Double-disc rotor bracket of large-scale through-flow unit

Abstract

The invention belongs to the field of tubular hydraulic generators, and particularly relates to a double-disc rotor support structure of a large tubular unit. Comprising a center body, an upper disc, a lower disc, an upper annular plate, a lower annular plate and a magnet yoke ring. The center body, the upper disc, the lower disc, the upper annular plate 4 and the lower annular plate are arranged on the inner side of the magnet yoke ring, and the center body and the magnet yoke ring are fixedly connected through the upper disc and the lower disc. A plurality of vertical ribs are arranged between the upper disc and the lower disc; a plurality of upper ring supporting plates are arranged between the upper ring plate and the upper disc. The rotor is provided with the upper disc and the lower disc, large rotor weight and centrifugal force can be borne, stress is more uniform, internal stress and stress concentration between the center body and the discs are avoided, and the problem of fatigue fracture under alternating stress is solved.

Description

Technical Field

[0001] The present invention belongs to the field of tubular hydro-generators, and particularly relates to a double-disc rotor bracket structure for large tubular units. Background Art

[0002] Bulb tubular units are commonly used models for hydropower generation in river basins. Currently, they are developing towards large capacity and multiple operating conditions. Among them, some power stations have a demand for ultra-low head power generation, resulting in an increase in the runaway speed of the units, and the design difficulty of the rotating parts of the generator, especially the rotor bracket, has increased significantly.

[0003] The rotor bracket is an intermediate component that connects the magnetic yoke and the rotating shaft into one body. At the same time, it is also a blower element of the ventilation system. It is subjected to complex forces and is one of the most critical components of the entire unit. If the structural stiffness of the rotor bracket is small and the stress amplitude changes greatly, fatigue failure is likely to occur; when the structural stiffness of the rotor bracket is large, it often has the characteristic of high stress level and is prone to static failure. This phenomenon becomes obvious as the unit capacity increases. Therefore, in the design of large bulb tubular units, the structure of the rotor bracket is crucial for ensuring the safe operation of the unit.

[0004] At present, the rotor bracket and the magnetic yoke of large bulb tubular units are often made into one body. The commonly used rotor bracket structures are single-disc rotor brackets and inclined vertical rib rotor brackets. In recent years, cracks and even fractures have occurred in the rotor brackets of some large-capacity tubular units with single-disc rotor bracket and inclined vertical rib rotor bracket structures. The main reason is that since the bulb unit is a horizontal unit, when the unit is operating normally, the rotor bracket has to bear, in addition to the rated torque, the gravitational moments of the poles and the magnetic yoke, its own centrifugal force and unbalanced magnetic pull, but also the action of comprehensive forces such as its own gravity and axial alternating force. As the capacity increases, the size and weight of the unit also become larger and larger. At this time, the traditional single-disc and inclined vertical rib structures of the rotor brackets of large-capacity tubular units are relatively weak and the rib plates are prone to deformation. Cracks in the rotor bracket will greatly affect the safe and stable operation of the power station, and even if processed on site, the occurrence of fractures cannot be eliminated. After some rotor brackets are repaired, new crack areas even appear, greatly affecting the safe and stable operation of the power station.

[0005] Therefore, there is an urgent need for a rotor bracket of a large tubular hydro-generator with high stiffness and the ability to withstand alternating loads to solve these problems. Summary of the Invention

[0006] This application has upper and lower discs, which can bear a large rotor weight and centrifugal force, the stress is more uniform, avoiding the internal stress and stress concentration between the central body and the disc, and solving the fatigue fracture problem under alternating stress.

[0007] The present application adopts the following technical solutions: A double-disc rotor bracket structure for a large tubular turbine unit, comprising: a central body, an upper disc, a lower disc, an upper ring plate, a lower ring plate, and a yoke ring; the central body, the upper disc, the lower disc, the upper ring plate, and the lower ring plate are arranged inside the yoke ring, and the central body is fixedly connected to the yoke ring through the upper disc and the lower disc; a plurality of upper disc ventilation holes are evenly arranged on the circumference of the upper disc, and a plurality of lower disc ventilation holes are evenly arranged on the circumference of the lower disc, and the circumferential arrangement directions of the upper disc ventilation holes and the lower disc ventilation holes correspond one by one to increase the air flow rate of the ventilation holes; a plurality of vertical ribs are arranged between the upper disc and the lower disc; a plurality of upper ring support plates are arranged between the upper ring plate and the upper disc.

