CN216959442U - Stator structure of generator set - Google Patents

Abstract

The embodiment of the application provides a generating set stator structure relates to hydraulic generator operation on-line monitoring technical field, can be in real time to the stator iron core in the iron core piece whether compress tightly each other and detect, and the concrete scheme is: the method comprises the following steps: a stator core; a fastening assembly for maintaining the stator core in a compressed state; and the force measuring assembly comprises a pressure sensor, and the pressure sensor is arranged between the stator core and the fastening assembly and is used for measuring the relative pressure value between the stator core and the fastening assembly. The generator set stator structure provided by the embodiment can detect the stator core compression state in real time, and does not need to arrange a corresponding detection assembly on the iron core punching sheet, so that the influence on the stator core is avoided; the detection device is positioned at the outer side of the stator core, so that the interference of the stator core is less, and the measurement resolution is high; the generating set stator structure that this embodiment provided all adopts the nested mode of assembly part, and is integrative high.

Description

Stator structure of generator set

Technical Field

The application relates to the technical field of on-line monitoring of operation of hydraulic generators, in particular to a stator structure of a generator set.

Background

The stator core is formed by overlapping a plurality of core punching sheets, and under the state that the core punching sheets are not compressed, the core punching sheets can be displaced in a plurality of directions by electromagnetic force and mechanical force when the water turbine generator set works, the core punching sheets are easy to damage, meanwhile, the loosened core punching sheets can also touch and rub the penetrating screw rod, an insulating layer on the penetrating screw rod is damaged, a short circuit occurs, and the burning accidents of the screw rod and the contacted core punching sheets are caused; even more serious accidents can be caused by cutting the slot part insulation of the stator bar; therefore, information about whether the plurality of iron core laminations of the stator iron core are in compression or not needs to be obtained in real time.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a stator structure of a generator set and a stator measuring point arrangement method, which can detect whether iron core punching sheets in a stator core are mutually compressed in real time.

In one aspect, the present embodiment provides a stator structure of a generator set, including: a stator core; a fastening assembly for maintaining the stator core in a compressed state; and the force measuring assembly comprises a pressure sensor, and the pressure sensor is arranged between the stator core and the fastening assembly and is used for measuring the relative pressure value between the stator core and the fastening assembly.

In some of these embodiments, the fastening assembly comprises: the penetrating screw rod penetrates through the stator core; the fixing pieces are respectively arranged at the head and the tail of the through screw, are connected with the through screw in a relatively moving way, are in contact with the surface of the outer side of the stator core and are used for adjusting the degree of pressing the stator core; the pressure sensor is arranged between the fixing piece and the stator core.

In some embodiments, the fixing member includes a pressing plate and a nut sequentially arranged, the pressing plate is sleeved outside the through screw, the nut is in threaded connection with the through screw, and the force measuring assembly is arranged between the stator core and the nut.

In some of these embodiments, the nut is a pressure sensing nut.

In some embodiments, a spring element is arranged between the pressing plate and the nut, and the spring element is sleeved outside the penetrating screw rod.

In some embodiments, the fixing member further includes an insulating washer, the insulating washer is sleeved outside the through screw and disposed between the nut and the stator core, and the force measuring assembly is disposed outside the insulating washer relative to the stator core.

In some embodiments, the fixing member located at any side of the through-screw further includes at least a sleeve and a metal washer, and both the sleeve and the metal washer are sleeved outside the through-screw and both disposed between the nut and the stator core.

In some of these embodiments, the sleeve and the through-screw are arranged with a clearance.

In some of these embodiments, the pressure sensor is a fiber optic pressure sensor.

In some embodiments, the stator structure of the generator set comprises at least two through screws, and the force measuring assembly is arranged between a part of the through screws and the fastening assembly of the through screws.

On the other hand, the embodiment also provides a stator measuring point arrangement method, which is applied to the stator structure of the generator set in any one of the embodiments, and the method comprises the following steps: selecting an initial position screw; determining a penetrating screw which has no correlation with the initial screw and is closest to the initial screw; and taking the distance between the feed-through screw and the initial screw as the maximum distribution point interval.

