Title |
Sensorless Control of a Surface Mounted PM Synchronous Motor in Over Modulation Regions by Detecting Phase Voltages |
Authors |
Hae-Jun Choi ; Han-Sol Lee ; Kwan-Yuhl Cho ; Hag-Wone Kim |
DOI |
https://doi.org/10.6113/TKPE/2018.22.1.53 |
Keywords |
Sensorless ; Three phase voltage ; Overmodulation ; PM synchronous motor |
Abstract |
The information on the actual voltages and actual currents of the motor is required for the sensorless control of a permanent magnet synchronous motor without rotor position sensors. In the model-based rotor position estimator of a PM synchronous motor, the reference voltages, which are the outputs of the current controller, are commonly used. The reference voltages in over-modulation regions for high-speed operation differ from the actual voltages applied to the motor. Consequently, the estimated rotor position and rotor speed may fail to track the real rotor position and real rotor speed. In this paper, the sensorless control for a PM synchronous motor in over-modulation regions for high-speed operation is proposed. The three-phase voltages applied to the motor are measured by using additional voltage detection circuits, and the performance of the rotor position estimator based on the measured three-phase voltages is validated through the experimental results. |