| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rotational position detector for a rotating machine where the accuracy in positional detection does not deteriorate depending upon the magnitude of a detected magnetic flux. <P>SOLUTION: In the rotational position detector 104, a threshold calculator 116 receives a field current If from a current sensor 112, and decides the threshold Hth for deciding the logical level of positional signals Pu*, Pv*, and Pw*, according to the magnitude of a field current If, so that the duty ratio of each positional signal Pu*, Pv*, and Pw* which shows the rotational position of a rotor may be constant. A judgement part 118 receives leaked magnetic flux Hu, Hv, and Hw and threshold Hth each from a magnetic detector 110 and a threshold calculator 116, compares each of the leaked magnetic flux Hu, Hv, and Hw with the threshold Hth, converts it into a digital signal, and outputs the converted digital signals as positional signals Pu*, Pv*, and Pw*. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
