CN108900025B - Composite construction cage stator tip rigidity reinforcing structure - Google Patents

Abstract

The invention discloses a rigidity reinforcing structure of a cage-shaped stator end part with a composite structure, which is characterized in that an annular reinforcing structure and a strip-shaped reinforcing structure are compounded to form the cage-shaped reinforcing structure at the end part of a stator winding, so that an upper layer stator bar, a lower layer stator bar and the cage-shaped reinforcing structure are tightly fixed together, and the purposes of obviously reinforcing the self integral rigidity of an involute part at the end part of a stator and enabling the integral vibration frequency range of the end part of the stator to reach the standard requirement are achieved.

Description

Composite construction cage stator tip rigidity reinforcing structure

The technical field is as follows:

the invention relates to the field of turbonators, in particular to a composite structure cage-shaped stator end rigidity reinforcing structure.

Background art:

the inherent vibration frequency of the stator end part of the turbonator has great influence on the safe operation of the generator, the full-speed turbonator stator of a 50Hz power supply system is acted by elliptical 100Hz electromagnetic force in the operation process, if the elliptical modal inherent frequency of the stator end part is equal to or close to 100Hz and the vibration response is large, the stator end part can resonate possibly, so that the abrasion of the whole winding end part is loose, the mechanical fatigue of a winding bar is caused, serious accident potential is caused, and the safe operation of a unit is damaged, therefore, the generator design should enable the overall elliptical inherent frequency of the stator end part to avoid the proper range of 100Hz as much as possible; however, the vibration characteristics of the end part of the stator cannot be accurately calculated by the current vibration analysis means; the stator end part assembly structure is complex, the end part shape and binding materials are also influenced by factors such as construction environment temperature, the inherent frequency of the end part is influenced by large uncertain factors, and the inherent frequency of the end part of the finished stator has large discreteness, so that the phenomenon that the vibration frequency of the end part of the stator does not meet the standard requirement often occurs in newly designed and repeatedly produced products; once the problem occurs, the problem is usually difficult to process and limited by the structure and the application environment, the binding structure at the end part of the generator stator cannot adopt a metal structure and cannot influence ventilation and cooling, the limitation condition on the design of the binding structure is very strict, once the construction is finished, the application space for temporarily changing the binding structure is limited and difficult to implement, the traditional remedial measure has little influence on the change of the vibration mode at the end part of the stator, generally only can change the natural frequency of 1-2Hz, and the elliptical vibration frequency at the end part cannot avoid the situation within the range of 95-110 Hz; the reason is that subsequent binding can only be attached to the surfaces of the upper layer stator bar and the lower layer stator bar, cannot form a tightening force, cannot tightly fix the upper layer stator bar and the lower layer stator bar together, cannot obviously enhance the integral rigidity, and cannot obviously change the elliptical vibration frequency of the end part;

in order to solve the problem, the origin of Europe is 'a radially rigid re-tensioning support structure', which comprises a support ring, a wedge, an insulating screw, a nut, the support ring and the like, the change of fastening force can be realized by adjusting the insulating screw and the nut, and the purpose of changing the elliptical vibration frequency of the end part of a stator is achieved, but the structure is complex, the manufacturing cost is high, the requirement on installation and adjustment is strict, the hidden troubles that the number of adjusting parts is large, the insulating screw and the nut are difficult to lock, the loosening and abrasion are easy to induce exist, and the application is limited; moreover, the scheme can only be applied to new design, the design structure must be thoroughly changed, and the scheme cannot be applied to the remediation of the existing design structure; in recent years, a method for improving the integral natural frequency of the end part of a generator by arranging an integral glass strand reinforcing ring at the outer diameter part of an insulating box to strengthen the integral structure integrity of the insulating box at the end part of a generator stator is adopted, and the applied patent proves that after the method is used for construction, the integral natural frequency of the end part of a stator winding is improved by about 8Hz, the effect is obviously better than that of the prior method, and partial unqualified products are successfully remedied; however, for products with excessive frequency deviation, the method still cannot meet the requirement of frequency change, and the integral natural frequency of the end part of the stator winding still falls within an unqualified range after construction, because the rigidity of the variable nose end has a limited effect on changing the rigidity of an involute part;

