Challenges in NVH refinement of electric vehicle built on ICE platform

In recent years electric vehicles have seen rapid sales growth globally. Also, there is a massive push from global institutions for transition to electric mobility in the interest of reducing greenhouse gases and adhering to climate change agreements. In India, union government has set the target of 30% EV penetration in private cars, 70% in commercial vehicles & 80% in 2 wheelers by 2030. To meet such ambitious targets in a developing country like India, low-cost solutions are needed to democratize the electric mobility. In the case of electric cars, conversion of ICE platform to electric is the most cost feasible solution but at the same time it comes with various challenges. An electric car is being developed carrying over the top hat from the ICE version. Underbody is being redesigned to accommodate battery module under the floor. Except for BEV architecture, most of the parts are carried over from ICE platform to reduce development time and leverage cost advantage. NVH challenges faced related to Electric drive machine whining noise, auxiliary drive noises like e-Vacuum pump, e-Compressor etc. are explained in detail along with counter measures taken. Due to carryover of ICE platform to BEV challenges faced with road noise performance, cooling system noise etc. are also discussed in the paper. 3 Step process followed to resolve the issues which includes. 1. Source level refinement 2. Software logic optimization 3. Passive treatment to reduce intensity of the issue With the above strategy adopted NVH performance is fine tuned to meet program requirements. Considerable improvement in NVH performance observed between baseline vehicle and fine-tuned vehicle.