Sound emission measurements and measurements for acceptance tests acording to IEC 61400-11 and FGW guideline, systems for the reduction of gearbox tonalities and for sound source localization with the acoustic camera

Wind turbines generate sound and thus emit acoustic noise. In the course of the turnaround in energy policy, new locations for wind turbines have to be found and there is a huge potential for conflict due to noise pollution.

We offer services and product solutions covering the entire wind turbine approval procedure, from noise impact prediction in the planning phase to acceptance measurement following the commissioning of a wind turbine.


Please contact me personally

________

I will be happy to advise you on questions regarding our system and service offerings in the areas of sound and noise.

Dipl.-Ing. Janosch Blaul

+49 931 49708-235
blaul@woelfel.de
Formular

Sound emission measurements and measurements for acceptance tests according to IEC 61400-11

  • As part of the approval of your wind park under immission control law, you want to verify the compliance with sound power levels and document their correct determination?
  • The newly developed prototype of your wind turbine requires the measurement of acoustic emissions as a basis for the type certification?

As a member of the Fördergesellschaft Windenergie (FGW e.V.) (Society for the Promotion of Wind Energy) we perform measurements of emitted acoustic noise and measurements for acceptance tests according to IEC 61400-11 and FGW guidelines. Sound immission control particularly deals with questions of noise propagation outdoors. The objective is to ensure compliance with limit values (Technical Instructions on Noise Abatement) in order to protect the people in the vicinity.

The central success factor for sound emission measurements is a fast reaction time under favorable wind and weather conditions. With branches in Höchberg near Würzburg, Hamburg and Berlin, we can carry out measurements flexibly and efficiently in both southern and northern Germany.

The efficiency of our measurements has also significantly increased with our wireless measuring system RoBin (link to Tab): The time from our arrival at the wind turbine to the start of the measurement is only about 30 minutes due to the simple setup. For example, several wind turbines and several operating modes can be measured in accordance with standards on one measuring day.

Sound Source Localization with the Acoustic Camera Noise Inspector

  • You want to know exactly which parts of the wind turbine increase the noise level or cause tonalities? You also want to know how these tonalities can be eliminated?

In order to be able to plan and initiate noise abatement measures, it is necessary to know the exact source of the noise. We have various measuring systems to cover almost all cases. The acoustic camera Noise Inspector locates sound sources and displays the results as an acoustic photo or video.

We support you when you are confronted with acoustic issues – whether you just have to locate a sound source or want to develop noise abatement measures.

Our references in the area of sound source location (extract):

  • Rhein Energie AG
  • GE Wind Energy GmbH
  • Enercon
  • Vensys Energy AG
  • MAC Energysystems GmbH & Co. KG

Please contact us personally

________

We would be pleased to support you in solving your problem concerning "Wind turbine vibrations" and advise you on questions regarding our system and service offerings in the areas of structural health monitoring, vibration reduction, sound and noise as well as structural design.

Dr.-Ing. Georg Enß

+49 40 524715-262
enss@woelfel.de
Formular

Timo Klaas

+49 40 524715265
klaas@woelfel.de
Formular

Dipl.-Ing. Bernd Wölfel

RoBin – System for the measurement of sound emissions of wind turbines according to IEC 61400-11 Edition 3 / FGW Guideline TR1

RoBin is our wireless measuring system for the standard-compliant sound emission measurement at wind turbines. From the time of arrival at the wind turbine to starting measurements is only about 60 minutes due to the simple setup. The recorded data are compiled in real time and evaluated according to the standard. The results are thus available directly on site. This makes it possible to respond individually to the wind situation and to conduct measurements for several wind turbines and in different operating modes on a single day in accordance with the standards.

The advantages of RoBin at a glance:

Practical: Wireless data transmission

 

Economical: Time saving through real-time evaluation

 

Compact: Practical transport case

 

Flexible: Various interfaces for data acquisition

 

Precise: Calibratable sound level meter

 

Convenient: Remote control for marking noise

 

The main component is a sound level meter for detecting noise via a double-shielded external microphone. A flexibly applicable data logger with six freely configurable analog interfaces, a USB and a fieldbus connection registers the operating parameters of the wind turbine. Weather data is recorded with meteorological sensors with the required class of accuracy.

Data transfer and power supply are provided via WiFi and lithium battery technology. A radio remote control is used to mark the status of the measurement (operating or background noise) and to identify interfering noises. The wind bins are managed automatically in real time. The course of the measurement can be conveniently monitored remotely via tablet.

The evaluation of the data necessary for the sound power determination is done with our sound analysis software RoBin.Post, which is tailor-made for wind energy. Here, both the data recorded directly with RoBin and measurement data recorded elsewhere can be processed. The data evaluation according to IEC 61400-11 and FGW TR1 (Edition 2.1 and 3) works at the push of a button. The automatic report output – directly after the measurement – makes the process particularly efficient.


Please contact me personally

________

I would be pleased to advise you on questions regarding sound emission measurement at wind turbines and our measuring system RoBin.

Dieter Müller
RoBin

+49 931 49708512
mueller@woelfel.de
Formular

Reduction of gearbox tonalities with active or passive damping devices

Vibrations in the gearbox of a wind turbine can cause tonalities (noise with a fixed frequency, e.g. whistling noise). These tonalities are particularly unpleasant for people and thus they have to be specifically considered in the evaluation of noise emissions. In accordance with legal standards, surcharges are therefore assigned to the determined sound power level of the wind turbine. With this surcharge, the authorized limits for noise emissions or the contractually agreed noise levels may be exceeded.

Therefore, tonalities have to be reduced. In the wind energy sector, Wölfel has many years of experience in the application of active and passive absorbers, which compensate the vibrations at their source before they can spread. This is achieved with precisely applied counter-vibrations.

By moving the black dots you can calculate your individual payback period with our interactive tool:

 

Amortisation after

12months

not possible

Noise-reduced operation of your WTG can massively reduce the yield of your wind farm. With ADD.Soundyou minimize tonality and can return to the normal operation mode. This calculation includes all costs including installation.

 

With more than 800 systems in the market, we are proud to be the technology leader in the field of active damping devices for the reduction of gearbox tonalities.

  • ADD.Sound compensates several orders of tonal gearbox vibrations at variable speed (over the entire speed range of the wind turbine)
  • One ADD.Sound active absorber each is mounted on the torque supports (can also be retrofitted; small installation space required)
  • A compact control cabinet is installed in the nacelle
  • Due to the speed-adaptive control algorithm, ADD.Sound generates active forces which eliminate the tonal excitation forces in the gearbox
  • Tonal sound is cancelled over the entire range of speed (broadband effect, simultaneous compensation of several tonalities)
  • Compensation of one order of tonal gearbox vibrations at one fixed speed (mostly the rated speed of the wind turbine)
  • One passive absorber TMD.Sound each is mounted on the torque supports (can also be retrofitted)
  • TMD.Sound is exactly adjusted to the tonality frequency at rated speed
  • TMD.Sound applies a force that is exactly opposite to the excitation
  • Tonal sound at rated speed is cancelled – no energy supply is required

Please contact us personally

________

We would be pleased to support you in solving your problem concerning "Wind turbine vibrations" and advise you on questions regarding our system and service offerings in the areas of structural health monitoring, vibration reduction, sound and noise as well as structural design.

Dr.-Ing. Georg Enß

+49 40 524715-262
enss@woelfel.de
Formular

Timo Klaas

+49 40 524715265
klaas@woelfel.de
Formular

Dipl.-Ing. Bernd Wölfel