A dual-winding stator and a self-starting synchronous reluctance motor

Abstract

The present disclosure provides a dual-winding stator and a self-starting synchronous reluctance motor. The dual-winding stator includes: a stator core, a starting winding, and a running winding. The stator core includes a plurality of stator teeth distributed in a circumferential direction. The starting winding and the running winding are respectively wound around the stator teeth. Moreover, a stator slot is formed between two adjacent stator teeth, and the starting winding and the running winding are both located in the stator slot. In the cross-section of the stator core, the area of the stator slot is S, the cross-sectional area of the starting winding located in the stator slot is S Z1 , and the cross-sectional area of the running winding located in the same stator slot is S Z2 , and there is S Z1 < S Z2 ; the number of turns of the starting winding located in the stator slot is N Z1 , and the number of turns of the running winding located in the stator slot is N Z2 , and there is N Z1 < N Z2 . According to the present disclosure, the starting ability can be enhanced and the operating efficiency of the motor can be ensured at the same time.

Description

Technical Field

[0001] The present disclosure relates to the technical field of motors, and particularly to a dual-winding stator and a self-starting synchronous reluctance motor. Background Art

[0002] The self-starting synchronous reluctance motor combines the characteristics of an asynchronous motor and a synchronous reluctance motor, and has the following basic features:

[0003] Axial air slots are formed in the rotor. The air slots are called magnetic barrier slots, and the iron core part formed between every two layers of magnetic barrier slots is called a magnetic conduction channel;

[0004] All or part of the magnetic barrier slots are filled with a conductive non-magnetic material (such as aluminum), which is called a bar;

[0005] There are end rings at both axial ends of the rotor. The material of the end rings is the same as that of the bars. The end rings at both ends of the rotor are connected to all or part of the bars in the rotor slots to form a short-circuit loop;

[0006] Two symmetry axes D and Q are formed for each pole of the rotor. The axis approximately parallel to the magnetic conduction channel is called the D axis, and the axis approximately perpendicular to the magnetic conduction channel is called the Q axis;

[0007] The self-starting synchronous reluctance motor combines the advantages of an asynchronous motor that can be directly started without a frequency converter and has no permanent magnets on the rotor, with high reliability, and a synchronous reluctance motor that can operate stably at synchronous speed, high efficiency, and high power density. In the industrial field, it breaks through the IE4 energy efficiency of fixed-frequency motors while having a lower cost.

[0008] The self-starting synchronous reluctance motor is different from an asynchronous motor. The starting process not only has a starting stage but also a pulling-in stage. When pulling in, the rotor approaches the synchronous speed, that is, the slip rate between the stator and the rotor approaches 0. At this time, the main torque during the starting process, the asynchronous torque, is very small. Therefore, it is difficult to pull in;

[0009] The fewer the number of winding turns, the larger the starting current, the larger the starting torque, and the easier it is to start. However, the running current is also large, resulting in a decrease in efficiency.

[0010] Due to the technical problems in the prior art that the self-starting synchronous reluctance motor has difficulties in starting and the motor efficiency cannot be improved simultaneously, the present disclosure has studied and designed a dual-winding stator and a self-starting synchronous reluctance motor.

[0011] Disclosed content

[0012] Therefore, the technical problem to be solved by the present disclosure is to overcome the defect that the self-starting synchronous reluctance motor in the prior art has difficulties in starting and the motor efficiency cannot be improved simultaneously, so as to provide a dual-winding stator and a self-starting synchronous reluctance motor.

[0013] To solve the above problems, the present disclosure provides a dual-winding stator, which includes:

[0014] A stator core, a starting winding, and a running winding. The stator core includes a plurality of stator teeth distributed in the circumferential direction. The starting winding and the running winding are respectively wound around the stator teeth; and a stator slot is formed between two adjacent stator teeth. Both the starting winding and the running winding are located in the stator slot;

[0015] In the cross-section of the stator core, the area of the stator slot is S, the cross-sectional area of the starting winding located in the stator slot is S Z1 , and the cross-sectional area of the running winding located in the same stator slot is S Z2 , and there is S Z1 < S Z2 ;

[0016] The number of turns of the starting winding located in the stator slot is N Z1 , and the number of turns of the running winding located in the stator slot is N Z2 , and there is N Z1 < N Z2 .

