Synchronous motor and compressor
阅读说明：本技术 同步电机和压缩机 (Synchronous motor and compressor ) 是由 邱小华 徐飞 王玉龙 毛临书 乔正忠 于 2018-08-30 设计创作，主要内容包括：本发明提供了一种同步电机和压缩机。其中,同步电机包括：转子铁芯、定子铁芯和定子绕组。其中,通过合理设置定子槽的数量A1与转子铁芯的磁极的数量A2的关系、凸齿与线圈的绕线方式及定子绕组的连接方式,使得特定级槽配合的同步电机、凸齿与线圈的绕线方式及定子绕组的连接方式相结合有效地提升了反电势,抑制低次磁势谐波,由此提供高输出的电机,进而可改善电机的振动噪音。(The invention provides a synchronous motor and a compressor. Wherein, synchronous machine includes: rotor core, stator core and stator winding. The relation between the number A1 of the stator slots and the number A2 of the magnetic poles of the rotor core, the winding mode of the convex teeth and the coils and the connection mode of the stator windings are reasonably set, so that the combination of the synchronous motor matched with the specific grade slots, the winding mode of the convex teeth and the coils and the connection mode of the stator windings effectively improves the counter electromotive force, suppresses low-order magnetic potential harmonics, provides a high-output motor, and further improves the vibration noise of the motor.)
1. A synchronous machine, comprising:
a rotor core;
the stator core is arranged around the outer side of the rotor core and provided with an annular magnetic yoke and a plurality of convex teeth which are distributed at intervals along the circumferential direction of the central line of the annular magnetic yoke, the plurality of convex teeth comprise a plurality of tooth groups, each tooth group comprises a first tooth and a second tooth which are sequentially arranged along the rotation direction of the rotor core, and coils with the same phase are wound on the first tooth and the second tooth;
a stator winding, including a plurality of coils connected to each other, disposed in stator slots of the stator core and wound on the plurality of teeth, the plurality of coils including a first type of coil and a second type of coil, the stator winding being a three-phase stator winding, each phase of the stator winding having at least three joints, including a first joint, a second joint, and a third joint, the first joint and the second joint of each phase of the stator winding being disposed on the first type of coil, and the third joint of each phase of the stator winding being disposed on the second type of coil;
the first joint in the stator winding of each phase is connected with the second joint in the stator winding of the adjacent phase;
the second type coil in each phase of the stator winding is connected with the first type coil, and the third joint in each phase of the stator winding is connected with the corresponding three-phase power lead or the third joint in the stator winding of other phases;
wherein the number of stator slots A1 and the number of magnetic poles A2 of the rotor core satisfy: a2-a1 ═ 2.
2. Synchronous machine according to claim 1,
the A1 is 12, and the A2 is 14.
3. Synchronous machine according to claim 1,
the value range of the ratio N2/N1 of the number of turns N2 of the second type of coil to the number of turns N1 of the first type of coil is more than or equal to 0.49 and less than or equal to N2/N1 and less than or equal to 0.6;
the value range of the ratio d2/d1 of the bare wire diameter d2 of the second type of coil to the bare wire diameter d1 of the first type of coil is 1.1-1, d2/d 1-1.6.
4. Synchronous machine according to any of claims 1 to 3,
the value range of the ratio T2/T1 of the number T2 of the second type of coils to the number T1 of the first type of coils is 0.4-T2/T1-1.
5. Synchronous machine according to any of claims 1 to 3,
the winding direction of the coil on the first tooth is opposite to the winding direction of the coil on the second tooth.
6. Synchronous machine according to any of claims 1 to 3,
the rotor core includes: the rotor punching sheet comprises a rotor punching sheet and a slot, wherein a magnet is arranged in the slot;
the permanent magnets are arranged on any horizontal section of the rotor core in a straight line shape or a V-shaped shape, or the permanent magnets are tangential magnetizing magnets.
7. The synchronous machine of claim 6,
on any horizontal section of the rotor core, the sum of the lengths of the magnets under each pole is bm, the inner diameter of the stator core is Di, the number of pole pairs on the rotor core is P, wherein bm × 2P/(pi × Di) is more than or equal to 0.75 and less than or equal to 0.9.
