Abstract: A rotating electric machine includes: a rotary shaft member; a rotor including an annular rotor core having magnet housing holes; a stator including an annular stator core and a stator coil; a field yoke; and a field coil provided in the field yoke. Further, a bridge portion is provided between two magnet housing holes, an end surface in an axial direction at one end in a radial direction of the field yoke and an end surface in the axial direction of the bridge portion face each other in the axial direction, and an end surface in the axial direction at another end in the radial direction of the field yoke, and an end surface in the axial direction of the rotor core or an end surface in the axial direction of the stator core face each other in the axial direction.

Abstract: A rotary electric machine includes a rotor and a stator. The stator has windings and teeth extending radially from a stator core. Each tooth is separated from an adjacent tooth by a stator slot that opens to a radial stator-rotor airgap via a slot opening. The windings are positioned within each slot. Each stator tooth has a tooth tip with a surface profile configured to guide rotor flux away from areas of the windings proximate the respective slot opening. The tip surface profile may be a concave region, e.g., a dent/chamfer, and/or a convex region, e.g., a bump/bulge, and is formed in a distal end surface of the tip proximate the opening. The stator-rotor airgap is smaller at the convex region and larger at the concave region than elsewhere along the distal end surface. An electrical system includes the machine, a battery, and a power inverter module.

Abstract: The invention relates to an electric machine comprising a rotor (10) and a stator (20). The rotor (10) has magnet pockets for receiving permanent magnets (55, 56, 85, 86), and the magnet pockets comprise at least one first pair of magnet pockets (50, 51) and a second pair of magnet pockets (80, 11). The second pair (80, 81) is arranged further inwards than the first pair (50, 51) when viewed in a radial direction with respect to a rotational axis, and the magnet pockets of each pair of magnet pockets (50, 51, 80, 81) are arranged symmetrically to one another with respect to an axis of symmetry (45), wherein the axis of symmetry (45) runs in the radial direction and through the center of the rotor (10). The magnet pockets of each pair of magnet pockets (50, 51, 80, 81) are arranged such that the distance of each magnet pocket to the axis of symmetry (45) increases as the distance to the circumferential edge (110) of the rotor (10) decreases.

Abstract: A motor driving apparatus includes a motor and a control circuit that controls driving of the motor. The motor includes a rotor having a cylindrical magnet having an outer peripheral surface circumferentially divided and alternately multi-polar magnetized to different poles, a first and second yokes having first and second magnetic pole portions arranged opposed to the outer peripheral surface, a first and second coils energized to excite the first and second magnetic pole portions, respectively. Directions of energizing the first and second coils are switched based on outputs from magnetic sensors that detect a rotational position of the rotor to change excited poles of the first and second magnetic pole portions. The rotor is started from a stopped state, after performing direct current energization to move the rotor to a position dependent on the direct current energization.

Abstract: The invention describes an electrical machine comprising a stator and a rotor which is separated from the stator by an air gap and has a plurality of shell-like magnet segments which are fastened to a magnetic return path element. In this case, the magnet segments are arranged opposite one another in pairs in each case and each have a plurality of magnetically differently polarized sections in the circumferential direction, said sections each forming a magnetic pole of the rotor. In this case, recesses which each serve as outer detached pole portions are provided on that side which faces the stator in the edge zones of the magnet segments which are arranged in the circumferential direction. Furthermore, further recesses are provided on that side which faces the stator in the transition zones between the magnetically differently polarized sections of the magnet segments, said recesses serving as inner detached pole portions.

Abstract: In a pump, a resin magnet included in a rotor portion has a plurality of groove portions in an outer peripheral portion thereof, the groove portions extending in an axial direction.

Abstract: An interior permanent magnet machine is described. The machine includes a rotor rotatable about a central machine axis. The rotor includes a plurality of permanent magnet openings and a plurality of permanent magnets disposed therein. The permanent magnet openings are separated by rotor webs configured to facilitate reducing leakage flux through the rotor webs. The machine also includes a stator disposed coaxially with the rotor and separated from the rotor by a circumferential air gap. The stator includes a plurality of stator teeth that define a plurality of stator slots therebetween. The stator teeth include a stator tooth tip configured to facilitate reducing cogging torque and torque ripple.

