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CN-121984264-A - Harmonic self-starting permanent magnet synchronous motor

CN121984264ACN 121984264 ACN121984264 ACN 121984264ACN-121984264-A

Abstract

The invention discloses a harmonic self-starting permanent magnet synchronous motor, which comprises rotor winding coils with different pitches, wherein the magnitude and the direction of induced electromotive force generated in different pole-to-number magnetic fields generated by a stator are different, which is equivalent to the connection of an additional resistor, so that the rotor resistance is increased when the motor is started, and the motor has good starting performance; during normal operation, stator magnetomotive force harmonic waves are counteracted by changing a stator winding connection method, the motor is restored to a conventional motor state, at the moment, the rotor resistance is restored to be normal, the additional resistance is equivalent to cutting off, and the motor has high operation efficiency, so that the motor starting torque can be increased without additional starting resistance by using the rotor winding, and the structural characteristics of no slip ring and no electric brush of the motor are maintained.

Inventors

  • CAI MENGXIA
  • KAN CHAOHAO

Assignees

  • 合肥工业大学

Dates

Publication Date
20260505
Application Date
20260407

Claims (10)

  1. 1. The harmonic self-starting permanent magnet synchronous motor is characterized by comprising a stator and a rotor, wherein two sets of relatively independent windings are arranged on the stator, namely a starting winding and an auxiliary winding respectively, and a set of permanent magnet and two sets of rotor windings are arranged on the rotor; the starting winding and the auxiliary winding all generate pole pair number of And produces a pole pair number of fundamental magnetic fields of 、 A harmonic magnetic field with the same rotation direction as the fundamental magnetic field; the two sets of rotor windings are all according to Counter electrode The phase normal phase band is respectively arranged into a first rotor winding and a second rotor winding, and the coil pitch of the first rotor winding Full pole pitch arrangement corresponding to the counter pole, second rotor winding coil pitch The number of slots of 2 times of the pole pitch corresponding to the antipodal harmonic wave, the first rotor winding Phase 1 Branch, and the first of the second rotor windings Phase 1 The branches being connected in parallel, when the branches of the first rotor winding are in the stator with the branches of the second rotor winding When the fundamental wave magnetic field is generated, the phase difference between the central axis of the magnetic field induced by the branch of the first rotor winding and the branch of the second rotor winding is Electric angle, and second rotor winding Phase 1 Branches, in the form of stators When the counter-pole magnetic field is applied, the vector composite value of the induced electromotive force is equal to zero.
  2. 2. A harmonic self-starting permanent magnet synchronous motor according to claim 1, wherein when the motor is started, a starting winding on a stator is connected to a power grid, and the starting winding generates a pole pair number of Is the fundamental magnetic field and the pole pair number is 、 And (2) harmonic magnetic field of 、 、 The direction of rotation of the counter-pole magnetic fields is the same.
  3. 3. A harmonic self-starting permanent magnet synchronous motor according to claim 2, wherein the auxiliary winding on the motor stator generates a pole pair number of the auxiliary winding when the auxiliary winding is connected to a power grid Is the fundamental magnetic field and the pole pair number is 、 And (2) harmonic magnetic field of 、 、 The direction of rotation of the counter-pole magnetic fields is the same.
  4. 4. A harmonic self-starting permanent magnet synchronous motor according to claim 3, wherein the rotor is provided with a set of pole pairs Is a permanent magnet of a magnetic core.
  5. 5. A harmonic self-starting permanent magnet synchronous motor according to claim 4, wherein the motor start winding generates Generated by opposite magnetic field and auxiliary winding Antipodal magnetic field, at phase difference The electrical angles, i.e. the spatially in-phase inside the motor, the magnetic fields are superimposed on each other.
  6. 6. A harmonic self-starting permanent magnet synchronous motor according to claim 5, wherein the motor start winding generates 、 Opposite-pole harmonic magnetic field and auxiliary winding 、 Antipodal harmonic magnetic fields differing in phase respectively The electrical angles, i.e. the spatially opposite phases inside the motor, cancel each other out the magnetic fields.
  7. 7. A harmonic self-starting permanent magnet synchronous motor according to claim 6, wherein when the motor start winding and auxiliary winding are connected to a power grid simultaneously, the spatially synthesized magnetic field generated by the start winding and auxiliary winding is A dipole magnetic field.
  8. 8. A harmonic self-starting permanent magnet synchronous motor according to claim 7, wherein the motor is a motor with respect to The counter-pole, both sets of rotor windings have high winding coefficients when both sets of rotor windings are in the stator When in the opposite pole magnetic field, the two sets of rotor windings are strong in electromagnetic coupling with the stator side.
  9. 9. A harmonic self-starting permanent magnet synchronous motor according to claim 8, wherein the motor is a motor with respect to The counter-pole, first rotor winding has a high winding coefficient, the second rotor winding coefficient is close to zero, when the two sets of rotor windings are in the stator In the opposite pole magnetic field, the electromagnetic coupling between the first rotor winding and the stator side is strong, while the electromagnetic coupling between the second rotor winding and the stator side is weak, namely the second rotor winding is equivalent to a section of resistor.
  10. 10. A harmonic self-starting permanent magnet synchronous motor according to claim 9, wherein the first rotor winding of the motor is the first winding Phase 1 A branch circuit of Branch, and the first of the second rotor windings Phase 1 The branches being connected in parallel, when the two branches are in the stator Equivalent to a antipodal magnetic field The branch is connected in series with a segment of resistor.

