A Speed Measurement Method Using AUV Radiated Noise Spectrum

An inverter-fed motor radiate noise rich in spectral lines. The spectral lines located symmetrically around the multiples of the switching frequency of inverter. The sailing speed of an AUV powered by inverter-fed motor can be measured using the spectral line pairs' symmetry characteristics with Doppler effect. First of all, the article describes the spectral line features of the inverter-fed motor. Secondly the equation for calculating speed is derived. Finally the method to calculate sailing speed of AUV is proved feasible by simulation and experiment.