318 results about "Cogging torque" patented technology

The invention provides a permanent magnet motor based on permanent magnet included angle optimization and a cogging torque suppression method thereof.The permanent magnet motor comprises a stator iron core, an armature winding, rotor iron cores and permanent magnets, and each pole of rotor iron core is provided with two sets of first V-shaped permanent magnet grooves and second V-shaped permanent magnet grooves which are symmetrical about the center line of the rotor iron core and are different in size; the permanent magnets are arranged in the first V-shaped permanent magnet grooves and the second V-shaped permanent magnet grooves respectively, the permanent magnets in the first V-shaped permanent magnet grooves and the second V-shaped permanent magnet grooves are arranged in a V-V shape, the included angle between the permanent magnets in the first V-shaped permanent magnet grooves is alpha, the included angle between the permanent magnets in the second V-shaped permanent magnet grooves is beta, and the permanent magnets in the first V-shaped permanent magnet grooves and the permanent magnets in the second V-shaped permanent magnet grooves are separated by the aid of an NSGA-II algorithm under the condition that the distance of the magnetic isolation bridge is unchanged. By adjusting the angle between the permanent magnets in the first V-shaped permanent magnet grooves and the second V-shaped permanent magnet grooves, the best matching combination of the small permanent magnet included angle alpha and the large permanent magnet included angle beta is optimized, and the arc-shaped auxiliary grooves are formed in the surface of the rotor iron core, so that the cogging torque of the permanent magnet motor is optimized.

The invention discloses an axial winding complementary type hybrid excitation high-speed magnetic flux reverse motor, and belongs to the technical field of power generation, power transformation or power distribution. The motor comprises a six-slot stator iron core, a four-tooth rotor iron core, a set of annular winding serving as an excitation winding and a set of concentrated winding serving as an armature winding, permanent magnet groups are attached to the inner surface of the tooth part of the stator core, two groups of axial permanent magnets are opposite in polarity, and two groups of circumferential permanent magnets are opposite in polarity; and the rotor iron core is formed by laminating a plurality of rotor iron core sections which have a mechanical angle of 45 degrees in the axial direction. The motor has the magnetic field adjusting capacity and has the advantages of being small in flux linkage, counter electromotive force sine, cogging torque and torque fluctuation, extra rising voltage caused by strong armature reaction during high-speed operation can be reduced through flux weakening, torque during low-speed operation can be improved through flux increasing, and due to the fact that the number of poles is small, loss is small during high-speed and high-frequency operation, and the motor is high in reliability. Compared with other magnetic flux reverse motors, the magnetic flux reverse motor is more suitable for high-speed operation.

The invention relates to a flywheel energy storage motor structure optimization method and device based on an improved hedera helix algorithm. The method comprises the following steps: acquiring upper and lower limits of slot depth, upper and lower limits of slot width and cogging torque of the flywheel energy storage motor; taking a peak-to-peak value calculation formula of the cogging torque as a target function; each individual is set to comprise two dimensions of groove depth and groove width, the fitness of each individual is a value of an objective function, and an initial population is obtained through cubic chaotic mapping in a solution space; the growth rate and the fitness of each individual are calculated under the current iteration times, and the individual with the minimum fitness is selected as the current optimal individual; calculating the temporary position of the corresponding individual, correcting the temporary position by using the adjustment vector to obtain a corrected position, updating according to the corrected position, and calculating the fitness of each individual after the position is updated; and when iteration is ended, selecting the groove depth and groove width corresponding to the individual with the minimum fitness from the individuals after position updating as optimal solutions of the optimization variables. The method can improve the performance of the flywheel energy storage motor.

The invention discloses an outer rotor permanent magnet synchronous motor torque optimization method, which comprises the following steps: 1) design parameter selection: selecting key characteristics of a motor stator slot as design parameters, including slot shoulder height Hs1, tooth length Hs2, chord length Bs0 and slot shoulder width Bs1; 2) finite element model construction: establishing a multi-target finite element model with cogging torque, torque pulsation and average torque as targets; 3) establishing an analytic model: establishing the analytic model of the motor torque by using an energy method and a repetitive unit method, and comparing the analytic model with the finite element model to verify the accuracy of the analytic model; 4) response surface model construction: based on the simulation data of the finite element model, performing finite element analysis by adopting a central composite design CCD, constructing a response surface model, performing sensitivity analysis on design variables, and determining the influence of each variable on an optimization target; and 5) optimization efficiency improvement: determining optimal configuration in a design space by using an adaptive genetic aggregation algorithm AGA, and achieving a multi-objective optimization effect.