8. The synchronous machine of claim 6,
when the permanent magnets are distributed in a V shape, the included angle range of the V shape is 90-130 degrees.
9. Synchronous machine according to any of claims 1 to 3,
the central angle corresponding to the pole crown of the rotor core of the synchronous motor is α 1, the pole pitch angle is α 2, wherein α 1/α 2 is more than or equal to 0.5.
10. Synchronous machine according to any of claims 1 to 3,
the ratio of the inner diameter Di of the stator core to the outer diameter Do thereof satisfies the following conditions: Di/Do is more than or equal to 0.52 and less than or equal to 0.57.
11. Synchronous machine according to any of claims 1 to 3,
the rated torque of the synchronous motor is T, the inner diameter of the stator core is Di, and the unit volume torque of the rotor of the synchronous motor is TPV, and the rated torque and the inner diameter of the stator core meet the following requirements:
5.18×10-7≤T×Di-3×TPV-1≤1.17×10-6，
5kN·m·m-3≤TPV≤45kN·m·m-3，
wherein the rated torque T is expressed in the unit of N.m, the inner diameter Di is expressed in the unit of mm, and the unit volume torque TPV is expressed in the unit of kN.m.m-3。
12. A compressor, characterized by comprising a synchronous electric machine according to any one of claims 1 to 11.
Technical Field
The invention relates to the technical field of compressors, in particular to a synchronous motor and a compressor.
Background
In the existing rotary direct-current frequency conversion compressor, in order to ensure the high efficiency of the motor, a permanent magnet built-in motor is generally adopted, each coil of a stator winding is wound on a stator tooth, and the number of magnetic poles of a magnet matched with a rotor core and the number of stator slots are 2 under the general condition: 3, the stator teeth and the rotor magnetic poles are distributed on the circumference at equal intervals. The disadvantage of this motor structure is the short distance of the coils, which results in a low winding factor, due to the flux linkage between the flux generated by the permanent magnets and the stator windings, which is a relatively high number of inactive linkages. In general, as shown in fig. 1, for a fractional slot concentrated winding permanent magnet synchronous motor with a stator winding 1 'being a near-pole slot, four coils 10' forming one phase are divided into two groups, and two coils 10 'of each group are respectively wound on stator slots 20' formed by two adjacent stator teeth. In the related art, the method of optimizing harmonic radial electromagnetic force is adopted to improve the noise of the motor, but once the pole slot matching of the motor is determined, the lowest order radial electromagnetic force always exists, the effect brought by optimization is not obvious, and in addition, the harmonic radial electromagnetic force is generated by the interaction of harmonic flux densities, and the harmonic flux densities also influence the efficiency of the motor.
Disclosure of Invention
The present invention is directed to solving at least one of the problems of the prior art or the related art.
To this end, a first aspect of the invention proposes a synchronous machine.
A second aspect of the present invention proposes a compressor.
In view of this, a first aspect of the present invention proposes a synchronous machine comprising: a rotor core; the stator core is arranged around the outer side of the rotor core and provided with an annular magnetic yoke and a plurality of convex teeth which are distributed at intervals along the circumferential direction of the central line of the annular magnetic yoke, the plurality of convex teeth comprise a plurality of tooth groups, each tooth group comprises a first tooth and a second tooth which are sequentially arranged along the rotating direction of the rotor core, and coils with the same phase are wound on the first tooth and the second tooth; the stator winding comprises a plurality of coils which are connected, the coils are arranged in stator slots of the stator core and wound on the convex teeth, the coils comprise a first type of coil and a second type of coil, the stator winding is a three-phase stator winding, each phase of stator winding is provided with at least three joints, the three joints comprise a first joint, a second joint and a third joint, the first joint and the second joint in each phase of stator winding are arranged on the first type of coil, and the third joint in each phase of stator winding is arranged on the second type of coil; the first joint in each phase of stator winding is connected with the second joint in the adjacent phase of stator winding; the second type coil in each phase of stator winding is connected with the first type coil, and the third joint in each phase of stator winding is connected with the corresponding three-phase power supply lead wire or the third joint in the other phase of stator winding; the number of the stator slots A1 and the number of the magnetic poles A2 of the rotor core meet the following conditions: a2-a1 ═ 2.