Abstract: A three-phase rotating electrical machine includes a stator including a stator core provided with a plurality of teeth and a plurality of slots, and winding, the three-phase rotating electrical machine including a rotor including a rotor core and a north magnetic pole and a south magnetic pole, the three-phase rotating electrical machine including a fractional slot configuration, the rotor core including a north magnetic pole acting portion, a south magnetic pole acting portion, a magnetic pole boundary dividing the north magnetic pole acting portion and the south magnetic pole acting portion in the circumferential direction, and a magnetic resistance portion, the magnetic resistance portion restricting the magnetic flux from passing through.

Abstract: An actuator assembly includes an electric motor including a rotor assembly and a stator assembly configured to be actuated to cause the rotor assembly to rotate based on an amount of magnetic flux in the rotor assembly is disclosed. The assembly also includes a controllable magnetic device coupled to the rotor assembly, an actuator coupled to the rotor assembly; and a controller configured to apply electric current to the controllable magnetic device to adjust an amount of torque provided by the electric motor by adjusting the magnetic flux in the rotor assembly.

Abstract: A single-phase outer-rotor motor and a stator thereof are provided. The stator includes a stator core having a yoke and a number of teeth. Each tooth includes a tooth body and a tooth tip. A winding slot is formed between each two adjacent tooth bodies. A slot opening is formed between each two adjacent tooth tips. The tooth tip protrudes beyond the tooth body. Inner surfaces of at least part of the tooth tips facing the stator are formed with cutting grooves such that a portion of the tooth tip outside the cutting groove is capable of being tilted outwardly to enlarge the slot opening and deformed inwardly to narrow the slot opening.

Abstract: A resin magnet, a magnetic pole position detection resin magnet, and a sleeve bearing, which is disposed inside the resin magnet, are integrally molded together with a thermoplastic resin in a rotor portion. At the same time, an impeller attachment portion is formed by the thermoplastic resin.

Abstract: An embedded magnet motor includes a stator core, a plurality of permanent magnets each having a rectangular cross section, and a rotor core. The stator core and the rotor core define a first air gap being positioned at an intermediate portion of the rotor core, a second air gap being positioned at a first portion corresponding to a first axis of the rotor core, and a third air gap being positioned at a second portion corresponding to a second axis of the rotor core. Because a diameter of the intermediate portion being positioned between the first portion and the second portion of the rotor core is set smaller than a diameter of the first portion and than a diameter of the second portion, the first air gap is set greater than the second air gap and than the third air gap.

Abstract: A pump is provided that includes a molded stator having a substrate on which is mounted a magnetic-pole position detection element and that also includes a rotor having a rotor unit with one end thereof in an axial direction being opposed to the magnetic-pole position detection element and the other end thereof in the axial direction being provided with an impeller attachment unit. The rotor unit includes a magnet, a sleeve bearing, and a resin portion formed from a thermoplastic resin that is used for integrally molding the magnet and the sleeve bearing and that constitutes the impeller attachment unit. The magnet includes a plurality of through holes that each extend in the axial direction; and each of the through holes is embedded in the thermoplastic resin that constitutes a part of the resin portion.

Abstract: A dynamoelectric machine includes a rotor having a rotor core and permanent magnets, and a stator having teeth. The permanent magnets are arranged in magnet sets. Each magnet set includes one or more of the permanent magnets. The rotor core has a cylindrical periphery and slits. Each of the slits is positioned radially between one of the magnet sets and the cylindrical periphery. Each tooth includes a tooth surface facing the cylindrical periphery. The tooth surface includes an inner portion extending substantially parallel to the cylindrical periphery of the rotor core, and beveled portions positioned on opposing sides of the inner portion of the tooth surface. An air gap between each beveled portion of the tooth surface and the cylindrical periphery of the rotor core is greater than an air gap between the inner portion of the tooth surface and the cylindrical periphery of the rotor core.

Abstract: A brushless motor includes a stator comprising a stator core with teeth protruding inwardly and windings wound on the teeth, and a rotor comprising a shaft, a rotor core fixed to the shaft, and a ring magnet fixed to the circumferential outer surface of the rotor core. The ring magnet includes a plurality of magnetic poles radially magnetized so that north poles and south poles are arranged alternately in the circumferential direction, boundary lines between adjacent magnetic poles being skewed by an angle ? relative to an axis of the shaft. A plurality of grooves are formed in a circumferential outer surface of the rotor core. Each groove extends from one axial end to the other axial end of the rotor core, has a circumferential width smaller than each of the magnetic poles, and is covered by the ring magnet with a void formed between the groove and the ring magnet.