In some embodiments, determining the closest penetrating screw to the initial screw without correlation comprises: establishing a feed-through screw distribution model based on the resolution of the generator set and the pressure sensor; loading the pre-tightening force of all the penetrating screws to a preset value; changing the pretightening force of the initial position screw rod, and determining the corresponding pressure value change amount of other penetrating screw rods; and determining the through screw corresponding to the maximum value in the pressure value change quantity smaller than the resolution of the pressure sensor as the through screw which has no correlation with the initial position screw and is closest to the initial position screw.

In some of these embodiments, the determination of the measurement resolution of the pressure sensor comprises: determining the required measuring range of the pressure sensor according to the design load of the through screw, and selecting the type of the pressure sensor; the measurement resolution of the pressure sensor is obtained.

In some embodiments, determining the closest penetrating screw to the initial screw without correlation comprises: loading the pre-tightening force of all the penetrating screws to a preset value; changing the pretightening force of the initial position screw rod, taking a penetrating screw rod to be determined whether to have correlation as a target screw rod, and measuring the pressure value change quantity at the target screw rod; taking the ratio of the change amount of the pressure value at the target screw to the change amount of the pretightening force of the initial screw as an actual influence factor; if the actual influence factor is larger than or equal to the preset influence factor threshold, judging that the target screw is related to the initial position screw; if the actual influence factor is smaller than the preset influence factor threshold value, judging that the target screw has no correlation with the initial position screw; and determining a target screw which has no correlation with the initial screw and is closest to the initial screw and is away from LM 0.

In some embodiments, the method further comprises determining whether the cross-threaded screw has a correlation with the initial position screw, and further comprising: establishing a feed-through screw distribution model based on the resolution of the generator set and the pressure sensor; loading the pretightening force of all the penetrating screws to a preset value; changing the pretightening force of the initial position screw rod, and determining the corresponding pressure value change amount of other penetrating screw rods; determining the through screw corresponding to the maximum value and the distance LM1 between the through screw and the initial screw in the pressure value change amount smaller than the resolution of the pressure sensor; the minimum value among LM0 and LM1 is determined as the maximum stationing interval.

In some embodiments, determining the closest penetrating screw to the initial screw without correlation comprises: loading the pre-tightening force of all the penetrating screws to a preset value; changing the pretightening force of the initial position screw rod, and measuring the pressure value change quantity of other penetrating screw rods; in the through-screw having a measured value of the change amount of the pressure value of 0, the through-screw closest to the home screw is determined as the through-screw closest to the home screw without correlation.

In some embodiments, the initial screw preload change comprises at least two change levels, and the correlation judgment of the target screw is respectively obtained according to different adjustment levels.

In some embodiments, the preload state of all the penetrating screws is 100% preload, and the initial screw preload is changed by adjusting to different loosening levels, wherein the loosening levels comprise: first grade, the through screw pretension load [ 85%, 100% ]; second grade, the through screw pretension load [ 70%, 85%); third grade, the through screw pre-tightened load [ 60%, 70%); fourth grade, piercing screw preload [ 10%, 60% of load); fifth grade, the feed-through screw preloads [0, 10% of the load).

Has the advantages that:

(1) the generator set stator structure provided by the embodiment can detect the stator core compression state in real time, and does not need to arrange a corresponding detection assembly on the iron core punching sheet, so that the influence on the stator core is avoided; the detection device is positioned at the outer side of the stator core, so that the interference of the stator core is less, and the measurement resolution is high;

(2) the stator structure of the generator set provided by the embodiment adopts an assembly part nesting mode, and the integrity is high;

(3) according to the stator measuring point arrangement method provided by the embodiment, on the premise of high accuracy, the number of measuring points is minimized, a high-accuracy and high-economical generator stator core penetrating screw measuring point arrangement scheme is obtained, powerful support is provided for overall compression state evaluation and fault early warning of a hydraulic generator core, scientific basis is provided for safe and reliable operation of a hydraulic generator, and reliable reference is provided for state maintenance and optimized operation of a unit.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a structural schematic diagram of a stator structure of a genset in accordance with some embodiments of the present application;

FIG. 2 is another structural schematic diagram of a stator structure of a genset in accordance with some embodiments of the present application;

FIG. 3 is a schematic structural view of a force measurement assembly provided by some embodiments of the present application;

reference numerals:

1. a stator core; 10. a feed-through screw; 201. a nut; 202. a spring member; 203. an insulating washer; 204. a sleeve; 205. a metal washer; 30. a force measuring assembly.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be considered as limiting the present application. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

"A and/or B" includes the following three combinations: a alone, B alone, and a combination of A and B.

