Steam turbine generator stator

Abstract

The utility model provides a steam turbine generator stator. The steam turbine generator stator comprises a stator core, a stator winding, an epoxy filling layer, a stator end support and a covering paint layer. The stator iron core is located in a stator of the steam turbine generator and extends in the axial direction, the stator windings are embedded in grooves formed in the circumferential direction of the stator iron core and form stator winding end portions at the two ends of the stator iron core, and gaps are formed between the stator winding end portions and the end faces of the stator iron core. The stator end portion support is fixedly arranged on the end face of the stator core and located below the end portion of the stator winding, the lower side of the stator end portion support is fixedly connected with the end portion of the stator core, an epoxy filling layer used for filling a gap is arranged between the upper side of the stator end portion support and the end portion of the stator winding, and the stator end portion support is provided with a binding hole used for being connected with a binding belt. The binding tape is arranged in a surrounding mode in the circumferential direction of the end of the stator winding. The supporting stability of the end part of the stator winding can be improved, the fixing effect of the end part of the winding is enhanced, and looseness caused by vibration or thermal expansion in the operation process is reduced.

Description

Technical Field

[0001] This application relates to the field of steam turbine generator technology, and more particularly to a steam turbine generator stator. Background Technology

[0002] Steam turbine generators are crucial components of large thermal power generating units, their primary function being to convert the mechanical energy of a steam turbine into electrical energy. The stator of a steam turbine generator consists of a stator core, stator windings, and their end structures. The stability of the stator winding ends directly affects the generator's operational safety and long-term reliability. Because generators are subjected to complex electromagnetic forces, thermal stresses, and mechanical vibrations during operation, the fixing method and structural design of the stator winding ends have always been important research directions in the field of power generation equipment.

[0003] Currently, in the design and manufacture of steam turbine generators, the method of fixing the stator winding ends typically needs to meet the requirements of long-term stable operation while maintaining structural integrity under conditions such as load changes and temperature fluctuations. Some technical solutions provide fixing force through mechanical supports, combined with other additional measures, to adapt to the operating environment of the winding ends. However, with changes in grid operation modes, especially the increased operating time of thermal power units in deep peak-shaving mode, existing technologies still have certain shortcomings in fixing the stator winding ends, affecting the long-term reliability of the generator.

[0004] Due to the frequent changes in generator load caused by deep peak shaving operation, the temperature fluctuations at the stator winding ends are drastic. Differences in the coefficients of thermal expansion between different components can lead to localized loosening of the fixing structure due to stress concentration, thus affecting the stability of the winding ends. Therefore, improving the fixing method at the stator winding ends under deep peak shaving conditions to reduce the risk of loosening and improve its long-term stability is an urgent problem to be solved. Utility Model Content

[0005] This application provides a turbine generator stator to solve the problem of stator winding ends easily becoming loose under deep peak shaving conditions, thereby improving the long-term fixed reliability of stator winding ends.

[0006] This application provides a steam turbine generator stator, including a stator core, stator windings, an epoxy filler layer, a stator end bracket, and a cover paint layer;

[0007] The stator core is located inside the stator of the steam turbine generator and extends axially. The stator core is composed of multiple laminated laminations. The stator windings are embedded in slots arranged circumferentially within the stator core, forming stator winding ends at both ends of the stator core. A gap is formed between the stator winding ends and the end faces of the stator core. The stator end bracket is fixedly mounted on the end face of the stator core and located below the stator winding ends. The lower side of the stator end bracket is fixed to the end face of the stator core. The stator end bracket is provided with an epoxy filler layer for filling the gap between the upper side of the stator end bracket and the stator winding end. The stator end bracket is provided with a binding hole for connecting a binding strap. The binding strap is arranged around the circumference of the stator winding end. The stator winding end itself is connected by the wrapped binding strap. The outer surface of the stator winding end and the side surface of the stator end bracket facing the stator winding end are both provided with a sprayed coating.

[0008] In one optional embodiment, the stator end support includes multiple independent arc-shaped support blocks and multiple limiting protrusions distributed on each of the arc-shaped support blocks. The arc-shaped support blocks are arranged circumferentially around the end of the stator core and together form a ring structure. Each arc-shaped support block and each limiting protrusion are fixedly connected to the end of the stator core by fasteners. Multiple limiting protrusions are evenly spaced on the inner side of the arc-shaped support blocks. The limiting protrusions are arranged according to the circumferential spacing of the end of the stator winding.

[0009] In one optional embodiment, each of the arc-shaped support blocks of the stator end bracket is arranged circumferentially around the stator winding end, one end of each limiting boss is integrally connected to the inner side of the arc-shaped support block, the upper surface of the limiting boss is provided with a groove, and the epoxy filling layer is filled between the limiting boss and the stator winding end through the groove, the epoxy filling layer filling the groove to the extent that it is higher than the platform of the limiting boss.

[0010] In one alternative embodiment, the arc-shaped support block is fixed to the outer edge of the stator core by fasteners, the fasteners being bolts.

[0011] In one optional embodiment, the binding holes are respectively provided on the left and right sides of the limiting boss.

