| Title |
Performance Improvement of Sensorless PMSM Drives using Motor Friendly Output Filter |
| Authors |
Han-Young Bu ; Seung-Hoon Baek ; Sang-Hoon Han ; Young-Hoon Cho |
| DOI |
10.6113/TKPE.2020.25.4.329 |
| Keywords |
Back-EMF-based estimator; Permanent magnet synchronous motor; Sine-wave output filter |
| Abstract |
A back-electromotive force (back-EMF) estimator for a permanent magnet synchronous motor (PMSM) uses the three-phase voltage references of a current controller to estimate rotor position. However, owing to voltage drops caused by the nonlinear characteristics of switches and passive components, the actual voltage in the motor and the three-phase voltage reference may not match. This study proposes a sensorless control method using a sine-wave output filter applied between the motor drive system and PMSM. The precise voltage in the motor can be measured with the sine-wave output filter and applied to the input of the estimator. Moreover, given that the voltage in the motor can be measured precisely at extremely low speeds, the stable operation range of the back-EMF estimator can be secured. Experimental results show that the proposed sensorless control method has stable operation at extremely low speeds compared with conventional sensorless control. |