CN111551853B - Hydro-generator stator core lamination loosening fault detection method - Google Patents
Hydro-generator stator core lamination loosening fault detection method Download PDFInfo
- Publication number
- CN111551853B CN111551853B CN202010480810.7A CN202010480810A CN111551853B CN 111551853 B CN111551853 B CN 111551853B CN 202010480810 A CN202010480810 A CN 202010480810A CN 111551853 B CN111551853 B CN 111551853B
- Authority
- CN
- China
- Prior art keywords
- stator core
- value
- generator
- frequency vibration
- vibration amplitude
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/34—Testing dynamo-electric machines
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K1/00—Details of thermometers not specially adapted for particular types of thermometer
- G01K1/02—Means for indicating or recording specially adapted for thermometers
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K1/00—Details of the magnetic circuit
- H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
- H02K1/12—Stationary parts of the magnetic circuit
Abstract
The invention provides a method for detecting the loosening fault of a stator core lamination of a hydraulic generator, which comprises the following steps: setting a normal temperature value, a highest temperature alarm value, a normal vertical polar frequency vibration amplitude value and an alarm value of a stator core of the generator set; acquiring a temperature value of a stator core of a generator set, active power of a generator, exciting current of the generator and a vertical polar frequency vibration amplitude value of the stator core; establishing a mathematical model to obtain a maximum temperature value, a synthetic value and an average value of the vertical polar frequency vibration amplitude; calculating the maximum temperature of the stator core, the vertical pole frequency vibration slow variable and the primary and secondary alarm predicted values, determining the loosening direction of the stator core lamination, finally detecting the loosening fault of the stator core lamination, making maintenance and treatment plans and measures, and treating the stator core lamination of the generator. Accurate detection of the loosening fault of the stator core lamination of the hydraulic generator is achieved.
Description
Technical Field
The invention relates to a detection method, in particular to a method for detecting a loosening fault of a lamination of a stator core of a generator, and belongs to the technical field of generator fault detection.
Background
The loosening of the lamination sheets of the stator core is one of the important reasons causing the fault of the generator, and the main reasons causing the loosening of the lamination sheets of the stator of the generator are as follows: 1) defects existing in structural design, lamination material, manufacturing and the like of the generator; 2) the installation requirements are not met due to insufficient tension force or compression density in the stator core lamination installation process; 3) the lamination of the stator core of the generator is polluted due to oil leakage of the oil basin of the guide bearing. When the lamination of the stator core of the generator is loosened, hysteresis loss of the stator core is increased, local temperature is increased and vibration of the core is increased, and the insulation damage and the deformation of the stator core or the winding bar are aggravated under the environment of long-term high temperature, high heat and vibration of the stator core or the winding bar of the generator, so that the loosening condition of the lamination of the stator of the generator is detected in real time, and the safe and stable operation of the generator is very necessary.
The detection of the prior art to the loosening fault of the lamination of the stator core of the generator has the following steps: 1) the looseness of the stator core lamination is analyzed through the tightness of a tension screw of the generator stator core, the work needs to be carried out after a machine set is stopped when the machine set is overhauled or the looseness of the stator core lamination is suspected, and the real-time performance is insufficient; 2) the method is characterized in that the looseness of the lamination of the stator core is analyzed through noise detection in the running state of the generator, and the method is easily influenced by the running working condition of the generator and restricted by the technical level of detection personnel; 3) the method comprises the following steps that the temperature of a stator core of a generator is detected and analyzed, the lamination looseness of the stator core is detected, temperature change cannot be found timely due to more temperature detection points, and meanwhile, the factors causing the temperature change of the core are more, and manual analysis and removal are needed; 4) the method comprises the following steps of detecting and analyzing the looseness of stator core laminations through vibration data of a generator stator core, wherein due to the fact that a plurality of influence factors of core vibration are caused, manual analysis and elimination are needed; 5) when in maintenance, the iron loss test or the magnetization test is carried out on the stator core, the lamination looseness of the stator core is analyzed, the working procedure is complex, the manpower investment is large, and the required time is long. Therefore, there is a need for improvements in the prior art.