The invention relates to the field of motor structure design and optimization, and discloses a cogging torque and torque ripple optimization method for a permanent magnet motor for a vehicle. The method comprises the steps that based on an electromagnetic scheme, a geometric boundary and a term dictionary, a parameterized geometric prototype containing four symmetric semi-arc auxiliary grooves is constructed, and a design variable set structure is generated; converting the structure into a target evaluation interface structure containing a target item and a constraint item; an improved adaptive particle swarm algorithm is combined with finite element rapid check and a new iteration function to carry out optimization solution, and an updated candidate group structure is generated; and finally, optimal parameters are screened through Pareto sorting and robustness recheck, and an engineering configuration structure is generated. According to the method, through systematic parameter modeling, an efficient collaborative optimization algorithm and simulation evaluation, the optimization efficiency and reliability are remarkably improved, the cogging torque and the torque ripple of the motor are effectively reduced, and meanwhile, the process feasibility and the performance robustness of a design scheme are ensured.

The invention discloses a permanent magnet synchronous motor cogging torque suppression method and device based on coordinate analysis, and belongs to the technical field of permanent magnet synchronous motors, and the method comprises the steps: effectively suppressing the cogging torque of a permanent magnet synchronous motor through collaborative optimization of the geometric parameters of stator and rotor auxiliary slots, reducing the torque pulsation, and improving the vibration noise, thereby improving the cogging torque of the permanent magnet synchronous motor. The comprehensive performance of the motor is improved. Wherein the stator auxiliary slots weaken periodic components related to stator tooth slots in air gap magnetic conductance harmonic waves by adjusting slot widths and depths, and excitation of the periodic components to tooth slot torque is reduced; the rotor auxiliary grooves optimize the pole-arc coefficient by adjusting the opening angle, and remanence harmonic waves of the permanent magnets are inhibited from being periodically matched and coupled with the stator tooth grooves. The collaborative design of the two enables the amplitudes and phases of air-gap magnetic conductance harmonic waves and permanent magnet residual magnetic harmonic waves to be mismatched, the amplitude of cogging torque is remarkably reduced, meanwhile, periodic disturbance of an air-gap magnetic field is reduced, the output torque is more stable, and mechanical vibration and noise caused by electromagnetic force fluctuation are synchronously weakened.

The invention provides a permanent magnet synchronous motor and a vehicle. The permanent magnet synchronous motor comprises a stator structure and a rotor structure, the rotor structure is sleeved with the stator structure, the stator structure comprises a stator iron core (1), the rotor structure comprises a rotor iron core (3), the stator iron core (1) comprises stator grooves (2), the stator grooves (2) comprise first stator grooves (21) and second stator grooves (22), and the first stator grooves (21) and the second stator grooves (22) are arranged in one pole. When the d-axis of the rotor structure coincides with the magnetic pole center line of the stator structure, the first stator grooves (21) are located on the two sides of the q-axis of the permanent magnet synchronous motor and are adjacent to the q-axis, the second stator grooves (22) are located between the two first stator grooves (21) on the two sides of the d-axis, the notch width of the first stator grooves (21) is B1, the notch width of the second stator grooves (22) is B0, and B1 is smaller than B0. According to the permanent magnet synchronous motor, the cogging torque of the motor and the torque pulsation of the motor can be reduced, the harmonic content of the motor is reduced, and the noise and vibration of the motor are reduced.

