A novel motor speed calculation method using square wave speed sensor signals via fast Fourier transform

摘要

This paper presents a novel motor speed measurement methodand experimental results using the fast Fourier transform (FFT).Motor speed is obtained using the square wave output signal of a speedsensor. In the proposed method, the speed can be measured in a widerange, and transient speed changes can also be clearly observed. Theexperiments were conducted during start-up and in steady state. Thesampled speed data were transformed to frequency spectrums using theFFT. The frequency, which corresponds to the maximum amplitude in thespectrum, was used to calculate the motor speed. The test resultsshow that the proposed method is very useful.