The use of "adapted to" or "configured to" in this application means open and inclusive language that does not exclude devices adapted to or configured to perform additional tasks or steps. Additionally, the use of "based on" means open and inclusive, as a process, step, calculation, or other action that is "based on" one or more stated conditions or values may in practice be based on additional conditions or values beyond those stated.

In this application, the word "exemplary" is used to mean "serving as an example, instance, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is presented to enable any person skilled in the art to make and use the application. In the following description, details are set forth for the purpose of explanation. It will be apparent to one of ordinary skill in the art that the present application may be practiced without these specific details. In other instances, well-known structures and processes are not set forth in detail in order to avoid obscuring the description of the present application with unnecessary detail. Thus, the present application is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

On one hand, as shown in fig. 1 to 3, the present embodiment provides a stator structure of a generator set, which includes a stator core 1, a fastening assembly and a force measuring assembly 30; the fastening assembly is used for keeping the stator core 1 in a compression state; the force measuring assembly 30 comprises a pressure sensor arranged between the fastening assembly and the stator core 1 for measuring a relative pressure value between the fastening assembly and the stator core 1.

In the above embodiment, during the operation of the generator set, the compression state of the stator core 1 is affected by various factors, and the vibration generated by the thermal aging of the paint film of the core lamination and the hydraulic, mechanical and electromagnetic reasons is also an important reason for the deterioration of the compression state of the stator core 1. The long-term vibration in the radial direction, the axial direction and the tangential direction gradually deteriorates the compression state of the stator core 1. If the detection is not timely, operation accidents will occur, and serious economic loss is caused. In the embodiment, the force measuring assembly 30 is arranged between the fastening assembly and the stator core 1, and the pressure sensor of the force measuring assembly 30 is used for acquiring the relative pressure value between the stator core 1 and the fastening assembly in the running process of the generator set. Under the condition that the stator core 1 is loosened, the pressure between the stator core 1 and the fastening assembly is reduced, and the pressure sensor arranged between the stator core 1 and the fastening assembly can detect that the pressure is abnormally reduced (namely the detected pressure is smaller than a preset pressure value), so that the stator core 1 can be judged to be loosened.

In the above embodiment, the force measuring assembly 30 is arranged at the outer side of the stator core 1, and the force measuring assembly 30 is not required to be arranged between the core laminations of the stator core 1, so that electromagnetic interference can be prevented, and the stator core 1 itself is not required to be modified.

In some embodiments, the fastening assembly includes a penetrating screw 10 disposed through the stator core 1, fixing members are disposed at two ends of the penetrating screw 10, the fixing members are movably connected with the penetrating screw 10, the fixing members are in surface contact with an outer side of the stator core 1, the fixing members are adjusted by moving relative to the penetrating screw 10 to adjust a degree of compression on the stator core 1, and the pressure sensor is disposed between the fixing members and the stator core 1 to detect an axial stress of the penetrating screw 10 through the fixing members, so as to obtain a loosening condition of the stator core 1.

In the above embodiment, the stator core 1 is pretensioned by the fixing member. In the embodiment, the fixing parts are arranged on two sides of the stator core 1 to adjust the compression degree of the stator core 1, so that the pre-tightening setting of the generator set before operation is realized; and then a force measuring assembly 30 is arranged between the fixed piece and the stator core 1, so that the loosening condition of the stator core 1 is obtained.

The above embodiment can adapt to the length-diameter ratio of the feed-through screw 10, does not change the structure of the feed-through screw 10, realizes the high-precision online monitoring of the axial stress of the feed-through screw 10, and eliminates the monitoring blind area of the important component. After the generator set runs for a long time and the force measuring assembly 30 breaks down, only the force measuring assembly 30 needs to be replaced on two sides of the penetrating screw 10, the stator core 1 does not need to be operated, and the maintenance is convenient and low in maintenance cost. Through the force measuring assembly 30 arranged between the fixing piece and the stator core 1, the change value of the relative pressure value between the fixing piece and the stator core 1 is obtained, and further the operation condition of the generator set is obtained.