Abstract: In a double-stator motor has a rotary shaft, an annular rotor is coupled with a rotary shaft. First and second three-phase stators are arranged inside and outside to the rotor in the radial direction and formed to generate first and second rotating magnetic fields in response to three-phase currents, respectively. The rotor has an even number of segment poles made of soft magnetic material and arranged mutually separately at positions of the rotor. The positions are equally distanced apart from the rotary shaft in the radial direction and in the circumferential direction. Each of the first and second three-phase stators has magnetic poles which are the same in the number of poles as the segment poles and the magnetic poles are positioned such that magnetomotive forces from the magnetic poles are faced to each other between the magnetic poles of the first and second three-phase stators.

Abstract: A rotor includes first and second permanent magnets provided in each magnetic pole inside a rotor core. The rotor is configured such that when a first end of the first permanent magnet located on the outer circumferential side of the rotor core and the second permanent magnet side is located at a position that faces a first end in the circumferential direction of one of teeth of a stator, a second end of the first permanent magnet located on the axis of rotation side of the rotor core and the second permanent magnet side is located at a position that faces a second end in the circumferential direction of the tooth that faces the first end of the first permanent magnet.

Abstract: A permanent-magnetic type rotary electric machine includes a stator having teeth that are arranged in the peripheral direction thereof and around which armature windings of plural phases are wound, and a rotor having plural permanent magnets arranged so that the poles of the permanent magnets are alternately different in the peripheral direction thereof, higher harmonic waves being contained in a no-load induced voltage waveform. A (6p?1)-th higher harmonic wave and a (6p?1)-th higher harmonic wave (p represents a positive integer) when an electrical angle of 360° is set as a fundamental wave in the no-load induced voltage waveform are made substantially coincident with each other in amplitude and phase.

Abstract: An electric motor (1) has a stator (2) and a radially symmetric, permanent magnet excited rotor (4) coaxial with the stator (2). The rotor (4) rotates relative to the stator (2) about a common motor axis (X). The stator (2) has a radially symmetric iron core (6) with a defined number (N) of stator teeth (10) which are each adjacent to one another via stator slots (8) and slot openings (8a) in the circumferential direction. The rotor (4) has pole magnets (14) adjacent to one another. A circumferential gap (18) is formed radially between the pole magnets (14) and the stator teeth (10). Each stator tooth (10) has on its surface (20) facing the gap (18) and adjacent to the slot openings (8a) on both sides in the circumferential direction a relief-like topographic region (22) radially enlarging the gap (18) with least one concave recess (24) and a smooth profile.

Abstract: A stator and a rotor are oppositely arranged having a gap between the stator and the rotor in a direction parallel to a rotary shaft. The rotor has permanent magnets forming field magnetic poles and soft magnetic material segments to cover at least stator-facing surfaces of the respective permanent magnets. Each of the soft magnetic materials forms a composite part together with the permanent magnet. The rotor further has a disc-shaped nonmagnetic molded frame molded so as to cover the periphery of the composite part including the permanent magnet and the soft magnetic material segment while leaving a stator-facing surface of the soft magnetic material segment as an exposed surface. The composite part (including the permanent magnet and the soft magnetic material) and the nonmagnetic molded frame are integrated by molding of the molded material.

Abstract: The permanent magnet embedded rotating electrical machine includes a rotor and a plurality of flat permanent magnets. The rotor has on an outer periphery thereof a plurality of pairs of concave portions and a plurality of convex portions. Each of the convex portions is located between the pair of concave portions. The concave portions are formed at radially outward of respective adjacent magnetic pole ends of the permanent magnet. A bridge is provided in the rotor at an angular position about an axis of the rotor between opposed magnetic pole ends of two adjacent permanent magnets. Each concave portion at radially outward of the magnetic pole end of the permanent magnet is located close to the center of the same permanent magnet in relation to the bridge next to the permanent magnet in the circumferential direction of the rotor.

Abstract: Permanent-magnet (PM) rotors, rotor components, and machines using PM rotors.

