The main advantages of electric LDT's, (Light-duty Trucks), namely: lower running and maintenance costs, zero-emissions and eco-friendly image heavily outweigh their disadvantages, specifically their higher charging time compared to ICE (internal combustion engine) vehicle refuelling and their shorter range. These advantages make electric LDTs viable because they are compatible with the driving cycles of fleet customers.
Noise generated by electric LDTs is expected to be low compared to ICEs; however, the interior and exterior noise has high-frequency noise components that are usually subjectively perceived as unpleasant or annoying. The tonal components present in electric vehicles are judged as unpleasant by the vehicle's occupants, and other noise components that are usually masked by the ICE are clearly perceived, as the overall noise is lower.
A complete interior and exterior noise analysis using different motor loads and conditions was carried out in order to verify fulfilment of the initial objective and subjective target requirements. The calibration of the inverter was analyzed and modified in order to improve the interior noise of the vehicle and the exterior noise perceived from outside the vehicle, which were perceived as annoying by the participants in the jury test due to the presence of some high-frequency tonal components.
This paper describes the procedure followed for reducing the NVH, the results obtained during this process, and the conclusions obtained from the study.