In some embodiments, the fixing member includes a pressing plate and a nut 201 sequentially disposed along the stator core 1, and the through-screw 10 is provided with an external thread matching with the nut 201, so as to achieve a threaded connection between the nut 201 and the through-screw 10, and further drive the pressing plate, thereby achieving a pre-tightening force setting of the stator core 1. On the other hand, through setting up the clamp plate that contacts with stator core 1, can effectively increase the area of contact of mounting and stator core 1, improve the stability of being connected of mounting and stator core 1, can effectively reduce simultaneously because of the mounting with the too narrow, the mounting compresses tightly stator core 1 for a long time of stator core 1 of the area of being stressed of stator core 1, lead to increasing the damage degree of stator core 1. The force measuring assembly 30 is arranged between the stator core 1 and the nut 201, can be selectively arranged between the nut 201 and the pressing plate, and can also be arranged between the pressing plate and the stator core 1, and the detection of the relative pressure value between the fixing piece and the stator core 1 can be realized.

In some embodiments, the nut 201 can adopt a pressure sensor nut 201, and the pressure sensor and the nut 201 are arranged integrally, so that parts needing to be installed are reduced, and the installation of the whole equipment is facilitated; meanwhile, in the installation process, when the nut 201 is used for pre-tightening the stator core 1, the pre-tightening force given to the stator core 1 by the nut 201 can be monitored in real time; set up like this, can be according to generating set's user demand, accurate adjusting nut 201 is to stator core 1's pretightning force.

In some embodiments, a spring member 202 is arranged between the pressing plate and the nut 201, the spring member 202 is sleeved outside the through screw 10, the spring member 202 is arranged to provide a pre-tightening force for the generator set stator structure in the operation process, when the stator core 1 becomes loose, the spring member 202 provides a self-adaptive adjustment force, and the compression deformation of the spring member 202 is used for compressing the stator core 1 again, so that the influence of the loosening of the stator core 1 on the generator set stator structure is avoided. The pre-tightening force is adjusted in the early stage, and the spring element 202 can be pre-compressed by a certain amount through adjustment of the nut 201, so that the pre-tightening force of the spring element 202 is provided. In the later maintenance process, under the condition that the spring part 202 still has a certain service life, the pretightening force of the spring part 202 can be adjusted again through the nut 201. The spring element 202 and the force measuring assembly 30 do not affect each other in function, and the positions of the spring element and the force measuring assembly can be adjusted at will under the condition that the spring element and the force measuring assembly perform functions. The spring member 202 may be a disc spring.

In some embodiments, the fixing member further includes an insulating washer 203, the insulating washer 203 is sleeved on the outer side of the through screw 10, the insulating washer 203 is disposed between the nut 201 and the stator core 1, and the force measuring assembly 30 is disposed on the outer side of the insulating washer 203 opposite to the stator core 1. The provision of the insulating washer 203 enables the components located outside the insulating washer 203 to be unaffected, effectively providing the measurement resolution of the force measuring assembly 30. On the other hand, the part of the piercing bolt 10 that is in contact with the fixture without providing the insulating washer 203 may be in contact with the fixture and the piercing bolt 10 by friction, which may damage the joint layer of the outer layer of the piercing bolt 10 and cause a short circuit. The insulating washer 203 is arranged, so that the situation that the penetrating screw 10 positioned outside the stator core 1 is short-circuited can be effectively avoided, and the use stability of the equipment is improved.

In some embodiments, the fixing member on any side of the through-screw 10 further includes at least a sleeve 204, the sleeve 204 is sleeved outside the through-screw 10, and the sleeve 204 can limit the through-screw 10, so as to reduce relative movement of the through-screw 10, further reduce the contact between the through-screw 10 and the stator core 1, and reduce the probability of relative friction between the through-screw 10 and the stator core 1. The fixing part on any side of the feed-through screw 10 at least comprises a metal gasket 205, the metal gasket 205 is sleeved outside the feed-through screw 10, and the metal gasket 205 has the advantage of good use stability, which is beneficial to providing the use stability of the whole equipment.