[0012] In one alternative embodiment, the binding strap is a fiber binding strap made of aramid fiber or glass fiber material.

[0013] In one alternative embodiment, the coating layer is an insulating anti-corona coating layer, which is made of corona-resistant epoxy resin or silicone coating material.

[0014] In one alternative embodiment, the epoxy filler layer is an epoxy resin filler layer.

[0015] Compared with the prior art, this application has the following beneficial effects:

[0016] 1. The turbine generator stator provided in this application has a stator end bracket fixed to the end face of the stator core and located below the stator winding end, forming a stable support structure. By fixing the stator end bracket to the end face of the stator core and forming a relatively stable support relationship with the winding end, it helps to reduce the offset of the winding end caused by external forces. In addition, the lower side of the stator end bracket is firmly connected to the stator core, further enhancing the rigidity of the overall structure. During long-term operation, it can better withstand the mechanical load and thermal stress of the stator winding end, reducing equipment damage and maintenance needs caused by loosening.

[0017] 2. In this application, the gap between the stator winding end and the stator end support is filled with an epoxy filler layer. This filler layer not only serves as a physical filler but also acts as a buffer during generator operation, reducing structural damage caused by stress concentration. In addition, by filling the gap between the stator winding end and the stator end support with an epoxy filler layer, the structure can maintain high integrity during thermal expansion and contraction, reducing connection loosening and mechanical fatigue problems caused by thermal expansion and contraction, and improving the long-term reliability of the winding end.

[0018] 3. This application uses a binding strap that wraps around the circumference of the stator winding end and is fixed through binding holes on the stator end bracket. Compared to the traditional single-point fixing method, this binding method can distribute the fixing force more evenly and improve the stability of the winding end. By using a wrap-around binding method, this application makes the fixing force on the stator winding end more balanced in different directions, reducing the risk of loosening of the binding structure due to long-term vibration and thermal expansion and contraction. Furthermore, the stator winding end and the side of the stator end bracket facing the winding end are coated with a covering paint layer. This paint layer can optimize the local electric field distribution, reduce local corona discharge during high-voltage operation of the winding end, making the long-term operation of the winding end more reliable and reducing safety hazards caused by insulation aging. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A front view of a steam turbine generator stator provided in an embodiment of this application;

[0021] Figure 2 This is a schematic diagram of the overall structure of a steam turbine generator stator provided in an embodiment of this application;

[0022] Figure 3 This is a schematic diagram of the structure of a stator end bracket provided in an embodiment of this application;

[0023] Figure 4 This is a structural schematic diagram of the arc-shaped support block and the limiting boss provided in an embodiment of this application;

[0024] Figure 5 A schematic diagram of a steam turbine generator stator after the stator windings have been removed, according to an embodiment of this application;

[0025] Figure 6 A schematic diagram of a limiting boss at the end of a stator winding according to an embodiment of this application;

[0026] Figure 7 This is a schematic diagram of a steam turbine generator stator without the stator end bracket installed, according to an embodiment of this application.

[0027] Figure 8 This is a schematic diagram of the structure of a stator core provided in an embodiment of this application;

[0028] Figure 9 This is a schematic diagram of the stator winding structure provided in an embodiment of this application.

[0029] Explanation of reference numerals in the attached figures:

[0030] 100-Stator core; 200-Stator winding; 210-Stator winding end; 300-Epoxy filler layer; 400-Stator end bracket; 401-Binding hole; 410-Arc-shaped bracket block; 411-Fastener; 420-Limiting boss; 421-Groove. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are also within the scope of protection of this application.

[0032] First, let me explain the terms used in this application:

[0033] Steam turbine generators are synchronous generators driven by steam turbines and are widely used in large-scale power generation systems such as thermal power plants and nuclear power plants. The high-speed rotation of the steam turbine drives the generator rotor, which in turn causes the stator to generate electrical energy. Steam turbine generators need to withstand high temperatures, high voltages, and strong electromagnetic forces, and their stability requirements are extremely high.

[0034] Stator: The stationary part of a steam turbine generator, its main function is to carry current through stator windings and generate a rotating magnetic field to achieve electrical energy output. Because the stator is subjected to electromagnetic forces and mechanical stresses, the stability of the stator structure directly affects the generator's performance.

[0035] Stator core: This is the main structural part of the stator, responsible for supporting the stator windings and providing a magnetic flux path. It is usually made of layers of high-permeability silicon steel sheets to reduce eddy current losses and improve motor efficiency. The stator core is cylindrical in shape and has winding slots evenly distributed around its circumference for housing the stator windings.

[0036] Deep peak shaving refers to the requirement for thermal power units to frequently adjust their generating power to fluctuate within a wide range when the power system experiences significant changes in load demand. Under deep peak shaving conditions, steam turbine generators need to frequently adjust their operation within a large load range, resulting in more drastic temperature changes at the stator winding ends.

