Squirrel cage adjustable magnetic ring induction motor

Abstract

The invention relates to the field of induction motors, and provides a squirrel-cage adjustable magnetic ring induction motor, which comprises a stator, a squirrel-cage adjustable magnetic ring and a double-squirrel-cage rotor, the stator is provided with a stator slot and an armature winding and is used for cooperating with a rotating magnetic field to generate electromagnetic torque; the mouse cage magnetism adjusting ring comprises a plurality of single mouse cage rings and a magnetism adjusting ring iron core; the magnetic field adjusting ring iron core is provided with a magnetic field adjusting ring iron core groove, and the mouse cage magnetic field adjusting ring is embedded in the magnetic field adjusting ring iron core through the magnetic field adjusting ring iron core groove and used for inducing current and converting the number of pole pairs of a magnetic field through magnetic field modulation. The double-squirrel-cage rotor comprises an inner squirrel cage and an outer squirrel cage, the inner squirrel cage is arranged on the innermost layer of the motor and is composed of an inner-layer rotor iron core and squirrel cage strips, and the outer squirrel cage is arranged between the squirrel cage magnetic adjusting ring and the inner squirrel cage, is composed of an outer-layer rotor iron core and squirrel cage strips and is used for carrying out back electromotive force and current induction on the modulated magnetic field; therefore, electromechanical energy conversion is completed. According to the invention, through the squirrel-cage adjustable magnetic ring and the double-squirrel-cage rotor structure, larger output torque and power factor are provided.

Description

Technical Field

[0001] The invention belongs to the field of induction motors, and in particular relates to a squirrel cage magnetic ring induction motor. Background Art

[0002] The induction motor is a widely used electric motor. Its working principle mainly relies on the stator to generate a rotating magnetic field and induce an electromotive force in the rotor, thereby generating torque to drive the rotor to rotate. However, traditional induction motors have unstable torque after starting and have starting problems. In order to solve the shortcomings of traditional induction motors, squirrel cage induction motors are widely used. They mainly adopt a double squirrel cage rotor structure and use the skin effect of the double squirrel cage to reduce the starting current of the motor, thereby effectively improving the starting performance of the motor.

[0003] Although squirrel cage induction motors have many advantages, they still have limitations in increasing output torque and improving power factor. These include the fixed number of magnetic field pole pairs leading to limitations in output torque and power factor; the limitations of the rotor structure resulting in a fixed layout of the conductor bars and cage bars that limits the distribution of the induced current; and the limitations of the modulation block leading to a limited adjustment range. Summary of the invention

[0004] In view of the above-mentioned defects of the prior art, the present invention proposes a squirrel cage magnetic ring induction motor, and the technical solution designed by the present invention includes:

[0005] Stator, squirrel cage magnetic ring and double squirrel cage rotor;

[0006] The stator is provided with stator slots, and the stator slots are provided with armature windings for inputting alternating current and rotating the magnetic field through the two polarity ends of the alternating current;

[0007] The squirrel cage magnetic adjustment ring comprises a plurality of single squirrel cage rings and a magnetic adjustment ring core;

[0008] The magnetic tuning ring core is provided with a magnetic tuning ring core slot, and the squirrel cage magnetic tuning ring is embedded in the magnetic tuning ring core through the magnetic tuning ring core slot, and is used for inducing current and converting the magnetic field pole logarithm through magnetic field modulation;

[0009] The double-cage rotor comprises an inner cage and an outer cage. The inner cage is arranged at the innermost layer of the motor and is composed of an inner rotor core and cage bars. The outer cage is arranged between the cage magnetic tuning ring and the inner cage and is composed of an outer rotor core and cage bars. The outer cage is used to perform back electromotive force and current induction on the magnetic field after magnetic field modulation, thereby completing electromechanical energy conversion.

[0010] Preferably, the squirrel cage bar is a shaped bare copper bar

[0011] Preferably, the single squirrel cage ring is formed by welding the ends of n squirrel cage bars through welding rings, n>1, and the number of core slots of the magnetic tuning ring is p fn, p f is the number of cage rings.

[0012] Preferably, the stator magnetic field pole pair number p of the stator s Adjust the number of magnetic ring pole pairs p by squirrel cage f The magnetic modulation effect induces the corresponding p in the inner air gap e The magnetic field of the pole pair number satisfies the relationship p f =p e +p s .

[0013] Preferably, the inner cage is made of cast copper, and the outer cage is made of cast aluminum.

[0014] Preferably, both the inner rotor core and the outer rotor core are provided with rotor slots.

[0015] Preferably, the number of slots of the inner rotor core is the same as the number of slots of the outer rotor core, the slot spacing of the inner rotor core is equal to the slot spacing of the outer rotor core, and the positions of the rotor slots of the inner rotor core correspond one-to-one with the rotor slots of the outer rotor core.

[0016] Preferably, the slot volume of the inner rotor core is greater than the slot volume of the outer rotor core.

