The mechanical components of a wind turbine generate noises. These can be perceived as disturbing. At the same time, they can be an indication of component wear. The X-Energy sub-project X-Eptance Impulse has set itself the goal to increase the sustainability and acceptance of wind turbines. To this end, a low-cost, synchronised, multi-channel measurement system for acoustic signals was developed using state-of-the-art, highly integrated components. This is used for the permanent measurement of noise emissions from wind turbines and their minimisation by the turbine control system. In addition, a noise database was developed for early acoustic fault detection.
Results
To begin with, measurements were carried out at the Curslack wind farm using a commercially available acoustic camera. The data obtained formed the basis for the noise database that is currently being developed and provided initial indicators for individual noise patterns. The next step was to carry out measurements with the company's own prototype and compare the results with the existing acoustic camera.
The prototype consists of 12 individual SmartAcousticSensors (SAS), which were combined to form a measuring unit. A data point of a measurement can be composed of a microphone for audible sound, a microphone for ultrasound and an acceleration sensor for recording vibrations. In addition to the hardware development, also the firmware for the hardware components contained in the system was developed. Function and performance tests were carried out in a free-field room and a reverberation room. Following the successful explorations of the acoustic behaviour in the laboratory, the system was installed on a wind turbine in the wind farm and put into operation.
Moreover, a prototype integration of the status detection and the development of a prototype turbine control system based on data measured with the developed array were carried out. Besides, a prototype of an auralisation at the Bergedorf campus was implemented as a model of a wind turbine in a green environment with forest and can be reproduced in the CAVE of the Sim-Lab.
