WO1999035731A1

WO1999035731A1 - Slotless synchronous generator

Info

Publication number: WO1999035731A1
Application number: PCT/CN1998/000321
Authority: WO
Inventors: Zhenxia Xiao
Original assignee: Zhenxia Xiao
Priority date: 1997-12-31
Filing date: 1998-12-30
Publication date: 1999-07-15
Also published as: AU1747599A

Abstract

A static or dynamic exciter slotless synchronous generator characterized in that a stator comprises a hollow cylinder and two discs connecting with the two ends of the hollow cylinder, a stator support is made of non-magnetic material, each of the two discs provides radiant uniform notches. Each of the stator core is provided in each pair of the corresponding notches of the two discs and is wound with a stator coil, stator coils provide Y-connection or DELTA -connection. A rotor includes a shaft, around which a rotor core and two pole discs at its two outer ends are fixed. The rotor core positions within bore of the hollow cylinder, and the two pole discs position at outer side of the two discs, respectively, and uniform salient poles position on the outer surface of the each pole disc; gaps are provided between the salient poles and coupling surface of the stator, the pole discs and the discs, the rotor core and the hollow cylinder. The electric machine in accordance with this invention provides the advantages of small volume, low loss, high efficiency, cheap cost and easy maintenance.

Description

Slotless Synchronous Generator Technical Field

The invention relates to a slotless motor, in particular to a static-field type or moving-field type synchronous generator which does not require slotting of the stator and rotor iron cores.

Background technique

A general-purpose generator mainly includes two parts, the stator and the rotor. The stator core is made of laminated circular silicon steel sheets insulated from each other. Several grooves need to be punched on each lamination, and the grooves are embedded with There are stator coils, and the rotor includes a rotating shaft. The rotating shaft is covered with rotor poles punched and laminated from silicon steel sheets, and excitation coils are wound around the rotor poles. This traditional generator has the following deficiencies:

1. Large volume, high iron loss, and low power generation efficiency. Since both the stator core and the magnetic pole need to be grooved, the silicon steel sheet used cannot use high-silicon silicon steel sheets, but only low-silicon silicon steel sheets. The silicon steel sheet has low magnetic permeability and low magnetic flux density. Under the condition of the same generator power, the amount of silicon steel sheet is large, resulting in a large, heavy generator, high iron loss, and low power generation efficiency;

2. The material utilization rate is low and the cost is high. When making the stator core, circular chips are punched out from the rectangular silicon steel sheet. The utilization rate of the silicon steel sheet is only 60%, which is a factor of high cost. One, the second factor of high cost is that the stator coils are respectively embedded in two grooves with a pitch interval, the span of the coil is large, and the part of the coil protruding out of the slot cannot cut the magnetic force line, and the part that does not cut the magnetic force line occupies the entire 20-40% of the stator coil, that is, the effective utilization rate of the enameled wire is low, and the third factor of the high cost is the need for a high-precision, expensive composite punching die. The composite punching film is easily damaged in frequent use and has a low service life;

3. Maintenance is difficult. In three-phase generators, one-phase stator coils often burn out. During maintenance, most of the other intact two-phase stator coils are removed together with the burnt-out phase and rewound. system, both labor-intensive and wasteful;

4. Carbon brushes are easy to wear. Carbon brushes are essential parts of generators. During use, carbon brushes are easily worn out. If they are worn out, they must be stopped for replacement, which will affect the use.

Application No. 95105914.9 discloses an ironless excitation generator. The rotor iron core of this generator is essentially a pair of magnetic poles, and an excitation coil is wound on it. There is no novelty. Since the rotor part has no iron core, the magnetic The flux density is tens to hundreds of times smaller, the practical value is small, and it is difficult to popularize.

disclosure of invention

The purpose of the present invention is to provide a slotless synchronous generator with low cost and high power generation efficiency, including static excitation Or dynamic excitation type synchronous generator.