if the binding can be implemented at the involute part of the end part of the stator, the upper layer stator bar and the lower layer stator bar can be tightly fixed together, the effect of greatly improving the integral rigidity of the finished end part of the stator is achieved, and the purpose of greatly changing the integral natural frequency of the end part of the stator winding can be achieved; however, the problem is that the binding performed by the subsequent remedial measures cannot form enough tightening force, the effect of tightly fixing the upper layer stator bar and the lower layer stator bar is difficult to achieve, the integral rigidity cannot be obviously enhanced, and the elliptical vibration frequency of the end part cannot be obviously changed.

The invention content is as follows:

the invention discloses a cage-shaped stator end rigidity reinforcing structure with a composite structure, which has a structural form different from that of the prior art, and is formed by compounding two groups of annular reinforcing structures and a plurality of groups of strip-shaped reinforcing structures, wherein the cage-shaped reinforcing structures are formed at the end parts of stator windings, elastic acting force accumulated by a flat spring and a frustum-shaped non-metal elastic cushion is utilized to enable a binding structure implemented by subsequent remedial measures to form tightening force, so that an upper layer stator bar, a lower layer stator bar and the cage-shaped reinforcing structures are tightly fixed together, the self integral rigidity of an involute part is obviously enhanced, the elliptic vibration frequency of the end part is obviously changed, the integral rigidity of the end parts of the stator windings can be effectively improved, the integral natural frequency of the end parts of the stator windings of a generator is improved, and the integral vibration mode of the end parts of the stator windings of the, the generator is ensured to operate safely. The technical scheme of the invention is as follows: a cage-shaped stator end part rigidity reinforcing structure with a composite structure is formed by compounding two groups of annular reinforcing structures and a plurality of groups of strip-shaped reinforcing structures, wherein the two groups of annular reinforcing structures are respectively arranged at the start end of an involute on the end part of a generator stator and the tail end of the involute on the end part of the generator stator; the strip-shaped reinforcing structures are arranged and uniformly distributed along the bus direction of the frustum structure at the end part of the stator; the annular reinforcing structure consists of a reinforcing ring, a flat spring, a sector block, a conformal cushion and a binding band, wherein the reinforcing ring is provided with a ring groove, the flat spring and the sector block are arranged in the ring groove, the binding band penetrates through a corner through hole at the involute end of the stator bar to form a closed ring, and binding constraint is formed on a structure consisting of a lower layer stator bar, an interlayer conformal cushion, an upper layer stator bar, the conformal cushion, the sector block, the flat spring and the reinforcing ring; banded additional strengthening is by lower floor's splint, the form fit pad of lower floor, the form fit pad of upper strata, the upper strata splint, the nonmetal bullet pad of frustum shape, a cover plate, the wiring constitutes, the form fit pad of liner lower floor between lower floor's splint and the lower floor stator bar, the form fit pad of liner upper strata between upper strata splint and the upper stator bar, the upper surface of upper strata splint has the cavity, be used for holding the nonmetal bullet pad of frustum shape, the lower surface of apron has boss and the contact of the nonmetal bullet pad of frustum shape, the wiring passes the perforating hole that lower floor's stator bar and upper stator bar formed and constitutes the closed loop, to lower floor's splint, the form fit pad of lower floor's stator bar, the form fit pad between the layer, upper stator bar, the form fit pad on upper strata, the upper strata splint, the nonmetal bullet pad of frustum shape, the structure formation ligature restraint that the apron is constituteed.

