Slip ring of hydrogenerator

Abstract

The present invention discloses a collector ring for a hydrogenerator, which comprises a collector ring central body. The collector ring central body is characterized in that it includes an inner ring plate fixed on the large shaft of the generator. An upper fixed ring and a lower fixed ring which are insulated from each other are installed on the outer diameter of the inner ring plate through an insulating ring. An upper inner ring and a lower inner ring are rigidly connected to the upper fixed ring and the lower fixed ring respectively. An outer ring is provided in cooperation with the upper inner ring and the lower inner ring. The inward movement of the insulating layer eliminates the need for other external insulation treatments, reduces the cumbersome insulation installation processes such as adding insulating pads during the installation process of the collector ring, and reduces the maintenance work intensity of the collector ring. The design of "rigid positioning" of the upper and lower inner rings and the collector ring central body improves the installation positioning accuracy, ensures the roughness of the contact surface between the inner ring and the carbon brush during maintenance, reduces the form and position error, and improves the contact performance between the inner ring and the carbon brush. The split outer ring also avoids the risk of reducing the insulation of the generator excitation system due to the attachment of collector ring carbon powder.

Description

Technical Field

[0001] The present invention relates to generator technology, and particularly to a collector ring for a hydro-generator. Background Art

[0002] The collector ring is one of the important components of a hydro-generator set. During the operation of the unit, the collector ring rotates with the rotor, and the stationary carbon brush contacts the collector ring to transmit the excitation current to the rotor, enabling the generator to generate a rotating magnetic field and transmit electric energy to the power grid. Due to reasons such as design and manufacturing, the collector ring of some hydro-generator sets is installed between the thrust bearing and the upper guide bearing. Because of its relatively simple structure and convenient design and installation, it has been widely used. However, due to the compact installation position, it directly affects the maintenance of components such as the upper guide bearing of the generator. During each major overhaul of the unit, the collector ring must be disassembled in sections to carry out corresponding work. Moreover, since the old collector ring is fixed with insulating screws, insulating sleeves, etc., it is impossible to set positioning pins, resulting in poor positioning accuracy. It is very difficult to ensure the coaxiality requirement between the collector ring and the rotation center of the large shaft after reinstallation after disassembly in sections. Therefore, a common method is to design a bracket in the collector ring chamber to install a turning tool holder to turn the collector ring on-site to ensure the coaxiality after installation of the collector ring. However, the turning work is time-consuming and laborious, the operating space for the turning personnel is narrow, and there are serious potential safety hazards to personal injury and death; moreover, limited by the accuracy of the temporary tool holder, it is very difficult to ensure the surface roughness accuracy of the turned collector ring, resulting in a large amount of carbon brush wear and excessive carbon powder accumulation, thus affecting the insulation performance of the unit; in addition, this turning scheme also requires the hydro-generator set to maintain a low rotational speed for a long time, affecting the operation safety, and there has been an accident of burning of the upper guide bearing bush of the unit during the turning process. Summary of the Invention

[0003] The purpose of the present invention is to solve the above problems and provide a collector ring for a hydro-generator, which has the characteristics of meeting the requirements of insulation specifications, streamlining the installation process of the collector ring, and having high and fast positioning accuracy.

[0004] The above technical problems of the present invention are mainly solved by the following technical solutions: A collector ring for a hydro-generator, including a collector ring central body, characterized in that the collector ring central body includes an inner ring plate fixed on the large shaft of the generator, and an upper fixed ring and a lower fixed ring insulated from each other are installed on the outer diameter of the inner ring plate through an insulating ring. Rigidly connected to the upper fixed ring and the lower fixed ring are an upper inner ring and a lower inner ring respectively, and an outer ring is provided in cooperation with the upper inner ring and the lower inner ring.

[0005] In the foregoing collector ring for a hydro-generator, preferably, the outer ring is of a split structure, including an upper outer ring and a lower outer ring arranged symmetrically about the center of the large shaft of the generator and offset up and down.

[0006] In the aforementioned collector ring of a hydro-generator, preferably, positioning holes are respectively provided on the plates of the upper fixing ring and the lower fixing ring along the same diameter, and reference holes matching the positioning holes are respectively provided in the upper inner ring and the lower inner ring.

[0007] In the aforementioned collector ring of a hydro-generator, preferably, a shoulder is provided on the outer diameter of the inner ring plate to position the insulating ring through the shoulder; a shoulder is also provided on the outer diameter of one end of the insulating ring to limit the axial degree of freedom of the lower fixing ring through the shoulder.