Abstract: A permanent magnet rotating electric machine includes: a stator including: a stator core having teeth, and an armature winding wound around each of the teeth to configure the multiple phases; and a rotor including a rotor core, and permanent magnets provided in order around the rotor core. The rotor is arranged to be spaced apart from the stator with an air gap therebetween. Each of the permanent magnets has a curved surface opposed to the stator and is configured to satisfy the following relationship: 0.65 ? Rm × h ? ? 1 W ? ( h ? ? 1 + g ) ? 1.37 where Rm denotes a radius of curvature of the curved surface, h1 denotes a thickness of a central portion of the permanent magnet in the peripheral direction, W denotes a width of the permanent magnet in the peripheral direction, and g denotes an air gap length of the air gap.

Abstract: An automotive embedded permanent magnet rotary electric machine can suppress increases in torque ripples and cogging torque, reduce core loss near a stator, and increase magnetic torque and reluctance torque. In the automotive embedded permanent magnet rotary electric machine, a first permanent magnet and a second permanent magnet that constitute a magnetic pole are embedded so as to line up in a main direction of rotation of magnetic poles of a rotor core and are embedded so as to be radially outwardly convex in a region that extends from a leading end portion to a trailing end portion in the main direction of rotation of the magnetic poles, and the first permanent magnet is formed into an integrated body that extends from the leading end portion in the main direction of rotation of the magnetic poles beyond a pole center toward a trailing side.

Abstract: A rotor structure for an interior permanent magnet (IPM) electromotive machine is provided. The rotor structure may include at least one rotor lamination, which in turn may include at least one slot arranged to receive at least one permanent magnet. The slot divides the rotor lamination into a pole region and a yoke region. At least one bridge is arranged to connect the pole region to the yoke region at an outer edge of the lamination. The outer edge of the lamination is profiled along a segment of the bridge to define a concave curved profile for the bridge. The concave curved profile for the bridge allows to selectively size a thickness of the bridge to affect at least some electromagnetic and/or mechanical characteristic of the machine.

Abstract: A permanent magnet motor includes: a rotor and a stator; and a plurality of permanent magnets placed on either the rotor or the stator. Each permanent magnet is an R—Fe—B based rare-earth sintered magnet including a light rare-earth element RL (at least one of Nd and Pr) as a major rare-earth element R, and partially includes a high coercivity portion in which a heavy rare-earth element RH (at least one element selected from the group consisting of Dy, Ho and Tb) is diffused in a relatively higher concentration than in the other portion.

Abstract: An interior permanent magnet type brushless direct current (BLDC) motor includes a stator having a plurality of slots and a stator coil wound on the slots. The interior permanent magnet type brushless direct current (BLDC) motor also includes a rotor that rotates with respect to the stator and that has a rotor core and a plurality of permanent magnets positioned in the rotor core. The rotor has a notch that is cut off between adjacent permanent magnets.

Abstract: Supposing a straight line joining rotation center O of a rotor and a magnetic pole middle, that is, a middle of permanent magnets (25) to be a d-axis, and a straight line joining rotation center O and an intermediate point of mutually adjacent permanent magnets (25) to be a q-axis, mutually adjacent arcs A1 and A2 are composed such that radius R1 of arc A1 at the d-axis side is larger than radius R2 of arc A2 at the q-axis side, and that, at intersection point ? of mutual arcs A1 and A2, angle ? of tangent u of arc A2 at the q-axis side with respect to tangent t of arc A1 at the d-axis side is set by ?3 degrees???2 degrees.

Abstract: Embodiments of the invention provide for conical magnets for rotors in electrodynamic machines, methods to design the same, and rotor-stator structures for electrodynamic machines. In various embodiments, a rotor-stator structure for electrodynamic machine can include field pole members and conical magnets. According to at least some embodiments, one or more of the conical magnets can include a magnetic region configured to confront one or more air gaps. The magnetic region can be substantially coextensive with one or more acute angles to the axis of rotation. The magnetic region can also include a surface positioned at multiple radial distances from the axis of rotation in a plane perpendicular to the axis of rotation.