The technical effects are as follows:

because the binding band passes through the stator bar involute tail end corner through hole to form a closed ring, the binding band can form a constraint fixation for the lower layer stator bar, the interlayer conformal cushion, the upper layer stator bar, the conformal cushion, the sector block, the flat spring and the reinforcing ring which are sequentially laminated, the binding band passes through the stator bar involute tail end corner through hole to form a closed ring to form a binding closed ring, so that the subsequent operation can be carried out after the stator winding is assembled, the stator bar involute tail end corner through hole has larger opening area than the through hole formed by the lower layer stator bar and the upper layer stator bar, the construction operation is more convenient, the binding band with larger cross section can be formed to form better constraint force, and because the flat spring is in a pressed bending deformation state, the lower layer stator bar, the interlayer conformal cushion and the reinforcing ring which are sequentially laminated, The upper layer stator bar, the conformal pad, the sector block, the flat spring and the reinforcing ring form an interaction force, the effect that the lower layer stator bar and the upper layer stator bar are firmly bound together is generated, the reinforcing ring, the upper layer stator bar and the lower layer stator bar can be tightly fixed together, and the conformal pad is padded between the upper layer stator bar and the sector block, so that stress concentration caused by local contact is avoided; the reinforcing ring is provided with a ring groove for accommodating the flat spring and the fan-shaped block, so that the flat spring and the fan-shaped block are prevented from escaping; the binding rope with a belt-shaped reinforcing structure penetrates through a through hole formed by a lower layer stator bar and an upper layer stator bar to form a closed ring, the lower layer clamping plate, the lower layer conformal pad, the lower layer stator bar, the interlayer conformal pad, the upper layer stator bar, the upper layer conformal pad, the upper layer clamping plate, the frustum-shaped nonmetal elastic pad and the cover plate can be sequentially laminated and fixed in a restraining way, the binding rope forms a binding closed ring by utilizing the through hole formed by the lower layer stator bar and the upper layer stator bar, the subsequent operation can be carried out after the stator winding is assembled, the binding rope is wound by glass tows impregnated with epoxy resin and is convenient to penetrate through the through hole, and the frustum-shaped nonmetal elastic pad is in a compressed state, so that the laminated lower layer clamping plate, the lower layer conformal pad, the lower layer stator bar, the interlayer conformal pad, the upper layer stator bar, the upper layer conformal pad, the frustum-shaped nonmetal elastic pad, The upper clamping plate, the frustum-shaped non-metal elastic pad and the cover plate form an interaction force, so that the effect that the lower stator bar and the upper stator bar are firmly bound together is achieved, the integrity of the frustum-shaped end part structure taking the lower stator bar and the upper stator bar as main bodies is improved, the integral rigidity is increased, and the integral vibration frequency is increased; the lower conformal gasket is arranged between the lower stator bar and the lower clamping plate, so that stress concentration caused by local contact is avoided; the upper-layer conformal cushion is arranged between the upper-layer stator bar and the upper-layer clamping plate in a lining mode, so that stress concentration caused by local contact is avoided; the upper surface of the upper layer clamping plate is provided with a cavity for containing the frustum-shaped non-metal elastic pad, so that the frustum-shaped non-metal elastic pad is prevented from escaping, the lower surface of the cover plate is provided with a boss which is contacted with the frustum-shaped non-metal elastic pad to generate pressing force on the frustum-shaped non-metal elastic pad, and the cover plate and the upper layer clamping plate are combined to facilitate construction operation, so that the frustum-shaped non-metal elastic pad is compressed to accumulate elastic force; because two groups of annular reinforcing structures and a plurality of groups of strip-shaped reinforcing structures are compounded, a cage-shaped reinforcing structure is formed at the end part of the stator winding, so that an upper layer stator bar, a lower layer stator bar and the cage-shaped reinforcing structure are tightly fixed together, the integral rigidity of an involute part is obviously enhanced, the elliptic vibration frequency of the end part is obviously changed, the integral rigidity of the end part of the stator winding can be effectively improved, the integral natural frequency of the end part of the stator winding of the generator is improved, the integral vibration mode of the end part of the stator winding of the generator meets the relevant standards and contract requirements, and the running safety of the generator is.

Description of the drawings:

fig. 1 is a schematic view of the application of the invention, and the sectional view is an involute part at the end part of a stator.

Fig. 2 is a sectional view taken along the line a of fig. 1.

Fig. 3 is a sectional view B-B of fig. 1.

Fig. 4 is a cross-sectional view taken along line C-C of fig. 1.

Fig. 5 is an axial view of a stator end constructed without the present invention.