The present invention provides a synchronous motor comprising: rotor core, stator core and stator winding. The relation between the number A1 of stator slots and the number A2 of magnetic poles of a rotor core is reasonably set, so that A2-A1 is 2, the stator core of the synchronous motor comprises a plurality of convex teeth which are circumferentially distributed at intervals on the inner side of an annular magnetic yoke, the convex teeth can be divided into a plurality of tooth groups, coils with the same phase are wound on each tooth group, any two adjacent tooth groups are wound with coils with different phases, the first convex tooth which is sequentially arranged in the rotation direction of the rotor core in each tooth group is taken as a first tooth, the second convex tooth which is sequentially arranged in the rotation direction of the rotor core in each tooth group is taken as a second tooth, a magnetic flux path is optimized, the back electromotive force can be effectively improved, the copper consumption of windings is reduced, and the high-output synchronous motor is realized; further, the coils of the stator winding include a first type coil and a second type coil, wherein, from the perspective of the non-in-phase stator winding, a first joint on the first type coil is connected with a second joint on the first type coil of the adjacent phase, that is, the first type coil is connected in an end-to-end manner between the adjacent phases, that is, an angular connection is adopted, the second type coil is connected with the first type coil of the same phase, when the second type coil is connected with the first type coil through the first joint or the second joint, the second type coil of the same phase, the first type coil and the first type coil of the adjacent phase which are simultaneously connected with each other form a star connection, when the second type coil is connected in the first type coil, the first type coil of the same phase and the second type coil form a star connection, specifically, a third joint on the second type coil also has two connection methods, one is connected with the corresponding three-phase power supply lead wire, and as the terminal of the power supply, the second terminal is connected with the third connectors of other phases, namely tail-to-tail star connection is adopted among the three phases, the connection mode of the stator winding adopts a combination of angle connection and star connection, compared with the conventional single-layer cross type and concentric type windings, the low-order magnetic potential harmonic of the near-pole slot built-in permanent magnet motor can be reduced, the motor efficiency is improved, and the beneficial effect of reducing the vibration noise of the motor can be obtained.
Specifically, the combination of the synchronous motor matched with the special-grade slots, the winding mode of the convex teeth and the coils and the connection mode of the stator winding effectively improves the counter electromotive force and inhibits low-order magnetic potential harmonics, so that a high-output motor is provided, and the vibration noise of the motor can be improved.
According to the synchronous machine of the invention, the following additional technical features can be provided:
in the above technical solution, preferably, a1 is 12 and a2 is 14.
In this embodiment, the numbers of a1 and a2 include, but are not limited to, a 1-12 and a 2-14. It is also possible that a 1-14 and a 2-16, a 1-16 and a 2-18, a 1-18 and a 2-20, etc. The winding mode of the motor matched with the specific grade slot, the convex teeth and the coil and the connection mode of the stator winding are combined, so that the vibration noise of the motor can be greatly reduced, and the use performance and the market competitiveness of the product are improved.
In any of the above technical solutions, preferably, a value range of a ratio N2/N1 of the number of turns N2 of the second type coil to the number of turns N1 of the first type coil is 0.49 or more and N2/N1 or less and 0.6 or less; the value range of the ratio d2/d1 of the bare wire diameter d2 of the second type coil to the bare wire diameter d1 of the first type coil is that d2/d1 is more than or equal to 1.1 and less than or equal to 1.6.
In the technical scheme, the relationship between the number of turns of the two types of coils and the diameter of the bare wire is respectively and specifically defined. When the turns of the coils are the same, the potential and the magnetic potential generated by the angle-shaped connected coil are 1.732 times lower than those generated by the star-shaped connected coil, so that the difference between the induced potential and the magnetic potential is caused, and the difference between the potential and the magnetic potential of the first type coil is compensated by increasing the turns of the angle-shaped connected coil (namely the first type coil), so that the potential and the magnetic potential of the first type coil and the second type coil are more balanced. Since the sizes of the stator slots are equal, by limiting the value of d2/d1 to be greater than 1, the bare wire diameter d1 of the first type coil can be reduced to correspondingly increase the number of turns N1 of the first type coil arranged in the stator slot to satisfy the aforementioned turn ratio.