[0017] In some embodiments, the ratio of the number of turns of the starting winding to the running winding is greater than the ratio of their cross-sectional areas;

[0018]

[0019] In some embodiments, the number of stator slots is n, the starting winding is n groups, and the running winding is also n groups, where n is an integer ≥ 1.

[0020] In some embodiments, the starting winding includes a first lead-in portion, which is the position where the starting winding starts winding on the stator slot. The running winding includes a second lead-in portion, which is the position where the running winding starts winding on the stator slot. The first lead-in portion and the second lead-in portion are located in the same stator slot.

[0021] In some embodiments, the starting winding includes a first lead-in portion, which is the position where the starting winding starts winding on the stator slot. The running winding includes a second lead-in portion, which is the position where the running winding starts winding on the stator slot. The stator slot where the first lead-in portion is located is offset by N S1 slots in the circumferential direction from the stator slot where the second lead-in portion is located, and there is: where p is the number of pole pairs of the dual-winding stator, Ns is the number of stator slots, N S1Take an integer, and the range of A is (0, 0.5).

[0022] In some embodiments, it further includes a switch and a power supply. The starting winding includes a first lead-out part, and the running winding includes a second lead-out part. The first lead-out part is electrically connected to the switch. The switch can be opened when the motor starts, so that the second lead-out part of the starting winding and the running winding can be connected in parallel to the power supply. After the motor reaches the synchronous speed, the switch can be disconnected.

[0023] In some embodiments, the switch is a circuit switch, a relay or a control circuit.

[0024] In some embodiments, in the axial direction of the stator core, the running winding has a double-layer or multi-layer structure, and the starting winding has a double-layer or multi-layer structure.

[0025] In some embodiments, the winding position of the starting winding on the stator tooth is located radially outside the winding position of the running winding on the stator tooth; and / or,

[0026] The running winding works or does not work during the starting stage.

[0027] The present disclosure also provides a self-starting synchronous reluctance motor, which includes the aforementioned double-winding stator.

[0028] A double-winding stator and a self-starting synchronous reluctance motor provided by the present disclosure have the following beneficial effects:

[0029] 1. The stator of the motor in the present disclosure adopts a double-layer winding. One layer of the winding has fewer turns for starting, and the other layer has more turns for running; the starting winding has fewer turns, a thinner wire diameter, and occupies less slot area, while the running winding has more turns and occupies most of the slot area; thus, both the starting ability is enhanced and the motor running efficiency is ensured.

[0030] 2. The present disclosure also makes the ratio of the number of turns of the starting winding to the number of turns of the running winding greater than the ratio of their cross-sectional areas It can avoid occupying too much space in the slot, increase the cross-sectional area of the running winding to reduce the running resistance, and improve the energy efficiency;

[0031] 3. The present disclosure also makes the starting winding and the running winding aligned or offset by N S1 slots in the stator slots;

[0032] And a switch is used. When in use, the switch is turned on, and the output wires of the starting winding and the running winding are connected in parallel to the power supply, which can maximize the starting current of the motor during the starting process, thereby improving the starting ability; by disconnecting the starting winding switch after the motor reaches the synchronous speed, the starting winding can be stopped from working during the stable operation stage, thereby reducing losses and improving energy efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the starting winding, the running winding and their cross-sectional areas of the present disclosure;

[0034] Figure 2 It is a schematic diagram of the position relationship between the starting winding and the running winding of the present disclosure;

[0035] Figure 3 It is a circuit diagram for using the double winding of the motor disclosed in the present invention;

[0036] Figure 4 A comparison chart of the starting capabilities of the dual-winding motor disclosed herein (with starting winding added);

[0037] Figure 5 It is the starting current waveform diagram of the present invention (starting winding and running winding offset angle).