[0008] Further, a plurality of upper ring reinforcing ribs are arranged below the upper ring plate, and a plurality of lower ring reinforcing ribs are arranged below the lower ring plate to increase the overall stiffness of the rotor bracket.

[0009] Further, a brake ring is fixedly arranged on the yoke ring, and the brake ring is tightly connected to the upper ring plate.

[0010] Further, yoke ventilation holes and pole fixing holes are evenly arranged on the circumference of the yoke ring. The yoke ventilation holes are located between the poles, and the pole fixing holes are located at the center line of each pole. The circumferential number of the yoke ventilation holes and the pole fixing holes is the same as the number of poles, and the number in the axial direction is set according to the length of the yoke ring.

[0011] Further, arc-shaped notches are formed at the positions corresponding to the yoke ventilation holes at the joints of the vertical ribs, the upper ring support plates, and the lower ring reinforcing ribs and the yoke ring to avoid obstructing the air inlet and outlet of the yoke ventilation holes and form a good ventilation system.

[0012] The present application has the following beneficial effects:

[0013] 1. By improving the traditional single-disc rotor bracket, the present application uses two upper and lower discs to connect the yoke ring and the rotor central body, increasing the overall stiffness of the rotor bracket, which is applicable to large tubular turbine units with a larger rotor diameter and a longer rotor length, and solves the cracking problems of the traditional single-disc rotor bracket and the inclined vertical rib rotor bracket of large tubular turbine units.

[0014] 2. By arranging ventilation holes on the upper and lower discs, vertical ribs, and yoke ring components, the present application can form an effective ventilation path, significantly improving the heat dissipation effect.

[0015] 3. By arranging arcs at the stress concentration positions of the upper and lower discs, vertical ribs, and yoke ring components, the present application avoids fatigue failure caused by stress concentration. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0017] Figure 2 This is the sectional view of the overall structure of the present invention;

[0018] Figure 3 This is the front view of the overall structure of the present invention;

[0019] Figure 4 This is the detailed view of the upper disc structure of the present invention;

[0020] Figure 5 This is the detailed view of the lower disc structure of the present invention.

[0021] Explanation of the reference numerals in the figure:

[0022] 1 - Central body; 2 - Upper disc; 3 - Lower disc; 4 - Upper ring plate; 5 - Lower ring plate; 6 - Yoke ring; 7 - Vertical rib; 8 - Upper ring support plate; 9 - Lower ring stiffener; 10 - Upper ring stiffener; 11 - Ventilation holes on the upper disc; 12 - Ventilation holes on the lower disc; 13 - Yoke ventilation holes; 14 - Pole fixing holes; 15 - Brake ring. Detailed implementation manner

[0023] The following will describe the present application in detail with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary. The specific implementation manners described herein are only used to illustrate and explain the present invention, and are not intended to limit the scope of the present application. In addition, in the following description, the descriptions of well-known structures and technical common knowledge are omitted to avoid unnecessarily confusing the concepts of the present application.

[0024] Embodiment 1: Combining with the attached Figures 1-5 , the present application discloses a double-disc rotor bracket structure for a large bulb turbine unit, including: a central body 1, an upper disc 2, a lower disc 3, an upper ring plate 4, a lower ring plate 5, and a yoke ring 6; the central body 1, the upper disc 2, the lower disc 3, the upper ring plate 4, and the lower ring plate 5 are arranged inside the yoke ring 6, and the central body 1 is fixedly connected to the yoke ring 6 through the upper disc 2 and the lower disc 3; a plurality of ventilation holes 11 on the upper disc are uniformly arranged on the circumference of the upper disc 2, and a plurality of ventilation holes 12 on the lower disc are uniformly arranged on the circumference of the lower disc 3, and the circumferential arrangement positions of the ventilation holes 11 on the upper disc and the ventilation holes 12 on the lower disc correspond one by one to increase the air flow rate of the ventilation holes; a plurality of vertical ribs 7 are arranged between the upper disc 1 and the lower disc 2; a plurality of upper ring support plates 8 are arranged between the upper ring plate 4 and the upper disc 2.

