406 results about "Cogging torque" patented technology

Disclosed is a low-precision incremental encoder-based method for ultra-low speed control of a servo system. According to the present invention, a fast speed observer in an ultra-low-speed working state is achieved, only a sampling speed and load torque in an M / T method need to be observed, and position information of an electric motor does not need to be observed, such that the structure of the observer is simplified, and calculation is simple and fast; moreover, the influence of a friction force and cogging torque on a speed change is considered, such that the speed observation precision is further improved. The fast speed observer can reduce hysteresis and measurement dead zones, such that the speed response and the speed control precision in a low-speed working state are greatly improved, the problem in a traditional observer of a large position deviation caused by nonlinear factors such as an external load is avoided, improving the stability and robustness of the system. According to the present invention, the processing of sampling measurement time at a medium-high speed and the processing of switching the observer at a low speed in the M / T method can optimize the speed measurement precision at both the medium-high speed and the ultra-low speed, and can better satisfy the requirements of apparatuses such as a radar on rotating speed control.

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 data-driven linear electric joint cogging torque compensation and evaluation method for a humanoid robot, and belongs to the technical field of control of linear electric joints of humanoid robots. The problems that an existing humanoid robot linear joint cogging torque compensation method is long in consumed time, difficult to operate and poor in precision are solved. According to the invention, the motor rotates a circle in the forward direction and the reverse direction respectively, the forward current and the reverse current are sampled, and the position of the motor and the corresponding current at the position are recorded at the same time; determining the number of sampling points in the sampling time according to the rotating speed of the motor, calculating the number of position points of the motor, obtaining a mapping relation between forward and reverse currents and the position of the motor, and representing the position points of the motor by using the forward and reverse currents; based on the relation between the cogging torque and the forward current and the reverse current, the mapping relation between the position, represented by the forward current and the reverse current, of the motor and the corresponding cogging torque is obtained, and then iterative compensation is conducted on the joint cogging torque based on the position, represented by the forward current and the reverse current, of the motor and the corresponding cogging torque mapping relation.

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 discloses a permanent magnet brushless direct current motor and a parameter optimization method thereof. A rotor adopts a regular hexagon structure, and permanent magnets are alternately embedded into the rotor. Seven parameters such as the maximum thickness of a permanent magnet, a pole-arc coefficient and the width of a stator notch are selected for optimization, air gap flux density, no-load back electromotive force and no-load cogging torque are taken as optimization targets, a response surface model of a multi-objective function is constructed, parameter weights of the multi-objective function are determined in combination with a CRITIC weight analysis method, the motor parameters are optimized by adopting an improved MOEA / D algorithm, and the optimal parameters of the multi-objective function are obtained. And carrying out crossover variation on the population by directional variation guided by electromagnetic characteristics, and designing a weight vector optimization Chebyshev aggregation method to find an optimal iteration population. According to the weight in the Chebyshev aggregation function designed by the invention, the problems that the traditional Chebyshev aggregation method is not smooth enough for the continuous MOP problem and the obtained solution is not uniform are solved, and the distribution uniformity of the Pareto solution set is optimized. The method has obvious advantages in the aspects of convergence speed, solution set distribution and engineering feasibility.

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.

To provide a rotor and a motor that can reduce cogging torque.SOLUTION: A rotor RT includes: ten magnet parts MG; and a rotor core. The ten magnet parts MG are arranged in a circumferential direction around a central axis extending in a vertical direction. The rotor core includes a plurality of magnetic pole parts 61. Each magnet part MG is housed in a magnet arrangement part SP1. The magnet arrangement part SP1 is provided between adjacent ones of the magnetic pole parts 61. A radially outer surface 62 of the magnetic pole part 61 has: an arc part 622; and a peripheral part 624. The arc part 622 has a radius of curvature about the central axis. The peripheral part 624 extends from a circumferential end of the arc part 622. The peripheral part 624 is an arc having a radius of curvature different from that of the arc part 622 or a straight line. The width of the arc part 622 is A. The width of the peripheral part 624 is B. A ratio represented by A / (A+B×2) is 0.64 or more and 0.8 or less. The peripheral part covers a surface of a corner part of a magnet part for which a direction of the central axis is a normal direction.SELECTED DRAWING: Figure 2B

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 built-in self-starting permanent magnet synchronous motor magnetic field analytical algorithm based on an equivalent magnetic circuit and an analytical method, and relates to the field of motor design. A self-starting permanent magnet synchronous motor has a starting cage and rotor surface slotting, so that magnetic field distribution is complex, a magnetic field analysis model is difficult to establish in a polar coordinate system, and meanwhile, rotor surface slotting causes air-gap magnetic field distortion, so that a traditional path calculation method is insufficient in precision and low in calculation precision. Although the numerical simulation result is accurate, the consumed time is long and the efficiency is low in the optimization design process of the motor; therefore, the invention provides a new thought for magnetic field analysis research of the self-starting permanent magnet synchronous motor, an equivalent magnetic circuit method is adopted to model a rotor structure, an analysis method is adopted to model an air gap domain and a stator structure, coupling is realized through a magnetic field continuity relation of a rotor and an air gap interface, and a conformal transformation method is combined to obtain the self-starting permanent magnet synchronous motor. A magnetic field analysis calculation model considering rotor slotting is established, efficient and accurate calculation of the magnetic field of the self-starting permanent magnet synchronous motor is achieved, and the design, research and development period of the motor can be greatly shortened; according to the research thought, the flux density, harmonic analysis and cogging torque of the air gap domain can be obtained, the accuracy of the magnetic field analytical model is verified through comparison with a finite element method, and an analytical method is provided for subsequent electromagnetic design and structure optimization.