Abstract: To reduce the cogging torque of servomotors, electric power steering motors, and others, there is provided a permanent magnet motor comprising: a rotor 10 comprising a rotor yoke 11 and a plurality of permanent magnets (M1-M10); and a stator 20 comprising a stator yoke 22, salient magnetic poles 21, and armature windings 23, wherein at least one of the permanent magnets is disposed in an adjustment position that is displaced from a corresponding reference position in at least one of the circumferential, radial, and axial directions of the rotor yoke, and the plurality of permanent magnets excluding the permanent magnet disposed in the adjustment position is disposed in the reference positions, and wherein the adjustment position is set so that the permanent magnet motor in which at least one of the plurality of permanent magnets is disposed in the adjustment position has a smaller cogging torque than a permanent magnet motor in which all of the plurality of permanent magnets are disposed in the reference posi

Abstract: An electrical machine including a permanent magnet and a coil is provided. The coil is arranged to interact with the permanent magnet via an air gap, which located between the two. Electrical power is generated in the coil when the permanent magnet or the coil is moved in their relative position to each other. The permanent magnet includes a surface, which is aligned to the coil and to the air gap so that that magnetic forces of the permanent magnet interact via the surface and the air gap with the coil by a magnetic flux density distribution. The permanent magnet also includes a base plane and a transition area. A first side of the surface is connected with the adjacent base plane via the transition area. The cross-section of the transition between the surface and the adjacent base plane is determined by a Bezier function.

Abstract: A rotor is provided. The rotor includes a rotor iron core including slots formed around an outer circumferential portion thereof; magnet pieces which are inserted into the slots, respectively, such that a magnetic orientation of the magnet pieces are inverted every predetermined number of the slots; and two end plates, one end plate disposed on each end side in an axial direction of the rotor iron core, the two end plates covering the slots in the axial direction. The rotor iron core also includes cutout portions, which are located at an interval between adjacent ones of the slots, each of the cutout portions extending in the axial direction of the rotor iron core. One of the two end plates includes injection openings, each of which corresponds to a respective one of the slots, and communicating grooves each of which is formed so as to communicate with one of the cutout portions.

Abstract: An electric motor (1) has a stator (2) and a radially symmetric, permanent magnet excited rotor (4) coaxial with the stator (2). The rotor (4) rotates relative to the stator (2) about a common motor axis (X). The stator (2) has a radially symmetric iron core (6) with a defined number (N) of stator teeth (10) which are each adjacent to one another via stator slots (8) and slot openings (8a) in the circumferential direction. The rotor (4) has pole magnets (14) adjacent to one another. A circumferential gap (18) is formed radially between the pole magnets (14) and the stator teeth (10). Each stator tooth (10) has on its surface (20) facing the gap (18) and adjacent to the slot openings (8a) on both sides in the circumferential direction a relief-like topographic region (22) radially enlarging the gap (18) with least one concave recess (24) and a smooth profile.

Abstract: An electrical machine including a permanent magnet and a coil is provided. The coil is arranged to interact with the permanent magnet via an air gap, which located between the two. Electrical power is generated in the coil when the permanent magnet or the coil is moved in their relative position to each other. The permanent magnet includes a surface, which is aligned to the coil and to the air gap so that that magnetic forces of the permanent magnet interact via the surface and the air gap with the coil by a magnetic flux density distribution. The permanent magnet also includes a base plane and a transition area. A first side of the surface is connected with the adjacent base plane via the transition area. The cross-section of the transition between the surface and the adjacent base plane is determined by a Bezier function.

Abstract: An electrical machine including a permanent magnet and a coil is provided. The coil is arranged to interact with the permanent magnet via an air gap, which located between the two. The permanent magnet includes a surface, which is aligned to the coil and to the air gap so that that magnetic forces of the permanent magnet interact via the surface and the air gap with the coil by a magnetic flux density distribution. The surface has a cross-section having a shape that approximates at least partly to a sinusoidal function, causing the magnetic flux distribution in the air gap to be substantially sinusoidal.

Abstract: Embodiments of the invention provide for conical magnets for rotors in electrodynamic machines, methods to design the same, and rotor-stator structures for electrodynamic machines. In various embodiments, a rotor-stator structure for electrodynamic machine can include field pole members and conical magnets. According to at least some embodiments, one or more of the conical magnets can include a magnetic region configured to confront one or more air gaps. The magnetic region can be substantially coextensive with one or more acute angles to the axis of rotation. The magnetic region can also include a surface positioned at multiple radial distances from the axis of rotation in a plane perpendicular to the axis of rotation.

