Study On The Adaptive Active Noise Control System For The Cab Of Locomotive

ABSTRACT:Noise is an increasing concern as one of the most common pollutions in our days. Locomotive cab is the main place where the engineers work in. And the condition of the cab's noise is related to safe running of railway and the healthy of the engineers. So study and control the noise of locomotive cab is very necessary.The main peak of interior noise is around middle and low frequency in the locomotive cab. Because the results of the active noise control is better than tradition noise control for controlling low frequency noise, study and control the noise of locomotive cab is based on the active noise control system.First, the character of the noise in the cab is been analyzed. The feed forward adaptive active noise system is been designed for the cab. The system which is based on FXLMS algorithm is been implemented with Simulink tool. The conclusion coming from the results of the simulation system is that the steady state error is correlative with coefficient of convergence.Secondly, a single channel feed forward adaptive active noise control system based on LabVIEW platform and notebook PC is achieved. Adaptive filter is designed based on mixed program between LabVIEW and MATLAB. The sample sounds subsystem, the play sounds subsystem and the secondary path adaptive modeling subsystem all adopt virtual instrument which is consisted of LabVIEW and the notebook PC hardware. The single-frequency sine wave noise which adds the random noise has been cancelled well by the system. Study on the system performance by the results of system operation, and get the best scheme for the position of secondary sound source.Last, experimental results show that the steady state error and velocity of convergence are correlative with the noise frequency. Noise frequency mixing and the steady state error are interrelated.