This slotless synchronous generator includes a stator and a rotor. It is characterized in that the stator consists of a hollow cylinder and two discs connected together at both ends of the hollow cylinder, and a stator bracket made of non-magnetic material. Each Notches are evenly distributed on the disc. A stator core is installed in each pair of gaps corresponding to the two disks, and a stator coil is wound on each stator core, and each stator coil is connected in a star or triangle; the rotor includes a rotating shaft, and the inherent rotor is sleeved on the rotating shaft The iron core and the two pole disks fixed at the two outer ends of the rotor iron core. The rotor core is located in the inner cavity of the hollow cylinder, and the two pole plates are respectively located on the outer sides of the two discs. Salient poles are evenly distributed on the outer ring surface of each pole plate. Between the salient poles and the coupling surface of the stator core, There are gaps between the pole disc and the disc and between the rotor core and the hollow cylinder.

The slotless synchronous generator of the present invention can have two excitation modes, that is, static excitation mode or dynamic magnetic field mode. The feature of the slotless static excitation synchronous generator of the present invention is that the excitation coil is wound on the hollow cylinder forming the stator support.

The feature of the slotless dynamic field synchronous motor of the present invention is that the rotor shaft is equipped with a slip ring in contact with the carbon brush; the excitation coil introduced by the slip ring is mounted on the rotor core on the rotor shaft. Both the rotor core and the field coil are located in the inner cavity of the hollow cylinder. The number of salient poles is an integer of 2, the number of stator cores is an integer multiple of 3 of the number of salient poles, and the central angle of the arc length of each salient pole is the central angle of the arc length occupied by the distance between two adjacent salient poles The coupling surface between the salient pole and the stator core is an arc surface or a plane. The arc surface includes a cylindrical arc surface and a conical arc surface. The contact surface between the two pole plates and the rotor core is preferably a conical surface. The angle between the conical surface and the rotating shaft is 40 ° - 50 °. The stator core and the pole plate are made of laminated high-silicon silicon steel sheets. The rotor core is rolled with high-silicon silicon steel strips. The cross-sectional shape of the stator core is Corresponds to the shape of the notch on the disc. For the convenience of use, the slotless static excitation synchronous generator also includes a left end cover and a right end cover which are sleeved on the rotating shaft through bearings, and a fixing bolt is connected between the left end cover and the right end cover, and the two discs are respectively fixed on the left end cover and the right end cover .

In the generator of the present invention, for example, in a static excitation synchronous generator, a DC current is directly passed through the excitation coil, or, for example, in a moving field synchronous generator, a carbon brush or slip ring is used to A direct current is passed through the excitation coil. The direct current generates a magnetic field, and the direction of the magnetic force lines of the magnetic field is s-pole pole disk salient pole → S pole pole disk-rotor core-N-pole pole disk-N-pole pole disk salient pole-N-pole pole disk salient pole and stator core Coupling surface gap—stator core + stator coil → stator core and S pole disk salient pole coupling surface gap—S pole pole disk salient pole, when the prime mover drives the rotating shaft to rotate at high speed, the rotor core and the two pole disks also With the high-speed rotation, the number of magnetic force lines passing through the stator coil on each stator core changes periodically every time the pole disc rotates once, that is, when the stator core corresponds to the center of each salient pole, The magnetic force lines passing through are the most, and the left and right deviate from the center of the salient pole, the magnetic force lines passing through the stator coil will decrease, the longer the deviation, the more the magnetic force lines will be reduced, when the stator core corresponds to the salient pole When there is a gap between the stator coils, no magnetic force lines pass through the stator coils. Since the magnetic force lines passing through each stator coil are dense, sparse, non-existent, sparse, and dense, it is equivalent to the stator coils periodically cutting the magnetic force lines. The induced electromotive force is generated on each stator coil, and the stator wires are connected in star or delta to supply power to the load.

