14results about How to "Reduce torque ripple" patented technology

This invention belongs to the technical field of motor control and discloses a model predictive control method and system for effectively suppressing the second harmonic of a permanent magnet synchronous motor. The method includes the following steps: obtaining the three-phase input current of the permanent magnet synchronous motor at the current moment, converting the three-phase input current into a sum-i current in a coordinate system; extracting the two orthogonal components of the second harmonic at the current moment from the transfer function of the current input to a second-order generalized integrator; calculating the second harmonic component at the next moment using the two orthogonal components of the second harmonic at the current moment; compensating the fundamental current reference command at the next moment using the second harmonic component at the next moment, obtaining the compensated fundamental current reference command at the next moment, thus achieving the suppression of the second harmonic current at the next moment. This invention solves the problem of not suppressing the second harmonic in the control of permanent magnet synchronous motors.

The utility model relates to a kind of motor rotor structure for realizing rotor flux better sinusoidal distribution, belong to motor technical field, including protective shell, the protective shell is located in rotor, the rotor and protective shell are equipped with stator, the rotor is equipped with magnetic separation slot and magnetic filling slot, the magnetic filling slot is inserted and embedded permanent-magnetic strip, the permanent-magnetic strip includes permanent magnet I, permanent magnet II and permanent magnet III. Permanent magnet I and permanent magnet II, permanent magnet III superposition realizes rotor flux better sinusoidal distribution. Permanent magnet I, permanent magnet II, permanent magnet III and magnetic separation slot jointly form cross-axis magnetic circuit, due to the formation of reluctance torque superposition, thereby increase torque. By optimizing rotor magnetic pole shape, permanent magnet arrangement and auxiliary structure are realized, to reduce harmonic content, improve torque stability. Realize the good sinusoidal distribution of rotor flux, low motor torque ripple and slot effect, to improve the stability of motor operation, efficiency and control accuracy.

This invention relates to the field of electric motors, and more particularly to an electric motor rotor. The electric motor rotor includes: a trapezoidal slot formed on the outer circumferential surface of the motor rotor, the trapezoidal slot having a base edge; a magnet slot, the axis of symmetry of the magnet slot passing through the center of the inner diameter of the motor rotor, the trapezoidal slot being formed on at least one side of the axis of symmetry of the magnet slot, the magnet slot having a first side line; and a magnetic stabilizing hole formed between the outer circumferential surface of the motor rotor and the magnet slot, the longitudinal axis of the magnetic stabilizing hole being perpendicular to the first side line, the magnetic stabilizing hole and the trapezoidal slot being on the same side of the axis of symmetry of the magnet slot, the axis of symmetry of the trapezoidal slot passing through the center of the inner diameter of the motor rotor, an angle α1 between the longitudinal axis of the magnetic stabilizing hole and the axis of symmetry of the trapezoidal slot, and an angle α2 between the longitudinal axis of the magnetic stabilizing hole and the axis of symmetry of the magnet slot, α1 and α2 satisfying 0.701≤(α1-α2) / α1≤0.958. This invention also relates to an electric motor. This invention can effectively reduce the no-load back EMF harmonics of the motor, improving motor efficiency and operational smoothness.

The application provides a rotor core and a motor with the same. The rotor core is formed with a plurality of magnetic poles which are arranged at intervals along the circumference of the rotor core. The outer periphery of the cross section of each magnetic pole comprises a plurality of arc lines and a plurality of straight lines, and the plurality of arc lines and the plurality of straight lines are arranged alternately. The air gap magnetic field between the stator core and the rotor core is optimized, the torque ripple is reduced, the motor demagnetization resistance and the motor efficiency are improved. The stator tooth is opposite to the magnetic pole and comprises a tooth body and a tooth shoe. The tooth shoe comprises two tooth shoes which are arranged at the two radial sides of the tooth body respectively. The tooth body corresponds to the first arc line, and the tooth shoe corresponds to the straight line. The magnetic field in the region between the tooth body and the first arc line is the strongest, the magnetic field in the region between the stator slot and the second arc line is the weakest, and the magnetic field in the region between the tooth shoe and the straight line is in the middle. The position and size of the straight line can be adjusted to adjust the magnetic field in the region. The motor iron loss is greatly reduced, the magnetic steel utilization rate is improved, and the motor harmonic loss is reduced.

