340 results about "Reluctance torque" patented technology

A magnetic gap is provided between a permanent magnet of a rotor and an auxiliary magnetic 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.

In an electric motor, such as a DC brushless motor or the like, having a permanent magnet in a rotor, each magnetic pole is formed of three permanent magnets, and the permanent magnets are made of at least two kinds of magnetic materials represented by ferrite magnet and rare-earth magnet. Thus, in a permanent magnet rotor type electric motor, a reluctance torque and a magnetic flux density can be selectively established, and cost is reasonable, corresponding to the quality.

A low-ripple multi-phase internal rotor motor has a slotted stator (28) separated by an air gap (39) from a central rotor (36). The rotor has a plurality of permanent magnets (214), preferably neodymium-boron, arranged in pockets (204) formed in a lamination stack (37), thereby defining a plurality of poles (206) separated by respective gaps (210). In a preferred embodiment, the motor is three-phase, with four rotor poles and six stator poles. As a result, when the first and third rotor poles are so aligned, with respect to their opposing stator poles, as to generate a reluctance torque, the second and fourth rotor poles are aligned to generate oppositely phased reluctance torques, so that these torques cancel each other, and essentially no net reluctance torque is exerted on the rotor. In order to magnetically separate the rotor magnets from each other, a hollow space (224, 238) is formed at the interpolar-gap-adjacent end face (216, 218) of each rotor magnet. A control circuit (147) provides electronic commutation and current control, based on rotor position signals generated with the aid of a control magnet (110) on the rotor shaft (40).

A system and method of controlling the power factor for providing either unity, leading or lagging results for the sensorless control of synchronous machines. The system and method provides an estimated angle of the phase current Park vector and uses a floating synchronous reference frame that is shifted from the estimated angle of the phase current Park vector by an angle β to allow the active control and change of the power factor during operation for applications such as producing reluctance torque of a salient pole synchronous machine during Main Engine Start (MES), and field weakening for Environmental Control Systems (ECS) and MES applications.

A system and method for using reluctance torque or a combination of both reluctance and reaction torque components of an attached synchronous machine (102) to accelerate a prime mover (116), such as a gas turbine engine, within a desired start time. The system selects a mode of starting operation, and thereafter applies reluctance torque through a synchronous machine (102) armature winding (102A) excitation as a single, sufficient starting force in a first mode, or staged reluctance and reaction torque through the additional excitation of the synchronous machine (102) field winding (102B) excitation in a second mode, using existing power electronics and controls.

A synchronous machine comprises a stator and a rotor that faces the stator and rotates on a shaft thereof in a circumferential direction The rotor has magnetic salient poles that generate reluctance torque and magnet-originating magnetic poles that generate magnet torque by using permanent magnets embedded in the rotor, The machine comprises means for shifting a magnetically substantial central position of magnetic flux emanating from the permanent magnets in the circumferential direction, by an electrical angle π/2 plus a predetermined angle Δθ, from a reference position taken as a central position between paired magnetic salient poles composing each magnetic pole of the machine among the magnetic salient poles. Hence a maximum amplitude of a sum between a harmonic component of the magnet torque and the reluctance torque is changed from that obtained at the reference position without the shift.

The Lundell motor apparatus includes a controller for controlling a field current passed to a field coil of a Lundell-type rotor of a motor and an armature current passed to a stator coil of the motor in order to generate a required torque. When the field current is If, the armature current is Ia, a d-axis inductance is Ld, a q-axis inductance is Lq, a q-axis current as a q-axis component of the armature current is Iq, a d-axis current as a d-axis component of the armature current is Id, a field torque is Tf, a field flux is Φf, a reluctance torque is Tr, and a combined torque of the field torque and the reluctance torque is ΣT, the controller passes the d-axis current Id to the stator coil within a phase angle range in which the combined torque ΣT become larger than the field torque Tf in order to generate the reluctance torque Tr which is equal to (Ld−Lq)Id·Iq in addition to the field torque Tf.

There are problems in a rotor having a slit that it is difficult to increase the number of rotations of the rotor, since the centrifugal force is received at both ends of the slit, and if the connection part is made thick to increase the number of rotations, the properties of the motor is deteriorated. According to the present invention, a rotor for a synchronous motor includes a slot for generating induction torque and a slit for generating reluctance torque, the slit is filled with a filler, the slit is provided with at least one of a convex and a concave, so that the convex and the concave are formed so as to receive the centrifugal force which is generated by the rotation of the rotor and acts on a part of the rotor outside the slit and the filler so as to bulge toward the outside from the center side of the rotor by mechanical bondage of the filler and the rotor core.