[0008] In the aforementioned collector ring of a hydro-generator, preferably, the annular single-sided longitudinal sections of the upper fixing ring and the lower fixing ring are both L-shaped structures, and they are respectively connected to the inner ring plate through a set of radial bolts, and insulating sleeves and insulating washers are provided for matching with the radial bolts.

[0009] In the aforementioned collector ring of a hydro-generator, preferably, the upper inner ring and the lower inner ring are both split structures, that is, they are composed of two half rings, namely the first half ring and the second half ring.

[0010] In the aforementioned collector ring of a hydro-generator, preferably, a number of uniformly distributed tooth-shaped connecting piers are provided in the inner circles of the upper inner ring and the lower inner ring, and the tooth-shaped connecting piers cooperate with the upper fixing ring and the lower fixing ring.

[0011] In the aforementioned collector ring of a hydro-generator, preferably, the tooth-shaped connecting piers in the upper inner ring and the lower inner ring are arranged in a staggered manner when cooperating with the upper fixing ring and the lower fixing ring.

[0012] In the aforementioned collector ring of a hydro-generator, preferably, fixing parts for positioning and passing through the shaft lead wires are symmetrically distributed around the center point in the upper inner ring and the lower inner ring.

[0013] In the aforementioned collector ring of a hydro-generator, preferably, both the upper fixing ring and the lower fixing ring are split structures. The upper fixing ring is composed of two parts, namely the left half ring and the right half ring, and the connection part between the upper fixing ring and the inner ring plate is a concave arc screw seat.

[0014] The working principle of this technical solution is: a current transmission device that transmits the external exciting current to the rotating magnetic pole of the generator. During the operation of the unit, the large shaft of the water turbine drives the central body of the collector ring and the upper and lower inner rings of the collector ring to rotate clockwise together with the large shaft. The external exciting current is transmitted to the upper and lower inner rings of the collector ring through the carbon brushes installed on the upper and lower outer rings, and is transmitted to the rotating magnetic pole of the generator through the exciting shaft lead wires installed on the upper and lower inner rings, thus completing the exciting process of the generator.

[0015] This solution sets the insulation layer inside the center body of the collector ring, moves the insulation inward and solidifies it, which is more conducive to the stability of the overall insulation of the collector ring; and optimizes its connection and fixing structure, and pre-sets positioning pins with high-precision matching, which improves the positioning accuracy of the collector ring while meeting the insulation technical requirements. This solution solves the problem that the original collector ring must be turned on the unit after disassembly and assembly; it can be completely processed by ordinary machine tools, so that the working surface accuracy of the collector ring is completely guaranteed, thereby effectively controlling the wear of the carbon brush and reducing the accumulation of carbon powder.

[0016] This scheme includes the upper and lower inner rings (Note: the upper inner ring and the lower inner ring are collectively referred to as the same below), the outer ring, and the outer ring base arranged outward with the central body of the collector ring. The upper and lower inner rings are fixed on the main shaft of the hydro-turbine generator through the central body of the collector ring and rotate with the main shaft of the generator. The carbon brush holder assembly is installed on the outer ring, and the carbon brushes on the carbon brush holder assembly are used to transmit the excitation current required by the generator set to the upper and lower inner rings, and the excitation current is transmitted to the generator poles through the excitation through-shaft lead to complete the excitation cycle of the unit; the upper and lower inner rings and the central body of the collector ring are insulated from each other to meet the requirements of the collector ring to transmit the excitation current and to insulate from the ground.

[0017] This scheme specifically studies the center body of the collector ring, and preferably designs an inner ring plate to match the main shaft of the generator, and then sets an upper fixing ring and a lower fixing ring outward. In addition, the inner ring plate, the upper fixing ring, the lower fixing ring, and the upper fixing ring and the lower fixing ring are separated by insulating rings, so that the insulating layer is completely hidden inside the center body of the collector ring, and then the upper and lower inner rings are rigidly connected to the upper fixing ring and the lower fixing ring respectively.

[0018] In order to avoid removing the center body when disassembling and assembling the guide bearing on the generator, this scheme sets the annular single-sided longitudinal section of the upper fixing ring and the lower fixing ring as an L-shaped structure when designing the center body of the collector ring. On the premise of ensuring the structural strength, it is connected to the inner ring plate by a set of radial bolts and an insulating layer is added. This allows the scheme to reduce the size of the center body of the collector ring and make it into an integral mutually insulated structure, thereby extending the maintenance period of the collector ring. If the insulation meets the maintenance requirements, disassembly and inspection can be avoided, thereby reducing the maintenance workload of the unit and improving work efficiency.