Therefore, the slotless synchronous generator of the present invention has the following advantages:

1. Small size, low iron loss, high power generation efficiency, because the stator core and rotor core do not need punching slots. Therefore, it can be made of high-silicon silicon steel sheet. The magnetic permeability of high-silicon silicon steel sheet is 2.5 times that of low-silicon silicon steel sheet. Under the same magnetic flux density, the stator core made of high-silicon silicon steel sheet And the volume of the rotor core is 2.5 times smaller than that made of low silicon, and the weight is reduced accordingly. The iron loss can be reduced by 70-80%, and the efficiency of the generator is increased from 80-85% of the traditional structure to 90- 95%;

2. The utilization rate of materials is high, the manufacturing process is simple, and the cost is low. Since the stator core is a long lamination, there is almost no corner waste during production, and the utilization rate of materials can reach 99%. Since the stator coil is directly wound on a small There is no span on the stator core, and all the magnetic field lines are cut, so the enameled wire used in the stator coil is less. Compared with the traditional structure of the generator, the copper can be saved by 40-60%, and the copper loss is also reduced accordingly. Because the stator iron Both the core and the rotor core do not need punching slots, thus eliminating the need for expensive composite dies and the stamping process in manufacturing, which simplifies the machining methods. From the above, the cost of the generator can be greatly reduced;

3. Easy maintenance. Since the stator coils are on their own stator cores and do not cross and overlap each other, this greatly facilitates maintenance. During maintenance, only the damaged stator coils need to be replaced, and the rest of the intact stator coils can be replaced as usual. , saving maintenance costs.

4. The cooling device is simplified. Due to the use of high-silicon silicon steel sheet and static excitation structure, the cooling device can be omitted for small generators, and the cooling device is simplified for large generators, ensuring the reliability of motor operation.

In addition, the slotless static excitation synchronous generator of the present invention also has the following advantages: strong and durable, long life, zero electrical failure rate of the rotor, carbon brushes are omitted, and due to the static excitation structure, the The carbon brushes are extremely easy to wear, which prevents the phenomenon of stopping the machine to replace the carbon brushes and affecting the use.

Description of drawings

Now the present invention is described in detail in conjunction with following accompanying drawings:

Fig. 1 is a front view of an embodiment of a slotless static excitation synchronous generator;

Fig. 2 is a front view of an embodiment of a slotless static excitation synchronous generator with left and right end covers;

Fig. 3 is a front view of an embodiment of a slotless moving field synchronous generator;

Fig. 4 is a front view of an embodiment of a slotless dynamic field synchronous generator that often has left and right end covers;

Fig. 5 is the left side view among Fig. 1 or Fig. 3 embodiment; Fig. 6 is the schematic diagram that the coupling surface of the salient pole and the stator iron core is a truncated conical arc surface in each embodiment of the present invention; Fig. 7 is the schematic diagram that the coupling surface of the convex plate and the stator iron core is a truncated conical arc surface

Fig. 8 is a schematic diagram that the coupling surface of the convex plate and the stator core is a plane.

Fig. 9 shows a front view of another embodiment of the stator structure of the present invention;

Fig. 10 is a left side view of the embodiment in Fig. 9.

Best Mode for Carrying Out the Invention

1, 2 and 5 to 9, in an embodiment of the slotless static excitation synchronous generator of the present invention, the slotless synchronous generator includes a stator and a rotor, and the stator includes a hollow cylinder 1 and the hollow cylinder 1 The stator support is composed of two disks 2 connected at both ends of the body, the stator support is made of non-magnetic material aluminum, plastic or bakelite, and each disk 2 is provided with 9 square gaps that are evenly distributed in a radial shape A stator core 3 is installed in each pair of square gaps corresponding to the two disks 2. The stator core 3 is made of laminated high-silicon steel sheets, and its cross-sectional shape corresponds to the square gap of the disk 2. Each certain Stator coils 4 are wound on the sub-core 3, and the stator coils 4 are connected in a star or triangle shape. The excitation coil 5 is wound on the hollow cylinder 1. The rotor includes a rotating shaft 6, and the rotating shaft 6 is covered with high-silicon silicon steel. Rolled rotor core 7 and two pole plates 8 fixed to the two outer ends of the rotor core 7 and laminated with high-silicon silicon steel sheets. The contact surfaces of the two pole plates 8 and the rotor core 7 are the closest Preferably it is a conical surface. The angle between the conical surface and the rotating shaft 6 is 40°-50°. The fixing method between the pole plate 8 and the rotor core 7 can be fixed screws. The rotor core 7 is located in the inner cavity of the hollow cylinder 1 Among them, the two pole disks 8 are respectively located on the outer sides of the two disks 2, and three salient poles 9 are evenly distributed on the outer ring surface of each pole disk 8, and the arc lengths of each salient pole 9 have central angles adjacent to each other. The distance between the two salient poles 9 is twice the central angle of the arc length. The coupling surface between the salient poles 9 and the stator core 3 can be an arc surface or a plane. The arc surface includes a cylindrical arc surface and a frustoconical arc surface, the gap between the salient pole 9 and the coupling surface of the stator core 3 is 0. 15-0. 30 mm, the gap between the pole disc 8 and the disc 2 is 0. 30-0. 50 leg, the rotor iron The gap between the core 7 and the hollow cylinder 1 is 0.25-1.20mm. For the convenience of use, the generator also includes a left end cover 11 and a right end cover 12 which are sleeved on the rotating shaft 6 through a bearing 10. On the left end cover 11 A fixing bolt 13 is connected between the right end cover and the right end cover 12, and the two discs 2 are respectively fixed on the left end cover 11 and the right end cover 12.