[0038] The reference numerals are as follows:

[0039] 1. Stator core; 11. Stator teeth; 12. Stator slots; 2. Starting winding; 21. First incoming line part; 22. First outgoing line part; 3. Running winding; 31. Second incoming line part; 32. Second outgoing line part; 4. Switch; 5. Power supply. DETAILED DESCRIPTION

[0040] like Figures 1 - 5 As shown, the present disclosure provides a double-winding stator, which includes:

[0041] A stator core 1, a starting winding 2 and a running winding 3, wherein the stator core 1 comprises a plurality of stator teeth 11 distributed along a circumferential direction, the starting winding 2 and the running winding 3 are respectively wound on the stator teeth 11; and a stator slot 12 is formed between two adjacent stator teeth 11, and the starting winding 2 and the running winding 3 are both located in the stator slot 12;

[0042] In the cross section of the stator core 1, the area of ​​the stator slot 12 is S, and the cross section area of ​​the starting winding 2 located in the stator slot 12 is S. Z1 The cross-sectional area of ​​the running winding 3 located in the stator slot 12 is S Z2 , and S Z1 <S Z2 ;

[0043] The number of turns of the starting winding 2 located in the stator slot 12 is N Z1 The number of turns of the running winding 3 located in the stator slot 12 is N Z2 and there is N Z1 <N Z2 .

[0044] The stator of the motor disclosed in the present disclosure adopts a double-layer winding, where one layer of the winding has fewer turns for starting and the other layer has more turns for running; the starting winding has fewer turns and a thinner wire diameter, occupying less slot area, and the running winding has more turns, occupying most of the slot area; thus, both the starting ability is enhanced and the operating efficiency of the motor is ensured.

[0045] In some embodiments, the ratio of the number of turns of the starting winding 2 to the number of turns of the running winding 3 is greater than the ratio of their cross-sectional areas;

[0046]

[0047] The present disclosure also enables avoiding occupying too much space in the slot, increasing the cross-sectional area of the running winding to reduce the running resistance, and improving the energy efficiency by making the ratio of the number of turns of the starting winding to the number of turns of the running winding greater than the ratio of their cross-sectional areas and being able to avoid occupying too much space in the slot, increasing the cross-sectional area of the running winding to reduce the running resistance, and improving the energy efficiency.

[0048] 1. The double-layer winding of the present disclosure is divided into a starting winding and a running winding;

[0049] 2. The starting winding has fewer turns and a thinner wire diameter, occupying only a very small part of the slot area;

[0050] 3. The running winding has more turns, occupying most of the slot area;

[0051] 4. The starting winding and the running winding are connected in parallel to the power grid during the starting stage, and a switch is connected in series in front of the starting winding, which is disconnected after the motor is synchronized;

[0052] 5. The starting winding and the running winding are staggered by a certain phase in space, that is, the starting slots where they are wound in the stator are different.

[0053] 1. The starting winding of the present disclosure refers to: the stator winding that only works during the starting stage of the motor;

[0054] 2. The running winding of the present disclosure refers to: the stator winding that plays a role during both the starting stage and the running stage;

[0055] 3. The stator slot area of the present disclosure refers to: the cross-sectional area in the stator slot for placing the winding;

[0056] 4. The cross-sectional area of the starting winding of the present disclosure refers to: the cross-sectional area occupied by the starting winding in each slot;

[0057] 5. The cross-sectional area of the running winding of the present disclosure refers to: the cross-sectional area occupied by the running winding in each slot;

[0058] 6. The number of turns in the present disclosure refers to the number of loops that each winding coil is repeatedly wound;

[0059] 7. The starting slot in the present disclosure refers to the starting slot where the windings are inserted;

[0060] 8. The starting inertia multiple in the present disclosure refers to the ratio of the load inertia carried by the motor during starting to the inertia of the motor itself.

[0061] In some embodiments, the number of stator slots 12 is n, the number of starting windings 2 is n groups, and the number of running windings is also n groups, where n is an integer greater than or equal to 1.

[0062] Windings 6 wound from enameled wires are inserted into the stator slots; the windings are divided into 2 groups or 2n groups, where n is an integer greater than or equal to 1. Among them, n groups of windings are starting windings 2, and the other n groups of windings are running windings 3.

