35results about How to "Reduced risk of irreversible demagnetization" patented technology

The invention discloses an application method of mixed permanent magnets in a flux-switching permanent magnet motor, and relates to stator-core motors with permanent magnets. Rare-earth permanent magnets with high magnetic energy products are mounted at yoke positions of a stator module of the flux-switching permanent magnet motor. Ferrite permanent magnets with low magnetic energy products are mounted at tooth positions close to the motor stator module. The rare-earth permanent magnets with the high magnetic energy products and the ferrite permanent magnets with the low magnetic energy products are connected to be integrated into the mixed permanent magnets. The mixed permanent magnets with clockwise magnetization directions are mounted on one side of the motor stator module. The mixed permanent magnets with anticlockwise magnetization directions are mounted on the other side of the motor stator module. The mixed permanent magnets with the clockwise magnetization directions and the mixed permanent magnets with the anticlockwise magnetization directions are alternately mounted on two sides of the motor stator module. The defects of ultrahigh cost of existing flux-switching permanent magnet motors, serious magnetic saturation of teeth, reduction of motor torque density and large cogging torque are overcome.

The invention relates to a rotor of a high-quality and high-speed built-in permanent magnet motor and a magnetic steel structural parameter determining method thereof. In the invention, the whole section magnetic steel of each electrode of the rotor of a conventional built-in permanent magnet motor is divided into multiple sections of magnetic steel which have the same polarity and different widths; the multiple sections of the magnetic steel are respectively arranged in a rotor core; and reinforcing ribs with the function of magnetic isolation are arranged among the multiple sections of the magnetic steel. By reasonably modulating and determining the width and distribution of each section of the magnetic steel, the air gap magnetic density waveform approaches sine distribution; harmonic components are reduced to the greatest extent; the eddy current loss of the magnetic steel and the torque pulsation of the motor are simultaneously reduced; and the electromagnetic performance of the motor is enhanced. Furthermore, the multiple sections of the magnetic steel are arranged in the circumference along the rotor; the highest rotating speed of the safe operation of the rotor is greatly enhanced on machinery; the radial thickness which is needed by the magnetic circuit of the rotor is obviously reduced on the structure; the rotational inertia and weight of the rotor are reduced; the dynamic response of the motor is improved; and the requirements of a high-speed driving system on the performance of the motor are met.

The invention discloses a multitooth magnetic bridge type hybrid excitation magnetic flux switching motor. Permanent magnets, an armature winding and a single-phase excitation winding are installed on a stator; the tooth number of the stator is four times of the number of the permanent magnets; and part of a rotor part is a salient pole, and a rotor has no winding or permanent magnets and has simple and firm structure. An air gap magnetic field comprises an electric excitation magnetic field generated by the excitation winding and a magnetic field generated by the permanent magnets and is adjusted by changing the magnitude and the direction of excitation current, thereby improving the rotating speed operating range and the magnetic weakening capability of the motor. An electric excitation magnetic force line is connected with a magnetic bridge for closing after penetrating through an iron core at the top of the permanent magnets, which is beneficial to reducing the electric excitation ampere turns. The invention has parallel connecting structure of the excitation winding and the permanent magnet in space, bipolarity of phase magnetic flux, large magnetic chain change amplitude value and higher torque output capability and power density and is suitable for a low-speed straight application occasion.

The invention provides a double-stator high-power-density flux switching permanent magnet motor. The double-stator high-power-density flux switching permanent magnet motor comprises an outer stator, an inner stator and a rotor, and air gaps exist between the rotor and the stators. The rotor is composed of magnetic blocks, the magnetic blocks are evenly distributed in space and can be arranged at intervals or connected into a whole through connecting bridges; the outer stator is composed of U-type magnetic blocks, tangential magnetized permanent magnets and concentrated windings; every permanent magnet is clamped between the corresponding two neighboring U-type magnetic blocks, and the concentrated windings are arranged inside the grooves of the U-type magnetic blocks and house the permanent magnets; the neighboring permanent magnets magnetize alternately each other in the tangent direction; the radial axises of U-type magnetic blocks of the inner stator and the outer stator mutually coincide, and the magnetic teeth of the U-type magnetic blocks of the inner stator and the outer stator are opposite to each other; the magnetizing directions of the permanent magnets of the inner stator and the outer stator, which are identical in spatial position, are inverse, and the concentrated windings of the inner stator and the outer stator, which are identical in spatial position, are on the same phase. Compared with the prior art, the double-stator high-power-density flux switching permanent magnet motor omits rotor magnetic yokes, reduces the size of the rotor and the consumption of iron, improves the power density and the efficiency and can be applied to power systems such as wind power generation, electric vehicles and ships and warships.

