43results about How to "Reduce higher harmonic content" patented technology

The invention discloses a hybrid excitation type high-speed permanent magnet motor rotor and a manufacturing method. The hybrid excitation type high-speed permanent magnet motor rotor comprises a rotating shaft, a sintered permanent magnet unit, a magnetic powder adhesive film and carbon fiber composite unit and a rotor sheath which are sequentially arranged from inside to outside in the radial direction, wherein the sintered permanent magnet unit is composed of sintered permanent magnet blocks, epoxy resin filler and a carbon fiber layer, the sintered permanent magnet blocks are equal in axial length and unequal in radial thickness, and each magnetic pole of the high-speed permanent magnet motor rotor is formed by the sintered permanent magnet blocks in the circumferential direction according to the arrangement mode that the middle is high and the two ends are low; and the magnetic powder adhesive film and carbon fiber composite unit consists of a plurality of magnetic powder adhesivefilm and carbon fiber composite subunits composed of magnetic powder adhesive film layers and carbon fiber layers, the number of the magnetic powder adhesive film layers and the number of the carbonfiber layers are different, and the sum of the number of the magnetic powder adhesive film layers and the number of the carbon fiber layers is not changed. According to the hybrid excitation type high-speed permanent magnet motor rotor and the manufacturing method, the mechanical strength of the motor rotor can be improved, the eddy current loss of the motor rotor is reduced, and the allowable linear speed of the motor rotor is improved, thereby solving the problems of large eddy current loss, high temperature rise and low allowable linear speed of the traditional high-speed permanent magnet motor rotor.

The invention relates to a permanent magnet motor. The permanent magnet motor comprises a stator, a rotor and a rotating axle, wherein the rotor forms a plurality of rotor magnetic poles, each rotor magnetic pole is provided with an arc-shaped surface and first and second inclined sections extending from both sides of the arc-shaped surface, the second inclined sections of the adjacent rotor magnetic poles are connected via a tangent section to form a sunken space, a plurality of magnets are arranged in all the rotor magnetic poles, both end parts of each magnet are arranged adjacent to two second inclined sections, and the center part of each magnet is sunken toward the center of the rotor, so as to fully improve the efficiency of the motor.

The invention provides a magnetically controlled reactor and a method. Magnetic valves are arranged on one or more pairs of ironic core pillars with coils, under the condition that the shape and sizeof the magnetic valves are set to be capable of making a magnetized curve of an ironic core of the magnetically controlled reactor formed by sequentially connecting line segments a1, a2 and a5, wherein a1 is the starting point of the magnetized curve, and corresponding magnetic induction intensity is zero; a2 is a point between the starting point of the magnetized curve and a knee point, and magnetic induction intensity B2 corresponding to a2 is between magnetic induction intensity corresponding to zero and magnetic induction intensity corresponding to the knee point; magnetic induction intensity corresponding to a5 is equal to that corresponding to the knee point, and is the peak value of the maximum value of reactance current of the magnetically controlled reactor. By designing the magnetic values, the ideal magnetized curve of the ironic core of the magnetically controlled reactor can be obtained, so that the content of higher harmonic of the magnetically controlled reactor is minimum.

The invention discloses a high-speed permanent magnet motor rotor with a sine magnetomotive force distribution rule and a manufacturing method. The high-speed permanent magnet motor rotor comprises arotating shaft, a sintered permanent magnet unit, a magnetic powder adhesive film and carbon fiber composite unit and a rotor sheath which are sequentially arranged from inside to outside in the radial direction, wherein the rotor sheath is formed by multiple layers of carbon fibers III, the magnetic powder adhesive film and carbon fiber composite unit is composed of a plurality of magnetic powderadhesive film and carbon fiber composite subunits, and each magnetic powder adhesive film and carbon fiber composite subunit is composed of a magnetic powder adhesive film layer block, an adhesive film layer block and a carbon fiber layer; and the number of the magnetic powder adhesive film layer blocks and the number of the adhesive film layer blocks are the same as the number of the sintered permanent magnet blocks, and the sum of the polar arc coefficients of the magnetic powder adhesive film layer blocks and the polar arc coefficients of the adhesive film layer blocks is always 1. According to the high-speed permanent magnet motor rotor, the mechanical strength of the motor rotor can be improved, the eddy-current loss of the motor rotor is reduced, and the allowable linear speed of the motor rotor is increased, so that the problems of large eddy-current loss, high temperature rise and low allowable linear speed of the traditional high-speed permanent magnet motor rotor are solved.