Fig. 6 is an axial view of the stator end after construction using the present invention.

The specific implementation mode is as follows:

as shown in fig. 1, 2, 3 and 4, a cage-shaped stator end rigidity enhancing structure with a composite structure is formed by compositing two groups of annular reinforcing structures 1 and a plurality of groups of strip-shaped reinforcing structures 2, wherein the two groups of annular reinforcing structures 1 are respectively arranged at an involute starting end 3 at a generator stator end and an involute tail end 4 at a generator stator end; the strip-shaped reinforcing structures 2 are arranged and uniformly distributed along the bus direction of the frustum structure at the end part of the stator; the annular reinforcing structure 1 is composed of a reinforcing ring 5, a flat spring 6, a sector block 7, a conformal cushion 8 and a binding band 9, the reinforcing ring 5 is provided with a ring groove 10, the flat spring 6 and the sector block 7 are arranged in the reinforcing ring, the binding band 9 penetrates through a through hole 11 at the tail end corner of an involute of a stator bar to form a closed ring, binding constraint is formed on a structure composed of a lower layer stator bar 12, an interlayer conformal cushion 13, an upper layer stator bar 14, the conformal cushion 8, the sector block 7, the flat spring 6 and the reinforcing ring 5, the flat spring 6 is in a compressed bending deformation state, the flat spring 6 is arranged between the sector block 7 and the inner surface of the ring groove 10 of the reinforcing ring 5, and the conformal cushion 8 is arranged between the sector block; the belt-shaped reinforcing structure 2 comprises a lower layer clamping plate 15, a lower layer conformal pad 16, an upper layer conformal pad 17, an upper layer clamping plate 18, a frustum-shaped non-metal elastic pad 19, a cover plate 20 and a binding rope 21, wherein the lower layer conformal pad 16 is lined between the lower layer clamping plate 15 and a lower layer stator bar 12, the upper layer conformal pad 17 is lined between the upper layer clamping plate 18 and an upper layer stator bar 14, a cavity 22 is arranged on the upper surface of the upper layer clamping plate 18 and used for accommodating the frustum-shaped non-metal elastic pad 19, a boss 23 is arranged on the lower surface of the cover plate 20 and contacted with the frustum-shaped non-metal elastic pad 19, the binding rope 21 penetrates through a through hole formed by the lower layer stator bar 12 and the upper layer stator bar 14 to form a closed ring, and forms binding to the structure formed by the lower layer clamping plate 15, the lower layer conformal pad 16, the lower layer stator bar 12, the interlayer conformal pad 13, the upper layer stator bar 14, the upper layer, the frustum-shaped non-metal elastic pad 19 is in a compressed state;

because the binding band 9 passes through the stator bar involute tail end corner through hole 11 to form a closed ring, the binding band 9 can form a constraint fixation to the lower layer stator bar 12, the interlayer conformal pad 13, the upper layer stator bar 14, the conformal pad 8, the sector block 7, the flat spring 6 and the reinforcing ring 5 which are sequentially laminated, the binding band 9 passes through the stator bar involute tail end corner through hole 11 to form a closed ring to form a binding closed ring, so that the subsequent operation can be carried out after the stator winding is assembled, the stator bar involute tail end corner through hole 11 has a larger opening area than the through hole formed by the lower layer stator bar 12 and the upper layer stator bar 14, the construction operation is more convenient, the binding band 9 with a larger cross section can be formed, a better constraint force is formed, and the flat spring 6 is in a pressed bending deformation state, the lower layer stator bar 12 which is sequentially laminated under the resilience force and the constraint fixation effect of the binding, The interlayer conformal pad 13, the upper layer stator bar 14, the conformal pad 8, the fan-shaped block 7, the flat spring 6 and the reinforcing ring 5 form interaction force, the effect that the lower layer stator bar 12 and the upper layer stator bar 14 are firmly bound together is generated, the reinforcing ring 5, the upper layer stator bar 14 and the lower layer stator bar 12 can be tightly fixed together, the conformal pad 8 is padded between the upper layer stator bar 14 and the fan-shaped block 7, and stress concentration caused by local contact is avoided; the reinforcing ring 5 is provided with a ring groove 10 for accommodating the flat spring 6 and the sector 7 and preventing the flat spring 6 and the sector 7 from escaping;