The invention discloses a magnetic field modulation hybrid excitation motor and a multi-working-wave design method thereof. The motor comprises a stator and a rotor, wherein the stator comprises a stator iron core, two sets of windings and permanent magnets, the two sets of windings comprise an armature winding and an exciting winding, the stator iron core is designed as an open slot, one set of windings is distributed in the open slot of the stator iron core, and is wound on one stator tooth in a centralized manner, the outer surface of each stator tooth is provided with a groove, the other set of windings is placed in the groove of the stator tooth, each stator tooth is split into two modulation teeth through the groove, one permanent magnet is placed on each modulation tooth, the otherwinding is wound on two adjacent modulation teeth formed by splitting different stator teeth in a centralized mode, and the magnetizing direction of the permanent magnets is consistent with or opposite to the direction of a magnetic field formed by the excitation winding on the modulation teeth. According to the invention, the permanent magnet magnetomotive force and the excitation magnetomotive force are connected in parallel on the magnetic circuit and are independent from each other, so that the risk of irreversible demagnetization caused by the introduction of an excitation current permanent magnet is avoided, and the effective exertion of the magnetic regulation capability is ensured.

The invention discloses a direct-axis magnetic field enhanced type wide-range speed control permanent magnet brushless motor for an electric automobile. A magnetic barrier fills each slot of a rotor, and the magnetic barriers are symmetrical relative to a centerline, i.e., a quadrature axis, of slot parts of the rotor; four sections of arc-shaped permanent magnet steel are fixedly embedded on each tooth part of the rotor, the four sections of arc-shaped permanent magnet steel are divided into an inner layer and an outer layer, two sections are arranged on each layer, the two sections of permanent magnet steel on each layer are the same in structure and are symmetrical relative to a centerline, i.e., a direct axis of the tooth parts of the rotor, the two sections of permanent magnet steel on the same layer do not run through each other and are not connected with each other, and an arc-shaped magnetic bridge is formed between the two sections of permanent magnet steel; a circle center of each section of permanent magnet steel is located on the diameter of the rotor; the direct-axis inductance of the motor is larger than the quadrature-axis inductance, so that the motor can adopt a control method with zero direct-axis current and can also adopt a direct-axis magnetic field enhanced control method during low-speed operation or startup, and can adopt a coordinated control method of direct-axis magnetic field enhancement and slight direct-axis magnetic field weakening during high-speed operation, and the speed control range is wider.

The invention discloses a partitioned stator type hybrid excitation motor in the field of electricians and motors. The partitioned stator type hybrid excitation motor is characterized in that the external part of a rotating shaft is provided with an inner stator, a middle rotor and an outer stator which are coaxially arranged in sequence from the inside out, the outer stator is uniformly provided with 36 outer stator teeth along the circumferential direction, and the outer stator teeth are wound with armature windings; the inner stator is uniformly provided with 36 inner stator teeth along the circumferential direction, the inner stator teeth are wound with centralized excitation windings, the middle rotor is forming by uniformly placing 16 magnetic conduction blocks and 16 permanent magnets along the circumferential direction in an alternative manner, the magnetic conduction blocks and the permanent magnets are identical in inner diameter and outer diameter, side surfaces of the magnetic conduction blocks and the permanent magnets are closely fit together, magnetizing directions of adjacent two permanent magnets differ 90 degrees, and the N poles of 16 permanent magnets along the clockwise circumferential direction reversely rotate by 90 degrees anticlockwise in sequence, so that permanent magnet flux at the armature winding side when the permanent magnets carry out excitation independently is effectively increased, and influences imposed on the excitation winding side by a permanent magnetic field are reduced while improving the power density of the motor.

The invention discloses a disc type double-stator hybrid excitation motor. According to the hybrid excitation motor designed in the invention, based on the principle of magnetic field modulation, the combination of a disc type permanent magnet motor and an electric excitation system is realized. The hybrid excitation motor has the characteristics of high power density, high moment density, a short axial size and a compact structure and also has the advantages of flexible adjustment of an excitation magnetic field and a wide speed regulation range, and thus the hybrid excitation motor can be applied to the field of electric vehicle hubs. The motor comprises two stators and one disc type rotor. An excitation winding and an armature winding are respectively arranged at the stators at two sides, and a permanent magnet pole and a core pole are distributed on the rotor. By using the magnetic field modulation technology, the permanent magnet on the rotor and the excitation winding on an inner stator generate a magnetic field same with an armature winding pole pair number at an external air gap, and a permanent magnet pole and an iron pole are uniformly distributed on the rotor. By using the magnetic field modulation technology, the permanent magnet on the rotor and the excitation winding on the inner stator generates a magnetic field same with the armature winding pole pair number at the external air gap, and thus the electromechanical energy conversion is realized. The back EMF waveform is improved through the design of a multi-phase structure and a three-layer fractional-slot integrated winding, and the reliability and fault tolerance of the motor are improved at the same time.