Description

Harmonic self-starting permanent magnet synchronous motor Technical Field The invention relates to the technical field of motors, in particular to a harmonic self-starting permanent magnet synchronous motor. Background The permanent magnet synchronous motor has the advantages of high efficiency, high power factor, stable operation and the like, and is widely applied to the fields of industrial transmission, new energy automobiles, household appliances and the like. However, the conventional permanent magnet synchronous motor has the problem of difficult starting, and particularly under a heavy-load starting scene, the starting torque is insufficient, the starting current is overlarge, and the actual working condition requirements are difficult to meet. The prior art is mainly characterized in that a slip ring and an electric brush are additionally arranged on the rotor side and are connected in series with a starting resistor, starting torque is improved and starting current is restrained by increasing the rotor resistor, however, the slip ring and the electric brush not only can increase the structural complexity of the motor and improve maintenance cost, but also are easy to cause faults such as abrasion, poor contact and the like, and the reliability of the operation of the motor is reduced, meanwhile, a complex control circuit is required for cutting and throwing of the additional starting resistor, the overall cost and the failure rate of the system are further improved, the traditional starting scheme adopting a brushless structure is adopted, but the scheme often has the defect that starting performance and operation efficiency are difficult to be compatible, extra loss is generated when the starting winding normally operates, the operation efficiency of the motor is reduced, and if the starting winding is cut off, a switching device is required, the structure of the motor cannot be fundamentally simplified. Disclosure of Invention The invention provides a harmonic self-starting permanent magnet synchronous motor, which aims to solve the technical problems of the background technology. The invention adopts the following technical scheme that the harmonic self-starting permanent magnet synchronous motor comprises a stator and a rotor, wherein two sets of relatively independent windings, namely a starting winding and an auxiliary winding, are arranged on the stator, and a set of permanent magnet and two sets of rotor windings are arranged on the rotor; the starting winding and the auxiliary winding all generate pole pair number of Is used for simultaneously generating the fundamental magnetic field of the pole pair number as、A harmonic magnetic field with the same rotation direction as the fundamental magnetic field; the two sets of rotor windings are all according to Counter electrodeThe phase normal phase band is respectively provided with a first rotor winding and a second rotor winding, and the coil pitch of the first rotor winding is as followsThe whole pole distance or short pole distance corresponding to the counter pole is distributed, and the pitch of the second rotor winding coil is according to2 Times of the number of slots of the whole pole distance corresponding to the antipodal harmonic wave, the first rotor windingPhase 1Branch, and the first of the second rotor windingsPhase 1The branches being connected in parallel, when the two branches are in the statorIn the case of fundamental magnetic field, the phase difference of the central axes of the magnetic fields induced by the two branches is aboutElectric angle, and second rotor windingPhase 1Branches, in the form of statorsWhen the counter-pole magnetic field is generated, the vector synthesis value of the induced electromotive force is equal to zero; the rotor is provided with a set of pole pairs Is a permanent magnet of a magnetic core. Preferably, when the motor is started, a starting winding on the stator is connected to a power grid, and the starting winding generates pole pair number ofIs the fundamental magnetic field and the pole pair number is、And (2) harmonic magnetic field of、、The direction of rotation of the counter-pole magnetic fields is the same. Preferably, when the auxiliary winding on the motor stator is connected to the power grid, the auxiliary winding generates a pole pair number ofIs the fundamental magnetic field and the pole pair number is、And (2) harmonic magnetic field of、、The direction of rotation of the counter-pole magnetic fields is the same. Preferably, the saidThe said,。 Preferably, the motor start winding is generatedGenerated by opposite magnetic field and auxiliary windingAntipodal magnetic field, at phase differenceThe electrical angles, i.e. the spatially in-phase inside the motor, the magnetic fields are superimposed on each other. Preferably, the motor start winding is generated、Opposite-pole harmonic magnetic field and auxiliary winding、Antipodal harmonic magnetic fields differing in phase respect