the reinforcing ring 5 is wound by glass fiber strands impregnated with epoxy resin, the reinforcing ring has excellent mechanical property and insulating property after being cured, the flat spring 6 is made of stainless steel and can also be made of epoxy laminated glass cloth plates, the problems of heating and electromagnetic force caused by the electromagnetic field action of a generator stator are avoided, the sector block 7 is made of epoxy laminated glass cloth plates and has excellent mechanical property and insulating property, the conformal cushion 8 is made of polyester felts impregnated with epoxy resin and can be used for conformally filling irregular gaps between the upper layer stator bar 14 and the sector block 7, the sector block 7 and the upper layer stator bar 14 can be comprehensively and reliably transmitted with a pressure structure after being constructed and cured, the stress concentration caused by local contact is avoided, the number of the flat spring 6 and the sector block 7 can be selected to be 1/N of the number of stator slots, the value range of N is generally between two and four, the binding band 9 is a glass fiber cloth band impregnated with room temperature cured epoxy resin, the binding structure is in a soft state before curing, can be suitable for operation of penetrating through the through hole, adapts to the size of the structure, is tightly attached to the bound structure, is wound by multiple layers, and forms a closed ring with fastening strength after curing; the binding rope 21 of the belt-shaped reinforcing structure 2 penetrates through a through hole formed by the lower layer stator bar 12 and the upper layer stator bar 14 to form a closed ring, the lower layer clamping plate 15, the lower layer conformal pad 16, the lower layer stator bar 12, the interlayer conformal pad 13, the upper layer stator bar 14, the upper layer conformal pad 17, the upper layer clamping plate 18, the frustum-shaped non-metal elastic pad 19 and the cover plate 20 which are sequentially laminated can be restrained and fixed, the binding rope 21 forms a binding closed ring by utilizing the through hole formed by the lower layer stator bar 12 and the upper layer stator bar 14, so that the subsequent operation can be carried out after the stator winding is assembled, the binding rope 21 is wound by glass tows impregnated with epoxy resin and conveniently penetrates through the through hole, and the frustum-shaped non-metal elastic pad 19 is in a compressed state, so that the lower layer clamping plate 15, the lower layer conformal pad 16 and the upper layer stator bar 14 which are sequentially laminated under the resilience, The lower-layer stator bar 12, the interlayer conformal pad 13, the upper-layer stator bar 14, the upper-layer conformal pad 17, the upper-layer clamping plate 18, the frustum-shaped non-metal elastic pad 19 and the cover plate 20 form an interaction force, and an effect that the lower-layer stator bar 12 and the upper-layer stator bar 14 are firmly bound together is generated, so that the integrity of the frustum-shaped end part structure taking the lower-layer stator bar 12 and the upper-layer stator bar 14 as main bodies is improved, the integral rigidity is increased, and the integral vibration frequency is increased; the lower conformal pad 16 is padded between the lower stator bar 12 and the lower clamping plate 15 to avoid stress concentration caused by local contact; an upper-layer conformal cushion gasket 17 is arranged between the upper-layer stator bar 14 and the upper-layer clamping plate 18, so that stress concentration caused by local contact is avoided; the upper surface of the upper layer clamping plate 18 is provided with a cavity 22 for accommodating the frustum-shaped non-metal elastic pad 19, so that the frustum-shaped non-metal elastic pad 19 is prevented from escaping, the lower surface of the cover plate 20 is provided with a boss 23 which is contacted with the frustum-shaped non-metal elastic pad 19 to generate pressing force on the frustum-shaped non-metal elastic pad 19, the cover plate 20 and the upper layer clamping plate 18 are combined to facilitate construction operation, and the effect of enabling the frustum-shaped non-metal elastic pad 19 to be compressed to accumulate elastic force is achieved; the lower layer clamping plate 15, the upper layer clamping plate 18 and the cover plate 20 are made of laminated epoxy glass cloth plates, have the characteristics of excellent insulating property, no influence of end electromagnetic force, no electromagnetic loss and stable performance, and can not bring accident potential; the number of the strip-shaped reinforcing structures 2 can be determined according to the required adjustment frequency data, the more the installation number is, the more the overall stiffness improvement effect of the stator end part is obvious, the higher the vibration frequency increase value of the stator end part after construction is, the proper number is selected to enable the vibration frequency of the stator end part after construction to be increased to be within a qualified numerical range, the installation direction of the strip-shaped reinforcing structures 2 is that the long axis of the strip-shaped reinforcing structures is parallel to the bus direction of the frustum structure of the stator end part, the number of the frustum-shaped non-metal elastic cushions 19 and the number of the binding belts 21 are determined by specific structural requirements, the length of the stator end part and the number of the through holes are determined, if the number of the through holes is four, the number of;