The utility model provides a rotor structure and a motor, the rotor structure comprises a rotor core, the rotor core is provided with a plurality of filling grooves, and the filling grooves are uniformly arranged along the circumferential direction of the rotor core; one filling groove comprises two groups of non-independent filling grooves, the two groups of non-independent filling grooves are symmetrically arranged about the D axis, the two groups of non-independent filling grooves are arranged in a V shape, and the openings of the filling grooves face the outer circumferential edge of the rotor iron core; the group of non-independent filling grooves comprises a first magnetic steel groove, a second magnetic steel groove and a third magnetic steel groove which are communicated in sequence, the first magnetic steel groove is close to the center of the rotor core relative to the second magnetic steel groove, the third magnetic steel groove is close to the outer circumferential edge of the rotor core, and the first magnetic steel groove and the second magnetic steel groove are arranged in a staggered manner. According to the utility model, the technical problem that the cogging torque of the motor is increased because the left and right magnetic steel slot structures of the rotor structure are asymmetric under the same magnetic pole in the prior art can be solved.

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 invention discloses a range extender generator for a 30000-turn electric aircraft, which adopts a mode that an inner rotor has 18 slots, 10 poles and five sections of rotor iron core skewed slot magnetic steel is radially inserted, and has the excellent performances of symmetrical magnetomotive force waveform, high winding coefficient, low torque pulsation and cogging torque and no end ring current. The motor adopts a centralized winding, winding oil cooling and shell water cooling mode, and is suitable for a generator for a range extender of an electric aircraft.

The utility model relates to the technical field of motors, in particular to a novel brushless direct current motor, which comprises a rotor assembly (100), a stator assembly (200), a first end cover (300) and a second end cover (400), the rotor assembly (100) comprises a rotor (101), a rotor shaft sleeve (102) and rotor magnetic steel (103), and the rotor shaft sleeve (102) is made of aluminum materials; the second end cover (400) is provided with a Hall plate (500), and the Hall plate (500) is provided with three surface-mounted Hall elements (501) used for sensing the rotor magnetic steel (103). Due to the adoption of the structural design, the rotor shaft sleeve of the rotor assembly is made of an aluminum material, so that the distribution of magnetic lines of air gaps in the motor is changed, and the problems of large cogging torque and noise of the motor are effectively solved; a Hall element on the Hall plate directly induces motor rotor magnetic steel in a patch mode, so that the reliability of the motor is greatly improved, the structure is simplified, and assembly is facilitated.

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 present invention may provide a motor including a rotor and a stator disposed to correspond to the rotor, wherein the rotor includes a rotor core and a magnet disposed on the rotor core, the rotor core includes a first region in which the magnet is disposed, the first region of the rotor core includes two grooves, one of the two grooves is disposed at a position corresponding to one end region of the magnet, and the other one of the two grooves is disposed at a position corresponding to the other end region of the magnet.

The invention relates to the technical field of motor rotor punching sheets, in particular to a motor rotor punching sheet structure and a rotor, which comprises a rotor punching sheet, eight groups of first-layer V-shaped magnetic steel grooves are arranged on the rotor punching sheet in an annular array, and each first-layer V-shaped magnetic steel groove is composed of two linear groove bodies. The two ends of each group of first-layer V-shaped magnetic steel grooves are provided with first-layer magnetic steel groove air magnetic isolation grooves close to the outer diameter end of the rotor and first-layer magnetic steel groove air magnetic isolation grooves close to the inner diameter end of the rotor respectively, the bottom end of each group of first-layer V-shaped magnetic steel grooves is provided with first-layer magnetic steel groove magnetic bridges, and second-layer magnetic steel is placed in the second-layer V-shaped magnetic steel grooves. A plurality of V-shaped magnetic steel groove magnetic bridges are arranged on the outer side of the rotor punching sheet in an annular array mode, through the design of the double-layer V-shaped magnetic steel groove rotor punching sheet structure, a magnetic circuit is optimized, leakage magnetic flux is reduced, reluctance torque is increased, cogging torque is reduced, the torque and power density of the motor are improved, the leakage magnetic flux of each magnetic pole is weakened, and the main magnetic flux of the motor is enhanced.

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.

To effectively reduce the cogging torque of axial gap motors.SOLUTION: A first motor 101 and a second motor 201 comprise: rotors 120, 220 rotating around the rotation axis AX3; rotors 120, 220 and stators 110, 210 opposing in the direction of the rotation axis AX3; a back yoke section 303 provided in rotors 120, 220; and a plurality of magnets 305 arranged along the circumferential direction around the rotation axis AX3 in the back yoke section 303. The plurality of magnets 305 comprise: a plurality of first magnets 307 arranged at equal angular intervals in the circumferential direction; and a plurality of second magnets 309 arranged one by one between the plurality of first magnets 307 and displaced by a predetermined shift angle θ1 from the center angle of two circumferentially adjacent first magnets 307.SELECTED DRAWING: Figure 7