| 摘要 |
Disclosed is a magnetic flux concentrated-type brushless motor performing field weakening control and reducing iron loss. The teeth of the stator are provided with a stator-side wide-width portion, and the rotor is provided with magnetic members having a rotor-side wide-width portion, and magnets disposed between the magnetic members. The motor is driven for a certain time in a low rate of rotation (LRR) section and a high rate of rotation (HRR) section. Field weakening control is performed in the HRR section. When the number of pairs of opposite poles of the rotor is P, a length of a radial line of the rotor-side wide-width portion R, a thickness of the stator-side wide-width portion Lt, a central angle of the stator-side wide-width portion τt, a central angle the rotor-side wide-width portion τr, and a central angle between any two neighboring magnets τM, the motor is set such that τr≦2.85×τm−2.65×τt and (Lt×P)/(ττ×R)≧τt/τm−0.6. |
| 主权项 |
1. A brushless motor comprising a rotor rotatable about an axis of rotation, and a stator disposed inside or outside the rotor,
wherein: the stator comprises a yoke provided with a circumferential surface having a ring-shaped cross section and facing the rotor, and a plurality of teeth, each of the teeth radially protruding from the circumferential surface of the yoke toward the rotor and being provided, at a protruding end thereof, with a stator-side wide-width portion having both lateral sides protruding to form a widened width; and the rotor comprises a plurality of magnetic members, each of the magnetic members being provided with a rotor-side wide-width portion radially disposed at a circumferential edge of the rotor to face the stator and provided, at a stator-side end thereof, with both lateral sides protruding to form a widened width, and a plurality of magnets, each of the magnets being disposed between neighboring ones of the magnetic members such that the same magnetic poles face each other in a circumferential direction, wherein, when a number of pairs of opposite poles of the rotor is P, a length of a radial line connecting a cross-sectional surface of the rotor-side wide-width portion to the axis of rotation is R, a radial thickness of the stator-side wide-width portion is Lt, a central angle between two radial lines connecting both circumferential ends of the stator-side wide-width portion to the axis of rotation is τt, a central angle between two radial lines connecting both circumferential ends of the rotor-side wide-width portion to the axis of rotation is τr, and a central angle between two radial lines connecting centers of any two neighboring magnets to the axis of rotation is τm, the motor is set such that
τr≦2.85×τm−2.65×τt and (Lt×P)/(ττ×R)≧τt/τm−0.6. |