[0017] Preferably, the inner squirrel cage comprises squirrel cage bars whose ends are welded through welding rings, and the squirrel cage bars are built into rotor slots of an inner rotor core and welded to the welding rings; the outer squirrel cage comprises squirrel cage bars whose ends are welded through welding rings, and the squirrel cage bars are built into rotor slots of an outer rotor core and welded to the welding rings.

[0018] Preferably, the inner squirrel cage includes an inner rotor core with a magnetic bridge in the middle; the outer squirrel cage includes an outer rotor core with a magnetic bridge in the middle, and the thickness of the magnetic bridge is between 0.5-2 mm.

[0019] Beneficial effects:

[0020] 1. The squirrel cage magnetic tuning ring used in the present invention is composed of multiple squirrel cage ring structures acting as the modulation unit of the modulation motor. The squirrel cage ring is embedded with the iron core to realize the conversion of the number of magnetic field poles. Compared with the traditional magnetic tuning block modulation, it can improve the uneven distribution of the air gap and reduce the leakage magnetic field, thereby improving the torque output level and power factor of the motor;

[0021] 2. The double-cage rotor structure adopted in the present invention, on the one hand, can induce induced electromotive force and current by inducing the magnetic field modulated by the magnetic tuning ring in the double-cage, and the harmonics are rich. Various harmonics can induce back electromotive force and current. The useful harmonic content is relatively large and can be well utilized. On the other hand, the double-cage structure can improve the starting performance of the modulated motor, make the motor start-up torque stable, and can also improve the reliability and stability of the motor to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of a squirrel cage magnetic ring induction motor according to a preferred embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of a squirrel cage magnetic tuning ring in a preferred embodiment of the present invention;

[0024] Figure 3 Schematic diagram of different numbers of copper bars in a single squirrel cage ring of a preferred embodiment of the present invention;

[0025] Figure 4 1 is a schematic diagram of the motor topology of a single squirrel cage rotor according to a preferred embodiment of the present invention;

[0026] Figure 5 It is a schematic diagram of the motor topology of a wound rotor according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are described in detail below. The following embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0028] The present invention designs a squirrel cage magnetic ring induction motor. On the one hand, the squirrel cage ring structure is used to realize the conversion of the magnetic field pole pairs of the motor, optimize the disadvantages of the conventional modulation block, thereby providing a larger output torque and power factor. On the other hand, the use of a double squirrel cage rotor can reduce the starting current of the motor and improve the starting performance of the motor. In addition, due to the squirrel cage rotor structure, the magnetic field harmonics modulated to the squirrel cage rotor are very rich, and various harmonics can induce back electromotive force and current in them. There are many useful harmonics, such as Figure 1-3 As shown, the technical solution specifically includes:

[0029] Stator 1, squirrel cage magnetic ring 2 and double squirrel cage rotor 3;

[0030] The stator 1 is provided with stator slots, and the stator slots are provided with armature windings 4 for inputting alternating current and rotating the magnetic field through the two polarity ends of the alternating current;

[0031] The squirrel cage magnetic adjustment ring 2 comprises two or more single squirrel cage rings and a magnetic adjustment ring core 5;

[0032] The magnetic tuning ring core 5 is provided with a magnetic tuning ring core slot, and the squirrel cage magnetic tuning ring 2 is embedded in the magnetic tuning ring core 5 through the magnetic tuning ring core slot, and is used for inducing current and converting the magnetic field pole logarithm through magnetic field modulation;

[0033] The double-cage rotor 3 includes an inner cage 6 and an outer cage 7. The inner cage 6 is arranged at the innermost layer of the motor and is composed of an inner rotor core 8 and cage bars 9. The outer cage 7 is arranged between the cage magnetic tuning ring 2 and the inner cage 6 and is composed of an outer rotor core 10 and cage bars 9. It is used to perform back electromotive force and current induction on the magnetic field after magnetic field modulation, thereby completing electromechanical energy conversion.

[0034] Specifically, an armature winding 4 is provided in the stator slots for inputting alternating current and rotating the magnetic field through the two polarity ends of the alternating current, thereby generating electromagnetic torque.

[0035] Preferably, the squirrel cage bar 9 is a shaped bare copper bar

[0036] Preferably, a single cage ring is formed by welding the ends of n cage bars 9 through welding rings, n>1, and the number of magnetic core slots of the magnetic ring is p. f n, p f is the number of cage rings.

[0037] Preferably, the number of stator magnetic field pole pairs p of the stator 1 is s Adjust the number of magnetic ring pole pairs p by squirrel cage f The magnetic modulation effect induces the corresponding p in the inner air gap e The magnetic field of the pole pair number satisfies the relationship p f =p e +p s .

[0038] Specifically, the number of stator magnetic field pole pairs p s The stator generates a rotating magnetic field, and the number of magnetic field poles is called p e ; Number of pole pairs of squirrel cage magnetic ring p f The squirrel cage magnetic ring modulates the magnetic field, so that the pole pair number of the magnetic field is converted, and the pole pair number from the stator to the inner air gap becomes p e .

[0039] Preferably, the inner cage 6 is made of cast copper, and the outer cage 7 is made of cast aluminum.