3 to 9, in the embodiment of the slotless dynamic field synchronous generator of the present invention, the slotless synchronous motor includes a stator and a rotor, and the stator includes a hollow cylinder 1 connected to both ends of the hollow cylinder 1. The stator bracket composed of two integrated discs 2, the stator bracket is made of non-magnetic material aluminum, plastic or bakelite, each disc 2 is provided with 9 square notches that are evenly distributed in a radial shape, Each pair of square gaps corresponding to the disk 2 is equipped with a stator core 3. The stator core 3 is made of laminated high-silicon silicon steel sheets. Its cross-sectional shape corresponds to the square gap of the disk 2. Each stator core 3 Stator coils 4 are wound on it, and each stator coil 4 is connected in star or delta, and the rotor Including the rotating shaft 6, the right rotating shaft 6 is equipped with a slip ring 14 in contact with the carbon brush 15, and is also covered with a rotor core 7 rolled with a high-silicon silicon steel strip and fixed to the two outer ends of the rotor iron core 7 and fixed with a high-silicon steel strip. Two pole disks 8 made of laminated silicon steel sheets. The contact surface between the two pole disks and the rotor core 7 is preferably a conical surface. The angle between the cone surface and the rotating shaft 6 is 40°-50°. The pole disk 8 The fixing method with the rotor core 7 can be fixed screws, the rotor core 7 is wound with an excitation coil 5, the rotor core 7 and the excitation coil 5 are located in the inner cavity of the hollow cylinder 1, and the two pole plates 8 are respectively located in On the outside of the two discs 2, three salient poles 9 are evenly distributed on the outer ring surface of each pole disc 8, and the central angle of the arc length of each salient pole 9 is occupied by the distance between two adjacent salient poles 9 Twice the central angle of the arc length, the coupling surface between the salient pole 9 and the stator core 3 can be an arc surface, or it can be a plane, and the arc surface includes a cylindrical arc surface and a frustum-shaped arc surface, and the salient pole 9 and the stator iron core The gap between the coupling surfaces of the core 3 is 0. 15-0. 30mm, the gap between the pole plate 8 and the disc 2 is 0. 30-0. 50mm, and the gap between the rotor core 7 and the hollow cylinder 1 The gap is 0.25-1.20mm. For the convenience of use, the generator also includes a left end cover 11 and a right end cover 12 which are set on the rotating shaft 6 through a bearing 10, and a fixing bolt 13 is connected between the left end cover 11 and the right end cover 12 , Two discs 2 are fixed on the left end cover 11 and the right end cover 12 respectively.

In each embodiment of the present invention, the specific number of salient poles 9 on the pole plate 8 in industrial production, under the condition of satisfying 2, the principle of determination is: the speed of the generator is determined by the speed of the prime mover, and the speed of the generator is determined by the speed of the generator The number of stator cores, the number of stator cores, the quotient of the number of stator cores ÷ 3 is the number of salient poles.

The structure of the stator core of the present invention can also be further improved, that is, the stator core is made of cold-rolled oriented silicon steel sheets and at the same time (C 1 1 ) the arrangement of the silicon steel sheets is changed from vertical to horizontal, which is more conducive to the magnetic circuit. The reduction of reluctance increases the intensity of magnetic flux.

