Noise Control Method of Hybrid Engine Based on Masking Effect

The mismatch between the engine noise and the vehicle speed of hybrid vehicles in the state of battery depletion constitutes one of the main noise sources of the vehicles. A noise testing method for the hybrid engine was proposed with the aid of the rotating hub test bench. The data of the in‐vehicle engine noise under various operating powers were parsed, and simultaneously, the background noise data within the vehicle during the uniform‐speed driving in the pure electric driving mode of the vehicle were collected. Based on the acoustic masking effect, a subjective evaluation method has been developed to assess the masking impact of background noise on engine noise within vehicles. Analysis of the subjective evaluation results revealed that a fundamental condition for effective masking of engine noise by background noise is that the latter must sufficiently envelop the characteristic spectrum of the engine noise. Ultimately, the vehicle calibration strategy was refined based on the outcomes of subjective evaluations. This adjustment not only enhanced the vehicle’s NVH performance but also introduced an innovative approach to engine noise control in hybrid vehicles operating in series mode.