柴油机排气噪声有源消声系统的设计与实现

为解决柴油机排气低频噪声问题,基于噪声有源消声技术理论,选用与排气噪声相关的转速信号作为数字信号处理控制器的参考信号,以自适应陷波滤波算法为基础,采用次级通路离线自适应建模方式,设计了单通道有源噪声前馈控制系统,并在Matlab平台上进行仿真分析,最终选取迭代步长μ为0.003。在某柴油机排气管路上进行了排气噪声有源消声试验,120 Hz时降噪量达到了13 dB(A);系统收敛速度快且具有良好的稳定性。

Design and Realization of Active Control System for Diesel Engine Exhaust Noise

In order to solve the problem of diesel engine exhaust low-frequency noise, the theoretical basis of active noise control (ANC) technology was introduced. The speed signal related to the exhaust noise was selected as the reference signal for the digital signal process (DSP) controller. Based on the adaptive notch filtering algorithm, the single-channel active noise feed-forward control system was designed by using the secondary path offline adaptive modeling method. Simulation analysis was carried out on the Matlab platform, and the iteration step of 0.003 was selected finally. An active noise control test for exhaust noise was carried out on the exhaust pipe of a diesel engine. The noise reduction reaches 13 dB(A) at 120 Hz, and the system has fast convergence speed and good stability.