Disclosure of Invention
According to the reason of stator lamination looseness, aiming at the defects of the existing detection and analysis method for the stator core lamination looseness of the generator, in order to avoid the situations that the insulation damage fault of the generator stator is caused and the service life of the generator is reduced because the lamination looseness of the generator stator core cannot be found in time, the invention provides a method for detecting the lamination looseness fault of the stator core of the hydraulic generator on the basis of the maximum temperature of the stator core and the change mechanism of the vertical polar frequency vibration synthetic value of the stator core, and the mallat wavelet algorithm and the PCA data main component analysis method.
The invention is realized by the following technical scheme: a hydro-generator stator core lamination loosening fault detection method is characterized by comprising the following steps:
(15) setting normal temperature value T of each part of stator core of hydroelectric generating set z Alarm value T of maximum temperature of stator core a Normal vertical pole frequency vibration amplitude A of each part of stator core z Stator core vertical pole frequency vibration alarm value A a ；
(16) Obtaining the iron core temperature value T of each part of the stator of the generator set by the existing temperature sensor, active power transmitter, current transmitter and vibration sensor of the water-turbine generator set and the connected computer and state detection system i The active power of the generator, the exciting current of the generator and the vertical polar frequency vibration amplitude of each part of the stator core;
(17) according to the temperature value T of each part of the stator core obtained in the step (2) i Finding out the maximum temperature T of the stator core max ；
(18) Obtaining the vertical polar frequency vibration amplitude A of each part of the stator core according to the step (2) i Calculating the resultant A of the vibration amplitudes of the vertical polar frequencies of the stator core according to the following formula t ：
In the formula, A t A resultant value, A, representing the amplitude of the vertical pole frequency vibration of the stator core i Representing the vertical polar frequency vibration amplitude of the stator core at the corresponding position;
(19) the highest temperature value T of the stator core found in the step (3) max And (3) establishing a mathematical model with the generator active power and the generator exciting current obtained in the step (2), and obtaining the current highest temperature value T of the stator core by using a computer, the existing mallat wavelet algorithm and a PCA data principal component analysis method g ；
(20) Establishing a mathematical model according to the active power and exciting current of the generator obtained in the step (2) and the composite value of the vertical polar frequency vibration amplitude of the iron core obtained in the step (4), and obtaining the composite value A of the current vertical polar frequency vibration amplitude of the stator iron core by using a computer, the existing mallat wavelet algorithm and a PCA data principal component analysis method;
(21) According to the current maximum temperature value T of the stator core in the step (5) g The average value of the maximum temperature of the stator core in the past 180 days is calculated according to the following formula
In the formula, T gn The maximum temperature value of the stator core is the daily average of the last 180 days; (ii) a
(22) According to the composite value A of the current vertical polar frequency vibration amplitude of the stator core in the step (6), calculating the average value of the vertical polar frequency vibration amplitude of the stator core in the past 180 days according to the following formula
In the formula, A n The composite value of the daily average vertical polar frequency vibration amplitude of the past 180 days;
(23) according to the current maximum temperature value T of the stator core in the step (5) g And (7) average value of maximum temperature of stator core in past 180 days
Calculating the maximum temperature slow variable quantity delta T of the stator core according to the following formula:
(24) according to the composite value A of the current vertical polar frequency vibration amplitude of the stator core in the step (6) and the average value of the composite value A of the vertical polar frequency vibration amplitude of the stator core in the past 180 days in the step (8)
Calculating a stator core vertical pole frequency vibration slow variation quantity delta A:
(25) according to the current highest temperature value T of the stator core in the step (5) g And (9) calculating a first-level alarm predicted value T of the highest temperature of the stator core according to the slow variation quantity delta T p1 Second-level alarm predicted value T p2 ：
T p1 ＝T g +ΔT·D 1 ；
T p2 ＝T g +ΔT·D 2 ；
Wherein D 1 、D 2 For a set number of days of early warning, D 2 ＜D 1 ；
(26) According to the composite value A of the current vertical polar frequency vibration amplitude of the stator core in the step (6) and the slow variation delta A in the step (10), calculating a primary alarm predicted value A of the vertical polar frequency vibration of the stator core p1 Second-level alarm prediction value A p2 ：
A p1 ＝A+ΔA·D 1 ；
A p2 ＝A+ΔA·D 2 ；
Wherein D 1 、D 2 For a set number of days of early warning, D 2 ＜D 1 ；
(27) According to the primary alarm predicted value and the secondary alarm predicted value of the highest temperature of the stator core in the step (11) and the primary alarm predicted value and the secondary alarm predicted value of the vertical polar frequency vibration of the stator core in the step (12), performing Fourier transform on the vertical vibration amplitude of the stator core through a computer, and calculating the vertical polar frequency vibration phase of the stator core to determine the loosening direction of the lamination of the stator core;