The invention provides a composite groove type stator punching sheet and a motor formed thereof.The stator punching sheet comprises M composite grooves distributed in the circumferential direction of the stator punching sheet, each composite groove comprises a first winding groove and a second winding groove which are distributed along the two sides of the center line of the groove, and the first winding grooves and the second winding grooves are different in structure; the inner side wall of the first winding groove comprises at least one section of arc, and the inner side wall of the second winding groove does not comprise an arc and is only enclosed by straight lines; m is an integer greater than or equal to 3. The first winding slots effectively modulate an air-gap magnetic field by utilizing smooth arc-shaped contours of the first winding slots, so that cogging torque and torque pulsation caused by magnetic conductance change are greatly reduced; the second winding groove is used for enhancing the magnetic circuit capacity and ensuring that the main magnetic flux can pass through efficiently without saturation, so that the harmonic content and the stator iron loss are greatly reduced; the first winding groove and the second winding groove complement each other in the aspects of electromagnetic performance and process advantages and are synergistically enhanced, so that a high-performance and low-cost synergistic effect is realized.

The invention discloses a pumping unit disc type permanent magnet motor multi-objective parameter optimization method, which relates to the technical field of motor design and optimization, and comprises the following steps: pre-establishing a multi-physical field coupling simulation model, constructing a disc type permanent magnet motor electromagnetic and thermal performance simulation model based on Motor-CAD and Maxwell software, and completing no-load, load and thermal performance tests of the motor. According to the method, the multi-physical field coupling simulation model is established in advance, so that comprehensive coupling analysis of electromagnetic and thermal performance of the disc type permanent magnet motor is realized, and high-precision data support is provided for multi-objective optimization; key structure parameters such as air gap length, slot opening width and the like are scientifically selected as optimization objects, maximization of motor efficiency and minimization of cogging torque are taken as core targets, and meanwhile, constraint requirements of output torque, back electromotive force and structure size are strictly adherent to each other, so that the pain point that multiple performances are difficult to consider at the same time in traditional optimization is effectively solved.

The invention discloses a rotor punching sheet and a rotor structure of a low-harmonic permanent magnet motor, and the rotor punching sheet comprises a rotor punching sheet body, each magnetic pole unit is symmetrically provided with a first V-shaped magnetic steel groove and a second V-shaped magnetic steel groove, and the first V-shaped magnetic steel groove is located between a shaft hole and the second V-shaped magnetic steel groove; a first auxiliary groove, a second auxiliary groove and a third auxiliary groove are formed in the outer circle of the rotor, and the auxiliary grooves in the unit magnetic poles are symmetrically distributed about the d-axis center line. The first auxiliary groove is located between the q-axis center line and the first V-shaped magnetic steel groove, the second auxiliary groove is located between the first V-shaped magnetic steel groove and the second V-shaped magnetic steel groove, and the third auxiliary groove is located between the second V-shaped magnetic steel groove and the d-axis center line. Three pairs of auxiliary grooves are formed in the outer circle of the rotor, and by reasonably designing the topological structure of the double-V-shaped rotor and the shapes and the positions of the auxiliary grooves of the rotor, the distribution of an air-gap magnetic field is optimized, the magnetic field harmonic waves of the motor are weakened, the cogging torque and the torque pulsation of the motor are reduced, and the vibration noise of the motor is improved.

The utility model discloses a permanent magnet synchronous motor which comprises a rotor, a stator and a rotating shaft, the rotating shaft is arranged at the circle center of the rotor in a penetrating mode, the rotor is embedded in the stator, the middle section of a tooth portion of the stator is arranged in an arc shape, the two ends of the tooth portion of the stator are arranged in a flat cutting mode, and air gaps of the stator and the rotor are arranged in an uneven mode. The permanent magnet synchronous motor comprises a rotor and a stator, the outer circle of the rotor is of a two-section chamfering structure, permanent magnets of a V-shaped structure are arranged in the rotor, and the permanent magnets are distributed at intervals in the circumferential direction of the rotor, according to the permanent magnet synchronous motor, the pole-arc coefficient and the effective air gap length of the motor are adjusted through the outer circle shape of the rotor and the tooth tip shape of the stator, and therefore the motor efficiency is improved. Therefore, the air gap flux density harmonic amplitude is reduced, and the cogging torque and the torque ripple of the motor are reduced.