[0040] Preferably, both the inner rotor core 8 and the outer rotor core 10 are provided with rotor slots.

[0041] Preferably, the number of slots of the inner rotor core 8 is the same as the number of slots of the outer rotor core 10, the slot spacing of the inner rotor core 8 is equal to the slot spacing of the outer rotor core 10, and the positions of the rotor slots of the inner rotor core 8 and the rotor slots of the outer rotor core 10 correspond one to one.

[0042] Preferably, the slot volume of the inner rotor core 8 is greater than the slot volume of the outer rotor core 10 .

[0043] Preferably, the inner squirrel cage 6 comprises the ends of the squirrel cage bars 9 welded through a welding ring, the squirrel cage bars 9 are built into the rotor slots of the inner rotor core 8 and welded to the welding ring; the outer squirrel cage 7 comprises the ends of the squirrel cage bars 9 welded through a welding ring, the squirrel cage bars 9 are built into the rotor slots of the outer rotor core 10 and welded to the welding ring.

[0044] Preferably, the inner cage 6 includes an inner rotor core 8 with a magnetic bridge 11 in the middle; the outer cage 7 includes an outer rotor core 10 with a magnetic bridge 11 in the middle, and the thickness of the magnetic bridge is between 0.5-2 mm.

[0045] Specifically, Figure 4-5 As shown, the double-cage rotor can have different structural topologies, including a single-cage rotor, a wound rotor, etc. Correspondingly, induction motors with different topological structures can be formed, and different rotor types can produce differences in performance.

[0046] The preferred specific embodiments of the present invention are described in detail above. It should be understood that ordinary technicians in the field can make many modifications and changes based on the concept of the present invention without creative work. Therefore, all technical solutions that can be obtained by technicians in the technical field based on the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A squirrel cage magnetic ring induction motor, characterized in that: include: Stator, squirrel cage magnetic ring and double squirrel cage rotor; The stator is provided with stator slots, and the stator slots are provided with armature windings for inputting alternating current and rotating the magnetic field through the two polarity ends of the alternating current; The squirrel cage magnetic adjustment ring comprises a plurality of single squirrel cage rings and a magnetic adjustment ring core; The magnetic tuning ring core is provided with a magnetic tuning ring core slot, and the squirrel cage magnetic tuning ring is embedded in the magnetic tuning ring core through the magnetic tuning ring core slot, and is used for inducing current and converting the magnetic field pole logarithm through magnetic field modulation; The double-cage rotor comprises an inner cage and an outer cage. The inner cage is arranged at the innermost layer of the motor and is composed of an inner rotor core and cage bars. The outer cage is arranged between the cage magnetic tuning ring and the inner cage and is composed of an outer rotor core and cage bars. The outer cage is used to perform back electromotive force and current induction on the magnetic field after magnetic field modulation, thereby completing electromechanical energy conversion.

2. The squirrel cage magnetic ring induction motor according to claim 1, characterized in that: The squirrel cage bars are formed bare copper bars.

3. The squirrel cage magnetic ring induction motor according to claim 2, characterized in that: The single cage ring is formed by welding the ends of n cage bars through welding rings, n>1, and the number of core slots of the magnetic tuning ring is p. f n, p f is the number of cage rings.

4. The squirrel cage magnetic ring induction motor according to claim 3, characterized in that: The stator magnetic field pole pair number p of the stator s Adjust the number of magnetic ring pole pairs p by squirrel cage f The magnetic modulation effect induces the corresponding p in the inner air gap e The magnetic field of the pole pair number satisfies the relationship p f =p e +p s .

5. The squirrel cage magnetic ring induction motor according to claim 1, characterized in that: The inner squirrel cage is made of cast copper, and the outer squirrel cage is made of cast aluminum.

6. The squirrel cage magnetic ring induction motor according to claim 1, characterized in that: Both the inner rotor core and the outer rotor core are provided with rotor slots.

7. The squirrel cage magnetic ring induction motor according to claim 6, characterized in that: The number of slots of the inner rotor core is the same as that of the outer rotor core, the slot spacing of the inner rotor core is equal to that of the outer rotor core, and the positions of the rotor slots of the inner rotor core correspond to those of the rotor slots of the outer rotor core.

8. The squirrel cage magnetic ring induction motor according to claim 6, characterized in that: The slot volume of the inner rotor core is greater than the slot volume of the outer rotor core.

9. The squirrel cage magnetic ring induction motor according to claim 2, characterized in that: The inner squirrel cage comprises squirrel cage bars whose ends are welded through welding rings, and the squirrel cage bars are built into rotor slots of an inner rotor core and welded to the welding rings; the outer squirrel cage comprises squirrel cage bars whose ends are welded through welding rings, and the squirrel cage bars are built into rotor slots of an outer rotor core and welded to the welding rings.

10. The squirrel cage magnetic ring induction motor according to claim 1, characterized in that: The inner squirrel cage includes an inner rotor core with a magnetic bridge in the middle; the outer squirrel cage includes an outer rotor core with a magnetic bridge in the middle, and the thickness of the magnetic bridge is between 0.5-2mm.

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