Because it is an oriented silicon steel sheet, its magnetic force lines can only be transmitted along the direction of the iron core. In order to facilitate the concentrated conduction of the magnetic force lines, at the same time, the iron core is changed from vertical to horizontal, and then bent. This form is more conducive to the stator. The connection between the magnetic circuit of the iron core and the magnetic circuit of the iron core of the pole plate in order to reduce the reluctance is shown in Figure 9 and Figure 10 .

From the comparison of Fig. 10 and Fig. 5, such improvement is more conducive to the smooth flow of the (C 1 2 ) magnetic circuit, the reduction of magnetic flux leakage, the enhancement of the air gap magnetic field, and the corresponding improvement of generator efficiency. The silicon steel sheet used in the pole plate is still generally non-oriented cold-rolled high-silicon silicon steel sheet stacked, and its magnetic force lines can be transmitted along a magnetic pole direction arbitrarily.

Claims

Quan HeiJ Requirements

1. A slotless synchronous generator, comprising a stator and a rotor, characterized in that the stator and the rotor are characterized in that the stator consists of a hollow cylinder and two discs connected to the two ends of the hollow cylinder, and is used The stator bracket made of non-magnetic material has gaps evenly distributed on each disk; a stator core is installed in each pair of gaps corresponding to the two disks, and a stator coil is wound on each stator core. The stator coils are connected in star or delta; the rotor includes a rotating shaft, on which there is a fixed rotor core and two pole plates fixed at the two outer ends of the rotor core; the rotor core is located in the inner cavity of a hollow cylinder, and the two poles The pole disks are respectively located on the outer sides of the two disks, and salient poles are evenly distributed on the outer ring surface of each pole disk, between the salient poles and the coupling surface of the stator core, between the pole disk and the disk, and between the rotor core and the There are gaps between the hollow cylinders.

2. A synchronous generator as claimed in claim 1, characterized in that: in the slotless static excitation synchronous generator, the excitation coil is wound on the hollow cylinder forming the stator support.

3. A synchronous generator as claimed in claim 1, characterized in that: a slip ring in contact with the carbon brush is installed on the rotating shaft, and the excitation coil introduced by the slip ring is installed on the rotor core at the upper opening of the rotor shaft, and the rotor iron Both the core and the field coil are located in the inner cavity of the hollow cylinder.

4. A synchronous generator as claimed in claim 1, further comprising: a left end cover and a right end cover which are sleeved on the rotating shaft through a bearing, a fixing bolt is connected between the left end cover and the right end cover, and the two disks are respectively Fastened to the right end cap and the right end cap.

5. The slotless static excitation synchronous generator according to claim 1, characterized in that the number of salient poles is an integer of 2, the number of stator cores is an integer multiple of 3 of the number of salient poles, and the arc length of each salient pole is The central angle of is twice the central angle of the arc length occupied by the distance between two adjacent salient poles.

6. The synchronous generator according to claim 1, characterized in that the cross-sectional shape of the stator core corresponds to the shape of the notch on the disc.

7. The synchronous generator according to claim 1, characterized in that the coupling surface between the salient pole and the stator core is an arc surface or a plane.

8. The synchronous generator according to claim 7, wherein the arc surface includes a cylindrical arc surface and a frustoconical arc surface.

9. The synchronous generator according to claim 1, characterized in that the contact surfaces between the two pole plates and the rotor core are conical surfaces, and the angle between the conical surfaces and the rotating shaft is 40°-50°.

10. The synchronous generator according to claim 1, characterized in that the coupling surface between the salient pole and the stator core The gap between them is 0. 15-0. 30mm, the gap between the pole plate and the disc is 0. 30-0. 50mm, the gap between the rotor core and the hollow cylinder is 0. 25-1. 20mm .

11. The synchronous generator according to claim 1, characterized in that the stator core and the pole plate are made of laminated high-silicon steel sheets, and the rotor core is rolled with high-silicon steel strips.

12. The synchronous generator according to claim 1, characterized in that: the stator core is made of cold-rolled oriented high-silicon silicon steel sheet.

13. The synchronous generator according to claim 12, characterized in that: wherein said oriented high-silicon silicon steel sheets are arranged flat and then bent.