[0019] Furthermore, the outer ring of the collector ring is designed as a split structure, that is, an upper outer ring and a lower outer ring, which are symmetrical about the center of the generator shaft and staggered up and down, thereby reducing the risk of reducing the insulation of the generator excitation system due to the adhesion of carbon powder to the collector ring, and changing the original structural method of connecting the upper and lower outer rings of the collector ring into a whole with an insulating plate, thereby eliminating the possibility of reducing the insulation resistance of the upper and lower outer rings of the collector ring due to carbon powder contamination, thereby improving the overall safety margin of the generator excitation system.

[0020] Positioning holes are ingeniously arranged on the plate bodies of the upper and lower fixing rings on the same diameter, and reference holes are also set in the upper and lower inner rings. At the same time, axial positioning is carried out through shoulders on the outer diameters of the inner ring plates and insulating rings to limit the axial freedom of the lower fixing ring. Considering various factors, it is ensured that all components can be corresponding one by one immediately in any disassembly and assembly state, increasing the installation and positioning accuracy of the collector ring central body and the upper and lower inner rings, reducing the coaxiality deviation between the rotating center of the unit before and after maintenance, improving the contact quality and conductivity between the carbon brushes of the electric ring and the upper and lower fixing rings of the collector ring, effectively reducing the wear of the carbon brushes, and improving the safe and reliable performance of the unit operation.

[0021] According to the principle of positioning holes and reference holes in this solution, the upper inner ring, lower inner ring, upper fixing ring, and lower fixing ring are all designed with split structures. Even in a complex environment, installation and maintenance operations can be carried out quickly.

[0022] In terms of details, all components in this solution are optimized. Tooth-shaped connection piers are arranged on the inner rings of the upper and lower inner rings. When the tooth-shaped connection piers of the two fixing rings are matched with the upper and lower fixing rings, they are arranged in a staggered manner, which not only reduces their own weight and ensures the strength of the components, but also facilitates the maintenance of the collector ring and the "restoration" of the collector ring, reducing the maintenance workload of the collector ring.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] The design of the collector ring central body moves the insulating layer inward, eliminating the need for other external insulation treatments, reducing the cumbersome insulation installation procedures such as adding insulating pads during the installation process of the collector ring, reducing the maintenance work intensity of the collector ring, and improving the maintenance work efficiency; the design of "rigid positioning" of the upper and lower inner rings and the collector ring central body greatly improves the installation and positioning accuracy, ensures the roughness of the contact surface between the inner ring and the carbon brush during maintenance, reduces the geometric errors such as coaxiality and roundness, and improves the contact performance between the inner ring and the carbon brush; the design of the split outer ring also avoids the risk of reducing the insulation of the generator excitation system due to the attachment of carbon powder on the collector ring.

[0025] This solution is applicable to all occasions where the design and installation of the collector ring are unreasonable and the maintenance workload is large. The characteristics of accurate positioning of this structure can be utilized to complete the overall processing task of the collector ring on standard processing equipment, improving the processing quality of the collector ring while making the manufacturing and maintenance of the collector ring more convenient and flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic structural diagram of an installation state of the present invention.

[0027] Figure 2 is Figure 1 a partial enlarged structural diagram at M of

[0028] Figure 3It is a schematic structural diagram of the collector ring central body of the present invention.

[0029] Figure 4 It is Figure 3 a sectional view taken along the B-B direction.

[0030] Figure 5 It is a schematic structural diagram of the assembled state of the inner ring of the present invention.

[0031] Figure 6 It is Figure 5 a sectional view taken along the A-A direction.

[0032] Figure 7 It is a schematic structural diagram of the installation of the outer ring of the present invention.

[0033] Figure 8 It is a schematic structural diagram of the insulating sleeve of the present invention.

[0034] Figure 9 It is a schematic structural diagram of the inner ring of the present invention.

[0035] Figure 10 It is a schematic structural diagram of the upper fixing ring of the present invention.

[0036] Figure 11 It is an auxiliary view of the positional relationship between the upper outer ring and the lower outer ring of the present invention.