[0025] Further, a plurality of upper ring stiffeners 10 are arranged below the upper ring plate 4, and a plurality of lower ring stiffeners 9 are arranged below the lower ring plate 5 to increase the overall stiffness of the rotor bracket.

[0026] Further, a brake ring 15 is fixedly arranged on the yoke ring 6, and the brake ring 15 is tightly connected to the upper ring plate 4.

[0027] Further, the yoke ring 6 is evenly provided with yoke ventilation holes 13 and pole fixing holes 14 in the circumferential direction. The yoke ventilation holes 13 are located between the poles, and the pole fixing holes 14 are located at the center lines of each pole. The circumferential numbers of the yoke ventilation holes 13 and the pole fixing holes 14 are the same as the number of poles, and the number in the axial direction is set according to the length of the yoke ring.

[0028] Further, arc-shaped notches are formed at the positions corresponding to the yoke ventilation holes 13 at the joints of the vertical ribs 7, the upper ring support plate 8 and the lower ring reinforcing rib 9 and the yoke ring 6 to avoid obstructing the air intake and exhaust of the yoke ventilation holes 13 and form a good ventilation system.

[0029] The above embodiments are only used to illustrate the technical concept and features of the present invention, and the purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A double-disc rotor bracket structure for a large bulb turbine unit, characterized in that: It includes a central body (1), an upper disc (2), a lower disc (3), an upper ring plate (4), a lower ring plate (5), and a yoke ring (6); the central body (1), the upper disc (2), the lower disc (3), the upper ring plate (4), and the lower ring plate (5) are arranged inside the yoke ring (6), and the central body (1) and the yoke ring (6) are fixedly connected through the upper disc (2) and the lower disc (3); a plurality of upper disc ventilation holes (11) are evenly arranged on the circumference of the upper disc (2), and a plurality of lower disc ventilation holes (12) are evenly arranged on the circumference of the lower disc (3), and the circumferential arrangement directions of the upper disc ventilation holes (11) and the lower disc ventilation holes (12) correspond one by one; a plurality of vertical ribs (7) are arranged between the upper disc (1) and the lower disc (2); a plurality of upper ring support plates (8) are arranged between the upper ring plate (4) and the upper disc (2).

2. The double-disc rotor support structure of the large bulb turbine unit according to claim 1, characterized in that: A plurality of upper ring stiffeners (10) are arranged below the upper ring plate (4), and a plurality of lower ring stiffeners (9) are arranged below the lower ring plate (5).

3. The double-disc rotor bracket structure of the large tubular turbine unit according to claim 2, characterized in that: A brake ring (15) is also fixedly arranged on the yoke ring (6), and the brake ring (15) is tightly connected to the upper ring plate (4).

4. The double-disc rotor bracket structure of the large bulb turbine unit according to claim 3, wherein: A plurality of yoke ventilation holes (13) and pole fixing holes (14) are evenly arranged on the circumference of the yoke ring (6), the yoke ventilation holes (13) are located between the poles, the pole fixing holes (114) are located at the center line of each pole, the circumferential numbers of the yoke ventilation holes (13) and the pole fixing holes (14) are the same as the number of poles, and the number in the axial direction is set according to the length of the yoke ring.

5. The double-disc rotor bracket structure of a large bulb turbine unit according to claim 4, characterized in that: Arc-shaped notches are opened at the positions corresponding to the yoke ventilation holes (13) at the joints of the vertical ribs (7), the upper ring support plates (8), and the lower ring stiffeners (9) and the yoke ring (6) to avoid obstructing the air intake and exhaust of the yoke ventilation holes 13.

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