Abstract: To reduce the cogging torque of servomotors, electric power steering motors, and others, there is provided a permanent magnet motor comprising: a rotor 10 comprising a rotor yoke 11 and a plurality of permanent magnets (M1-M10); and a stator 20 comprising a stator yoke 22, salient magnetic poles 21, and armature windings 23, wherein at least one of the permanent magnets is disposed in an adjustment position that is displaced from a corresponding reference position in at least one of the circumferential, radial, and axial directions of the rotor yoke, and the plurality of permanent magnets excluding the permanent magnet disposed in the adjustment position is disposed in the reference positions, and wherein the adjustment position is set so that the permanent magnet motor in which at least one of the plurality of permanent magnets is disposed in the adjustment position has a smaller cogging torque than a permanent magnet motor in which all of the plurality of permanent magnets are disposed in the reference posi

Abstract: A motor having a rotor including first outer surface segments providing uniform air gaps and second outer surface segments providing non-uniform air gaps. The rotor has an outer surface contour comprising a number of first outer surface segments defined by arcs having a first radius centered on a central longitudinal axis and a number of second outer surface segments defined by lines other than arcs having a first radius centered on a central longitudinal axis.

Abstract: A rotor for an electromotor using permanent magnets is provided. The rotor may include one or more C-type permanent magnets, a core, and a rotor shaft. Each of the one or more C-type permanent magnets may have a C shape and provide magnetic force. The core may be of a cylindrical shape and have the one or more C-type permanent magnets coupled thereto with different magnetic poles. An aperture 11 may be formed at each of the boundaries of the C-type permanent magnets having the different magnetic poles. The rotor shaft may be formed at the center of the core. Cogging torque can be reduced because a magnetic field of the C-type permanent magnets coupled through the outside core forms a normal sine wave form.

Abstract: Supposing a straight line joining rotation center O of a rotor and a magnetic pole middle, that is, a middle of permanent magnets (25) to be a d-axis, and a straight line joining rotation center O and an intermediate point of mutually adjacent permanent magnets (25) to be a q-axis, mutually adjacent arcs A1 and A2 are composed such that radius R1 of arc A1 at the d-axis side is larger than radius R2 of arc A2 at the q-axis side, and that, at intersection point ? of mutual arcs A1 and A2, angle ? of tangent u of arc A2 at the q-axis side with respect to tangent t of arc A1 at the d-axis side is set by ?3 degrees???2 degrees.

Abstract: A permanent magnet has a D-shaped cross section including an arcuate top surface (22), a flat bottom surface (24), and side surfaces (26, 28). Provided that a plurality of permanent magnets are circumferentially arranged so that a great circle (S) circumscribes the apexes (P) on the arcuate top surfaces (22), the top surface (22) includes a central region which delineates an arc of a small circle (T) off-centered from the great circle, and end regions (22a, 22b) which are positioned outside the small circle (T) and inside the great circle (S).

Abstract: A dynamoelectric machine comprising a stator having a plurality of slots and teeth, armature windings wound around the teeth, and a rotor disposed inside the stator, wherein an alloy member is disposed in the inner periphery of the stator and the magnetic compensator has its surface or inside thereof a high resistance layer.

Abstract: A rotary shaft 60 having an outside diameter larger than the bore diameter of a rotary shaft insert hole 59 of a rotor 50 is inserted into the rotary shaft insert hole 59. A magnet insert hole 51a1 is provided in a main magnetic pole [a] of the rotor 50. Permanent magnets 52a1 to 52a3 are inserted into the magnet insert hole 51a1 such that a gap is formed between the permanent magnets 52a1 to 52a3 and the magnet insert hole 51a1. A semi-tubular rivet insert hole 55a and interlocks 57a1, 57a2 elongated in the radial direction of the rotor are disposed radially outward of the magnet insert hole 51a in the rotor. A semi-tubular rivet 56a is inserted into the semi-tubular rivet insert hole 55a such that a gap is formed between the semi-tubular rivet 56a and the semi-tubular rivet insert hole 55a. Passage holes 58ab, 58da are provided in the auxiliary magnetic poles [ab], [da].