The invention discloses a direct-driving type torque motor. The torque motor comprises a rotating shaft, a front end cover, a rear end cover, a machine shell, a rotor, a stator and a plurality of permanent magnets. The rotor is of a cylindrical structure and is mounted on the rotating shaft, the stator is fixed to the machine shell, the rotating shaft, the rotor and the stator are sequentially and coaxially arranged, the permanent magnets are of a strip-shaped structure, the cross section of each permanent magnet is a sealed pattern formed by sequentially connecting a first arc, a first straight line, a second arc and a second straight line, each closed pattern is symmetric relative to the straight line of the corresponding first arc and the straight line of the corresponding second arc, the curvature of each first arc is larger than that of the corresponding second arc, the permanent magnets are evenly arranged on the outer wall of the rotor, and are parallel to a central shaft of the rotor, and the face where the second arc in each permanent magnet is located is tightly attached to the outer wall of the rotor. According to the torque motor, the torque pulsation and the vibration noise of the motor can be effectively reduced, the demagnetization effect on the permanent magnets in flux-weakening control and torque output of the motor at low speed are ensured, the tooth groove torque ripple is effectively reduced, and the machining precision is improved.

The invention relates to a power inverter circuit, in particular to a precise inverter circuit. The precise inverter circuit adopts an arithmetic unit 4 to output biphasic sine pulse width modulation (SPWM) signals, the SPWM signals and output square signals together control a controllable inverter bridge to work, output pulse voltage area is equal to area of selected output sine wave in a corresponding interval, and by changing frequency and amplitude of modulating wave, frequency and amplitude of output voltage of the inverter circuit can be adjusted. The voltage pulse series can greatly reduce higher harmonic components in load current.

Provided is a permanent-magnet synchronous motor whereby a 12f component of torque ripple can be minimized when using a radial anisotropic ring magnet in a small-diameter motor. Said synchronous motor has Z annular stators with wire windings and a permanent magnet with 2P poles, Z/(3·2P) being either 2/5 or 2/7 (3 being the number of phases). If a radial anisotropic ring magnet is used as the permanent magnet, a 12f component of torque ripple can be minimized by magnetizing the radial anisotropic ring magnet such that the ratio of a flat region to a transition region in the magnetization waveform of one magnetic pole has an appropriate value given tw/h, where h is the tip width of flange parts constituting the tip sections of the stators and tw is the base width of said flange parts.

The invention discloses a rotor core structure of an asynchronous starting permanent magnet synchronous motor, and the structure comprises a rotor punching sheet group which is formed by superposing aplurality of rotor punching sheets, and a rotor magnetic steel which is embedded on the rotor punching sheets, wherein the rotor punching sheets are annular, the rotor punching sheets are provided with damping holes, and the damping holes are located in the annular edge; damping strips are arranged in the damping holes in a penetrating mode, heat dissipation channels are formed in the damping holes, the heat dissipation channels extend to the outer ring face of the rotor punching sheet, arc-shaped magnetic steel grooves are formed in the rotor punching sheet, rotor magnetic steel is embeddedin the magnetic steel grooves, the rotor magnetic steel adopts a magnetizing mode of a Halbach array, and axial ventilation holes are formed in the rotor punching sheet. According to the rotor core structure of the asynchronous starting permanent magnet synchronous motor, the 380V-8p-30kW motor has good operation performance, the noise and vibration of the motor can be reduced, and meanwhile, theworking performance of the motor is improved.

The invention discloses a stator assembly and a motor. The stator assembly comprises a stator core and a stator winding. The stator core has 36 stator slots. The stator winding comprises A, B, and C phases of stator windings, the common end of the A, B, and C phases of stator windings is in a star connection or triangular connection. The A, B, and C phases of stator windings comprise four sets of coil groups, and each set of coil groups comprises a large coil, a middle coil and a small coil. The large, middle and small coils of each set of coil groups of the A, B, and C phases of stator windings are uniformly embedded into the 36 stator slots according to a rule that the winding pitches of the large coils are 8, the winding pitches of the middle coils are 6, and the winding pitches of the small coils are 4, wherein the a double-winding design is employed by the A, B, and C phases of stator windings, and the elements of two different phases are placed in each one of the stator slots. According to the invention, the structure of the motor stator winding is improved, the magnetic saturation of a motor stator magnetic circuit is reduced, and the output performance of the motor is improved.

The invention discloses a magnetically controlled reactor, comprising a first terminal, a second terminal, a closed-loop iron core and a controllable rectifying circuit, wherein the closed-loop iron core comprises four iron core legs, the sections of the four iron core legs have the same area, two ends of each two iron core legs are connected by magnet yokes, and two iron core legs placed in the middle portion of the closed-lop iron core are respectively wound with a coil; the dotted terminals of the first and second coils are respectively connected with the first terminal while the non-dotted terminals are respectively connected with the output end of the controllable rectifying circuit; the input end of the controllable rectifying circuit is connected with an external control circuit for rectifying under the control of control signals output by the external control circuit. The magnetically controlled reactor provided by the invention has the advantages of simple structure and fewer higher harmonic waves.