PSW simulates, develops and optimises NVH properties (noise, vibration, harshness) in accordance with class 1 semi half-space domains with a lower frequency limit of 100Hz as certified by ISO-3735. Similar work is also carried out on the aeroacoustics in thermal and interior climate control systems.
The commissioning of a new acoustic test chamber at the Gaimersheim site is a key example of how PSW is strategically investing in the electric future of driving. Here, typical engine noises are eliminated and yet at the same time, electric vehicle components are added that generate sound noticeable to the driver.
In the case of electric vehicles, customers find noises arising from ancillary units, such as the heat pump, unpleasant. The air conditioning and noises caused by its air outflow are also much more dominant and annoying than in cars with internal combustion engines. “In the premium segment, every component has to meet customers’ high demands in all operating conditions,” explains Ignacio Martin Garcia, acoustics expert at PSW.
Completely new load cases such as HPC charging (high power charging) are also being developed and validated.
In this case, the battery must be cooled considerably while the vehicle is stationary, as HPC charging produces more waste heat than during a typical cross-country journey. This is due to the battery being charged faster than the rate it discharges during normal driving. Since there is no wind resistance to cool the battery, the fan has to work much harder. Especially in the case of vehicle charging parks near residential areas, fan cooling noises could lead to complaints from residents. “High demands here mean developing a premium and pleasant charging noise that exceeds the normal legal requirements,” explains Dr. Andreas Businger, head of the aerodynamics/flow acoustics development department.