fourier expanded signal function:
vibration phase position:
in the formula: a is 0 、a n 、b n Are Fourier coefficients;
(28) comparing the data from steps (2) - (13) with the set data from step (1) as follows:
the maximum temperature value T of the stator core in the step (5) g Stator core normal temperature value T > set z ；
The composite value A of the stator core vertical polar frequency vibration amplitude in the step (6) is larger than the set normal stator core vertical polar frequency vibration amplitude A z ；
Drawing a curve by taking the composite value of the maximum temperature value of the stator core and the vertical polar frequency vibration amplitude of the stator core as a vertical coordinate and time as a horizontal coordinate, and observing the data change trend;
The maximum temperature primary alarm prediction value T of the stator core in the step (11) p1 Set maximum temperature alarm value T of stator core a ；
The primary alarm prediction value A of the composite value of the vertical polar frequency vibration amplitude of the stator core in the step (12) p1 Stator core vertical polar frequency vibration alarm amplitude A greater than set a ；
Detecting a slight loosening fault of the stator core lamination, and checking and fastening the tension force or the compression density of the stator lamination of the generator by a maintainer by selecting a machine, and checking oil contamination conditions of a generator room and the surrounding environment;
the secondary alarm prediction value T of the maximum temperature of the stator core in the step (11) p2 Set maximum temperature alarm value T of stator core greater than set a ；
The secondary alarm prediction value A of the composite value of the vertical polar frequency vibration amplitude of the stator core obtained in the step (12) p2 Stator core vertical polar frequency vibration alarm amplitude A greater than set a ；
And detecting the serious loosening fault of the stator core lamination, making a maintenance and treatment plan and measure, and treating the generator stator core lamination.
The mathematical model of the step (5) is established by the following steps:
51) the highest temperature value T of the stator core of the generator set found in the step (3) max The active power P 'of the generator obtained in the step (2) is effective value within the range of 90-250MW, and the excitation current I' of the generator is effective value within the range of 1000-3600A;
52) The active power P of the generator is taken as an X coordinate, the exciting current I of the generator is taken as a Y coordinate, and the highest temperature T of the stator core max Establishing a three-dimensional graph for the Z coordinate; obtaining a cross point A of the generator exciting current I 'and the generator active power P' at the same moment on an X, Y plane of the three-dimensional graph; from the intersection A, a straight line parallel to the Z axis is formed until the maximum temperature T of the stator core is reached max The horizontal planes intersect to form a point B, and the maximum temperature value T of the stator core corresponding to the point B max That is, the highest temperature T of the stator core at the same time max ', the active power P ' of the generator and the exciting current I ' of the generator are determined by a three-dimensional relation modelA value of the metric;
53) using the three-dimensional relation model of the step 52) and the maximum temperature value T of the stator core max The highest temperature value T of the current stator core is obtained by the existing mallat wavelet algorithm and PCA data principal component analysis method as the source data of the mallat wavelet algorithm and the PCA data principal component analysis method g 。
The mathematical model of the step (6) is established by the following steps:
61) and (4) obtaining a resultant value A of the vertical polar frequency vibration amplitude of the stator core t An effective range of' is 0-50 um; the effective range of the active power P' of the generator is 90-250 MW; the effective range of the generator exciting current I' is 1000-3600A;
62) The active power P of the generator is taken as an X coordinate, the exciting current I of the generator is taken as a Y coordinate, and the resultant value A of the vertical polar frequency vibration amplitude of the stator core t Establishing a three-dimensional graph for the Z coordinate; acquiring a cross point A of a generator exciting current I 'and a generator active power P' at the same moment on an X, Y plane of a graph; from the intersection point A, making a straight line parallel to the Z axis to a resultant value A of the vibration amplitude of the stator core vertical polar frequency with the Z axis t The horizontal plane is intersected to form a point B, and the resultant value A of the vertical polar frequency vibration amplitude of the stator core corresponding to the point B t ' is the composite value A of the vertical polar frequency vibration amplitude of the stator core at the same time t ', the active power P ' of the generator and the exciting current I ' of the generator are determined by a three-dimensional relation model, and the synthetic value A of the vertical polar frequency vibration amplitude of the stator core t ’；
63) Using the three-dimensional relation model of the step 62) and the composite value A of the vertical polar frequency vibration amplitude of the stator core t The method is used as source data of a mallat wavelet algorithm and a principal component analysis method of PCA data, and a composite value A of the vibration amplitude of the vertical polar frequency of the current stator core is obtained through the existing mallat wavelet algorithm and the PCA data principal component analysis method.