The invention relates to a double-layer V-shaped built-in permanent magnet motor rotor for an electric automobile. Multiple groups of permanent magnet slots which are radially arranged in an inner layer and an outer layer are uniformly arranged on the iron core of the rotor at intervals along the circumferential direction; one or more V-shaped magnetized stripy magnetic steel is embedded in each permanent magnet slot. By virtue of the optimization of structures such as the angle of polar arc of inner-layer V-shaped magnetic steel, the included angle of outer-layer V-shaped magnetic steel, the width proportion of the inner-layer magnetic steel to the outer-layer V-shaped magnetic steel and the included angle of the outer-layer forcipated permanent magnet slot and the outer-layer magnetic steel, the air-gap flux density waveform is more approximate to the sinusoidal distribution, the harmonic component is reduced, the air-gap field waveform of the motor is improved, the fundamental wave frequency of spline torque fluctuation is improved, the spline fundamental wave and the ultraharmonics torque amplitude value are reduced, the torque fluctuation caused by splines is reduced, and the synthesis torque fluctuation of the motor is greatly reduced; and meanwhile, the reluctance torque is obviously increased, the salient pole rate and flux weakening speed expanding capability of the motor are improved, a constant-power speed range wider than that of a surface-mounted permanent magnet motor can be obtained, and the driving requirement of electric and hybrid automobiles can be met.

The invention provides a permanent magnet auxiliary synchronous reluctance motor and a mounting method thereof. The permanent magnet auxiliary synchronous reluctance motor comprises a stator and a rotor, wherein the stator comprises a stator iron core and a concentrated winding, and the stator iron core comprises a plurality of convex magnetic poles; the convex magnetic poles comprise magnetic pole teeth and tooth boots, and the widths of the tooth boots are larger than the widths Lc of the magnetic pole teeth; the rotor comprises a rotor iron core and a plurality of permanent magnet groups, and a plurality of permanent magnet slot groups are uniformly distributed on the rotor iron cores; each permanent magnet slot group comprises at least two layers of permanent magnet slots, and each permanent magnet group comprises a permanent magnet arranged in a corresponding permanent magnet slot; the permanent magnets in each permanent magnet slot group have the same polarity, and the polarities of two adjacent permanent magnet groups are opposite; and a relation between a minimum interlayer distance g between two adjacent layers of permanent magnets in each permanent magnet group and the widths T of the tooth boots is disclosed in the specification. According to the permanent magnet auxiliary synchronous reluctance motor, the reluctance torque is maximally utilized, so that the efficiency of the motor reaches a higher level.

The invention discloses a brushless direct current reluctance starter generator. The generator comprises a three-phase armature winding, an exciting winding, a winding series-parallel switching switch, a stator iron core, a rotor iron core, a shaft, a position sensor, a bridge converter and a controller, wherein armature coils, wound intensively, are wound on each pole of the stator iron core; excitation coils are wound by crossing three stator poles; and the armature coils in the same phase are in series or parallel connection to form a group. According to the starter generator, a reluctance structure is used; no winding is generated on the rotor; the generator is simple in structure and reliable to operate; excitation current can be adjusted to keep stability of output voltage during generating; when the generator is started, the generator rotates by means of a reluctance torque; the armature coils are connected in series; a large starting torque is achieved; the generator is applicable to operation at a low speed; the excitation winding is used for generating a magnetic field during generating; the armature coils are connected in parallel; small armature reaction is generated; and the generator is applicable to operation in a high speed. The brushless direct current reluctance starter generator is very applicable to transport tools comprising vehicles.

A bridge (8) in conformity with a tooth opening angle of the stator (1) is provided between a permanent magnet (5) and a permanent magnet (5) in a rotor (4), so that a magnetic flux for a reluctance torque is made to pass an inner side of the permanent magnet (5). An opening angle of each of ribs (7) on both sides of the permanent magnet (5) is set to be equal to or smaller than the teeth interval opening angle and equal to or larger than a half thereof. Thereby, reluctance of the rib (7) against a magnetic flux in a circumferential direction is increased and leakage of the magnetic flux of the permanent magnet (5) is prevented.

An axial motor includes a rotor arranged between a pair of stators with coils. In the rotor, a plurality of permanent magnets sandwiched between pairs of first magnetic materials and a plurality of second magnetic materials are alternately arranged in a rotation direction while gaps are provided therebetween. Since the permanent magnets are sandwiched by the first magnetic materials in the thus constructed axial motor, a field-weakening control can be performed. Since the second magnetic materials are provided, a reluctance torque can be generated. Further, since the gaps are provided, more magnetic fluxes generated from the permanent magnets can be caused to flow toward the coils. Therefore, the thus constructed axial motor can achieve a higher output, higher torque, higher efficiency, and miniaturization.