The utility model belongs to motor manufacturing technical field especially relates to a rotor structure and motor, and the rotor structure includes rotor core, and the equidistribution of multiple magnetic poles has along its circumference, and each magnetic pole is provided with at least two layers of magnetic steel slot group, and each layer of magnetic steel slot group is C type structure, and each layer of magnetic steel slot group includes two separate magnetic steel slots about direct axis symmetry distribution, and the both ends of each magnetic steel slot are closed, magnetic steel is provided with multiple sections in each magnetic steel slot. The utility model is favorable for improving the magnetic field magnetic circuit of motor, reduces the harmonic distortion rate, thereby improves electromagnetic excitation, reduces motor torque ripple, realizes better motor NVH performance.

This application relates to the field of motor control technology and provides a method, device, and medium for positionless control of an air conditioning compressor. The method includes: acquiring the three-phase current of a permanent magnet synchronous motor in the air conditioning compressor and transforming it to an α-β coordinate system to obtain α-axis current components and β-axis current components; inputting the α-axis current components, β-axis current components, and the first α-axis control voltage and the first β-axis control voltage of the previous cycle to a back EMF observer based on an extended state observer to determine the rotor angle of the permanent magnet synchronous motor; determining the second α-axis control voltage and the second β-axis control voltage based on the α-axis current components, β-axis current components, and rotor angle; determining the three-phase duty cycle based on the second α-axis control voltage and the second β-axis control voltage; and driving the permanent magnet synchronous motor to run by controlling an IGBT inverter, thereby improving the robustness and position estimation accuracy of the positionless control of the air conditioning compressor.

The present application relates to the field of fault-tolerant control of dual three-phase PMSM driving system, and particularly relates to a dual three-phase PMSM open-phase fault-tolerant method for minimizing voltage modulation error, comprising: estimating the phase voltage of the fault phase in the fault winding; estimating the phase voltage of the remaining two phases in the fault winding where open-circuit fault occurs; obtaining the voltage modulation error vector of the fault winding; minimizing the voltage modulation error vector of the fault winding to complete open-phase fault-tolerant control. The present application suppresses the deviation of the "reference-actual" combined voltage vector from the source of the modulation layer, thereby significantly reducing torque ripple, while avoiding parameter reorganization and structural modification of the existing controller, facilitating plug-and-play landing in the existing system. In the one-phase open-phase working condition, the torque ripple amplitude (current amplitude) can be reduced by about 50%, the torque ripple standard deviation can be reduced by about 48.7%, the speed loop output is smooth, and the vibration and noise risk is reduced.

This invention provides a rotor and a motor. The rotor (10) has multiple permanent magnet slots (11). Any two adjacent permanent magnet slots (11) are symmetrical about a second center line (2). The outer contour of the rotor (10) between any two adjacent second center lines (2) is symmetrical about a first center line (1), and includes: a first arc segment (101) located in the middle, two second arc segments (102) extending outward from both ends of the first arc segment (101), two transition segments (103) extending outward from the two second arc segments (102), and two third arc segments (104) extending outward from the two transition segments (103); the center and radius of the second arc segments (102) are different from those of the first arc segment (101). The rotor of this invention reduces torque pulsation and improves motor efficiency without increasing manufacturing difficulty and cost.

This utility model provides a rotor hook-slot structure for a DC motor, including rotor hooks and rotor slots, both located on the outer circumference of the rotor and evenly arranged in a ring on the outer circumference. The rotor hooks are provided in numbers of 12, and the rotor slots are provided in numbers of 18. A wire group extends outward from the rotor hooks and winds around the rotor slots. This rotor hook-slot structure for a DC motor, by increasing the number of rotor slots to 18 (no longer corresponding to a single slot), reduces the current density in a single slot, thereby reducing the impact of armature current on the main magnetic field, helping to reduce magnetic field inhomogeneity, thus reducing sparks during electrolysis and improving commutation performance.

The application provides a motor rotor, a self-starting synchronous reluctance motor, a compressor and a motor rotor. The motor rotor has a slit slot, a second filling slot and a first filling slot on a first rotor lamination. An outer magnetic barrier layer includes the first filling slot, and an inner magnetic barrier layer includes the slit slot and the second filling slot at both ends of the slit slot. Between the second filling slot and the slit slot in the same layer of the inner magnetic barrier layer, there is a separation rib. A side of the separation rib close to an outer circle of the rotor has a center point in an axial plane. The distance between two center points corresponding to two separation ribs in any two adjacent layers of magnetic barrier layers along a d-axis direction is L. The maximum distance between the filling slots in the two adjacent layers of magnetic barrier layers along a q-axis direction is W, and 0<=L<2W. According to the application, the saturation degree of the magnetic conduction channel between the filling slots can be reduced, the motor harmonics can be reduced, the torque ripple can be reduced, the harmonic loss can be reduced, the motor efficiency and the operation stability can be improved.