[0063] In some embodiments, the starting winding 2 includes a first lead-in portion 21, which is the position where the starting winding 2 starts winding on the stator slot 12. The running winding 3 includes a second lead-in portion 31, which is the position where the running winding 3 starts winding on the stator slot 12. The first lead-in portion 21 and the second lead-in portion 31 are located in the same stator slot 12.

[0064] In some embodiments, the starting winding 2 includes a first lead-in portion 21, which is the position where the starting winding 2 starts winding on the stator slot 12. The running winding 3 includes a second lead-in portion 31, which is the position where the running winding 3 starts winding on the stator slot 12. The stator slot where the first lead-in portion 21 is located is offset by N S1 slots in the circumferential direction from the stator slot where the second lead-in portion 31 is located, and there is: where p is the number of pole pairs of the double-winding stator, Ns is the number of stator slots, N S1 is an integer, and the range of A is (0, 0.5).

[0065] The present disclosure also aligns or offsets the starting winding and the running winding by N S1 slots in the stator slots;

[0066] And a switch is adopted. When in use, the switch is turned on, and the outgoing line parts of the starting winding and the running winding are connected in parallel to the power supply, which can make the starting current of the motor the largest during the starting process, thereby improving the starting ability.

[0067] In some embodiments, it further includes a switch 4 and a power supply 5. The starting winding 2 includes a first lead-out portion 22, and the running winding 3 includes a second lead-out portion 32. The first lead-out portion 22 is electrically connected to the switch 4. The switch 4 can be opened during motor starting, so that the second lead-out portion 32 of the starting winding 2 and the running winding 3 can be connected in parallel to the power supply 5. After the motor reaches the synchronous speed, the switch 4 can be disconnected. Connecting the lead-out parts of the starting winding and the running winding in parallel to the power supply can make the starting current of the motor the largest during the starting process, thereby improving the starting ability; by disconnecting the starting winding switch after the motor reaches the synchronous speed, it can be ensured that the starting winding does not work during the stable operation stage, thereby reducing losses and improving energy efficiency.

[0068] Windings wound by enameled wires are embedded in the stator slots; the windings are divided into 2 groups or 2n groups, where n is an integer greater than or equal to 1. Among them, n groups of windings are the starting winding 2, and the other n groups of windings are the running winding 3;

[0069] The total area of each stator slot is S, the cross-sectional area of the starting winding in each slot is S Z1 , and the cross-sectional area of the running winding in each slot is S Z2 ;

[0070] The number of turns of the starting winding is N Z1 , and the number of turns of the running winding is N Z2 , and the ratio of the number of turns of the starting winding to the running winding is greater than the ratio of their cross-sectional areas;

[0071]

[0072] The above three points stipulate that the starting winding has fewer turns and is used for starting, which can enhance the starting ability; the turn ratio is greater than the cross-sectional area ratio, avoiding occupying too much space in the slot, increasing the cross-sectional area of the running winding and reducing the running resistance, thereby improving energy efficiency;

[0073] The starting winding and the running winding are aligned or offset by N S1 slots in the stator slots; N S1 takes an integer, and the range of A is (0, 0.5);

[0074] The lead-out part of the starting winding is connected to a protection switch. When in use, the switch is opened, and the lead-out parts of the starting winding and the running winding are connected in parallel to the power supply. After the motor reaches the synchronous speed, the starting winding switch is disconnected;

[0075] The above two points make the starting current of the motor the largest during the starting process, thereby improving the starting ability; the starting winding does not work during the stable operation stage, thereby reducing losses and improving energy efficiency.

[0076] In some embodiments, the switch 4 is a circuit switch, a relay or a control circuit.

[0077] In some embodiments, in the axial direction of the stator core 1, the running winding 3 has a double-layer or multi-layer structure, and the starting winding 2 has a double-layer or multi-layer structure. The double-layer or multi-layer starting winding structure can improve the starting ability, and the double-layer or multi-layer running winding can enhance the running current, increase the running torque, and improve the motor capacity and energy efficiency.