[0037] Please see Figures 1-9 ,in, Figure 1 A front view of a steam turbine generator stator provided in an embodiment of this application; Figure 2 This is a schematic diagram of the overall structure of a steam turbine generator stator provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of a stator end bracket provided in an embodiment of this application; Figure 4 This is a structural schematic diagram of the arc-shaped support block and the limiting boss provided in an embodiment of this application; Figure 5 A schematic diagram of a steam turbine generator stator after the stator windings have been removed, according to an embodiment of this application; Figure 6 A schematic diagram of a limiting boss at the end of a stator winding according to an embodiment of this application; Figure 7 This is a schematic diagram of a steam turbine generator stator without the stator end bracket installed, according to an embodiment of this application. Figure 8 This is a schematic diagram of the structure of a stator core provided in an embodiment of this application; Figure 9 This is a schematic diagram of the stator winding structure provided in an embodiment of this application.

[0038] like Figures 1-9 As shown in the figure, this application provides a steam turbine generator stator, including a stator core 100, a stator winding 200, an epoxy filler layer 300, a stator end bracket 400, and a covering paint layer.

[0039] The stator core 100 is located inside the stator of the steam turbine generator and extends along the axial direction. The stator core 100 is composed of multiple laminated laminations.

[0040] The stator winding 200 is embedded in the circumferentially arranged slots of the stator core 100, forming stator winding ends 210 at both ends of the stator core 100. The stator winding is the current carrier of the generator, embedded in the slots of the stator core and connected to the external circuit. The stator winding typically uses copper conductors and insulation layers to withstand high voltage and high current. The stator winding may deform under the influence of high-frequency electromagnetic forces, temperature changes, and mechanical vibrations; therefore, the fixing method of the winding ends is crucial for the safe operation of the generator. The stator winding ends are extensions of the stator winding at both ends of the stator core. During operation, they are subjected to significant electromagnetic forces and thermal stresses, making them prone to deformation, loosening, or damage. Since the ends are not fixedly supported like the windings in the slots, additional fixing structures are required to ensure long-term stable operation.

[0041] In this embodiment, a gap is formed between the stator winding end 210 and the end face of the stator core 100; the stator end bracket 400 is fixedly disposed on the end face of the stator core 100 and located below the stator winding end 210, the lower side of the stator end bracket 400 is fixedly connected to the end of the stator core 100, and an epoxy filling layer 300 for filling the gap is provided between the upper side of the stator end bracket 400 and the stator winding end 210. Since the stator winding end 210 is affected by electromagnetic force and mechanical vibration during operation, if the support is unstable, it may cause a slight displacement of the winding end 210, which will affect the long-term stable operation of the generator. By fixing the stator end bracket 400 to the end face of the stator core 100 and forming a relatively stable support relationship with the stator winding end 210, it helps to reduce the offset of the stator winding end 210 caused by external force. The stator end support 400 can be made of a high-temperature resistant, high-strength metal material, selected from stainless steel, aluminum alloy, or high-strength, low-permeability alloy. Since the stator winding end 210 and the stator end support 400 are typically made of different materials, their coefficients of thermal expansion differ. Under high load operation, the stator winding end 210 may experience slight dimensional changes due to temperature variations. If the gap is not properly filled, it may lead to localized stress concentration, thereby affecting the stability of the winding end. This embodiment fills the space between the stator winding end 210 and the stator end support 400 with an epoxy filler layer 300, enabling the structure to maintain high integrity during thermal expansion and contraction, reducing connection loosening and mechanical fatigue problems caused by thermal expansion and contraction, and improving the long-term reliability of the winding end. Optionally, in this embodiment, the stator end bracket 400 is made of 17-4 PH stainless steel. 17-4 PH stainless steel possesses high strength, fatigue resistance, and good heat resistance, enabling it to withstand the mechanical load and thermal expansion stress of the stator winding end 210 for extended periods under deep peak-shaving conditions, thereby improving the fixing reliability and durability of the stator winding end 210. Furthermore, the stator end bracket 400 is provided with binding holes 401 for connecting binding straps. The binding straps are arranged around the circumference of the stator winding end 210 (the binding straps can be flexibly bound as needed; the binding straps are not shown in the figure). The stator winding end 210 itself is connected by the wrapped binding straps. In practical applications, binding straps can be wrapped around the stator winding end 210 as needed, based on the loosening condition and specific location after testing. The outer surface of the stator winding end 210 and the side surface of the stator end bracket 400 facing the stator winding end 210 are both provided with a sprayed coating.

[0042] This application relates to an improvement in the stator structure of a steam turbine generator, particularly enhancing the fixation and stability of the stator winding ends under deep peak shaving conditions. During operation, the stator winding ends are subjected to complex electromagnetic forces, thermal stresses, and mechanical vibrations. Especially under deep peak shaving conditions, frequent load adjustments lead to drastic temperature changes within the generator stator, and differences in the thermal expansion coefficients of different materials can cause uneven stress on the winding ends, potentially resulting in loosening, displacement, or even insulation damage. Traditional winding end fixing methods provide some support under standard operating conditions, but under prolonged temperature cycling, thermal expansion and contraction can cause some fixing structures to gradually loosen, reducing the mechanical stability of the winding ends and affecting the overall operational reliability of the generator. Therefore, this application addresses the issue of low reliability in winding end fixing by proposing the aforementioned improved stator winding end fixing structure. This structural optimization reduces the risk of loosening caused by deep peak shaving and extends the generator's stable operating life.

