60results about How to "Reduce back EMF" patented technology

The invention discloses an exciting current given device for an induction motor of an electric vehicle. On the basis of the prior art, the exciting current given device is additionally provided with an exciting current limiting calculation module and a limiting PI (proportional integral) control module. When the induction motor normally runs, the calculated amplitude limiting maximum value (isd.Max) of the exciting current decreases along with the increase of the real synchronous speed omega e. The exciting current isdref of a voltage loop PI controller decreases under the condition of invariable maximum voltage vector (usm). Due to the decrease of the exciting current (isdref), the counter electromotive force of the induction machine decreases, therefore, under the condition of invariable busbar voltage uDC, the induction motor can rise to a higher rotating speed. In addition, according to the exciting current given device of the induction motor of the electric vehicle, the calculation of switching points among a constant torque area, a constant power area and a constant voltage area is eliminated, so that the level jump of output exciting currents caused by the inaccurate calculation of switching points can be effectively prevented, the given value of the exiting currents can vary stably, the joggling of the induction motor control caused by the level jump of the given valueof the exciting currents is reduced, and the safety of the induction motor control is improved.

The invention relates to a novel synchronous electric motor and an electric motor control system thereof, and realizes the special advantages of 'one electric motor and three states' and 'one state and multiple characteristics'. The invention is characterized in that on the basis of the existing permanent magnetic synchronous electric motor used for an electric automobile and a controller thereof, an exciting winding is added on a rotor, and the current of the exciting winding is controlled by an electric motor controller to change the intensity of a magnetic field of the electric motor so as to change the external characteristics of the electric motor and achieve the target of 'one electric motor and multiple characteristics'. The characteristic overcomes the defects of insufficient torque and poor dynamic property when the existing permanent magnetic synchronous electric motor used for the electric automobile is used for climbing, simultaneously solves the problem of insufficient electric motor speed when the electric automobile is in cruise control or high-speed running, and completely meets the requirements on road conditions of the electric motor used for the electric automobile. An advanced topology and control algorithm is adopted for the electric motor controller adaptive to the invention, and the electric motor is controlled more efficiently, and has better dynamic property and a longer running range.

The invention discloses a rotor of a permanent magnet motor. The rotor comprises a rotor core with a plurality of installation grooves and permanent magnets installed in the installation grooves. The rotor core is provided with a central hole and a plurality of sections of cylindrical surfaces, a magnetic bridge is connected between adjacent cylindrical surfaces, the outside surface of each magnetic bridge is much closer to the central hole of the rotor core relative to the cylindrical surfaces, the outside surface of each magnetic bridge is outwards concave from the installation grooves to form a groove in the magnetic bridge, and the widths of the grooves are smaller than that of those of the installation grooves. Compared with the prior art, the rotor of the permanent magnet motor has the advantages that the magnetic bridges and the grooves are arranged to allow a motor with the rotor to obtain low cogging torque, reversed electromotive force tending to the sine and low load torque pulsation. The rotor has the advantages of being simple in manufacturing process, high in mechanical strength, low in noise and high in demagnetization-resistance performance due to appropriate multi-section arc or the line-section magnetic bridges, and the rotor is applicable to motors of roller washing machines.

The invention discloses a motor stator and a motor with the same. The motor stator comprises a stator iron core, wherein the stator core comprises a stator yoke part and stator tooth parts; the stator yoke part is annular, each stator tooth part is arranged at the inner side of the stator yoke part, and each stator tooth part radially extends along the stator yoke part; six stator tooth parts are arranged at the inner side of the stator yoke part along a circumference at intervals; a winding coil wound on the stator yoke part, wherein the winding coil is wound between each two adjacent stator tooth parts, two opposite winding coils on the space are mutually connected in parallel and cooperated as one phase, three phases of winding coils are connected end to end to present a delta-delta connection. According to the motor stator disclosed by the invention, two radially opposite winding coils are mutually connected in parallel and cooperated as one phase, and three phases of winding coils are connected end to end to present the delta-delta connection. Therefore, the line back electromotive force and the winding difficulty can be lowered.

The invention discloses a flux-adjustable magnet vane structure for a permanent magnet motor rotor. A plurality of magnetic steel grooves are embedded into a rotor core; magnetic steel is embedded into the magnetic steel grooves; magnet vanes are arranged at the two ends of the rotor core respectively; a plurality of magnetic conductive sliding block holes which are in one-to-one correspondence with the magnetic steel grooves are distributed on the magnet vanes; slidable sliding blocks are embedded into the sliding block holes; an elastic component used for controlling displacement of each sliding block is arranged on one side of the corresponding sliding block hole; and the effective area of the magnetic steel is controlled through sliding of the sliding blocks. During use, the magnet vanes are arranged at the two ends of the rotor core, the flux leakage area of the magnetic steel is controlled by the movement of the sliding blocks, an function of automatic adjustment of the rotor flux along with the motor operation rotating speed is achieved, and the problems of high counter electromotive force, difficulty in weak magnetism, low operation efficiency and large vibration noise of ahigh-speed area in a wide speed regulation range of the motor in the prior art are solved.