The sleeve 204 and the penetrating screw 10 are arranged in a clearance mode, the clearance between the sleeve 204 and the penetrating screw 10 is smaller than the clearance between the penetrating screw 10 and the stator core 1, the sleeve 204 is limited for the penetrating screw 10, the contact frequency with the stator core 1 is reduced, and meanwhile the sleeve 204 and the penetrating screw 10 are convenient to mount.

In some of these embodiments, the pressure sensor is a fiber optic pressure sensor. The environment has complex electromagnetic environment and large electromagnetic interference, and the monitoring precision of the electric sensor cannot meet the requirement; in this embodiment, the optical fiber pressure sensor has the advantage of being less affected by electromagnetism, which can effectively solve the problem and further improve the anti-interference capability of the force measuring assembly 30.

In some embodiments, the stator structure of the generator set includes at least two through screws 10, a force measuring assembly 30 is disposed between some of the through screws 10 and their fastening assemblies, and adjacent or similar through screws 10 have correlation, and when one or some of them become loose, the adjacent or similar through screws 10 where the force measuring assembly 30 is disposed can be detected, so that the force measuring assembly 30 does not need to be disposed at all the through screws 10. In the embodiment, at least part of the penetrating screw 10 is applied to a stator core 1 compression state detection device, so as to form a measuring point on the surface of the stator core 1, and the detection of the overall compression state of the stator core 1 is realized through a plurality of measuring points which are distributed.

On the other hand, the embodiment also provides a stator core 1 measuring point arrangement method, which is applied to the stator structure of the generator set in any one of the above embodiments, and comprises the following steps: selecting an initial position screw, determining a penetrating screw 10 which has no correlation with the initial position screw and is closest to the initial position screw, and taking the distance between the penetrating screw 10 and the initial position screw as the maximum distribution point interval. And based on the maximum point arrangement interval, the method is used for guiding the arrangement of the measuring points on the corresponding stator core 1 in the generator set.

The embodiment can detect the loosening state of each position of the stator core 1 of the generator set stator structure under the condition that few measuring points are arranged as far as possible, the detection performance is guaranteed, meanwhile, the cost can be effectively reduced, and the economical efficiency is improved.

In some embodiments, a distribution model of the through screws 10 is established based on the resolutions of the generator set and the pressure sensors, the simulation measuring points are based on the through screws 10 distributed on the stator core 1, and the measurement resolution of one pressure sensor is preset. Firstly, loading the pretightening force of all measuring points to a preset value; changing the pretightening force of the initial position screw in the simulated measuring point to obtain the corresponding pressure value change amounts of all other penetrating screws 10, wherein the display values of other penetrating screws 10 comprise displayable values and non-displayable values (or the display values are 0), and the positions of the non-displayable penetrating screws 10 are not considered; comparing the pressure value change quantity of all the penetrating screws 10 which can be displayed with the measurement resolution of the preset pressure sensor to obtain a plurality of measurement points which are smaller than the measurement resolution of the preset pressure sensor, selecting the penetrating screw 10 with the largest pressure value change quantity in the positions, and taking the distance between the penetrating screw 10 and the initial position screw as the maximum point distribution interval, wherein the maximum point distribution interval is LM 1.

In the embodiment, the arrangement process of the measuring points is placed in the model through computer modeling to obtain the maximum point arrangement interval, and the through screw 10 does not need to be measured manually in sequence.

The preset pretightening force is 100% pretightening force for completely pretightening the stator core 1, and in the measuring point arrangement method, the suspended pretightening force can be 100% pretightening force or other pretightening force smaller than 100%.