[0037] In the figure: 1. lower platform, 2. generator large shaft, 3. collector ring central body, 301. upper fixing ring, 301a. left half ring, 301b. right half ring, 301c. concave arc screw seat, 301d. positioning hole, 302. lower fixing ring, 303. radial bolt, 304. insulating washer, 305. insulating sleeve, 306. insulating ring, 307. inner ring plate, 308. combined screw group, 4. inner ring, 401. upper inner ring, 402. lower inner ring, 4a. first half ring, 4b. second half ring, 4c. splicing cap group, 4d. reference hole, 4e. tooth-shaped connection pier, 5. external power supply lead wire, 6. outer ring, 601. upper outer ring, 602. lower outer ring, 603. carbon brush holder assembly, 604. adjusting screw, 605. insulating component, 606. outer ring base, 7. through-shaft lead wire, 8. upper platform. Detailed implementation manners

[0038] The technical solution of the present invention will be further specifically described below through embodiments and in conjunction with the drawings.

[0039] Refer to Figures 1 to 4 , a collector ring of a hydrogenerator in this embodiment mainly consists of a collector ring central body 3, an inner ring 4, and an outer ring 6.

[0040] Among them, the collector ring central body 3 includes an inner ring plate 307 fixed on the large shaft 2 of the generator. An insulating ring 306 is sleeved on the outer diameter of the inner ring plate 307. A fixed ring 301 and a lower fixed ring 302 are installed outside the insulating ring 306, and the fixed ring 301 and the lower fixed ring 302 are separated by an insulating washer. The inner ring plate 307 is of a sleeve structure, and a shoulder is provided on the outer diameter of its lower end to position the insulating ring 306 through this shoulder; a shoulder is also provided on the outer diameter of the lower end of the insulating ring 306 to limit the axial freedom of the lower fixed ring 302 through this shoulder. Two groups of upper and lower screw holes are provided around the inner ring plate 307. Correspondingly, through holes matching the two groups of screw holes are provided on the insulating ring 306, as Figure 8 shown. The upper fixed ring 301 and the lower fixed ring 302 have the same structure and are both split structures. Taking the upper fixed ring 301 as an example, it consists of two parts, a left half ring 301a and a right half ring 301b, and is connected by a combined screw group 308. The connection part between the upper fixed ring 301 and the inner ring plate 307 is a concave arc screw seat 301c, and fasteners are radially inserted. The annular single-sided longitudinal sections of the upper fixed ring 301 and the lower fixed ring 302 are both L-shaped structures, as Figure 10 shown. The two are respectively connected to the inner ring plate 307 through a group of radial bolts 303, and insulating sleeves 305 and insulating washers 304 are installed when matching with the radial bolts 303.

[0041] Positioning holes 301d are respectively provided on the plate bodies of the upper fixed ring 301 and the lower fixed ring 302 on the same diameter. The specific method is: two positioning holes 301d are arranged along the center line of the combination of the left half ring 301a and the right half ring 301b. The combined upper fixed ring 301 and lower fixed ring 302 are respectively provided with 8 connection holes for rigidly fixing the inner ring 4.

[0042] The inner ring 4 is composed of an upper inner ring 401 and a lower inner ring 402 arranged in parallel. Both the upper inner ring 401 and the lower inner ring 402 are split structures, that is, they are composed of two half rings, a first half ring 4a and a second half ring 4b, as Figure 9 shown. The two half rings are combined into one body through a combined cap group 4c. Eight evenly distributed tooth-shaped connection piers 4e are provided in the inner circles of the upper inner ring 401 and the lower inner ring 402. The tooth-shaped connection piers 4e cooperate with the 8 connection holes on the upper fixed ring 301 and the lower fixed ring 302. During assembly, the tooth-shaped connection piers 4e in the upper inner ring 401 and the lower inner ring 402 are arranged in a staggered manner with the upper fixed ring 301 and the lower fixed ring 302, so that the positions of the connection holes are staggered. See Figure 5 、 Figure 6 . Positioning hole configuration: In the upper inner ring 401 and the lower inner ring 402, reference holes 4d matching the positioning holes 301d in the upper and lower fixed rings are respectively provided along the combination line of the two half rings.

[0043] In addition, in the upper inner ring 401 and the lower inner ring 402, fixing parts for positioning and passing through the lead wire 7 are symmetrically arranged with respect to the center point.

[0044] Matched with the upper inner ring 401 and the lower inner ring 402 is the outer ring 6. The outer ring 6 is of a split structure and includes an upper outer ring 601 and a lower outer ring 602 that are symmetrically arranged with respect to the center of the generator main shaft 2 and are offset up and down. See Figure 7 , Figure 11 . Carbon brush holder assemblies 603 are respectively provided at the positions of the upper outer ring 601 and the lower outer ring 602. The upper outer ring 601 and the lower outer ring 602 are respectively connected to the bottom ends of their respective adjusting screws 604. The top ends of the adjusting screws 604 are connected to the outer ring base 606 through insulating assemblies 605. The outer ring base 606 is fixed on the upper platform 8. The carbon brush holder assemblies 603 are connected to the external power supply lead wire 5.