[0043] The turbine generator stator of this application embodiment employs an optimized fixing method for the stator winding ends. In the above embodiment, the stator end bracket 400 is fixed to the end face of the stator core 100 and located below the stator winding end 210, enabling the stator end bracket 400 to provide stable support for the stator winding end 210. Thus, when the stator winding end 210 undergoes thermal expansion or contraction due to temperature changes, the stator end bracket 400 provides reliable support, preventing displacement of the stator winding end 210 due to uneven stress. Furthermore, an epoxy filler layer 300 is filled between the stator winding end 210 and the stator end bracket 400. This filler layer not only fills the gap between the stator end bracket 400 and the stator end bracket 400 but also provides a buffering effect during temperature changes, reducing stress concentration caused by thermal expansion and helping to reduce the risk of structural loosening due to long-term operation.

[0044] Furthermore, to further enhance the fixing effect of the stator winding end 210, this embodiment of the application provides binding holes 401 on the stator end bracket 400 and binding straps are provided circumferentially on the stator winding end 210. This binding structure allows the stator winding end 210 to form a tighter constraint with the stator end bracket 400, thereby reducing the problem of loosening caused by vibration or temperature difference during long-term operation. At the same time, to enhance the surface protection capability of the stator winding end, a coating layer is sprayed on the outer surface of the stator winding end 210 and the side surface of the stator end bracket 400 facing the winding end. This coating layer can provide protection during long-term operation, improve the durability of the end structure, optimize the electrical environment of the winding end, and reduce the impact of external factors on the stability of the winding end. Through the above-mentioned optimized design, the stator structure provided in this application embodiment can effectively reduce the problem of stator winding end loosening caused by temperature changes during deep peak shaving operation of steam turbine generator, improve the long-term stability of the fixed structure, and reduce winding end displacement caused by mechanical vibration or thermal stress changes, thereby improving the overall operational reliability and service life of steam turbine generator.

[0045] In some embodiments, the stator end support 400 includes a plurality of independent arc-shaped support blocks 410 and a plurality of limiting protrusions 420 distributed on each arc-shaped support block 410. Each arc-shaped support block 410 is arranged circumferentially around the end of the stator core 100 and together forms a ring structure. Each arc-shaped support block 410 and each limiting protrusion 420 are fixedly connected to the end of the stator core 100 by fasteners 411. A plurality of limiting protrusions 420 are evenly spaced on the inner side of the arc-shaped support block 410. The limiting protrusions 420 are arranged according to the circumferential spacing of the stator winding end 210.

[0046] In the above embodiment, the stator end support 400 is composed of multiple independent arc-shaped support blocks 410, rather than an integral structure. The advantage of this design is that each arc-shaped support block 410 can be independently fixed to the end face of the stator core 100 and connected by fasteners 411. This allows the entire stator end support 400 to better adapt to the expansion or contraction of the stator winding end 210 due to temperature changes during operation. Traditional integral supports are prone to deformation under high-temperature environments due to uneven stress, leading to a decrease in fixing effectiveness. The segmented combined structure of this embodiment reduces the impact of overall deformation and improves long-term operational reliability. Furthermore, since the arc-shaped support blocks 410 are arranged circumferentially at intervals along the end of the stator core 100 and form a ring structure, installation is faster and more flexible, thus ensuring stable support for the stator winding end 210.

[0047] In addition, the multiple limiting bosses 420 distributed on each arc-shaped support block 410 in the above embodiments can improve the constraint force of the stator winding end 210 and reduce the risk of loosening. Traditional winding end support structures mainly rely on the overall contact of the bracket to provide fixing force. However, in this embodiment, multiple limiting bosses 420 are evenly spaced on the inner side of each arc-shaped bracket block 410, and the limiting bosses 420 are arranged according to the circumferential spacing of the stator winding end 210. This design ensures that the stator winding end 210 does not directly contact the overall surface of the stator end bracket 400, but is supported by the spaced support of multiple limiting bosses 420. This structure has two main advantages: First, the limiting bosses 420 can provide stronger mechanical constraint force at local positions, improving the fixing effect of the winding end in the circumferential direction; second, since the limiting bosses 420 are spaced apart, the small deformations of the winding end caused by thermal expansion during operation will not directly act on the entire stator end bracket 400, but will be distributed to multiple limiting bosses 420, reducing local stress concentration and thus reducing the risk of loosening of the winding end.

[0048] Furthermore, each arc-shaped support block 410 and the limiting boss 420 are fixedly connected to the end of the stator core 100 by fasteners 411, rather than by welding or bonding. The main advantage of using fasteners 411 is that installation and disassembly are more convenient, facilitating later maintenance. If a certain arc-shaped support block 410 of the stator end support 400 needs to be replaced due to aging or damage during long-term operation, the operator can directly remove the corresponding fastener 411 and replace the specific arc-shaped support block 410 without dismantling the entire support structure, improving the convenience of maintenance. In addition, the use of fasteners 411 ensures a more stable connection between each arc-shaped support block 410, and also facilitates fine-tuning according to the specific dimensions of the winding end during actual installation, avoiding the impact of installation errors on the support effect of the winding end.

