Pass-by Noise Generating System in Battery Electric Vehicle

Battery Electric Vehicles (BEVs) are gaining momentum all around the world and India is not far behind in terms of EV sales. The principle difference between BEVs and Internal Combustion Engine based Vehicles (hereafter known as ICEs) is that BEVs run on electric motors and don’t have Internal Combustion based engines that generate significant noise while running. The engine noise contributes to noise pollution, but it is useful in alerting the pedestrians about the incoming vehicle and can function as a passive safety system. The lack of such noise can be a safety threat to pedestrians, cyclists, wildlife etc. Many countries around the world have mandated, or are in the process of mandating, a pass-by noise generating system to alert pedestrians about the incoming vehicle. This paper is an attempt to study various pass-by noise generating systems used worldwide in electric four-wheelers. A majority of those systems use speakers located on the exterior of the cabin to mimic noise generated by IC engines. This paper describes a detailed comparison of the pseudo-sound generating devices, enlists advantages and disadvantages of each system and also suggests a proposed pass-by noise generation system (PSGS) considering Indian road conditions. In the future, this paper can be used as a reference for the development of pass-by noise generating systems.