As already well-understood/enormous engineering practices, the inverter AC-side
NVH phenomena/mechanisms/measures for motor-equipped vehicle, are already pretty
clear. In addition to inverter AC side–induced NVH issues, DC ripple induced by
PE switching leads to NVH issues manifesting on the capacitor, inductor, and
conductor in terms of reverse piezoelectricity, electrostriction,
magnetostriction, Laplace force, and so forth. These DC-side NVH issues are
already literally analyzed by a couple of literatures, and mechanisms/measures
are explored/applied to electric drive development. And yet, the phenomenon that
a pulsating magnetic field inside a battery pack induced by DC current ripple
off PE switching brings noise at switching frequency inside the vehicle cabin is
newly captured/analyzed by our research, and that has been barely searched
during the literature survey. This newly discovered phenomenon is the pivotal
point in this paper. Although the noise features like the conventional switching
noise that originates at the AC side of the inverter, the mechanism/measures are
different; hence, this newly found NVH phenomenon is termed as alternative
switching noise by the author, distinguishing itself from the conventional
switching noise off AC side of the inverter. The mechanisms and measures
associated with this phenomenon are innovatively explored/analyzed, which
ultimately offer great aid to BEV/HEV/PHEV NVH interpretation/development.
First, in this paper the inverter AC-side NVH issues are overviewed including
mechanisms/measures, then DC-side NVH issues from capacitor, inductor, and
conductor are reviewed in terms of mechanisms/measures, third the extending
exploration/study upon alternative switching noise is described in detail. The
relevant analysis for alternative switching noise is barely mentioned/involved
during literature survey, and that is newly found/studied within the research
delineated in this paper. Fourth, two case studies are exemplified to further
validate the mechanisms/measures employed during investigation. In the end, the
common strategies addressing the alternative switching noise are summarized,
which shall be adopted to keep issues from happening at the very beginning of
vehicle development stage.