[0049] As can be seen from the above, the improved measures adopted in this embodiment can make the support structure of the stator winding end 210 more reliable, thereby better adapting to the requirements of long-term operation under deep peak shaving conditions.

[0050] In some embodiments, each arc-shaped support block 410 of the stator end support 400 is arranged circumferentially around the stator winding end 210. One end of each limiting boss 420 is integrally connected to the inner side of the arc-shaped support block 410. A groove 421 is provided on the upper surface of the limiting boss 420. An epoxy filling layer 300 is filled between the limiting boss 420 and the stator winding end 210 through the groove 421. The filling of the groove 421 by the epoxy filling layer 300 satisfies the requirement of being higher than the platform of the limiting boss 420.

[0051] In the above embodiment, one end of each limiting boss 420 is integrally connected to the inner side of the arc-shaped support block 410. Compared with independently installed or additionally fixed limiting structures, this integrally molded design eliminates the need for additional connecting structures between the limiting boss 420 and the arc-shaped support block 410, thereby reducing the risk of loosening or falling off and improving the overall structural rigidity. During the long-term operation of the turbine generator, the stator end support 400 and the stator winding end 210 are subject to periodic thermal expansion and contraction and vibration. If each limiting boss 420 on the arc-shaped support block 410 is detached from the arc-shaped support block 410 and installed independently, it is easy to cause local loosening due to uneven stress, affecting the stability of the winding end. In this embodiment, the limiting boss 420 and the arc-shaped support block 410 are integrally molded, which can better transmit mechanical loads, reduce local stress concentration, and thus improve the stability of the winding end during long-term operation.

[0052] Furthermore, in this embodiment, the epoxy filler layer 300 is filled through the groove 421 on the upper surface of the limiting boss 420, which improves the uniformity and adhesion of the filling. Specifically, in this embodiment, a groove 421 is provided on the upper surface of the limiting boss 420, and the epoxy filler layer 300 is filled through this groove 421. This design allows the filler layer 300 to not only fill between the stator winding end 210 and the support structure, but also to penetrate into the groove 421 of the limiting boss 420, thereby enhancing the adhesion and bonding force of the epoxy filler layer 300. Traditional planar filling methods are prone to uneven filling material distribution in local areas due to the surface tension of the filler layer or the influence of the construction process, and even the problem of insufficient filling in some areas. However, the groove 421 in this embodiment provides a fixed filling space, allowing the epoxy filler layer 300 to adhere more firmly to the limiting boss 420 after curing, while the filling is more uniform, reducing voids and stress concentration, and improving the structural stability and long-term durability of the winding end.

[0053] Meanwhile, in the structural design of this embodiment, the height of the epoxy filler layer 300 after filling is higher than the platform surface of the limiting boss 420. This design allows the stator winding end 210 to directly contact the epoxy filler layer 300 during operation, rather than directly bearing the hard contact pressure from the limiting boss 420. Compared with the traditional rigid limiting structure, the structural design of this embodiment forms a buffer layer between the stator winding end 210 and the limiting boss 420. When the stator winding end 210 undergoes slight expansion or contraction due to temperature changes, the epoxy filler layer 300 can act as a buffer, reducing local stress concentration. Especially under deep peak shaving conditions, the temperature fluctuation of the winding end is large. If it directly contacts the rigid limiting boss 420, it is easy to generate local stress concentration due to thermal expansion and contraction, leading to mechanical fatigue or structural damage to the winding end. However, by setting the epoxy filler layer 300 higher than the limiting boss 420, this embodiment effectively disperses the stress at the winding end, thereby improving the long-term reliability and safety of the stator winding end 210.

[0054] In some embodiments, the arc-shaped support block 410 is fixed to the outer edge of the stator core 100 by fasteners 411, which are bolts. Compared to welding or riveting, bolted connections offer greater maintainability and reliability. Since the turbine generator stator experiences temperature fluctuations and mechanical vibrations during long-term operation, the fixing structure needs to possess good fatigue resistance and long-term stability. Bolted connections allow the arc-shaped support block 410 to be securely fastened to the outer edge of the stator core 100, and fine-tuning can be performed during installation to ensure that each arc-shaped support block 410 is evenly distributed in the circumferential direction, avoiding localized stress concentration due to manufacturing or installation errors. Furthermore, bolted connections facilitate the disassembly and replacement of the arc-shaped support block 410. If a support block becomes partially damaged or loose after long-term use, the individual support block can be replaced directly without large-scale dismantling of the entire support structure, improving maintenance convenience and reducing downtime.

[0055] In some embodiments, binding holes 401 are provided on the left and right sides of the limiting boss 420 respectively.