The invention discloses a stator assembly, a motor and electrical equipment, the stator assembly comprises a stator yoke part and a plurality of first stator teeth and a plurality of second stator teeth which are alternately arranged on the periphery of the stator yoke part at intervals along the circumferential direction, each first stator tooth comprises a first tooth part and a first tooth crest, and each second stator tooth comprises a second tooth part and a second tooth crest, the minimum tooth width W1 of the first tooth part, the minimum tooth surface width W2 of the first tooth crest, the minimum tooth width W3 of the second tooth part, the minimum tooth surface width W4 of the first tooth crest, the minimum distance L1 between two adjacent first tooth crests and the minimum distance L2 between the adjacent first tooth crest and second tooth crest meet the following conditions: (L1 / L2) * (W1 / W3) * (W2 / W4) is more than 10 and less than 40, W1 is more than W3, and W2 is more than W4; at least one side of the first tooth crest along the circumferential direction is provided with a first groove, and the notch of the first groove is opposite to the stator yoke part. According to the stator assembly provided by the invention, the back electromotive force of the motor can be maximized, and the performance of a torque current line curve is better, so that the output capability and efficiency of the motor are improved, and the cogging torque and the torque pulsation can be reduced.

The utility model discloses a motor stator and a motor, and relates to the technical field of motors, the motor stator comprises a stator tooth module, a stator yoke module and a plurality of winding coils, the stator tooth module comprises a plurality of stator tooth modules which are sequentially connected along the circumferential direction of the motor stator, each stator tooth module comprises at least one stator tooth, and the winding coils are wound around the stator tooth module. Any two adjacent stator teeth are arranged at intervals along the circumferential direction of the motor stator to form stator slots; the stator yoke module comprises a plurality of stator yoke modules which are sequentially connected along the circumferential direction of the motor stator, and the plurality of stator yoke modules jointly surround the periphery of the stator tooth module and seal the openings of all stator slots; the winding coils are correspondingly accommodated in the stator grooves; wherein the stator tooth module and the stator yoke module are spliced into a whole. The utility model aims to effectively avoid the problems of serious air-gap magnetic field distortion, large cogging torque and torque pulsation, large stray loss, high temperature rise and high noise of the open slot of the high-voltage motor caused by cogging effect.

Provided in the present application are a rotor lamination and a forming method therefor, a rotor iron core, a servo motor and a robot. The rotor lamination comprises a lamination body (1), the lamination body (1) having a rotor outer circumference (2); under one pole, the rotor outer circumference (2) of the lamination body (1) is provided with a groove (3) recessed inwards relative to the rotor outer circumference (2) and / or a protrusion (4) protruding outwards relative to the rotor outer circumference (2). According to the rotor lamination of the present application, the stamping precision of the outer contour of the rotor lamination can be improved, allowing a reduction in the cogging torque and torque ripple of the electric motor, and thereby improving the positioning accuracy of the robot.

The utility model discloses an axial magnetic flux motor which comprises a rotor and a stator, the rotor comprises a plurality of magnets which are annularly arranged at intervals, the stator is arranged in the axial direction of the rotor, the stator comprises a stator iron core, the stator iron core comprises a plurality of iron core blocks which are annularly arranged at intervals, and air gaps are formed between the iron core blocks and the magnets. And the air gap is gradually widened from the center of the air gap to the two circumferential sides of the air gap. According to the technical scheme, the air gap between the iron core block and the magnet is designed to be gradually widened in the direction from the center of the iron core block to the two circumferential sides, so that the non-uniform air gap is formed, the back electromotive force waveform of the axial flux motor is improved, the harmonic content is reduced, the efficiency of the axial flux motor is improved, the cogging torque and the torque pulsation are reduced, and the service life of the axial flux motor is prolonged. And the performance is improved.

The present invention provides a single-phase permanent magnet motor and a vacuum cleaner having the same. The single-phase permanent magnet motor includes a first type of stator teeth; a second type of stator teeth, the first type of stator teeth and the second type of stator teeth are arranged to form an accommodating cavity for accommodating a rotor portion; a gradient air gap thickness is formed between one of the first type of stator teeth and the second type of stator teeth and the rotor portion, and a uniform air gap thickness is formed between the other of the first type of stator teeth and the second type of stator teeth and the rotor portion. By providing two types of stator tooth structures and forming different air gap structures between the two types of stator teeth and the rotor portion, the electromagnetic torque and the cogging torque of the motor are staggered, thereby solving the problem of the starting dead point of the single-phase motor. Compared with a simple asymmetric tooth structure, this structure can greatly improve the starting ability of the motor, reduce the starting current of the motor, and eliminate the problem of the dead point of the motor starting in the prior art.