Provided is a motor driving device with a fault tolerance function. Six windings of a permanent magnet motor (1) are distributed sequentially in a mutually staggered 60-degree electric angle in a stator. The A, C, E ends of the six-phase winding are connected with the alternating current output phase of a first three-phase inverter (3), and the B, D, F ends of the six-phase winding are connected with the alternating current output phase of a second three-phase inverter (6); the other ends, a and d, b and e, c and f, of the six-phase winding are connected with the three-phase alternating current input ends of a rectifier bridge (51) of a short-circuiting device; a seventeenth IGBT module (52) of the short-circuiting device (5) is connected with the rectifier bridge (51) of the short-circuiting device (5) in parallel, and the on-off of the seventeenth IGBT module (52) controls circuit shorting and opening of a circuit on the alternating current input side of the rectifier bridge (51). A ninth IGBT module (9) is connected with the first three-phase inverter (3) in parallel, a tenth IGBT module (10) is connected with the second three-phase inverter (6) in parallel, the on-off of the ninth IGBT module (9) or the tenth IGBT module controls circuit shorting and opening of the A, C, E ends or the B, D, F ends of the six-phase winding.

The invention provides an integrated double-motor distributed drive electric drive axle. The drive axle comprises an integrated power assembly, an axle housing and a hub reduction system, the integrated power assemblies are respectively arranged at the front end and the rear end of the axle housing; the integrated power assembly comprises a driving motor, a speed reducer and a differential mechanism; the driving motor drives the speed reducer and the differential; the hub reducers are respectively arranged at the left and right ends of the axle housing; the hub reduction gear arranged at the left end of the axle housing is in transmission connection with the differential mechanism of the integrated power assembly arranged at the rear end of the axle housing through a first half shaft; thehub reduction gear arranged at the right end of the axle housing is in transmission connection with the differential mechanism of the integrated power assembly arranged at the front end of the axle housing through the second half shaft, and therefore the integrated power assembly has the advantages that the weight of the assembly is reduced, the overall efficiency of the axle is improved, and meanwhile the space utilization rate of the whole vehicle is increased.

The invention discloses a permanent magnet DC brushless motor for a pure electric vehicle, belonging to the technical field of permanent magnet DC current motor. The permanent magnet DC brushless motor for a pure electric vehicle comprises a stator, a rotor and a motor shaft; the stator comprises stator iron cores which are uniformly and internally distributed on the inner side of the stator; the two ends of the stator iron core are provided with insulation skeletons; the insulation skeleton is provided with a circuit board assembly; the rotor comprises a rotor iron core and a plurality of permanent magnets, the number of which is even; when a radial type rotor is adopted, the shapes of the permanent magnets are characterized in that: the permanent magnet is of a strip shape with the inner side and the outer side being arc, the permanent magnet is of a shuttle shape with double faces being projected and two sides being flushed and the permanent magnet is of a strip shape with an arc-shaped outer edge and single-face projected. The permanent magnet DC brushless motor for the pure electric vehicle can improve the working point of the permanent magnet, and enhances the demagnetization resistance capability and overloading capability of the motor. When the tangential type rotor is adopted, the internal of the rotor iron core which is close to the motor shaft is provided with a sector-shaped groove; and a conductive magnetic sliding block is arranged inside the sector-shaped groove. The adoption of the conductive magnetic sliding block can reduce the counter electromotive force of the motor, improves the highest rotation speed of the motor, and satisfies the low load of the pure electric vehicle and the special needs for high speed.

The invention relates to a rotor structure for a synchronous reluctance motor. A plurality of groups of air layer structures are distributed in the circumferential direction of a rotor. A circle of lightening holes are formed in the middle of the rotor, and each air layer structure comprises a first layer of air groove group and a second layer of air groove group. The first air groove set comprises a first straight-axis air groove formed in the middle, and the two sides of the first straight-axis air groove are each provided with a first quadrature-axis air groove. The second air groove set comprises two second straight-axis air grooves formed in the middle, and a second quadrature-axis air groove is formed in the outer side of each second straight-axis air groove. Through structural optimization processing, arrangement of the air grooves, arrangement of the reinforcing ribs and placement of the magnetic steel, the peak torque, efficiency and power factors of the motor are effectivelyimproved, the counter electromotive force of a high-speed weak magnetic area is reduced, and the speed regulation range of the motor is remarkably improved.