In other embodiments, determining the closest penetrating screw 10 that has no correlation with the initial position screw comprises: firstly, the pretightening force of all the penetrating screws 10 is loaded to a preset value, the pretightening force of the initial screw is changed, and the pressure value change quantity at the target screw is measured. Taking the ratio of the change amount of the pressure value at the target screw to the change amount of the initial screw as an actual influence factor; presetting an influence factor threshold, acquiring an actual influence factor of the initial screw rod on the target screw rod by the method, comparing the actual influence factor with the preset influence factor threshold, and if the influence factor of the initial screw rod on the target screw rod is greater than or equal to the preset influence factor threshold, judging that the target screw rod is related to the initial screw rod; if the influence factor of the initial position screw rod on the target screw rod is smaller than the preset influence factor threshold value, the target screw rod is judged to be irrelevant to the initial position screw rod, and based on the method, a maximum distribution interval LM0 can be obtained.

The embodiment can realize direct reconstruction of the existing generator set, the plurality of measuring points are arranged on the stator core 1, powerful support can be provided for overall compression state assessment and fault early warning of the stator core 1 of the hydraulic turbine generator, scientific basis is provided for safe and reliable operation of the hydraulic turbine generator, and reliable reference is provided for state maintenance and optimized operation of the generator set.

In some of the embodiments, the two embodiments are used together, and compared, a relatively small value is selected from LM0 and LM1 as the maximum stationing interval to guide the setting of the measuring points. The minimum value is selected, so that the detection performance of the compression state of the stator core 1 of the stator structure of the generator set can be ensured greatly.

In other embodiments, a method of determining the closest penetrating screw 10 to the home screw without correlation thereto comprises the steps of: acquiring the measurement resolution of the pressure sensor; loading the pretightening force of all the penetrating screws 10 to a preset value, taking any penetrating screw 10 of the stator structure of the generator set as an initial position screw, and taking any other penetrating screw 10 which needs to determine whether the penetrating screw has correlation as a target screw; changing the pretightening force of the initial position screw, measuring the pressure value change quantity at the target screw, and comparing the pressure value change quantity of the target screw with the measurement resolution of the pressure sensor; if the pressure value change quantity of the target screw is larger than or equal to the measurement resolution of the pressure sensor, judging that the target screw has correlation with the initial position screw; if the pressure value change amount of the target screw is smaller than the measurement resolution of the pressure sensor, it is determined that the target screw does not have correlation with the initial position, and based on the above method, a maximum point distribution interval LM1 can be obtained.

The method for determining the measurement resolution of the pressure sensor comprises the following steps: determining the load of the used feed-through screw 10, and selecting a pressure sensor with a proper measuring range for the force measuring assembly 30 according to the load stress of the feed-through screw 10; and obtaining the measurement resolution of the pressure sensor through experiments according to the type-selected pressure sensor.

Wherein, the load of the penetrating screw 10 is related to one or more of parameters of the pressure between the iron core sheets, the effective compression area of the iron core, the number of screws and the diameter of the screws. The selection of the pressure sensor is based on the fact that the measuring range of the pressure sensor is larger than the load of the through screw 10, the measuring range of the pressure sensor cannot be too large, if the measuring range of the pressure sensor is too large, the minimum pressure change value which can be accurately measured by the pressure sensor can be reduced, and the measuring accuracy is further reduced. In some examples, the range of the pressure sensor can be selected to be 1.2-2 times the feed-through screw 10.

In some embodiments, the method for acquiring the influence factor of the initial position screw on the target screw comprises the following steps: under the condition that the generator set does not work, one penetrating screw 10 is selected as an initial position screw on a stator core 1, the pretightening force of the initial position screw is increased or reduced, the other penetrating screw 10 is selected as a target screw, the change quantity of the pressure value of the target screw is measured, the change quantity of the pressure value of the target screw is compared with the pretightening force change quantity of the initial position screw, and the obtained value is used as an actual influence factor. If the influence factor is 0, the state of the initial screw does not influence the target screw; if the influence factor is 1, the state of the initial screw is closely related to the target screw. And presetting an influence factor threshold according to requirements, and if the influence factor of the target screw is smaller than the preset influence factor threshold, setting a measuring point at the target screw.

Wherein, the threshold value of the influence factor is determined according to the power, the service condition and the operation and maintenance requirements of the generator set, and cannot be too high or too low. Too high a distance between adjacent measuring points can make the distance too close, which can increase the cost of retrofitting or manufacturing the generator set, and can be prohibitive for low power generator sets. And too low can make adjacent measurement station distance too far, and the detection effect is sensitive inadequately, can not well obtain the operating mode of unit.