[0056] In this embodiment, binding holes 401 are provided on both the left and right sides of the limiting boss 420, making the fixing method of the binding strap reasonable and reliable, and further enhancing the stability of the winding end 210. During the operation of the steam turbine generator, the stator winding end 210 is subjected to the combined effects of electromagnetic force, thermal expansion stress, and mechanical vibration. Simply relying on the epoxy filler layer 300 cannot completely suppress the relative displacement of the winding end, so additional mechanical restraint is required by binding straps. In this embodiment, binding holes 401 are provided on both the left and right sides of the limiting boss 420, which means that the binding strap can connect to the limiting boss 420 through the binding holes 401 and form a wrap-around binding and fixing structure at multiple positions. This allows the binding strap to connect to each limiting boss 420 while simultaneously wrapping around and connecting the stator winding end 210, and the fixing force is evenly distributed at multiple points, thereby reducing the risk of loosening of the winding end 210 due to thermal expansion and contraction or long-term operation. In addition, the limiting boss 420 itself serves as a support structure, providing additional support force. The binding holes 401 on both sides also enable the binding strap to form a more reasonable winding path, thereby improving the durability of the binding structure.

[0057] In some embodiments, the cable ties are fiber cable ties made of aramid fiber or glass fiber material.

[0058] The binding straps are made of aramid fiber or glass fiber. Compared to traditional metal binding structures or ordinary fabric binding materials, these high-strength, heat-resistant fiber materials exhibit superior stability and durability under long-term operating conditions. The stator winding end 210 of the steam turbine generator operates in a high-temperature, high-electromagnetic-force environment. If the mechanical strength of the binding material is insufficient, long-term stress can easily lead to loosening or even breakage, thereby reducing the fixing effect of the winding end and affecting the reliability of the equipment. This embodiment selects fiber binding straps made of aramid fiber or glass fiber, which, on the one hand, possess high tensile strength, maintaining a tight state during long-term operation and are not prone to creep or loosening due to long-term stress; on the other hand, this material has excellent high-temperature resistance, and even under the high-temperature environment caused by long-term high-load operation of the generator, there will be no significant performance degradation. Furthermore, both aramid fiber and glass fiber materials have good electrical insulation properties. Compared to metal binding structures, these materials do not introduce additional electromagnetic interference or form induced circulating currents, thereby avoiding additional electrical losses and improving the electrical safety of the generator. Meanwhile, this type of fiber binding tape provides a certain elastic buffer during thermal expansion and contraction, reduces stress concentration, and further extends the service life of the binding structure.

[0059] In some embodiments, the coating layer is an insulating anti-corona coating layer, which is made of corona-resistant epoxy resin or silicone coating material.

[0060] In the above embodiments, the covering varnish layer is an insulating anti-corona varnish layer made of corona-resistant epoxy resin or silicone coating material. Compared with ordinary insulating coatings, this anti-corona varnish layer can more effectively reduce the partial discharge problem caused by uneven electric field distribution at the stator winding end 210 and its supporting structure under high-voltage operating conditions. Under high-voltage conditions, the stator winding end 210 and its surrounding structure are prone to local corona discharge due to electric field concentration effects. Long-term effects can lead to insulation aging, material carbonization, and even local damage, thereby affecting the operating stability and service life of the generator. This embodiment, by using a covering varnish layer made of corona-resistant epoxy resin or silicone coating material, ensures that the covering varnish layer still has high electrical strength and insulation performance under high-voltage and high-temperature environments, thereby effectively reducing partial discharge at the winding end in the supporting area and reducing the loss of the electrical insulation system. Furthermore, epoxy resin coatings possess high mechanical strength and wear resistance, maintaining stable adhesion during long-term operation and reducing the risk of coating peeling or aging. Silicone coatings, on the other hand, exhibit superior heat and moisture resistance, maintaining stable electrical insulation even under high humidity and high temperature conditions, thereby improving the long-term reliability of the generator stator end. Simultaneously, the uniform spraying of the coating layer onto the stator winding end 210 and the surface of the stator end support 400 facing the stator winding end 210 effectively optimizes the electric field distribution, reduces local electric field distortion, and improves the overall stability of the insulation system.

[0061] In some embodiments, the epoxy filler layer 300 is an epoxy resin filler layer. Compared to traditional air gap fillers or other filler materials such as silicone rubber or inorganic fillers, the epoxy resin filler layer 300 exhibits superior mechanical strength, heat resistance, and adhesion properties, effectively improving the structural stability between the stator winding end 210 and the stator end support 400. During long-term operation of the turbine generator, the stator winding end 210 undergoes slight expansion and contraction due to temperature changes and electromagnetic forces. If the filler material has poor adhesion, delamination or detachment may occur between the filler layer and the winding end or support, resulting in localized gaps and affecting the fixing effect. This embodiment uses epoxy resin as the filler material. After curing, this material forms a high-strength integrated structure, tightly filling the gap between the stator winding end 210 and the stator end support 400, reducing structural loosening caused by thermal expansion and contraction. In addition, the epoxy resin filler layer has excellent electrical insulation properties, which can reduce the local electric field intensity in the winding end area, reduce the risk of corona discharge, and improve the overall insulation level of the generator. At the same time, the epoxy resin filler layer has good heat resistance and can operate stably for a long time in high-temperature environments, avoiding cracking or peeling of the filler layer due to thermal aging, and ensuring the fixed reliability of the winding ends.