The invention discloses a speed regulation permanent magnet synchronous motor based on variable number of turns of windings. The speed regulation permanent magnet synchronous motor comprises three-phase windings, each winding comprises a plurality of serially connected series winding units, each series winding unit comprises one winding and two winding control structures, one winding control structure and the winding after parallel connection are parallelly connected with the other winding control structure, the winding control structures are used for controlling whether current is led in ornot when the speed regulation permanent magnet synchronous motor works, the connection number of turns of the series winding units is changed to control the counter potential of the speed regulation permanent magnet synchronous motor, weak magnetic current is reduced, and performances are improved. According to the speed regulation permanent magnet synchronous motor, the winding control structuresserially connected with the windings are disconnected, the winding control structures parallelly connected with the windings are closed, the windings are bypassed in a circuit-breaking manner, the number of turns of the windings connected into the speed regulation permanent magnet synchronous motor during work is decreased, the counter potential is reduced, the number of rated points is increased, and a speed regulation range is widened.

The invention is applied to the field of a motor, and especially relates to a DC separately excited machine controller. The DC separately excited machine controller comprises a speed proportion integration modulation unit, a first current proportion integration adjusting circuit, a pulse width modulation unit and a DC motor which are successively connected. The two ends of a speed negative feedback circuit are respectively connected with the speed proportion integration modulation unit and the DC motor, the two ends of an armature current control unit are respectively connected with the input end and the output end of the DC motor, and an excitation current control unit is connected with the output end of the DC motor and a system given excitation current output end. Through applying the technical scheme provided by the invention, the purposes of preventing the DC motor from being affected by a temperature factor and preventing a body from a landslide are achieved.

The invention discloses a three-phase high-speed step motor driver with a full step angle of 2.4 degrees. The three-phase high-speed step motor driver comprises a master control CPU (central processing unit), a pulse control signal input interface circuit, a current sampling unit and regulating unit, a switch power supply and power input EMI circuit, a 6-way PWM (pulse width modulation) signal output isolation circuit, a master control power module and auxiliary circuit, a step motor three-phase winding U/V/W output end, a power-on sequence control circuit and a power-down parameter storage unit. In the automatic equipment application field, an application speed range of a traditional step motor driver is expanded by 30-50% under conditions with requirements of positioning or speed regulating, and irreplaceable application solution schemes are provided in some positioning control with requirements of frequent forward and reverse rotation, so that equipment production efficiency is greatly improved.

The invention relates to a permanent magnet brushless motor, in particular to an integrated self-adaptive flux shunt speed multiplying method of a permanent magnet brushless speed-regulation motor, which is characterized in that a stator axially moves relative to a rotor so as to regulate the main flux of an air gap, and the process is automatically carried out by means of a centrifugal mechanismwith specific functional relation, and the structure is integrated. The permanent magnet brushless motor is driven to rotate by a controller; a rotating-speed induction magnetism-regulating mechanismcomprises a centrifugal mechanism and a flux shunt; the centrifugal mechanism generates the centrifugal force F omega=rmomega2, which is transferred to the Z direction and turned to Fz; the Fz leads the permanent magnet rotor to move axially, and the rotor and the stator are gradually staggered at a certain position delta z, so that a magnetic circuit is changed, one part of the flux phi d is shunted by the flux shunt, and the flux phi m passing through a winding is reduced; as a result, the output torque T of the motor is reduced at the same time as the rotating speed omega is increased, andthe power (P=T*omega) is remained unchanged, so as to realize the characteristic of speed regulation of the permanent magnet motor at constant power.

The invention discloses a coaxial electric drive axle assembly with self-locking and disengaging functions and a working method. The coaxial electric drive axle assembly is capable of preventing wheels from slipping, power separation and coaxial miniaturization. Comprising a stator assembly, a rotor assembly, an axle housing, a planetary gear assembly, an electromagnetic clutch, a self-locking differential assembly, a right half axle and a left half axle, the rotor assembly is provided with an axial inner hole and arranged on the left half axle in a sleeving mode, and the planetary gear assembly comprises a sun gear, a planetary pinion, a planetary bull gear, a gear ring and a planet carrier; the planetary pinion and the planetary bull gear are mounted on the planetary carrier, the planetary pinion and the planetary bull gear are coaxially fixed, the planetary pinion is meshed with the sun gear, the planetary bull gear is meshed with inner teeth of the gear ring, and the gear ring is fixed to the axle housing to form an epicyclic gear train; the electromagnetic clutch is installed on the right side of the planetary gear assembly and used for transmitting power of the planetary gear assembly to the self-locking differential assembly, and the right half shaft and the left half shaft are both matched with the self-locking differential assembly.