In any of the above technical solutions, preferably, a value range of a ratio T2/T1 of the number T2 of the second type of coils to the number T1 of the first type of coils is 0.4 ≤ T2/T1 ≤ 1.
In the technical scheme, the number ratio of the second type of coil to the first type of coil is specifically limited, and when T2/T1 is 1, the two types of coils are equal in number, so that the balance of the whole structure and the working reliability of the motor are ensured; the lower limit value of T2/T1 is limited to 0.4, so that the integral structure unbalance caused by the overlarge difference of the two types of coils is avoided, and the flexibility of the arrangement of the number of the coils can be improved.
In any of the above-described aspects, preferably, a winding direction of the coil on the first tooth is opposite to a winding direction of the coil on the second tooth.
In this technical scheme, the winding direction through setting for the coil on the first tooth is opposite with the winding direction of the coil on the second tooth, makes things convenient for the coiling on the one hand, and on the other hand can reduce the length of coil, practices thrift the cost, and is favorable to rotor core to rotate steadily.
In any one of the above technical solutions, preferably, the rotor core includes: the rotor punching sheet comprises a rotor punching sheet and a slot, wherein a magnet is arranged in the slot; the permanent magnets are arranged in a straight line or V shape on any horizontal section of the rotor core, or the permanent magnets are tangentially magnetized magnets.
In the technical scheme, the rotor core is provided with slots for inserting the magnets, the magnets are permanent magnets, the permanent magnets can be distributed in a straight line shape or a V-shaped shape relative to any horizontal section of the rotor core, or are tangential magnetizing magnets, when the permanent magnets are distributed in a V-shaped shape or the tangential magnetizing magnets, the magnetism gathering effect is good, the main flux is higher, the back electromotive force is high, and therefore the running efficiency of the synchronous motor is high. Of course, the permanent magnets may also be magnets of other shapes, such as a hybrid of radial and tangential configurations. Preferably, the permanent magnet is a rare earth magnet, a ferrite magnet, or a rare earth and ferrite mixed magnet.
In any of the above technical solutions, preferably, on any horizontal cross section of the rotor core, the sum of the lengths of the magnets under each pole is bm, the inner diameter of the stator core is Di, and the number of pole pairs on the rotor core is P, wherein bm × 2P/(pi × Di) is not less than 0.75 and not more than 0.9.
In the technical scheme, the sum of the lengths of the magnets under each pole on any horizontal section of the rotor core is set to be bm, for example, when each pole comprises two magnets, the sum of the lengths of the two magnets is bm, the inner diameter of the stator core is Di, the number of pole pairs on the rotor core is P, and the sum of the lengths of the two magnets is 0.75-bm multiplied by 2P/(pi multiplied by Di) and 0.9, so that the highest utilization rate and the optimal cost performance of the permanent magnet can be realized, and the operating efficiency of the synchronous motor is improved.
In any of the above technical solutions, preferably, when the permanent magnets are distributed in a V shape, an included angle of the V shape ranges from 90 ° to 130 °.
In the embodiment, the included angle of the permanent magnets distributed in a V shape is set to be 90-130 degrees, so that the maximization of the back electromotive force fundamental wave can be realized, the copper loss of the winding is reduced, and the operation efficiency of the synchronous motor is improved. The permanent magnets are distributed in a V shape, and can be one V-shaped permanent magnet or two permanent magnets forming a V shape.
In any of the above technical solutions, preferably, the central angle corresponding to the pole crown of the rotor core of the synchronous motor is
In the technical scheme, the central angle corresponding to each pole crown of the rotor core of the synchronous motor is
In any of the above technical solutions, preferably, a ratio of the inner diameter Di of the stator core to the outer diameter Do thereof satisfies: Di/Do is more than or equal to 0.52 and less than or equal to 0.57.
In the technical scheme, the ratio of the inner diameter Di of the stator core to the outer diameter Do thereof is set to satisfy the following conditions: Di/Do is more than or equal to 0.52 and less than or equal to 0.57, so that the optimal cost performance can be obtained while the rotational inertia is met, and the production cost of the synchronous motor is reduced.
