| 摘要 |
<P>PROBLEM TO BE SOLVED: To surely decelerate a speed by making a stable estimation of the speed down to the extremely low-speed region in a speed censor-less vector control system of the induction motor. <P>SOLUTION: In the drive control arrangement of the induction motor, comprising a power converter 4 driving the induction motor 5, a current detection means 6 detecting an AC current supplied to the induction motor, a conversion means 7 converting the detected AC current into a current of flux axis (d-axis) component (hereinafter d-axis current) of rotating field coordinate system and a current of component (hereinafter q-axis current) orthogonal to the d-axis, a first speed estimation means 11, 12 generating a speed estimation value Fr from the q-axis current Iq, and a means 1, 3 drive controlling the induction motor based on the speed estimation value, a second speed estimation means 10, 12 generating a speed estimation value from a d-axis current command value Id* and a q-axis current command value Iq* are provided, to control the induction motor by switching the speed estimation means to the second speed estimation means when the speed estimation value is generated in a prescribed value or less during decelerating operation. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