because two groups of annular reinforcing structures 1 and a plurality of groups of strip-shaped reinforcing structures 2 are compounded, a cage-shaped reinforcing structure is formed at the end part of the stator winding, so that an upper layer stator bar 14, a lower layer stator bar 12 and the cage-shaped reinforcing structure are tightly fixed together, and the integral rigidity of an involute part is obviously enhanced; fig. 5 is a view of the end of a stator without the application of the solution according to the invention, and fig. 6 is a view of the end of a stator after application of the solution according to the invention, showing a specific application of eight sets of strip-like reinforcing structures 2.

Claims (1)

1. The utility model provides a compound structure cage stator tip rigidity reinforcing structure which characterized by: the generator stator end involute reinforced structure is formed by compounding two groups of annular reinforced structures (1) and a plurality of groups of strip-shaped reinforced structures (2), wherein the two groups of annular reinforced structures (1) are respectively arranged at the start end (3) of the generator stator end involute and the tail end (4) of the generator stator end involute; the strip-shaped reinforcing structures (2) are arranged and uniformly distributed along the bus direction of the frustum structure at the end part of the stator; the annular reinforcing structure (1) is composed of a reinforcing ring (5), a flat spring (6), a fan-shaped block (7), a conformal cushion (8) and a binding band (9), the reinforcing ring (5) is provided with a ring groove (10), the flat spring (6) and the fan-shaped block (7) are arranged in the reinforcing ring, the binding band (9) penetrates through a through hole (11) at the involute tail end corner of the stator bar to form a closed ring, binding constraint is formed on a structure consisting of a lower-layer stator bar (12), an interlayer conformal pad (13), an upper-layer stator bar (14), a conformal pad (8), a sector block (7), a flat spring (6) and a reinforcing ring (5), the flat spring (6) is in a pressed bending deformation state, the flat spring (6) is arranged between the sector block (7) and the inner surface of a ring groove (10) of the reinforcing ring (5), and the conformal pad (8) is arranged between the sector block (7) and the upper-layer stator bar (14); the belt-shaped reinforcing structure (2) is composed of a lower layer clamping plate (15), a lower layer conformal pad (16), an upper layer conformal pad (17), an upper layer clamping plate (18), a frustum-shaped non-metal elastic pad (19), a cover plate (20) and a binding rope (21), the lower layer conformal pad (16) is arranged between the lower layer clamping plate (15) and a lower layer stator bar (12), the upper layer conformal pad (17) is arranged between the upper layer clamping plate (18) and the upper layer stator bar (14), a cavity (22) is arranged on the upper surface of the upper layer clamping plate (18) and used for accommodating the frustum-shaped non-metal elastic pad (19), the lower surface of the cover plate (20) is provided with a boss (23) which is contacted with the frustum-shaped non-metal elastic pad (19), the binding rope (21) penetrates through holes formed by the lower layer stator bar (12) and the upper layer stator bar (14) to form a closed ring, and the lower layer clamping plate (15), the lower, The binding constraint is formed by a structure consisting of the interlayer conformal pad (13), the upper layer stator bar (14), the upper layer conformal pad (17), the upper layer clamping plate (18), the frustum-shaped non-metal elastic pad (19) and the cover plate (20), and the frustum-shaped non-metal elastic pad (19) is in a compressed state.

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