[0062] The working principle of the steam turbine generator stator provided in this embodiment is as follows:

[0063] During the operation of the turbine generator stator, the stator winding 200 is embedded in the slots of the stator core 100, forming stator winding ends 210 at both ends of the stator core 100. When the generator starts up and enters a stable operating state, the stator winding ends 210 may undergo slight mechanical displacement or stress changes under the action of electromagnetic force and thermal expansion effect. Therefore, effective fixing and support structures are needed to constrain the deformation of the stator winding ends 210 and provide long-term mechanical stability.

[0064] Therefore, in this embodiment of the turbine generator stator, a stator end bracket 400 is used as the support structure for the stator winding end 210. The stator end bracket 400 is composed of multiple arc-shaped bracket blocks 410 and is fixed to the outer edge of the stator core 100 by fasteners 411, forming a ring support structure. As the generator operates, the stator winding end 210 may be subjected to a certain pressure due to thermal expansion and contraction and electromagnetic vibration. The limiting bosses 420 evenly spaced on the inner side of the bracket blocks 410 play a rigid limiting role, restricting the radial movement of the stator winding end 210. Meanwhile, the epoxy filler layer 300 fills the groove 421 between the winding end 210 and the limiting boss 420. After curing, the epoxy filler layer 300 forms an integral structure, providing stable support. Furthermore, the height of the epoxy filler layer 300 is higher than the platform of the limiting boss 420, which plays a role in buffering and shock absorption, preventing stress concentration from occurring at the stator winding end 210 due to direct contact with the rigid structure during thermal expansion and contraction.

[0065] Furthermore, during long-term generator operation, the winding end 210 still requires further fixation to prevent gradual loosening due to prolonged stress. To this end, binding tape is arranged around the circumference of the winding end 210 and passes through the binding holes 401 on both sides of the limiting boss 420. The fastening fiber binding tape further constrains the stator winding end 210, improving its fixation strength. Since the binding tape is made of aramid fiber or glass fiber, it possesses high strength and high-temperature resistance, maintaining stable binding force over long periods in high-temperature and high-electromagnetic environments. Finally, during generator operation, the outer surface of the stator winding end 210 and the side of the stator end support 400 facing the winding end 210 are uniformly coated with a covering paint layer. This paint layer is made of corona-resistant epoxy resin or silicone coating material, which effectively optimizes the electric field distribution, reduces partial discharge, enhances insulation performance, and improves the long-term safety of the winding end.

[0066] In summary, the working process of the turbine generator stator in this embodiment of the application, through bracket support, filling and buffering, binding and fixing and insulation protection, can continuously provide effective support for the stator winding end 210 during generator operation, preventing it from loosening due to electromagnetic vibration and thermal expansion and contraction. At the same time, it can optimize the local electric field and improve the long-term stability and operational reliability of the stator.

[0067] The installation and usage method of the turbine generator stator in this embodiment is as follows:

[0068] 1. Install the stator core and stator windings

[0069] First, the stator core 100 is installed inside the turbine generator frame and extends axially to form a stable core support structure. Then, the stator windings 200 are embedded in the circumferentially arranged slots of the stator core 100, ensuring uniform distribution of the stator windings 200, and stator winding ends 210 are formed at both ends of the stator core 100. At this point, a certain gap exists between the stator winding ends 210 and the end faces of the stator core 100, providing space for subsequent filling and fixing.

[0070] 2. Install the stator end bracket and fix the limiting boss.

[0071] A stator end bracket 400 is installed around the stator winding end 210. The stator end bracket 400 uses multiple arc-shaped bracket blocks 410, and each arc-shaped bracket block 410 has a limiting boss 420 evenly spaced on its inner side. The arc-shaped bracket blocks 410 are fixed to the outer edge of the stator core 100 by fasteners 411 to form a ring structure. The limiting bosses 420 are also fixedly connected to the end of the stator core 100 by fasteners 411, and the limiting bosses 420 are arranged circumferentially around the stator winding end 210 so that they can play a limiting and supporting role in subsequent operation.

[0072] 3. Fill with epoxy filler layer

[0073] After the stator end bracket 400 is installed, an epoxy filler layer 300 is filled into the gap between the winding end 210 and the limiting boss 420. The epoxy filler layer 300 is filled through the groove 421 provided on the upper surface of the limiting boss 420 and forms an integrated structure after curing. The height of the filler layer must be higher than the platform surface of the limiting boss 420 to provide a buffering effect when the winding end 210 deforms due to thermal expansion and contraction, and to prevent mechanical stress from concentrating at the winding end.

[0074] 4. Bind the ends of the stator windings

[0075] To further strengthen the fixation of the stator winding end 210, binding holes 401 are provided on both sides of the limiting boss 420, and the binding tape passes through the binding holes 401 and is arranged around the circumference of the winding end 210, thereby providing stable mechanical constraint. The binding tape is made of aramid fiber or glass fiber material to ensure its durability and reliability in high temperature and high electromagnetic environment.

