| 摘要 |
<P>PROBLEM TO BE SOLVED: To carry out F/B control (FeedBack control), if only one phase of motor winding is broken, by using the windings in the other phases. <P>SOLUTION: Presence or absence of a breaking in the winding 33 in each phase is determined based on the output voltage of a break detection circuit 60 for each phase. If the breaking is detected in any one phase when F/B control is started, a first conducting phase is established from among the two phases in which no breaking is detected. More specifically, in terms of the order of conducting phase switching, the phase to which the conducting phase is to be switched next to the phase in which the breaking has been detected (wire-broken phase) is established as the first conducting phase. Thus, the following advantages are brought: the number of times of conducting phase switching (number of times of excitation) after F/B control is started and before the wire-broken phase is selected as conducting phase can be maximized; the rotation of a rotor can be sufficiently raised to sufficiently increase the inertia force of the rotor before the wire-broken phase becomes the conducting phase; and F/B control can be carried out with reliability. <P>COPYRIGHT: (C)2004,JPO |
