing early warning is the ability to accumulate small-magnitude symptoms resulting from the gradual degradation of wind turbine systems. Inspired by the cumulative sum control chart method, this study reports the development of a wind turbine failure detection method with such early warning capability. Specifically, the following key questions are addressed: what fault signals to accumulate, how long to accumulate, what offset to use, and how to set the alarm-triggering control limit. We apply the proposed approach to 2 years’ worth of Supervisory Control and Data Acquisition data recorded from five wind turbines. We focus our analysis on gearbox failure detection, in which the proposed approach demonstrates its ability to anticipate failure events with a good lead time.
more »
« less
A Safety‐Aware Framework for Offshore Wind Turbine Maintenance
In this paper, we suggest a framework for determining the best operation and maintenance strategies for offshore wind turbines. The framework takes into account both quantitative and qualitative data gathered from the wind turbines. The proposed framework consists of a simulation‐optimization approach for designing, planning, and scheduling maintenance operations for offshore wind farms and finding the optimal intervention solution for minimizing costs while keeping a high availability of wind turbines and guaranteeing safety standards for workers. Several parameters and constraints are addressed to account for the realistic complexity of the problem, such as weather conditions, resource cost, and maintenance duration. A numerical case study focusing on offshore wind turbine blade maintenance is presented to demonstrate the implementation of the proposed framework. The example simulates realistic defect progression scenarios, stratified by severity level, and incorporates empirically grounded estimates of failure rates, repair costs, technician requirements, and vessel logistics. The study illustrates how the simulation‐optimization approach integrates economic considerations, resource constraints, and safety risk factors to support data‐informed maintenance scheduling decisions under uncertainty.
more »
« less
- Award ID(s):
- 2230630
- PAR ID:
- 10662995
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Wind Energy
- Volume:
- 28
- Issue:
- 12
- ISSN:
- 1095-4244
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
null (Ed.)This work focuses on the optimization of performance and profitability of a wind farm carried out by means of an economic model and Reynolds-Averaged Navier-Stokes (RANS) simulations of wind turbine wakes. Axisymmetric RANS simulations of isolated wind turbine wakes are leveraged with a quadratic super-positioning model to estimate wake interactions within wind farms. The resulting velocity field is used with an actuator disk model to predict power production from each turbine in the wind farm. Design optimization is performed by considering a site in North Texas, whose wind resource statistics are obtained from a meteorological tower. The RANS solver provides capabilities to simulate different incoming wind turbulence intensities and, hence, the wind farm optimization is performed by taking the daily cycle of the atmospheric stability into account. The objective functional of the optimization problem is the levelized cost of energy (LCoE) encompassing capital cost, operation and maintenance costs, land cost and annual power production. At the first level of the optimization problem, the wind farm gross capacity is determined by considering three potential turbine types with different rated power. Subsequently, the optimal wind farm layout is estimated by varying the uniform spacing between consecutive turbine rows. It is found that increasing turbine rated power, the wind farm profitability is enhanced. Substituting a wind farm of 24 turbines of 2.3-MW rated power with 18, 3-MW turbines could reduce the LCoE of about 1.56 $/MWh, while maintaining a similar gross capacity factor. The optimization of the spacing between turbine rows was found to be sensitive to the land cost. For a land cost of 0.05 $/m2, the layout could be designed with a spacing between 6 to 15 rotor diameters without any significant effect on the LCoE, while an increased land cost of 0.1 $/m2 leads to an optimal spacing of about 6 rotor diameters.more » « less
-
Accurate wave height measurements are critical for offshore wind farm operations, marine navigation, and environmental monitoring. Wave buoys provide essential real-time data; however, their reliability is compromised by harsh marine conditions, resulting in frequent data gaps due to sensor failures, maintenance issues, or extreme weather events. These disruptions pose significant risks for decision-making in offshore logistics and safety planning. While numerical wave models and machine learning techniques have been explored for wave height prediction, most approaches rely heavily on historical data from the same buoy, limiting their applicability when the target sensor is offline. This study addresses these limitations by developing a virtual wave buoy model using a network-based data-driven approach with Random Forest Regression (RFR). By leveraging wave height measurements from surrounding buoys, the proposed model ensures continuous wave height estimation even in the case of malfunctioning physical sensors. The methodology is tested across four offshore sites, including operational wind farms, evaluating the sensitivity of predictions to buoy placement and feature selection. The model demonstrates high accuracy and incorporates a k-nearest neighbors (kNN) imputation strategy to mitigate data loss. These findings establish RFR as a scalable and computationally efficient alternative for virtual sensing, thereby enhancing offshore wind farm resilience, marine safety, and operational efficiency.more » « less
-
Abstract The U.S. offshore wind industry can expect higher costs due to the lack of domestic experience with offshore wind technology. A key factor of the capital expenditure related to offshore wind farms is the cost of the support structures of offshore wind turbines. Therefore, improvements to the reliability of support structures under ultimate and fatigue loading conditions will help reduce the levelized cost of energy of offshore wind. This study presents a framework that accounts for the wind directionality by assuming a distinct and independent wind speed distribution per each wind direction and investigates its effect on the fatigue life of offshore wind turbine support structures. A monopile support structure in a potential wind site close to a National Oceanic and Atmospheric Administration buoy in the north-eastern US waters is used in this study. Fatigue damage assessment is performed for the normal operational condition of wind turbine, and the results are presented considering both cathodic protection and free corrosion conditions at the mudline level of the monopile. The location and extent of the predicted fatigue damages are found to vary due to accounting for the wind directionality.more » « less
-
Battery energy storage systems (BESS) are increasingly deployed in microgrids due to their benefits in improving system reliability and reducing operational costs. Meanwhile, advanced small modular reactors (SMRs) offer many advantages, including relatively small physical footprints, reduced capital investment, and the ability to be sited in locations not possible for larger nuclear plants. In this paper, we propose a bi-level operational planning model that enables microgrid planners to determine the optimal BESS size and technology while taking into account the optimal long-term (a yearly simulation with a 15-min resolution) operations of a microgrid with SMRs and wind turbines. Case studies are performed using realistic BESS and grid data for two BESS technologies, i.e., Li-Ion battery and compressed air energy storage. Numerical results show the effectiveness of the proposed bi-level model. The pros and cons of the two BESS technologies are also revealed.more » « less
An official website of the United States government