[0078] In some embodiments, the winding position of the starting winding 2 on the stator tooth 11 is located radially outside the winding position of the running winding 3 on the stator tooth 11; and / or,

[0079] The running winding 3 works or does not work during the starting stage. Preferably, the running winding does not work during the starting stage, which can increase the current of the starting winding, enhance the starting torque, and improve the starting ability.

[0080] The present disclosure also provides a self-starting synchronous reluctance motor, which includes the double-winding stator described in any one of the preceding items.

[0081] The foregoing is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure. The foregoing is only a preferred implementation manner of the present disclosure. It should be noted that for those of ordinary skill in the art, several improvements and variations can be made without departing from the technical principle of the present disclosure, and these improvements and variations should also be regarded as the protection scope of the present disclosure.

Claims

1. A dual-winding stator of a self-starting synchronous reluctance motor, characterized in that: It includes: A stator core (1), a starting winding (2) and a running winding (3). The stator core (1) includes a plurality of stator teeth (11) distributed circumferentially. The starting winding (2) and the running winding (3) are respectively wound around the stator teeth (11); and a stator slot (12) is formed between two adjacent stator teeth (11). Both the starting winding (2) and the running winding (3) are located in the stator slot (12); In the cross-section of the stator core (1), the area of the stator slot (12) is S, and the cross-sectional area of the starting winding (2) located in the stator slot (12) is S Z1 , and the cross-sectional area of the running winding (3) located in the stator slot (12) is S Z2 , and there is S Z1 < S Z2 ; The number of turns of the starting winding (2) located in the stator slot (12) is N Z1 , the number of turns of the running winding (3) located in the stator slot (12) is N Z2 , and there is N Z1 <N Z2 ; The starting winding (2) includes a first wire-in portion (21), and the first wire-in portion (21) is the position where the starting winding (2) starts winding on the stator slot (12). The running winding (3) includes a second wire-in portion (31), and the second wire-in portion (31) is the position where the running winding (3) starts winding on the stator slot (12). The stator slot where the first wire-in portion (21) is located is offset by N slots in the circumferential direction from the stator slot where the second wire-in portion (31) is located. S1 where: where p is the number of pole pairs of the double-winding stator, Ns is the number of stator slots, and N S1 is an integer, and the range of A is (0, 0.5); The number of the stator slots (12) is n, the starting winding (2) is n groups, and the running winding is also n groups, where n is an integer greater than or equal to 1.

2. The dual-winding stator of the self-starting synchronous reluctance motor according to claim 1, characterized in that: The ratio of the number of turns of the starting winding (2) to the running winding (3) is greater than the ratio of their cross-sectional areas; 3. The dual-winding stator of the self-starting synchronous reluctance motor according to claim 1, characterized in that: It further includes a switch (4) and a power supply (5). The starting winding (2) includes a first lead-out part (22), the running winding (3) includes a second lead-out part (32), the first lead-out part (22) is electrically connected to the switch (4), and the switch (4) can be opened during motor starting so that the second lead-out part (32) of the starting winding (2) and the running winding (3) can be connected in parallel to the power supply (5), and the switch (4) can be disconnected after the motor reaches synchronous speed.

4. The dual-winding stator of the self-starting synchronous reluctance motor according to claim 1, characterized in that: The switch (4) is a circuit switch, a relay or a control circuit.

5. The dual-winding stator of the self-starting synchronous reluctance motor according to claim 1, characterized in that: In the axial direction of the stator core (1), the running winding (3) is of a double-layer or multi-layer structure, and the starting winding (2) is of a double-layer or multi-layer structure.

6. The dual-winding stator of the self-starting synchronous reluctance motor according to claim 1, characterized in that: The winding position of the starting winding (2) on the stator teeth (11) is located radially outside the winding position of the running winding (3) on the stator teeth (11); and / or, The running winding (3) works or does not work during the starting stage.

7. A self-starting synchronous reluctance motor, characterized in that: It includes the dual-winding stator of the self-starting synchronous reluctance motor according to any one of claims 1-6.

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