Abstract
This paper is concerned with a practical controller to suppress the periodic speed variation of a motor. Speed variation in a pump, a compressor or a wheel of an electric vehicle causes vibration and noise, which shorten the life of the machine. Although repetitive control can suppress the speed variation, there are the following problems:
If a reference velocity changes, the period of the speed variation changes and the effect of the suppression is reduced. The tuning parameters are difficult to tune.
In the case where a low-resolution angle sensor is used, the output of the controller to suppress the speed variation becomes pulse-shaped and causes harmonic ripples that increase energy consumption. In order to eliminate the harmonic ripples, we propose a controller of which the output is interpolated with a sine wave.