The basic principle of the invention is that the judgment and the positioning of the stator core lamination loosening condition are realized by the variation trend of the maximum temperature value of the stator core and the vertical polar frequency vibration value of the stator core, and by the existing mallat wavelet algorithm, the PCA data principal component analysis method and the phase analysis of the vertical polar frequency vibration signal of the stator core, and the specific method is as follows: taking the maximum temperature value of the stator core and the vertical polar frequency vibration amplitude of the stator core as main observed quantities, if the two quantity values have the trend of increasing, and taking the current numerical value and the slow variable as calculation bases, if the two quantity values exceed the alarm value within 30 days, reporting a first-level alarm, and if the two quantity values exceed the alarm value within 10 days, reporting a second-level alarm; after the operation and maintenance personnel receive the alarm information, the computer analyzes the stator core vertical vibration polar frequency signal to determine the stator core vibration direction and inspect and process the generator stator core lamination.
The invention has the following advantages and effects: by adopting the scheme, the loosening condition of the stator core lamination can be detected and analyzed on line in real time, and the early warning of the loosening change condition can be realized by respectively carrying out primary warning and secondary warning on the highest temperature of the stator core and the vertical polar frequency vibration amplitude of the stator core. The problems that conventional inspection and data analysis means are insufficient in instantaneity, easily influenced by the operating condition of the generator and the technical level of detection personnel, more interference factors, more complex in elimination, higher in test development input cost and the like are solved, the sensing, analyzing and diagnosing capabilities of abnormal conditions of the loosening of the stator core lamination are finally improved, timely and effective measures are taken for operation and maintenance personnel, the accident enlargement is prevented, the economic loss is reduced, the powerful support is provided, and the operating life of the generator is prolonged.
Drawings
Fig. 1 and 2 are schematic diagrams of the layout of stator core temperature and vertical polar frequency vibration detection points;
FIG. 3 is a three-dimensional relationship model diagram of the maximum temperature of the stator core;
FIG. 4 is a three-dimensional relationship model diagram of the vertical pole frequency vibration amplitude of the stator core;
FIGS. 5 and 6 are frequency spectrum and phase diagrams of stator vertical pole frequency vibration with loose stator core laminations;
FIG. 7 is a graph of maximum temperature of the stator core and amplitude of vertical pole frequency vibration.