Abstract: A rotary structure of a permanent magnet electric machine including a stator and a rotor is provided. The stator has K salient teeth peripherally spaced with equal intervals for forming K winding slots, wherein K is a natural number greater than 1. The rotor has an annular inner surface and has P pairs of permanent magnets peripherally spaced with equal intervals along the inner surface for rotating around the stator, wherein P is a natural number. Each permanent magnet having two sides along a peripheral direction of the rotor includes a pair of inclined surfaces on the two sides, the pair of inclined surfaces is symmetric with respect to a radial plane of the each permanent magnet, and an inclined angle ? between the inclined surface and the radial plane is selected from a range of 90(1?1/(4P))<?<90(1+1/(4P)).

Abstract: In a magnet-exciting rotating electric machine system, a rotor surface has magnetic salient poles and island-shaped magnetic poles alternately in circumferential direction, and the island-shaped magnetic poles are constituted so that magnetic flux coming from an external source does not flow through. A magnetic excitation part magnetizes the island-shaped magnetic poles and the magnetic salient poles collectively in the same direction, and then control a flux amount flowing through an armature. The armature has armature coils that face the magnetic salient pole and the island-shaped magnetic pole simultaneously so that driving torque fluctuation or power generation voltage waveform distortion is controlled. The magnetic excitation part changes magnetization state of a field magnet irreversibly, or changes an excitation current to an excitation coil to control a flux crossing the armature.

Abstract: A three-phase dynamoelectrical permanently excited synchronous machine includes a stator with teeth which point to a rotor, wherein twelve slots are formed between the teeth. The slots have coil sides of coils of a winding system in such a manner that two coil sides of different coils are situated in each slot. The rotor has a cylindrical support structure which is provided with permanent magnets defined by an inner radius which corresponds to a radius of the support structure, and by an outer radius which is smaller than their inner radius. The permanent magnets are formed with ten magnet poles when viewed in a circumferential direction.

Abstract: An outer rotor-type fan motor and a method for magnetizing a magnet applied thereto. The outer rotor-type fan motor comprises a rotation shaft; a stator disposed outside the rotation shaft; a fan having a hub and blades formed on the hub, the hub covering the stator with a predetermined gap; and a magnet disposed on an inner surface of the hub and spaced from the stator with a predetermined gap, wherein the magnet is an isotropic magnet magnetized to have a pole anisotropy. Accordingly, a cogging torque and noise are reduced without reducing a back-electromotive force, thereby obtaining a high efficiency.

Abstract: A permanent magnet motor 1 includes a rotor in which permanent magnets 31 are fixed. In the rotor 20, the outer peripheral shape of rotor magnetic-pole portions 24 is formed so that, in the circumferentially central portion, the distance from the center of the rotor iron core 21 is longest, and, at the inter-polar space, the distance from the center of the rotor iron core is shortest, and so that the outermost surface of the rotor magnetic-pole portions 24 forms an arc, and given that sheath thickness tc formed by the outer-side surface of each permanent magnet 31 and the outermost surface of each rotor magnetic-pole portion 24 is practically constant, and letting the thickness of the permanent magnets be the magnet thickness tm, then the relation tc/tm?0.25 is satisfied.

Abstract: A magnetic gap is provided between a permanent magnet of a rotor and an auxiliary magnet pole portion which is arranged adjacent to the permanent magnet in a peripheral direction. A gradual change in a magnetic flux density distribution of a surface of the rotor is obtained and a cogging torque and a torque pulsation are restrained. By obtaining a reluctance torque according to the auxiliary magnetic pole, a permanent magnet electric rotating machine in which the cogging torque and the torque pulsation are restrained can be obtained and further an electromotive vehicle having the permanent magnet electric rotating machine can be provided.

Abstract: In a permanent magnet motor consisting of a rotor 1, which is supported on a rotating shaft 2 and has twelve permanent magnets 3 arranged at fixed intervals in the circumferential direction in the peripheral edge portion thereof, and a stator 4, which is disposed around the rotor 1 with a gap being provided with respect to the rotor 1 and has nine magnetic poles 4a, each having a coil wound thereon, arranged at fixed intervals in the circumferential direction so as to face towards the outer peripheral surface of the rotor 1, a value obtained by dividing the radius of the rotor 1 by the radius of curvature of a permanent magnet surface facing towards the stator is set at a value such as to decrease cogging torque.