Research On Active Noise Control Based On Optimization Algorithm And Its Application

With the development of the society, people’s requirements for better life increase day by day. One of the requirements is to be free from the noisy environment. Compared with the traditional noise control method, active noise control has its advantage to attenuate low-frequency noise, which makes it more and more important in the noise reduction domain. So, this dissertation choose to do a research on the improvement of the active noise control and its application.Firstly, the basic structures and principles are analyzed by introducing the feedback, feedforward, hybrid active noise control system respectively. Then on this basis, traditional active noise control algorithm is derived, which includes the Filtered-X LMS algorithm, the offline secondary-path estimation algorithm and the online secondary-path algorithm. Furthermore, the theoretical analysis about the active noise control based on traditional algorithm’s drawback, where the secondary-path estimation have to be done in advance, is given and at the same time, the Matlab simulation results is obtained to verify this theoretical analysis, which gives the meaningful reason to the improvement based on optimization algorithm for active noise control.Secondly, a bacterial foraging optimization algorithm is selected as the optimization algorithm discussed in this dissertation. Then, the principles, implementation process and the main parameters’ choice of this algorithm are introduced at length. From this basis, some improvements of the bacterial optimization algorithm are given for making it suitable for active noise control; after finding the joint of optimization algorithm and active noise control, the active noise control based on optimization algorithm is given.Subsequently, Matlab application simulations about this improved active noise control have been done, whose application object is the noise generated by washing machine which is on its dewatering process. Simulation results show that the drawback of active noise systems based on traditional control algorithm is overcomed by this improved active noise control system. Then some relative simulations have been done to show how the results are influenced by the different choices of main parameters.At last, the hardware design of this active noise control based on optimization algorithm is discussed briefly.