In some embodiments, the initial screw preload change comprises at least two change levels, and the correlation determination of the target screw is respectively obtained according to different adjustment levels.

In the above embodiment, the maximum point distribution interval obtained by the final measurement is different in the difference of the pretightening force variation of the initial screw, because the pretightening force variation of the initial screw is small, the influence of the initial screw on other penetrating screws 10 is also small, and the maximum point distribution interval obtained by the final measurement is also small. Under the condition, the maximum point distribution intervals of different levels are obtained corresponding to different adjusting levels of pretightening force change, and finally, the loosening conditions of other penetrating screws 10 can be accurately obtained according to the pressure value change quantity of the penetrating screws 10 at the arrangement measuring points.

The pretightening states of all the penetrating screws 10 are 100% pretightening, the pretightening force of the initial screw is changed by adjusting to different loosening grades, and the loosening grades comprise: first grade, the through screw 10 pretension load [ 85%, 100% ]; second grade, the feed-through screw 10 pre-load [ 70%, 85%); third grade, the feed-through screw 10 pre-tensioned [ 60%, 70%) of the load; fourth grade, the feed-through screw 10 pre-tensioned [ 10%, 60%) of load; in the fifth stage, the feed-through screw 10 is preloaded to 0, 10% of the load.

Through the embodiment, different loosening grades are set, a certain range is given, a range threshold value can be provided firstly, for example, a first loosening grade is set, and when the preset pretightening force of the penetrating screw 10 is 85% of the pretightening load, other preset pretightening force larger than 85% can be measured; and different loosening conditions are corresponding to corresponding working conditions in actual production and use, so that guidance basis is provided for production and use.

In some of these embodiments, the method of the closest penetrating screw 10 having no correlation with the home screw comprises the steps of: taking a penetrating screw 10 to be determined whether the screw has correlation as a target screw; if the target screw is related to the initial screw, continuously selecting a penetrating screw 10 which is farther away from the initial screw relative to the target screw as a target screw, and judging the relevance again; if the target screw is not related to the initial position screw, continuously selecting a penetrating screw 10 which is closer to the initial position screw relative to the target screw as the target screw, and judging the relevance again; and repeating the steps according to whether the target screw has correlation or not until the penetrating screw 10 which has no correlation with the initial position screw and is closest to the initial position screw is obtained.

In the process of actually obtaining the target screw, firstly, selecting a relatively far screw as the target screw (namely, directly measuring the adjacent through screw 10 closest to the initial screw), and when the actual influence factor of the initial screw on the relatively far target screw does not reach the preset influence factor threshold value, then, measuring the relatively near screw is not needed; if the actual influence factor of the initial position screw rod on the relatively far target screw rod exceeds the threshold value of the set influence factor obtained by measurement, the relatively near screw rod needs to be measured again so as to avoid omission of measuring points and incomplete measurement of the stator structure of the generator set.

In the embodiment, after the types of the penetrating screw 10 and the force measuring assembly 30 are selected, the arrangement mode of adjacent measuring points is obtained, production and manufacturing can be guided, the optimal distribution interval of the axial stress measuring points of the generator penetrating screw 10 is determined, the number of the measuring points is minimized on the premise of ensuring high accuracy, and the arrangement scheme of the measuring points of the generator stator core 1 penetrating screw 10 with high accuracy and high economy is obtained.

In some embodiments, the initial position screw pre-tightening force is changed by adjusting to different loosening levels, wherein the loosening levels comprise: first grade, [ 85%, 100% of the feed-through screw 10 load ]; second grade, [ 70%, 85% of the feed-through screw 10 load; third grade, [ 60%, 70% of the feed-through screw 10 load; fourth grade, [ 10%, 60% of the feed-through screw 10 load); fifth grade, [0, 10% of the feed-through screw 10 load. According to different loosening grades, the pre-tightening force of the initial position screw rod is selectively adjusted, so that the debugging efficiency of the pre-tightening force is guaranteed.