This utility model discloses a rotor structure for achieving skewed magnetic poles. It employs a segmented skewed rotor magnetic pole structure, comprising several segmented magnetic pole modules and a circular magnetic yoke with grooves. Each magnetic pole module has at least one magnet embedded in it and several through holes for axial and radial positioning and fixing. The inner circle of each magnetic pole module is fitted with the magnetic yoke by several protrusions distributed on both sides, with equal spacing between the protrusions on each side. Furthermore, the position of each magnetic pole module within the segmented skewed pole is determined by the distribution of its protrusions, and it is inserted into the grooves of the magnetic yoke in segments according to a preset skew angle to form a continuous skewed magnetic pole with a preset angle. This utility model can be used in conjunction with a straight stator slot design to improve stator winding efficiency and reduce stator manufacturing costs. The rotor does not increase costs compared to the original non-skewed pole design and is beneficial for engineering implementation. It can effectively weaken specific harmonics, thereby reducing cogging torque and torque pulsation. The axial force problem can be eliminated by designing different numbers of axial magnetic poles.

The utility model discloses a kind of motor, compressor and refrigeration equipment, it is related to motor technical field, wherein, the motor includes stator and rotor, rotor is provided with magnetic steel slot group along circumference, it is equipped with magnet group, each magnet group includes intermediate magnet and the two side magnets of setting in the two sides of intermediate magnet;Two side magnets are mirror symmetry about the magnetic pole center line of the magnetic steel slot group;Two notches are set to each magnetic steel slot group in the radial outer edge of rotor, the included angle α between side magnet and intermediate magnet;The included angle of notch edge and the magnetic pole center line of the magnetic steel slot group is β, the minimum spacing between two notches is X;The length of intermediate magnet along the direction perpendicular to magnetic pole center line is L, satisfy relationship: 0.7≤(α-90°) / β≤1,1.6≤X / L≤2.3, wherein, α>90°.The technical scheme provided by the utility model aims at improving the torque ripple and cogging torque of permanent magnet motor, improving motor efficiency, and then solving the problem of high vibration noise and life attenuation of compressor.

The application relates to the field of vehicle transmission technology and discloses a non-integer multiple magnetic pole proportion and wedge-shaped magnet magnetic force circulating hub system which comprises a bearing seat, a hub assembly, a wheel rim assembly, a first bearing group and a second bearing group. The bearing seat is fixedly connected with a vehicle suspension or a steering knuckle. The hub assembly is rotationally connected between the first bearing group and the bearing seat, the wheel rim assembly is rotationally connected between the second bearing group and the bearing seat, and the wheel rim assembly is coaxially arranged with the hub assembly. A first permanent magnet array is arranged on the hub assembly, and a second permanent magnet array is arranged on the wheel rim assembly. The first permanent magnet array and the second permanent magnet array are arranged between the hub assembly and the wheel rim assembly to form a magnetic field coupling, non-contact power transmission is realized, contact wear and lubrication dependence in traditional mechanical transmission are avoided, transmission efficiency is improved, and the service life of the system is prolonged.

The application discloses a kind of permanent magnet synchronous motor double vector model predicted current control methods considering dead zone, it is related to motor drive control technical field, comprising the following steps: S1, establish PMSM discrete prediction model and sampling: derivation current prediction equation;S2, based on the classification strategy of cost function and torque current: voltage vector is divided into overshoot vector group and under shock vector group;S3, double vector screening strategy based on classification strategy: screening out optimal double vector candidate combination;S4, dead zone determination and beatless time synthesis: output final switch control pulse.The application adopts the above-mentioned permanent magnet synchronous motor double vector model predicted current control method considering dead zone, reduces the current distortion caused by dead zone effect, solves the local optimal problem in traditional strategy, and greatly reduces the calculation burden, provides a kind of efficient control scheme with high dynamic response, global steady-state accuracy and low harmonic characteristic for ship PMSM propulsion system.