scholarly journals Passive Acoustic Detection of Wind Turbine In-Flow Conditions for Active Control and Optimization

2012 ◽  
Author(s):  
Nathan E. Murray
Keyword(s):  
Wind Turbine ◽  
Active Control ◽  
Acoustic Detection ◽  
Flow Conditions ◽  
Passive Acoustic

Prediction of wind turbine blade trailing edge noise under various flow conditions for a passive damage detection system

2021 ◽  
Vol 263 (2) ◽  
pp. 4079-4087
Author(s):  
Murat Inalpolat ◽  
Caleb Traylor
Keyword(s):  
Structural Health Monitoring ◽  
Wind Turbine ◽  
Turbine Blade ◽  
Health Monitoring ◽  
Detection System ◽  
Wind Turbine Blade ◽  
Flow Conditions ◽  
Trailing Edge ◽  
Structural Health ◽  
Acoustic Spectra

Noise generated by turbulent boundary layer over the trailing edge of a wind turbine blade under various flow conditions is predicted and analyzed for structural health monitoring purposes. Wind turbine blade monitoring presents a challenge to wind farm operators, and an in-blade structural health monitoring system would significantly reduce O&M costs. Previous studies into structural health monitoring of blades have demonstrated the feasibility of designing a passive detection system based on monitoring the flow-generated acoustic spectra. A beneficial next step is identifying the robustness of such a system to wind turbine blades under different flow conditions. To examine this, a range of free stream air velocities from 5 m/s to 20 m/s and a range of rotor speeds from 5 rpm to 20 rpm are used in a reduced-order model of the flow-generated sound in the trailing edge turbulent boundary layer. The equivalent lumped acoustics sources are predicted based on the turbulent flow simulations, and acoustic spectra are calculated using acoustic ray tracing. Each case is evaluated based on the changes detected when damage is present. These results can be used to identify wind farms that would most benefit from this monitoring system to increase efficiency in deployment of turbines.

Fish Bioacoustics and Behavior: Passive Acoustic Detection and the Application of a Closed-Circuit Rebreather for Field Study

2001 ◽  
Vol 35 (2) ◽  
pp. 19-28 ◽  
Author(s):  
Phillip S. Lobel
Keyword(s):  
Behavioral Ecology ◽  
Daily Basis ◽  
Open Circuit ◽  
Acoustic Detection ◽  
Ecological Processes ◽  
Detection Technology ◽  
Scientific Goal ◽  
Species Specific ◽  
Passive Acoustic ◽  
And Behavior

The simple thesis of this paper is that using rebreathers to study fish behavioral ecology, especially bioacoustics, is well worth the expense and additional training required. The scientific goal of my bioacoustic research is to determine which fishes produce species-specific sound patterns exclusively with explicit acts of courtship and mating. This provides scientific insight into evolutionary and ecological processes and also provides data necessary to develop the passive acoustic detection technology for monitoring fish reproduction. When used on a daily basis, rebreathers, in my experience, are economical and as practical as open circuit scuba. This is based both on the costs of diving as well as the efficiency of gathering useful data. The use of open circuit SCUBA while conducting acoustic recordings results in a loss of at least 40% of the data due to the bubble noise from a divers breathing. Rebreathers also provide extended bottom time, especially in shallow water, which enhances a diver's ability to observe fish and gather acoustic-behavioral data.

scholarly journals Assessment of load reduction capabilities using passive and active control methods on a 10MW-scale wind turbine

2018 ◽  
Vol 1037 ◽  
pp. 032042 ◽  
Author(s):  
Dimitris I. Manolas ◽  
Giannis P. Serafeim ◽  
Panagiotis K. Chaviaropoulos ◽  
Vasilis A. Riziotis ◽  
Spyros G. Voutsinas
Keyword(s):  
Wind Turbine ◽  
Active Control ◽  
Load Reduction ◽  
Control Methods

scholarly journals Correlations of power output fluctuations in an offshore wind farm using high-resolution SCADA data

