特种车辆有源噪声控制系统的研究与设计

发布时间：2018-03-13 21:38

本文选题：特种车辆　切入点：有源噪声控制　出处：《浙江大学》2014年硕士论文　论文类型：学位论文

【摘要】：特种车辆内部噪声的危害已经引起相关部门的高度重视,利用技术手段对特种车辆车内噪声进行主动控制,改善车内的人机环境是一项具有重大意义的课题。现有的有源噪声控制系统多停留在仿真阶段,在实际应用中难以达到系统的设计要求。现有的有源噪声控制算法依赖于次级通道模型的建立,需要得到次级通道的精确模型是应用有源噪声控制算法的一个严重障碍。针对以上问题,本文的工作主要从以下几个方面展开：首先,针对适用于仿真实验中的LMS自适应算法在稳定性、降噪效果方面的缺陷,本文对传统的LMS自适应算法加以改进,应用FX-LMS算法建立一个自适应前馈有源噪声控制系统,采用通过估计次级通道过滤后的参考噪声信号来代替直接采集到的参考噪声信号,从而避免因次级通道而产生的延时。并对影响FX-LMS算法性能的因素进行了实验分析,选取最合适的参数可以使系统获得较好的稳定性和降噪效果。其次,鉴于有源噪声控制算法对次级通道模型的依赖,本文在研究现有基于无次级通道建模的有源噪声控制算法的基础上提出了基于同步扰动随机逼近算法的自适应无模型控制方法,克服了因次级通道建模误差引起的不能稳定降噪问题,使有源噪声控制系统的性能得到有效改善。由于有源噪声控制系统中次级声源和误差传声器的布放对降噪效果影响较大,为了能用较少数目的次级声源和误差传声器获得更好的降噪效果和更大的降噪空间,本文以矩形封闭空间为例,通过在LMS Virtual.Lab Acoustics下对封闭空间内有源噪声控制系统进行建模与仿真分析,对次级声源和误差传声器的布放策略进行了研究,得出了有源噪声控制系统中次级声源和误差传声器布放对系统实际降噪效果的影响规律,并在此基础上提出了可行方案。最后,本文还从系统实现的角度来验证了基于无次级通道建模的自适应ANC算法和有源噪声控制系统中次级声源和误差传声器的布放策略。实验证明,本文构建的有源噪声控制系统能有效降低封闭空间内噪声,系统稳定性较好,达到了系统的预定设计目标。
[Abstract]:The harm of interior noise of special vehicles has been paid great attention to by relevant departments. The internal noise of special vehicles is actively controlled by technical means. It is of great significance to improve the man-machine environment in the vehicle. The existing active noise control systems stay in the simulation stage. It is difficult to meet the design requirements of the system in practical application. The existing active noise control algorithms depend on the establishment of the secondary channel model. The need to obtain a precise model of secondary channels is a serious obstacle to the application of active noise control algorithms. In view of the above problems, the work of this paper is mainly carried out from the following aspects:. First of all, aiming at the defects of LMS adaptive algorithm in stability and noise reduction, the traditional LMS adaptive algorithm is improved, and an adaptive feedforward active noise control system is established by using FX-LMS algorithm. By estimating the filtered reference noise signal of the secondary channel instead of the directly collected reference noise signal, the delay caused by the secondary channel is avoided, and the factors affecting the performance of the FX-LMS algorithm are analyzed experimentally. Selecting the most suitable parameters can make the system obtain better stability and noise reduction effect. Secondly, in view of the dependence of the active noise control algorithm on the secondary channel model, In this paper, an adaptive model-free control method based on synchronous perturbation stochastic approximation algorithm is proposed on the basis of studying the existing active noise control algorithms without secondary channel modeling. The problem of unstable noise reduction caused by secondary channel modeling error is overcome, and the performance of active noise control system is improved effectively. Because the arrangement of secondary sound sources and error microphones in active noise control system has great influence on the noise reduction effect, in order to obtain better noise reduction effect and greater noise reduction space with fewer secondary sound sources and error microphones, In this paper, taking rectangular closed space as an example, through modeling and simulation analysis of active noise control system in closed space under LMS Virtual.Lab Acoustics, the placement strategy of secondary sound source and error microphone is studied. The influence of secondary sound source and error microphone placement on the actual noise reduction in active noise control system is obtained, and a feasible scheme is put forward. Finally, from the point of view of system implementation, the adaptive ANC algorithm based on non-secondary channel modeling and the placement strategy of secondary sound source and error microphone in active noise control system are verified. The active noise control system constructed in this paper can effectively reduce the noise in the closed space and the stability of the system is good.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB535

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