The application discloses a motor and a household appliance, and belongs to the technical field of motors. The motor comprises a stator assembly and a rotor assembly. The rotor assembly comprises a rotor core and a plurality of magnets. The rotor core is provided with a plurality of magnet grooves. Rotor punching sheets are stacked along the axial direction of the rotor core to form at least one first core section and at least one second core section. Along the circumferential direction of the rotor core, each first core section comprises a plurality of first sector blocks arranged at intervals, each second core section comprises a plurality of second sector blocks arranged at intervals, each core unit comprises a plurality of first sector blocks and a plurality of second sector blocks arranged in layers, a first outer magnetic bridge is protruded on the first side of the outer circumferential edge of each first sector block, a second outer magnetic bridge is protruded on the second side of the outer circumferential edge of each second sector block, the first outer magnetic bridge and the second outer magnetic bridge are arranged at different positions along the axial direction of the rotor core, and the effect of a segmented skew pole of the rotor is formed. The above structure can reduce the cogging torque and torque fluctuation of the motor.

The purpose of the present invention is to reduce the cogging torque of an electric motor. The motor is provided with: a stator (20) formed by welding a plurality of split iron cores (21); and a rotor disposed so as to face the stator (20), the rotor having a first region (R1) as a region from an axial end of the stator (20) to a terminal end of a continuous welded portion (22) closest to the axial end, and a second region (R2) as a region other than the first region (R1) and including an axial center portion of the stator (20). In at least one of the plurality of joining parts (J) between the plurality of divided iron cores (21), the proportion of the welded parts in the second region (R2) is smaller than the proportion of the welded parts (22) in the first region (R1).

The application provides a low-noise motor optimization method based on multi-parameter variable fusion, and the specific process is as follows: taking motor back electromotive force variation and minimum slot torque as an optimization objective function; taking motor rotor magnetic pole circular arc wrap angle as an optimization variable, and multiple iterations of the magnetic pole circular arc wrap angle are carried out in a set range, the magnetic pole circular arc wrap angle corresponding to the minimum objective function is taken as an optimal parameter of the motor, and low-noise motor optimization is realized; the magnetic pole circular arc wrap angle is proportional to the magnetic pole circular arc length. In the method, the magnetic pole circular arc wrap angle is taken as an optimization object, and the optimization design can be quickly and effectively completed, and the low-noise motor for vehicles can be developed.

The application relates to a pole shoe mounting and positioning structure of a motor, which comprises a stator core, the stator core comprises a plurality of stator teeth, a coil is sleeved on the stator teeth, a pole shoe is mounted at the end of the stator teeth, and a plurality of insulating baffle plates are inserted into the gap between the inner circumferential surface of the coil and the side surface of the stator teeth, the two side surfaces of each stator tooth are provided with the insulating baffle plates, and the insulating baffle plates are in contact with the pole shoes; the insulating baffle plate comprises an insertion part and a baffle part, the width of the baffle part is larger than that of the insertion part, a plurality of guide inclined surfaces are formed on the insertion part, and the baffle part presses the pole shoe after the insertion of the insulating baffle plate is completed. Compared with the prior art, the opening of the stator slot is reduced in the mounting of the pole shoe, torque fluctuation is reduced, tooth slot torque is reduced, radial force fluctuation is reduced, and the motor NVH performance is improved; the simple and low-cost insulating bamboo stick can make the coil winding firm, fill the gap, increase the insulation reliability, and prevent the pole shoe from slipping due to the motor vibration.

The invention discloses a stator and rotor punching sheet for a permanent magnet synchronous motor and a motor, and relates to the technical field of permanent magnet synchronous motors, the stator and rotor punching sheet comprises a stator and a rotor, the rotor is formed by splicing a plurality of rotor punching sheets, and the rotor comprises a second rotor punching sheet forming a constant air gap with the stator, a first rotor punching sheet and a third rotor punching sheet, and the first rotor punching sheet and the third rotor punching sheet form a non-uniform air gap with the stator. The rotor is a three-section type rotor, the circular truncated cone-shaped rotors are symmetrically arranged on the two sides of the middle cylindrical rotor, three groups of air gaps are formed on the inner side of the stator, and cogging torque and torque pulsation can be reduced through mutual cooperation of the circular truncated cone-shaped rotors and the inner side of the stator. The magnetic steel grooves of the rotor are respectively V-shaped and double-V-shaped, so that the harmonic magnetic field content of the rotor can be improved, the noise can be reduced, the comprehensive cost can be reduced by the V-shaped magnetic steel grooves, and the power density can be improved by the double-V-shaped magnetic steel grooves.