2021 ◽  
Vol 6 (4) ◽  
pp. 997-1014
Author(s):  
Janna Kristina Seifert ◽  
Martin Kraft ◽  
Martin Kühn ◽  
Laura J. Lukassen
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Power Output ◽  
Wind Farm ◽  
Offshore Wind ◽  
Offshore Wind Farm ◽  
Flow Conditions ◽  
Output Fluctuations ◽  
Power Difference ◽  
Time Correlations

Abstract. Space–time correlations of power output fluctuations of wind turbine pairs provide information on the flow conditions within a wind farm and the interactions of wind turbines. Such information can play an essential role in controlling wind turbines and short-term load or power forecasting. However, the challenges of analysing correlations of power output fluctuations in a wind farm are the highly varying flow conditions. Here, we present an approach to investigate space–time correlations of power output fluctuations of streamwise-aligned wind turbine pairs based on high-resolution supervisory control and data acquisition (SCADA) data. The proposed approach overcomes the challenge of spatially variable and temporally variable flow conditions within the wind farm. We analyse the influences of the different statistics of the power output of wind turbines on the correlations of power output fluctuations based on 8 months of measurements from an offshore wind farm with 80 wind turbines. First, we assess the effect of the wind direction on the correlations of power output fluctuations of wind turbine pairs. We show that the correlations are highest for the streamwise-aligned wind turbine pairs and decrease when the mean wind direction changes its angle to be more perpendicular to the pair. Further, we show that the correlations for streamwise-aligned wind turbine pairs depend on the location of the wind turbines within the wind farm and on their inflow conditions (free stream or wake). Our primary result is that the standard deviations of the power output fluctuations and the normalised power difference of the wind turbines in a pair can characterise the correlations of power output fluctuations of streamwise-aligned wind turbine pairs. Further, we show that clustering can be used to identify different correlation curves. For this, we employ the data-driven k-means clustering algorithm to cluster the standard deviations of the power output fluctuations of the wind turbines and the normalised power difference of the wind turbines in a pair. Thereby, wind turbine pairs with similar power output fluctuation correlations are clustered independently from their location. With this, we account for the highly variable flow conditions inside a wind farm, which unpredictably influence the correlations.

scholarly journals A NEW ACTIVE CONTROL STRATEGY FOR WIND-TURBINE BLADES UNDER OFF-DESIGN CONDITIONS

2012 ◽  
Vol 19 ◽  
pp. 283-292 ◽  
Author(s):  
RI-KUI ZHANG ◽  
JIE-ZHI WU ◽  
SHI-YI CHEN
Keyword(s):  
Wind Turbine ◽  
Active Control ◽  
Turbine Blades ◽  
Leading Edge ◽  
Operating Conditions ◽  
Wind Turbine Blades ◽  
Delta Wings ◽  
Control Units ◽  
Shaft Torque ◽  
Active Control Strategy

A new active control strategy for wind-turbine blades under off-design conditions has been investigated in this paper. According to our previous work, in comparison with the traditional straight leading-edge blade, a new kind of bionic blades with a sinusoidal leading edge can significantly enhance the turbine's power output at high speed inflows. However, the wavy leading-edge shape is unfavorable under the design operating conditions since an early boundary-layer separation is inevitable for a wind-turbine blade because of the geometric disturbances of the leading-edge tubercles. But for the present active control, the deflect in wavy leading-edge blades can be eliminated by introducing a series of small flat delta wings as the control units, since delta wings can also generate powerful leading-edge vortices. As a preliminary test, our numerical results show that, the shaft-torque fluctuation in the turbine's stall region can be improved from 27.8% for a straight leading-edge blade (no control) to 8.9% for the present active control; and by adjusting the control parameters, the control units nearly have not any negative effect on the blade's shaft torque under the design conditions. We believe that, as an auxiliary tool of the conventional control strategies, the present active control approach may be favorable to generate a more stable and more controllable power output for wind turbines under all operating conditions (even in the yawed inflows).

Sign in / Sign up

Export Citation Format

Share Document