Unique methodology combining IEC standard compliance with in-depth analysis
- Introduction to wind turbine certification testing
- Beyond the IEC 61400-11 Standard
- A full portfolio of solutions for the wind industry
- Reliability
- Dynamics
- Noise emission
- Testing & Correlation
- System optimization
1. Introduction to wind turbine certification testing
With the LMS IEC 61400-11 solution [1], wind turbine manufacturers can check the emitted noise levels of their turbines before going into formal certification. While guaranteeing compliance to the IEC 61400-11 standard, the proposed solution [3] offers much more flexibility for in-depth insight into the phenomena contributing to the overall noise level. Real-time feedback on octave and narrow-band frequency content as well as detailed tonality analysis allows pinpointing and isolating those components contributing most. Through the availability of this feedback while the measurements are running, on the spot last-minute modifications to the turbine (components) become possible. Using a unique and smart way of combining measurements for different wind bins drastically reduces the time for the total measurement campaign: from weeks to possibly under a day.
The presented solutions respond to a call for increased efficiency from the manufacturers, consultants and certification agencies by delivering a flexible system and realizing a productivity increase of the measurement campaigns.
2. Beyond the IEC 61400-11 Standard
The LMS solution is more than an IEC-compliant solution. In addition, it increases the engineering insight and offers the ideal environment to pinpoint the root causes and do last-minute modifications to the wind turbine before releasing it for the final certification step.
As an illustration, please find below some specifications that go beyond what the IEC standard requires:
- 4 microphone positions instead of 1
- 1 downwind position as required by IEC
- 3 optional (e.g. 2 at +-60° of downwind and 1 at upwind position)
- Wind speed from anemometer or power curve from the turbine
- Selectable data segments (< 1min) for faster analysis
- Alarm when outside +- 15 degrees of the wind direction
- Real-time analysis, no “blind” recording, no post processing
- clear overview of all status channels
- octave and narrow-band spectra
- tonality spectra
- Zoom, replay and filtering of microphone signals
- Integrated reporting with MS Office
The same system can be used for advanced engineering as illustrated below and for other standards like IEC 61400-13 [2] where measurement of strain gauges is required.
3. A full portfolio of solutions for the wind industry
A. Realiability - Surviving 20 years of wind loads
- IEC 61400-13 compliance
- Analyze hundreds of wind scenarios in one click
- Reduce maintenance costs by design optimization
- Identify hotspots and visualize damage distribution
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B. Dynamics - Real-life simulation, accurate testing
Testing and modeling of:
- full wind turbine
- driveline & gearbox
- blades, tower,...
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C. Noise emission - comply with stringent regulation
- IEC 61400-11 compliance
- Acoustic measurement
- Acoustic troubleshooting
- Acoustic simulation:
- Simulate tonal noise
- Simulate blade aerodynamic noise
- Predict the noise before the wind turbine is built
- Optimize the design for lower noise emission
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D. Testing & Correlation - Improve model accuracy
- Impact hammer and shaker testing
- Operational modal analysis
- Improve simulation models via test correlation
- Test based realistic loads
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E. System optimization
Optimize hydraulic, thermal, electrical & mechanical performance
- Gearbox, transmission and braking systems design
- Blade pitch and yaw control systems design
- Power drive sizing (generator, inverters and controls)
- Thermal management of the nacelle
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Conclusions
LMS has worked extensively with wind turbine manufacturers and suppliers and offers a full portfolio of simulation tools, testing systems and services. The following results have been reported by customers using the LMS tools:
- Extremely productive IEC 61400-11 measurement campaigns: from weeks to under a day
- Solution for both IEC 61400-11 (noise emission) and IEC 61400-13 (measurement of mechanical loads) in one system
- Engineering insight in noise, vibration and durability issues based on integrated test and simulation tools