Detailed Description
The invention is further described below with reference to examples;
example 1
In the embodiment 1, the actual detection is performed by taking the operation condition of a No. 2 hydraulic generator set of a certain power plant as an example, the temperature of a stator core of the hydraulic generator is 34 temperature measurement detection points in total, and the circumference of the generator is divided into an upper layer, a middle layer and a lower layer of temperature measurement arrangement; the number of the stator core vertical polar frequency vibration sensors is 3, and the sensors are uniformly distributed around the upper end of the generator according to an included angle of 120 degrees, and are shown in attached figures 1 and 2;
the method for detecting the loosening fault of the stator core lamination of the hydraulic generator comprises the following steps:
(1) setting normal temperature value T of each part of stator core of hydroelectric generating set z 46 deg.C, alarm value T of maximum temperature of stator core a The normal vertical polar frequency vibration amplitude of each part of the stator core is A at 50 DEG C z 9.9um, alarm value A of stator core vertical polar frequency vibration a ＝30um；
(2) Through the existing temperature sensor, active power transmitter, current transmitter and vibration sensor of No. 2 generator set and the connected computer and state detection system, respectively obtain the stator core temperature data under the condition of 34 stator core lamination operation, and the stator core vertical polar frequency vibration amplitude, generator active power data and generator exciting current data collected by 3 stator core vertical polar frequency vibration sensors, see Table 1;
TABLE 1
(3) Finding out the highest temperature value from the 34 stator core temperature values obtained in the step (2):
T max ＝T 5 ＝46.3℃；
(4) obtaining from step (2)3 vertical polar frequency vibration amplitude A i Calculating the resultant A of the vibration amplitudes of the vertical polar frequencies of the 3 stator cores according to the following formula t ：
(5) Establishing a mathematical model according to the following steps by using the maximum temperature value 46.3 ℃ of the stator core found in the step (3) and the generator active power 125MW and the generator exciting current 1500A obtained in the step (2):
51) maximum temperature value T of stator core of generator set max ' is 46.3 ℃, has effective value in the range of 5-125 ℃, has the active power P ' of 125MW, is effective in the range of 90-250MW, has the excitation current I ' of 1500A, and is effective in the range of 1000-3600A, see Table 2;
TABLE 2
| Maximum temperature value T of stator core max ’(℃) | 46.3 |
| Generator active power P' (MW) | 125 |
| Generator exciting current I' (A) | 1500 |
52) The active power P of the generator is taken as an X coordinate, the exciting current I of the generator is taken as a Y coordinate, and the highest temperature T of the stator core is taken max Establishing a three-dimensional graph for the Z coordinate; obtaining a cross point A of the generator exciting current I 'and the generator active power P' at the same moment on an X, Y plane of the three-dimensional graph;from the intersection A, a straight line parallel to the Z axis is formed until the maximum temperature T of the stator core is reached max The horizontal planes intersect to form a point B, and the maximum temperature value T of the stator core corresponding to the point B max That is, the highest temperature T of the iron core at the same time max ', the active power P ' of the generator and the exciting current I ' of the generator are determined by a three-dimensional relation model to obtain the highest temperature value T of the stator core max ' -46.3 ℃, see fig. 3;
53) using the three-dimensional relation model of the step 52) and the maximum temperature value T of the stator core max The highest temperature value T of the current stator core is obtained by the existing mallat wavelet algorithm and PCA data principal component analysis method as the source data of the mallat wavelet algorithm and the PCA data principal component analysis method g See table 3, fig. 3;
TABLE 3
(6) Obtaining the active power 125MW and the exciting current 1500A of the generator obtained in the step (2), and the composite value A of the vertical polar frequency vibration amplitude of the stator core in the step (4) t The mathematical model is established according to the following steps:
61) resultant value A of vertical polar frequency vibration amplitude of generator stator core t ' is 10.0um, effective in the range of 0-50 um; the active power P' of the generator is 125MW and is effective in the range of 90-250 MW; generator excitation current I' 1500A is valid within the range of 1000-;
TABLE 4
