As onshore wind turbines are installed closer to urbanised areas and in ever-increasing numbers, wind turbine original equipment manufacturers (OEMs) are faced with increasingly stringent noise regulations. To date, this situation has been mostly restricted to the European continent, but other regions in the world are starting to follow this trend very rapidly. Turbine and gearbox manufacturers anticipate this movement and at supplier level, ZF Wind Power has developed an integrated simulation model to cope with these NVH challenges.
Tonality in the wind market
Wind turbine noise can be categorised in several ways, including total Sound Pressure Level (SPL) caused by aeroacoustic sound emissions of wind turbine rotor blades. Tonality can be caused by mechanical noise originating from specific wind turbine components like the generator, gears, cooling fans, bearings, etc. Tonal noise does not drive the total SPL of the wind turbine, but can still be perceived as annoying and therefore needs to be kept within strict limits. A tonality occurs when a tone stands out from the background noise, which, in the case of a wind turbine, is generated by the aeroacoustic emissions of the rotor blades.