In any of the above technical solutions, preferably, the rated torque of the synchronous machine is T, the inner diameter of the stator core is Di, and the unit volume torque of the rotor of the synchronous machine is TPV, which satisfy: 5.18
In the technical scheme, the rated torque of the synchronous motor is T, the inner diameter of a stator core is Di, the unit volume torque of a rotor is TPV, and the requirements of 5.18 multiplied by 10 are met-7≤T×Di-3×TPV-1≤1.17×10-6Wherein the value range of the unit volume torque TPV is 5 kN.m.m-3≤TPV≤45kN·m·m-3The power requirement of the compressor can be met by the synchronous motor through limiting the value range of the combined variable of the rated torque T of the synchronous motor, the inner diameter Di of the stator core and the unit volume torque TPV of the rotor, and in addition, the synchronous motor adopting the rotor and the synchronous motor adopting the rotorThe compressor can effectively reduce the magnetic leakage of the rotor, increase the utilization rate of the permanent magnet and improve the efficiency of the synchronous motor.
A second aspect of the present invention provides a compressor comprising: a synchronous machine as claimed in any one of the preceding claims.
The compressor provided by the invention comprises the synchronous motor according to any one of the technical schemes in the first aspect, so that the compressor has all the beneficial effects of the synchronous motor, and the description is omitted.
Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
fig. 1 is a schematic wiring diagram of a stator winding in the related art;
FIG. 2 is a schematic wiring diagram of the stator windings of one embodiment of the present invention;
fig. 3 is a schematic structural view of a compressor according to an embodiment of the present invention.
Wherein, the corresponding relation between the reference numbers and the part names in fig. 1 is:
1 ' stator winding, 10 ' coil, 20 ' stator slot;
the correspondence between reference numerals and part names in fig. 2 and 3 is:
20 compressor, 22 synchronous motor, 222 rotor core, 224 stator core, 226 stator winding, 228 coil, 230 stator slot, a1-1 first phase first group first connector, a1-2 first phase second group first connector, a2-1 first phase first group second connector, a2-2 first phase second group second connector, A3-1 first phase first group third connector, A3-2 first phase second group third connector, B1-1 second phase first group first connector, B1-2 second phase second group first connector, B2-1 second phase first group second connector, B2-2 second phase second group second connector, B3-1 second phase first group third connector, B3-2 second group third connector, C1-1 third phase first group first connector, C1-2 third group first connector, c2-1 third phase first group second connector, C2-2 third phase second group second connector, C3-1 third phase first group third connector, C3-2 third phase second group third connector.
Detailed Description
In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.
The
As shown in fig. 2 and 3, an embodiment of the first aspect of the present invention proposes a synchronous machine 22 including: a rotor core 222; a stator core 224 surrounding the rotor core 222, wherein the stator core 224 is provided with an annular yoke and a plurality of teeth circumferentially distributed at intervals along a center line of the annular yoke, the plurality of teeth includes a plurality of tooth groups, each tooth group includes a first tooth and a second tooth sequentially arranged along a rotation direction of the rotor core 222, and coils 228 having the same phase are wound on the first tooth and the second tooth; a stator winding 226, the stator winding 226 including a plurality of coils 228 connected to each other, the plurality of coils 228 disposed in stator slots 230 of the stator core 224 and wound on the plurality of teeth, the plurality of coils 228 including a first type of coil and a second type of coil, the stator winding 226 being a three-phase stator winding, at least three terminals including a first terminal, a second terminal and a third terminal being provided for each phase of the stator winding 226, the first terminal and the second terminal being provided for each phase of the stator winding 226, and the third terminal being provided for each phase of the stator winding 226 on the second type of coil; a first terminal in the stator winding 226 of each phase is connected to a second terminal in the stator winding 226 of an adjacent phase; the second type coil in each phase of stator winding 226 is connected with the first type coil, and the third joint in each phase of stator winding 226 is connected with the corresponding three-phase power supply lead wire or the third joint in the stator winding 226 of other phases; the number A1 of the stator slots 230 and the number A2 of the magnetic poles of the rotor core meet the following conditions: a2-a1 ═ 2.
The present invention provides a
Specifically, the combination of the
The derivation process of the magnetic potential of the stator winding 226 is:
it can be seen from the formula derivation that, by adopting the connection mode of the stator winding 226 of the present invention, the electromagnetic field side does not have low-order harmonic rotation magnetic potential, so that the performance of the