To provide a silicon steel sheet for a motor of a range hood that improves the problems of the existing motor winding structure, such as high production costs, a tendency to generate vibration noise, and relatively poor magnetic flux stability. [Solution] The range hood motor silicon steel plate (10) includes an outer ring (11), a plurality of first teeth (12), and a plurality of second teeth (13). The plurality of first teeth protrude radially from at least a portion of the inner peripheral surface of the outer ring, and the plurality of second teeth protrude radially from another portion of the inner peripheral surface of the outer ring. The inner peripheral surface of the outer ring includes at least one spaced apart tooth arrangement main edge (111) and at least one tooth arrangement sub-edge (112). By controlling the angles of the main angle (S1) formed by the tooth arrangement main edge and the sub-angle (S2) formed by the tooth arrangement sub-edge, as well as by controlling the dimensions and geometric structure of the first and second teeth, it is possible to significantly reduce the generation of cogging torque and abnormal noise, while also effectively reducing the amount of conductive coil used, thereby lowering production costs and achieving a lighter motor.

This invention provides an electric motor, an electric power steering system, and a vehicle. The motor includes a stator core, a rotor core, and an air gap. The rotor core is located inside the stator core, and the air gap is located between the rotor core and the stator core. The axial height Ls of the stator core, the outer diameter Dso of the stator core, the stator split ratio k of the stator core, the axial height Lr of the rotor core, and the width lg of the air gap satisfy the following: This application optimizes the dimensional relationship between the stator core, the rotor core, and the air gap between them. Without increasing the number of components, it effectively solves the problem of motor performance degradation caused by end magnetic leakage, thereby reducing cogging torque, suppressing torque pulsation, increasing the average torque of the motor, and improving motor vibration and noise. While ensuring motor performance, it can minimize motor weight and reduce production costs.

The invention provides a rotor structure and a motor, magnet grooves comprise two first magnet grooves and two second magnet grooves which are communicated with each other, the two second magnet grooves are located between the two first magnet grooves, and two sides of a D shaft of a magnetic pole are respectively provided with one first magnet groove and one second magnet groove; a first V-shaped groove with an opening deviating from the central point of the rotor core is formed between the two second magnet grooves, and a second V-shaped groove with an opening facing the central point of the rotor core is formed between the adjacent first magnet groove and the second magnet groove; wherein a plurality of magnetic barrier holes are formed between the first V-shaped grooves and the outer peripheral wall of the rotor core, and a plurality of auxiliary grooves are formed in the outer peripheral wall, corresponding to the second V-shaped grooves, of the rotor core; while the high salient pole ratio is ensured, the cogging torque is reduced, magnetic flux leakage and higher harmonics are inhibited, and meanwhile, the power density and efficiency of the motor are not influenced.

This invention provides a method for suppressing cogging torque in a permanent magnet synchronous motor based on FxLMS, ​​comprising the following steps: The unfiltered torque demand waveform output from the PI speed loop is obtained; the torque demand is processed by a static low-pass second-order Butterworth filter to obtain a filtered torque demand waveform; the torque demand is simultaneously processed by a static high-pass second-order Butterworth filter to obtain a waveform containing only the cogging torque component, forming a noise reference signal; this signal is input into a modified FxLMS filter to obtain an anti-noise signal; this signal is input to a summing module and superimposed with the filtered torque demand waveform to generate a combined torque demand for cogging torque cancellation; the combined torque demand is input to a gain module to generate a q-axis current reference value; this reference value is input to the PI current loop; the combined torque demand is simultaneously fed back to the PI speed loop and combined with the actual speed error of the motor to generate a new torque demand value; the system then returns to the beginning, forming a closed-loop operation.

