The rapid increase in the number of wind farms has created serious concerns about wind turbine interference on surveillance, navigation, and Doppler weather radars. This concern has resulted, in particular, in halts or delays in a number of proposed installations in Europe and the US.
Physikalisch-Technische Bundesanstalt (PTB): Wind farms and radar
The measuring system consists of a reference antenna and a receiving facility. In the design used to date, it hangs down from a helicopter and can measure the electromagnetic field strength at any random location in space and synchronously save the measured data as well as the exact position with a very high sampling rate. Successful tests have already demonstrated that this system measures the electromagnetic far field which is necessary for a flawless signal transmission (e.g. between an instrument landing system and an aircraft) as precisely as required by the International Civil Aviation Organization (ICAO). These validation measurements are traceable to the International System of Units (SI), which ensures its comparability.
As the latest development, the measuring system was miniaturized and mounted onto an octocopter of approx. 80 cm in width. On such aerial vehicles, the system can be used at places where wind farms already exist or where they are planned in order to acquire data with regard to the field strength and to modified signal contents at any selected coordinates over longer periods.
Wind Turbine Radar Modeling and Analysis.pptx - wind_turbine_radar_modeling_and_analysis.pdf
Air Force looks to solve wind farm radar interference -- Defense Systems
AGI’s simulator, known as ROEMS, works with the company’s Systems Tool Kit modeling program, which has been used by NASA, the Marine Corps and the Air Force on projects ranging from network architecture analysis to airborne early warning, according to the company. The new simulator, to be called ROEMS II, will be a “straight-forward configuration control architecture” to help radar system designers account for wind turbine interference, the Air Force’s announcement said.
Radar interference from wind turbines isn’t a new problem, but it’s becoming more common as wind farms proliferate. Any structure, such as a building or TV tower, can reflect radar. Wind turbines can complicate things depending on their height, size of blades and the speed of their rotation. The amount of interference can range from none at all to significant, and could depend on the sensitivity of the radar equipment.
AGI Blog
AGI awarded IEEE Philadelphia Section Corporate Technology Innovation Award for software that analyzes the effects of wind farms on radar systems
Wind Turbine Radar Interference Reduction Patents
A lot of research and patent activity in both reducing RCS of wind turbines and mitigating interference in doppler radar is being done. The following patents resulted from a Google search "radar wind turbine interference":Reducing radar interference from wind turbines
www.google.com/patents/US20130017096App. - Filed Jul 13, 2011 - Published Jan 17, 2013 - Charles Holley - Charles HolleyA wind turbine including components formed from or coated in a radar absorptive material. A method for scanning an area having one wind ...Method for mitigating the effects of clutter and ...
www.google.com/patents/US20110260908App. - Filed Dec 8, 2009 - Published Oct 27, 2011 - Christopher New - Qinetiq LimitedThe interference primarily occurs over the region of the wind farm, but due to some types of radar processing, the problem can extend over a ...Wind turbines
www.google.com/patents/US20130135135App. - Filed Apr 27, 2011 - Published May 30, 2013 - Steve Appleton - Vestas Wind Systems A/SThe present invention relates to the use of radar-absorbing materials in connection with wind turbines for reducing interference caused by wind ...Wind turbine with reduced radar signature
www.google.com/patents/US20100166547App. - Filed Oct 6, 2009 - Published Jul 1, 2010 - Walter M. Presz, Jr. - Flodesign Wind Turbine CorporationIn addition, the wind turbine may cause direct interference by virtue of high reflectivity reducing the radar sensitivity and may produce false ...Improvements relating to wind turbines
www.google.com/patents/WO2011138597A2?cl=enApp. - Filed Apr 27, 2011 - Published Nov 10, 2011 - Steve Appleton - Vestas Wind Systems A/STechnical field The present invention relates to the use of radar-absorbing materials in connection with wind turbines for reducing interference ...Wind turbine providing reduced radar signature.
www.google.com/patents/EP2400152A2?cl=enApp. - Filed Jun 8, 2011 - Published Dec 28, 2011 - Francis Eugene Parsche - Harris CorporationIndeed, a wind turbine assembly may cause both reflectivity and motion interference that may impact any radar site that covers the region ...Wind turbine with reduced radar signature
www.google.com/patents/EP2412525A1?cl=enApp. - Filed Jul 29, 2011 - Published Feb 1, 2012 - Walter M. Presz Jr. - Flodesign Wind Turbine Corp.In addition, the wind turbine may cause direct interference by virtue of high reflectivity reducing the radar sensitivity and may produce false ...Wind turbine with reduced radar signature
www.google.com/patents/US20110020110App. - Filed Jul 29, 2010 - Published Jan 27, 2011 - Walter M. Presz, Jr. - Flodesign Wind Turbine CorporationIn addition, the wind turbine may cause direct interference by virtue of high reflectivity reducing the radar sensitivity and may produce false ...Wind turbine with reduced radar signature
www.google.com/patents/EP2334930A1?cl=enApp. - Filed Oct 6, 2009 - Published Jun 22, 2011 - Walter M. Presz, Jr. - Flodesign Wind Turbine Corporation[0004] In addition, the wind turbine may cause direct interference by virtue of high reflectivity reducing the radar sensitivity and may produce ...Wind turbine with reduced radar signature
www.google.com/patents/CA2747473A1?cl=enApp. - Filed Jul 28, 2011 - Published Jan 29, 2012 - Walter M. Presz, Jr. - Flodesign Wind Turbine Corp.In addition, the wind turbine may cause direct interference by virtue of high reflectivity reducing the radar sensitivity and may produce false ...
WxAnalyst Ltd has been able to document wind farm occultation for years. We have occultation algorithms that easily show the problems, and our software can be used in site selection should the installer consider this problem.
ReplyDeleteMy patent, application # 13/803,264 Radar Wind Turbine, filed March 14,2013 directly solves this problem.
ReplyDeleteIts basically an airborne SAR/ISR in a radome on the wingtip of the wind turbine. To my knowledge its not been built but the patent is fully filed (should be published on USPTO.gov within 5 months from today) (build it first and pay typical royalties to LM (assignee/sponsor)). Its claims mix the benefit of the wind turbine with that of Radar being a power centric and LOS limited device. Fantastic elevation (LOS), circular motion (enables SAR/ISR and Doppler), Local power generation w/o conversion/transmission losses (power centric), can grid-power it to actively steer it for 3D imaging and keep imaging in low wind, can have multiple radars (1 per wing-tip radome) at differing frequencies.