Molas NL - Nacelle Wind LiDAR for Wind Turbine Power Performance Test

Comparing to the nacelle wind LiDAR solution for wind turbine power performance test, the traditional methodology with Met-mast needs to install a wind measurement tower in the main wind direction of the wind turbine under test, and set up a barometer, a hygrometer, a thermometer and other equipment, and the cost is high, the test time is long and the project is also more complex.

Additonally, there is still a certain distance between the wind measurement tower and the wind turbine, which will lead to certain deviations in the wind measurement data. If nacelle mounted wind LiDAR is used instead, it can measure wind speed and wind direction at the same location with the wind turbine rotor, which can effectively increase the area of the test sector, shorten the test time, reduce costs, and make the data analysis results more accurate.

Molas NL is a nacelle wind lidar which is independently developed by Nanjing Movelaser for wind power customers’ intelligent application solutions. It is a remote sensing laser device which can be installed above the wind turbine nacelle. It uses a coherent detection system based on the principle of laser Doppler frequency shift to achieve an accurate measurement of the wind vector field from the top of the nacelle to the front tens of to several hundred meters ahead of turbine rotor.

Molas NL measures and records wind data information of 400 m in front of wind turbines. After it’s connected to the main control system of the wind turbine, it can realize the functions in a variety of automated operating scenarios such as yaw control, load optimization, power curve test and so on.

In June 2019, Movelaser Molas NL nacelle-based wind lidar was installed at an offshore wind farm in Zhoushan, Zhejiang Province.It was applied to the power curve verification of offshore wind turbines.The wind turbine is Siemens 4.0MW model with a hub height of 90 meters and a blade length of 62.5 meters.The cost of setting up a offshore Met-mast is millions of RMB, which is difficult to construct, expensive and unable to move. Movelaser Molas NL nacelle-based wind lidar can adapt to the marine environment very well, the equipment cost is low, installation and dismantling only takes half a day, saving a lot of time and costs. It is currently the best choice for offshore wind measurement for power curve validation.

structural load can be reduced

0 %

turbine AEP can be increased

0 %

Units have been deployed on wind turbines

Simultaneous measurement ranges

Measurement Parameters

Measuring distance	50-400m
Measure the number of Ranges	10
Sampling frequency	4Hz
Wind speed measurement accuracy	0.1m/s
Wind direction measurement accuracy	0.5°
Wind speed measurement range	0~50m/s
Wind direction measurement range	-90°~90°

General Parameters

Power Supply	240V
Weight	<35kg(Optical head) <25kg(Digital storage unit)
Range of working temperature	-40℃ ~ 60℃
Survival temperature range	-40℃ ~ 65℃（Power off） -45℃ ~ 65℃（Power on）
Working humidity range	0% to 100%
Protection level	IP65(In-flight equipment) IP66(Off-board equipment)
Anti-corrosion grade	ISO C5
Eye safety	IEC / EN 60825-1 ANIS Z136-1
Communication method	customizable

Download the Full specification of Molas NL.

Certification and Calibration Reports of Molas NL Nacelle Wind LiDAR

DNV-GL Load Reduction Certificate

Molas NL working together with EFARM algorithm has been certified by DNV-GL that the loads on tower, blades were significantly reduced comparing to the baseline.