| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a stable torque output without torque ripple by performing current feedback control, when one of the current detectors of different phases of a three-phase AC motor becomes defective to allow noises to be mixed therein. <P>SOLUTION: A current controller for a three-phase AC motor comprises a first rotary coordinate converter for converting current to a first d-axis current and a first q-axis current based on the information of the current detectors of the U-phase, the V-phase, and the W-phase of the three-phase AC motor; a second rotary coordinate converter for converting current to a second d-axis current and a second q-axis current, based on the information of the detectors of the U-phase and the V-phase; a third rotary coordinate converter for converting current to a third d-axis current and a third q-axis current, based on the information of the detectors of the U-phase and the W-phase; and a fourth rotary coordinate converter for converting current to a fourth d-axis current and a fourth q-axis current, based on the information of the detectors of the V-phase and the W-phase. The current controller selects the deviation of the d-axis current wherein the absolute value of the deviation between the d-axis current command and the first to the fourth axis current is minimized to feed it back to the d-axis current controller, and selects the deviation of the q-axis current wherein the absolute value of the deviation between the q-axis current command and the first to the fourth q-axis current is minimized to feed it back to the q-axis current controller. <P>COPYRIGHT: (C)2008,JPO&INPIT |
