Optimizing NVH for EVs

Unique acoustic and harmonic challenges require an integrated approach to simulation and analysis. An expert at Adaptive Corp. explains.

Despite global sales market share stuck at single-digit levels, electric vehicles (EVs) are steadily filling the development pipelines at major OEMs. And as engineers are acutely aware, EVs bring a paradigm shift in the noise, vibration and harshness (NVH) arena. Their harmonic spectra are dramatically different than those of even the smoothest, most refined combustion-engine vehicles and hybrids.

EVs are anything but silent, however. They've got their own acoustic challenges, experts assert. Traction motors can be relatively quiet (in terms of tonal harmonic noise) in the low and mid frequencies, but unmasked gear whine and various sounds in the propulsion system are far more noticeable and potentially annoying. There's also the relative cacophony of tire noise, HVAC fans and compressor cycling. Even electrical switching and the muffled gurgle of battery coolant can be heard in some EVs while at rest.