[0045] During maintenance and installation: Since the collector ring central body 3 (including the inner ring plate 307, the upper fixing ring 301, and the lower fixing ring 302, and the relevant assembly of these components is completed in the processing factory to achieve full-circle machining and fully ensure the accuracy) is fixed on the generator main shaft 2 between the lower platform 1 and the upper platform 8 in advance, after on-site installation, its structure forms an integral body with the generator main shaft 2. And insulation treatment is carried out between the upper fixing ring 301, the lower fixing ring 302, and the inner ring plate 307. The upper inner ring 401 and the lower inner ring 402 with a split structure are "rigidly connected" through various forms such as standard multi-hole bolts and reference positioning holes, making it easy to disassemble and reinstall the upper inner ring 401 and the lower inner ring 402 correctly.

[0046] The above embodiments are illustrative of the present invention, not limiting the present invention. For example, the inner ring plate 307 and the generator main shaft 2 are provided as an integral structure, etc. Any method, process, structure, etc. obtained by simple transformation of the present invention all fall within the protection scope of the present invention.

Claims

1. A collector ring for a hydrogenerator, comprising a collector ring central body (3). Characterized in that the collector ring central body includes an inner ring plate (307) fixed on the large shaft (2) of the generator. On the outer diameter of the inner ring plate, an upper fixed ring (301) and a lower fixed ring (302) which are insulated from each other are installed through an insulating ring (306). Rigidly connected to the upper fixed ring and the lower fixed ring are an upper inner ring (401) and a lower inner ring (402) respectively. An outer ring (6) is provided in cooperation with the upper inner ring and the lower inner ring. The outer ring is of a split structure, including an upper outer ring (601) and a lower outer ring (602) which are symmetrically arranged about the center of the large shaft of the generator and are vertically offset. Carbon brush holder assemblies (603) are respectively provided at the positions of the upper outer ring and the lower outer ring. An external power supply lead (5) is connected to the position of the carbon brush holder assembly. A number of uniformly distributed tooth-shaped connecting piers (4e) are provided in the inner circles of the upper inner ring and the lower inner ring. The tooth-shaped connecting piers cooperate with the upper fixed ring (301) and the lower fixed ring (302). And when the tooth-shaped connecting piers in the upper inner ring and the lower inner ring cooperate with the upper fixed ring and the lower fixed ring, they are arranged in a staggered manner.

2. The collector ring for a hydrogenerator according to claim 1, Characterized in that, positioning holes (301d) are respectively provided on the plate bodies of the same diameter of the upper fixed ring (301) and the lower fixed ring (302). Reference holes (4d) which cooperate with the positioning holes are respectively provided in the upper inner ring (401) and the lower inner ring (402).

3. The collector ring for a hydrogenerator according to claim 1, Characterized in that, a shaft shoulder is provided on the outer diameter of the inner ring plate (307) to position the insulating ring (306) through the shaft shoulder. A shaft shoulder is also provided on the outer diameter of one end of the insulating ring to limit the axial degree of freedom of the lower fixed ring (302) through the shaft shoulder.

4. The collector ring for a hydrogenerator according to claim 1, Characterized in that, the annular single-side longitudinal sections of the upper fixed ring (301) and the lower fixed ring (302) are both of L-shaped structures and are respectively connected to the inner ring plate (307) through a set of radial bolts (303). An insulating sleeve (305) and an insulating washer (304) are provided in cooperation with the radial bolts.

5. The collector ring for a hydrogenerator according to claim 1, Characterized in that, the upper inner ring (401) and the lower inner ring (402) are both of split structures with split halves, that is, they are composed of two half rings, namely a first half ring (4a) and a second half ring (4b).

6. The collector ring for a hydrogenerator according to claim 1 or 5, Characterized in that, fixed parts for positioning and passing through the shaft lead (7) are symmetrically distributed about the center point in the upper inner ring (401) and the lower inner ring (402).

7. The collector ring for a hydrogenerator according to claim 1, Characterized in that, the upper fixed ring (301) and the lower fixed ring (302) are both of split structures with split halves. The upper fixed ring is composed of two parts, namely a left half ring (301a) and a right half ring (301b). The connection part between the upper fixed ring and the inner ring plate (307) is a concave arc screw seat (301c).

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