A Darrieus rotor supported by a bearing system to rotate about a vertical axis for capturing wind energy has an alternator that is directly-driven by the rotor and converts rotational power from the rotor into electrical power. An electronic controller controls the electrical load applied to the alternator and the power output from the alternator to an output. The alternator is constructed having a substantially constant reluctance torque for all angular positions of rotation of the rotor. The bearing system includes upper and lower rolling element mechanical bearings that provide radial support of the rotor against wind load and axial support of the rotor, and a magnetic bearing that provides axial lift that reduces the axial load on the mechanical bearings and reduces the starting torque for rotating the rotor. The electronic controller applies minimal electrical load to the alternator until the rotor is at a rotational speed greater than a deadband for the rotor in the instantaneous wind speed, whereby the electronic controller, the alternator and the bearing system together avoid retarding forces that would otherwise prevent passive self-starting.

The invention provides a reluctance type alternating pole permanent magnet motor, which comprises a rotor, wherein the rotor is provided with at least two permanent magnet poles which take an axis ofthe rotor as a center and are uniformly distributed along the circumferential direction of the rotor, each permanent magnet pole comprises inner-layer magnetic slots and outer-layer magnetic slots which are sequentially arranged and mutually separated along the radial direction of the rotor; and each inner-layer magnetic slot is internally provided with an inner-layer permanent magnet matched withthe inner-layer magnetic slot, and each outer-layer magnetic slot is internally provided with an outer-layer permanent magnet matched with the outer-layer magnetic slot. The reluctance type alternating pole permanent magnet motor has the advantages that the difference between q-axis inductance and d-axis inductance can be improved, thus the reluctance torque is enabled to be fully utilized, and the electromagnetic torque is enabled to be improved.

The invention relates to a permanent magnet reluctance type in-wheel motor, which comprises an outer rotor and an inner stator, wherein a three-phase winding is arranged on the inner stator; magnetic steel is uniformly distributed along the circumferential direction of the outer rotor; the permanent magnet reluctance type in-wheel motor is characterized in that grooves arranged at intervals are formed on the inner circumferential surface of the outer rotor; the magnetic steel is embedded inside the grooves; the cross section of the magnetic steel is rectangular; the polarity of all magnetic steel facing to the inner stator is the same; a magnetic conduction salient pole is formed between adjacent grooves; the magnetic conduction salient poles and the magnetic steel are arranged alternately at intervals; the curve of the cross section of the magnetic conduction salient pole facing to one side end of the inner stator is convex arc-shaped; and the number of grooves and the number of magnetic poles in the outer rotor adopt the combination with close grooves. The permanent magnet reluctance type in-wheel motor has the advantages that the using amount of magnetic steel can be efficiently reduced and the output of reluctance torque is improved under the precondition of not increasing process complexity; and the magnetic conduction salient poles adopt arc-shaped convex surfaces, so that the motor torque pulsation is efficiently reduced, the stability of motor running is ensured, and the product reliability is improved.

The present invention provides an S SRM (switched reluctance machine), which supports one or more phases and each phase comprises a stator, a rotor and coils. The stator is hollow, cylindrical and comprises stator poles extending inwards, such that a recess is formed between adjacent stator poles. The coils are wound on the stator poles and occupy the recess. The rotor is positioned inside the stator and has poles extending outwards. The rotor and stator poles subtend an angle having a maximum value of 0.5 electrical pole pitches at a center of rotation. The different phases are distributed along the axis of the S SRM. The rotor is rotated by a reluctance torque generated by energizing a phase in a current controlled manner until the rotor rotates through a minimum commutation angle required to maintain motion; de-energizing the phase by freewheeling it by using the energy stored in it and simultaneously energizing a second sequentially adjacent phase.

The invention discloses a permanent magnet reluctance synchronous motor rotor structure having high torque density. The permanent magnet reluctance synchronous motor rotor structure comprises a central rotating shaft and a rotor iron core; the rotor iron core is uniformly provided with P groups of through grooves along the circumferential direction; each group of through grooves comprises three layers of U-shaped through grooves arranged in the radial direction of the rotor iron core at intervals; and a permanent magnet is embedded in the straight bottom side of each U-shaped through groove. By means of the permanent magnet reluctance synchronous motor rotor structure disclosed by the invention, the permanent magnet torque component and the reluctance torque component are sufficiently utilized in the synthesis torque of a motor; and thus, the torque density of the motor is increased.