A Novel Design of Low Pass Filter in Disturbance Observer for Speed Tracking of Permanent Magnet Synchronous Motors

This work proposes an approach to find an appropriate bandwidth of a first-order low pass filter (LPF) used in a DOBC. It is established that an observer in the DOBC can guarantee precise estimation if its bandwidth is set as high as possible in order to reject disturbances in a broad frequency range. On the other hand, there is an upper bandwidth limitation due to the system robustness and potential noises; hence, the bandwidth is required to set to be smaller than the limit. In this work, we propose a method of selecting proper bandwidth for the LPF in the DOBC. To show the effectiveness of the proposed method the experimental studies are carried out using the permanent magnet synchronous motor (PMSM)..