The present invention relates to a control method and control apparatus for a permanent magnet synchronous motor. The control method comprises: a compensation measurement step, which comprises: by means of an experimental test performed in advance, measuring and calculating a plurality of cogging torques of a rotor at a plurality of rotation positions within a rotation cycle, and generating a lookup table that represents mapping relationships between the plurality of rotation positions and the corresponding plurality of cogging torques; and a compensation application step, which comprises when a permanent magnet synchronous motor is operating, on the basis of the lookup table generated in the compensation measurement step, determining a cogging torque corresponding to the current rotation position of the rotor, and applying a corresponding compensation signal to a control circuit of the permanent magnet synchronous motor. The control method and control apparatus in the present invention can improve the effect of cogging torque compensation.

The utility model provides a kind of low vibration, low noise stepping motor, including stator lamination and rotor lamination, the inside of stator lamination and rotor lamination is provided with the small tooth of improving electromagnetic coupling efficiency, the tooth slot ratio, tooth width, tooth shape and the included angle of adjacent small tooth of small tooth are all optimized improvement, the inside of stator lamination and rotor lamination is all increased and is set, it is related to the technical field of stepping motor.The utility model is designed by the tooth slot ratio, tooth width, tooth shape, the included angle of adjacent small tooth, the riveting point of stator lamination eight big poles on small tooth, the tooth slot ratio, tooth width, tooth shape, the riveting point of rotor lamination on small tooth, design optimization is carried out, reduce high harmonic, reduce tooth slot torque, make motor low-speed operation stability better, vibration and noise are smaller.

A motor cogging management system for an electrified vehicle includes a set of sensors configured to monitor a set of parameters for the electrified vehicle, wherein the set of parameters includes at least a speed of the electrified vehicle and a control system configured to determine whether cogging torque management is required for a first electric motor of the electrified vehicle based on the set of parameters, determine a maximum cogging management torque based on the set of parameters, determine a sign for the cogging torque management based on the set of parameters, and perform the cogging torque management by commanding additional torque at the first electric motor based on the determined maximum cogging management torque and the determined sign.

The invention relates to a multi-pole rotor, a motor and an automobile, the multi-pole rotor rotates along the central axis of the multi-pole rotor, and the multi-pole rotor comprises a plurality of radial magnets and a plurality of tangential magnets. The radial magnets are distributed in the circumferential direction of the central axis, and the magnetizing direction of the radial magnets is in the radial direction of the central axis; each tangential magnet is arranged between two adjacent radial magnets, and the magnetizing direction of the tangential magnets is along the tangential direction of the central axis; the angles occupied by the radial magnets and the tangential magnets are different in the circumferential direction of the central axis. The radial magnets and the tangential magnets with different magnetizing directions are adopted, the magnets with different magnetizing directions jointly form a complete magnetic circuit, the sizes of the radial magnets and the tangential magnets can be designed according to the direction and strength of a magnetic field, the higher harmonic content and the cogging torque are reduced, the magnetic field of the motor is more ideal, the motor runs more stably, and the service life of the motor is prolonged. Motor loss is reduced, and motor efficiency is improved.

The invention provides a joint optimization method for geometric parameters of an outer rotor brushless direct current motor. According to the joint optimization method, average torque maximization, torque pulsation minimization and cogging torque minimization are taken as optimization targets; the method comprises the following steps: firstly, constructing a motor performance meta-model based on AMOP sampling and a moving least square-isotropic Kriging method, and establishing comprehensive sensitivity through Pearson correlation to distinguish primary sensitive and secondary sensitive variables; and then, a q-ROFS-TOPSIS method is introduced, so that a unified closeness degree evaluation index can be obtained. The optimization process adopts a two-layer staged optimization strategy: in the first stage, sub-sensitive variables are dominated, main sensitive is allowed to perform fine tuning, the relevance between main and sub parameters is emphasized, and optimization is performed through a particle swarm optimization algorithm; and in the second stage, the main sensitive variable is adjusted on the basis of the sub-sensitive optimization, and optimization is carried out through an evolutionary algorithm. According to the method, the optimal motor geometric parameter combination with high average torque, low torque ripple and low cogging torque can be obtained under the conditions of incomplete samples and multiple working conditions.