The invention relates to a linear permanent magnet motor operating mechanism of a high-voltage circuit breaker, comprising a stator core, a rotor core, drive rods and permanent magnets, wherein the stator core is a box body; the rotor core is arranged in the stator core; the drive rods arranged on both ends of the rotor core penetrate through shells positioned on the upper and the lower ends of the rotor core and can move up and down; the side wall of the stator core is provided with the permanent magnets; upper and lower adjacent permanent magnets are opposite in polarity; the permanent magnets positioned on the left and the right edges of the box body are same in polarity placement directions; stator salient poles with the number of integral multiples of a phase number are arranged on the inner side wall of the stator core and between the two adjacent permanents and are provided with armature coils; the outer side wall of the rotor core is provided with rotor salient poles; when therotor core is positioned on a highest position, the stator salient pole positioned on the uppermost end of the stator core just faces to the rotor salient poles; and when the rotor core is positionedon a lowest position, the stator salient pole positioned on the lowest end of the stator core just faces to the rotor salient poles.

The invention discloses a variable salient pole rate permanent magnet motor and a design method thereof, the variable salient pole rate permanent magnet motor comprises a stator and a rotor, the rotor comprises a plurality of modularized independent rotor units (3), segmented and regional saturation of a rotor magnetic circuit is realized by means of differentiated rotor material attributes, quadrature-axis inductance is indirectly adjusted by adjusting armature current, and the salient pole rate of the rotor is improved. Therefore, the salient pole rate of the motor is changed. According to the invention, the reverse salient rate characteristic can be realized at a low speed, the torque output capability of the motor is improved, and the irreversible demagnetization risk of the motor is reduced; the positive salient pole rate characteristic is realized at a high speed, the reluctance torque is fully utilized, and the loading capacity of the motor at the high speed is improved.

The invention provides a long-stroke linear permanent magnet motor operation mechanism of a high-voltage breaker. Long-stroke linear permanent magnet motor operation mechanism of high-voltage breaker is characterized in that the operation mechanism comprises a stator core, a rotor core, a driving rod and a permanent magnet, wherein the stator core is a box body; the rotor core is disposed in the stator core; the driving rod disposed at two ends of the rotor core passes through the upper and lower end shells of the stator core and can move up and down; the inner side wall of the stator core isprovided with a stator salient pole; the permanent magnet is disposed in the stator salient pole; the polarities of the upper and lower adjacent permanent magnets are opposite; the polarity arrangingdirections of the permanent magnets at left and right sides of the box body are the same; the stator salient pole is provided with an armature coil; the top part of the stator salient pole is provided with a pole shoe; the outer side wall of the rotor core is provided with a rotor salient pole; when the rotor core is located at the highest position, the lower half section of the stator salient pole at the uppermost end of the stator core faces the rotor salient pole; when the rotor core is located at the lowest position, the upper half section of stator salient pole at the lowest end of the stator core faces the rotor salient pole.

The invention discloses a low-space harmonic single/double-layer winding radial flux five-phase permanent magnet synchronous motor, belongs to the field of motors, and aims to solve the problem that the harmonic content in magnetomotive force synthesized by a stator winding of a five-phase permanent magnet synchronous motor adopting a fractional slot concentrated winding is relatively large. The motor comprises a stator and a rotor, the stator is coaxially arranged outside the rotor, the stator is provided with ten stator slot units in the circumferential direction, the winding modes of five-phase windings are the same, and the phase differences of the B-phase winding, the C-phase winding, the D-phase winding and the E-phase winding are 72 degrees, 144 degrees, 216 degrees and 288 degrees in sequence relative to the A-phase winding in the spatial position; each phase of winding comprises two groups of coils, the space position difference of two pairs of coils in each group is 180 degrees, each pair of coils is arranged in one double-layer winding groove and two single-layer winding grooves in the two sides, the winding directions of the two coils in each pair are opposite, and the coil pitch is gamma; the two coils are connected in series to form a winding; and an included angle xi value and a coil pitch gamma value of the two groups of coils in the spatial position are limited so as to weaken the amplitude of near-pole sub-harmonics in the synthesized magnetomotive force.