Ford Global Technolgoies, LLC

University of Cincinnati

Liqun Na

Ming-te Cheng

Ming-Ran Lee

Mingfeng Li

Takeshi Abe

Teik Lim

Frederick Wayne Vanhaaften

Guohua Sun

Tao Feng

Xuemei Sun

Christopher M Wolf

Jami J Miller

Ramasunder Krishnaswami

A vehicle includes a traction motor having resonance frequency zones, an inverter including switches arranged to drive the traction motor, and a controller. The controller operates the switches only within specified sets of carrier frequencies such that noise side bands corresponding to the carrier frequencies fall outside the resonance frequency zones.

Motor operating region based random pulse width modulation

Method and apparatus are disclosed for active sound desensitization to tonal noise in a vehicle. An example vehicle includes an electric motor, a microphone, speakers, and an active sound desensitizer. The active sound desensitizer (a) randomizes channels of the speakers based on multiple uncorrelated broadband sound profiles, (b) determine upper and lower frequency band limits for a band-limited filter, (c) generate a desensitizing sound based on the upper and lower frequency band limits and the randomized channels, and (d) broadcast the desensitizing sound via the speakers.

Active sound desensitization to tonal noise in a vehicle

An active noise control (ANC) system includes a speaker and one or more processors. The one or more processors implement an adaptive subband filtered reference control algorithm that applies thresholds to reference and error feedback signal paths such that, in response to a series of broadband non-Gaussian impulsive reference signals indicative of road noise in the vehicle having an audible frequency range of 20 Hz to 20 kHz, weight coefficients defining an adaptive filter of the control algorithm converge and permit the ANC system to partially cancel the road noise via output of the speaker.

Subband algorithm with threshold for robust broadband active noise control system

An active noise control (ANC) system includes a speaker and one or more processors programmed to implement a delayless subband filtered-x least mean square control algorithm. The algorithm includes a variable bandwidth discrete Fourier transform filter bank having a number of subbands such that the system, in response to a broadband white noise reference signal indicative of road noise in the vehicle, exhibits a uniform gain spectrum across a frequency range defined by the subbands and partially cancels the road noise via output of the speaker.

Variable bandwidth delayless subband algorithm for broadband active noise control system

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Northville, MI, United States of America

Liqun Na