[0076] 5. Apply a coating of paint.

[0077] After mechanical fixing is completed, a coating layer is uniformly sprayed onto the outer surface of the stator winding end 210 and the side of the stator end support 400 facing the winding end 210. This coating layer is made of corona-resistant epoxy resin or silicone coating material, which can effectively optimize the electric field distribution, reduce local corona discharge, and improve insulation performance. During the spraying process, it is necessary to ensure that the coating thickness is uniform to achieve the best insulation effect.

[0078] 6. Further installation and commissioning

[0079] After completing the installation and fixing of the stator ends, the overall assembly of the generator needs to be completed. First, the stator is installed onto the generator frame, and its relative position to the rotor is adjusted to ensure that the stator-rotor clearance meets the design requirements, avoiding abnormal vibration or electromagnetic interference caused by deviation during operation. Then, the electrical terminals of the stator windings are connected, and the integrity of the stator winding ends 210 and their fixing structures is checked, ensuring that the binding straps are not loose, the epoxy filler layer 300 is not cracked, and the coating is not peeling or damaged.

[0080] After all components are installed, insulation tests, withstand voltage tests, and no-load test runs are performed on the generator to observe the fixing effect of the stator winding end 210 under different operating conditions. After confirming that the stator end bracket 400, the limiting boss 420, and the filling layer 300 are all stable and there is no abnormal displacement or loosening, the final encapsulation of the generator is completed.

[0081] After being put into operation, the binding and fixing status of the stator winding ends 210, the integrity of the filler layer, and the insulation effect of the covering varnish layer should be checked regularly to ensure that the stator winding ends will not loosen due to mechanical vibration or thermal expansion and contraction during long-term operation. If the binding tape is found to be loose, the filler layer is damaged, or the insulation layer is aged, it should be maintained or replaced in time to ensure the safe and stable operation of the generator and extend the service life of the equipment.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A turbogenerator stator characterized by, The stator core (100), the stator winding (200), the epoxy filling layer (300), the stator end support (400) and the covering paint layer are included. The stator core (100) is located inside the stator of a turbo-generator and extends along the axial direction, and is formed by stacking a plurality of laminations; the stator winding (200) is embedded in the circumferentially arranged slots of the stator core (100) and forms stator winding ends (210) at both ends of the stator core (100), and a gap is formed between the stator winding ends (210) and the end faces of the stator core (100); the stator end support (400) is fixedly arranged on the end face of the stator core (100) and located below the stator winding ends (210), the lower side of the stator end support (400) is fixedly connected with the end of the stator core (100), and the epoxy filling layer (300) for filling the gap is arranged between the upper side of the stator end support (400) and the stator winding ends (210); the stator end support (400) is provided with a binding hole (401) for connecting a binding belt, the binding belt is arranged in a circumferential direction of the stator winding ends (210), the stator winding ends (210) are connected by the winding binding belt, and the outer surface of the stator winding ends (210) and the side surface of the stator end support (400) facing the stator winding ends (210) are both provided with a covering paint layer formed by spraying.

2. The turbogenerator stator of claim 1, wherein, The stator end support (400) includes a plurality of independent arc-shaped support blocks (410) and a plurality of limiting bosses (420) distributed on each arc-shaped support block (410), each arc-shaped support block (410) is arranged circumferentially and spaced apart on the end of the stator core (100) and collectively surrounds to form an annular structure, each arc-shaped support block (410) and each limiting boss (420) are fixedly connected with the end of the stator core (100) by a fastener (411), and the inner side of each arc-shaped support block (410) is uniformly and spacedly provided with a plurality of limiting bosses (420), and the limiting bosses (420) are arranged according to the circumferential interval of the stator winding ends (210).

3. The turbogenerator stator of claim 2, wherein, Each arc-shaped support block (410) of the stator end support (400) is circumferentially arranged at the periphery of the stator winding ends (210), one end of each limiting boss (420) is integrally connected with the inner side of the arc-shaped support block (410), the upper surface of the limiting boss (420) is provided with a groove (421), the epoxy filling layer (300) is filled between the limiting boss (420) and the stator winding ends (210) through the groove (421), and the filling of the epoxy filling layer (300) to the groove (421) exceeds the top surface of the limiting boss (420).

4. The turbogenerator stator of claim 3, wherein, The arc-shaped support block (410) is fixed to the outer edge of the stator core (100) through the fastener (411), and the fastener (411) is a bolt.

5. A turbogenerator stator according to any one of claims 2 to 4, characterised in that, The limiting bosses (420) are respectively provided with the binding holes (401) on the left and right sides.

6. The turbogenerator stator of claim 5, wherein, The binding belt is a fiber binding belt made of aramid fiber or glass fiber material.

7. The turbogenerator stator of claim 1, wherein, The covering paint layer is an insulating anti-corona paint layer, and the anti-corona paint layer is made of a corona-resistant epoxy resin or a silicone coating material.

8. The turbogenerator stator of claim 1, wherein, The epoxy filling layer (300) is an epoxy resin filling layer.

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