The pressure sensor can be in signal connection with the alarm, different alarm levels are correspondingly set according to the loosening levels, and when the initial position screw pre-tightening force is adjusted to a corresponding level, the alarm can send out a corresponding alarm signal to remind an operator whether the pre-tightening force reaches a corresponding adjustment degree.

The embodiment further provides a unit looseness early warning method, under the specified working condition, the change amount of an actual stress value measured by the penetrating screw 10 relative to a preset stress value is compared with the preset stress value, and a ratio section is selected as an early warning level, for example, if the ratio of the actual stress value relative to the preset stress value and the preset stress value is 85% -100%, the result is judged to be good; when the ratio is 70-85%, judging that attention is needed; when the ratio is between 60 and 70 percent, determining that the loosening is preliminary; when the ratio is 10-60%, determining that the loosening is serious; and when the ratio is 0-10%, judging the fracture is suspected. Of course, the above is only an example, and the ratio range and the early warning level thereof can be reasonably changed according to different operation and maintenance requirements of the unit so as to meet actual needs.

With the adoption of the stator core 1 measuring point arrangement method provided by the embodiment, after the influence factor value between the adjacent measuring points is obtained, the influence factor value between the penetrating screws 10 of the adjacent measuring points can be obtained (according to the distance from the initial position screw, the pressure value change quantity of the penetrating screws 10 of the adjacent measuring points and the initial position screw has a certain linear relationship), and when the pressure value change trend of the penetrating screws 10 of the adjacent measuring points is abnormal, the phenomenon that the penetrating screws 10 near the measuring points are loosened abnormally can be judged in an auxiliary manner.

In the embodiment, the measuring points are arranged, so that the loosening condition of the penetrating screw 10 at the positions other than the measuring points can be further detected, and more comprehensive monitoring performance is realized.

The stator structure and the stator measuring point arrangement method of the generator set provided by the embodiment of the application are described in detail, specific examples are applied in the description to explain the principle and the implementation mode of the application, and the description of the embodiment is only used for helping to understand the method and the core idea of the application; meanwhile, for those skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims (10)

1. A generator set stator structure, comprising:

a stator core;

a fastening assembly for maintaining the stator core in a compressed state;

and the force measuring assembly comprises a pressure sensor, and the pressure sensor is arranged between the stator core and the fastening assembly and is used for measuring the relative pressure value between the stator core and the fastening assembly.

2. The genset stator structure of claim 1, wherein the fastening assembly comprises:

the penetrating screw rod penetrates through the stator core;

the fixing pieces are respectively arranged at the head and the tail of the through screw rod, are connected with the through screw rod in a relatively moving way, are in contact with the surface of the outer side of the stator core and are used for adjusting the degree of pressing the stator core;

the pressure sensor is arranged between the fixed piece and the stator core.

3. The generator set stator structure of claim 2, wherein the fixing member comprises a pressing plate and a nut which are sequentially arranged, the pressing plate is sleeved outside the through screw, the nut is in threaded connection with the through screw, and the force measuring assembly is arranged between the stator core and the nut.

4. The genset stator structure of claim 3 wherein the nut is a pressure sensing nut.

5. The generator set stator structure of claim 3, wherein a spring member is disposed between the pressure plate and the nut, and the spring member is disposed outside the through screw.

6. The generator set stator structure of claim 3, wherein the fixture further comprises an insulating plate, the insulating plate is sleeved outside the through screw and disposed between the nut and the stator core, and the force measuring assembly is disposed outside the insulating plate relative to the stator core.

7. The generator set stator structure of claim 3, wherein the fixing member located on any side of the through-screw further comprises at least a sleeve and a metal pressing plate, and the sleeve and the metal pressing plate are both sleeved outside the through-screw and both disposed between the nut and the stator core.

8. The genset stator structure of claim 7, wherein the sleeve and the feed-through screw are disposed in a clearance arrangement.

9. The genset stator structure of claim 1 wherein the pressure sensor is a fiber optic pressure sensor.

10. The stator structure of a generator set according to claim 2, comprising at least two of said feed-through screws, wherein said force-measuring assembly is disposed between a portion of said feed-through screws and a fastening assembly of said feed-through screws.

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