| 摘要 |
<P>PROBLEM TO BE SOLVED: To accurately find a rotational position (a stopped electric angle) of a rotor in a magnet embedded brushless DC motor without a sensor. <P>SOLUTION: When the rotor in the IPM motor is stopped, a current for magnetically saturating a winding flows, and positive phase currents Iu, Iv, Iw and negative phase currents Iu(N), Iv(N), Iw(N) are found. Intervals I-III are determined by determining the maximum among the phase currents Iu, Iv, Iw. In the determined zones, the rotational position of the rotor is determined based on the degree of deviation of "a difference between the maximum phase current and the second-maximum phase current" and "a difference between the second-maximum phase current and the minimum phase current" among the phase currents Iu, Iv, Iw. <P>COPYRIGHT: (C)2007,JPO&INPIT |
