Analysis of delay impact on active engine noise control performance

The vehicle active engine noise control (ENC) system enhances driving comfort by generating anti-noise waves to cancel engine noise. Delay is a critical bottleneck affecting practical performance of ENC systems. In this paper, the impact of reference signal delay and secondary path delay on the performance of ENC system based on Filtered-x Least Mean Square (FxLMS) algorithm is thoroughly investigated. A delay module was incorporated into the traditional ENC model. The system’s performance was simulated using an analytical solution, which was subsequently validated through vehicle experiments. This study demonstrates that increases in both reference signal delay and secondary path delay degrade ENC system performance under dynamic acceleration conditions, while having a negligible impact under static steady-state conditions. This research elucidates the mechanism by which delay influences ENC system performance, underscores the critical importance of minimizing delay in system design, and provides a theoretical foundation for developing delay compensation algorithms to enhance system robustness in dynamic scenarios.