62) Stator iron with generator active power P as X coordinate and generator exciting current I as Y coordinate Composite value A of core vertical polar frequency vibration amplitude t Establishing a three-dimensional graph for the Z coordinate; acquiring a cross point A of a generator exciting current I 'and a generator active power P' at the same moment on an X, Y plane of a graph; from the intersection point A, making a straight line parallel to the Z axis to a resultant value A of the vibration amplitude of the stator core vertical polar frequency with the Z axis t The horizontal plane is intersected to form a point B, and the resultant value A of the vertical polar frequency vibration amplitude of the stator core corresponding to the point B t ' is the composite value A of the vertical polar frequency vibration amplitude of the stator core at the same time t ', the active power P ' of the generator and the exciting current I ' of the generator are determined by a three-dimensional relation model, the synthetic value of the vertical polar frequency vibration amplitude of the stator core is 10.0um, and the figure is shown in figure 4;
63) using the three-dimensional relation model of the step 62) and the composite value A of the vertical polar frequency vibration amplitude of the stator core t The current composite value A of the vertical polar frequency vibration amplitude of the stator core is obtained by the existing mallat wavelet algorithm and PCA data principal component analysis method as the source data of the mallat wavelet algorithm and the PCA data principal component analysis method, and is shown in the table 5 and the figure 4;
TABLE 5
(7) According to the maximum temperature value T of the stator core in the step (5) g The average value of the maximum temperature of the stator core in the past 180 days is calculated according to the following formula 
In the formula, T gn The maximum temperature value of the stator core is the daily average of the last 180 days;
(8) according to the composite value A of the stator core vertical polar frequency vibration amplitude in the step (6), calculating the stator core vertical polar frequency vibration amplitude of the past 180 days according to the following formulaAverage value of values
In the formula, A n Averaging the daily average fixed iron core vertical polar frequency vibration amplitude composite value of the past 180 days;
(9) according to the current maximum temperature value T of the stator core in the step (5) g And (7) average value of maximum temperature of stator core in past 180 days
Calculating the maximum temperature slow variable quantity delta T of the stator core according to the following formula:
analogizing in turn, calculating the delta T 4 ………………ΔT 12 As shown in table 6:
TABLE 6
(10) According to the combined value A of the current vertical polar frequency vibration amplitude of the stator core in the step (6) and the average value of the combined values of the vertical polar frequency vibration amplitude of the stator core in the past 180 days in the step (8)
Calculating the vertical pole frequency vibration slow variable quantity delta A of the stator core according to the following formula:
analogizing in turn, calculating delta A 4 ……………ΔA 12 The values of (a) are shown in Table 7:
TABLE 7
(11) According to the current highest temperature value T of the stator core in the step (5) g And (9) calculating a first-level alarm predicted value T of the highest temperature of the stator core according to the slow variation quantity delta T p1 Second-level alarm predicted value T p2 ：
T p1 ＝T g +ΔT·D 1 ；
T p2 ＝T g +ΔT·D 2 ；
Wherein D 1 30 days, D 2 Day 10, as in table 8:
TABLE 8
First-level alarm (take column 1 data as an example):
T p1 ＝T g +ΔT·D 1 46.3+ 0.30X 30 ═ 55.3 ℃ > 50 ℃, and 30 days according to the current temperature value and the buffer variableInner T p1 The variation value of (2) exceeds the alarm value of 50 ℃;
secondary alarm (take column 4 data as an example):
T p2 ＝T g +ΔT·D 2 46.5+0.50 × 10 ═ 51.5 ℃ > 50 ℃, according to the current temperature value and the buffer value, T is within 10 days p2 The variation value of (2) exceeds the alarm value of 50 ℃;
(12) according to the combined value A of the current vertical polar frequency vibration amplitude of the stator core in the step (6) and the slowly-varying quantity delta A in the step (10), calculating a primary alarm predicted value A of the combined value of the vertical polar frequency vibration of the stator core p1 Second-level alarm prediction value A p2 ：
A p1 ＝A+ΔA·D 1 ；
A p2 ＝A+ΔA·D 2 ；
Wherein D 1 30 days, D 2 Day 10, as in table 9:
TABLE 9
First-level alarm (take column 2 data as an example):
A p1 ＝A+ΔA·D 1 the sum of 11.9+1.9 multiplied by 30 is 68.9um > 30um, and A is within 30 days according to the composite value and the gentle variation of the current vertical vibration amplitude of the stator core p1 Will exceed the alarm value by 30 um;
secondary alarm (take column 3 data as an example):
A p2 ＝A+ΔA·D 2 12.9+2.89 × 10 ═ 41.8um > 30um, A within 10 days according to the composite value and the gentle variation of the current vertical vibration amplitude of the stator core p2 Will exceed the alarm value by 30 um;
(13) according to the primary alarm predicted value and the secondary alarm predicted value of the highest temperature of the stator core in the step (11) and the primary alarm predicted value and the secondary alarm predicted value of the vertical polar frequency vibration composite value of the stator core in the step (12), Fourier transform is carried out on a vertical vibration signal of the stator core through a computer, and calculation is carried out Stator core vertical pole frequency vibration phase
And the phase map is used for displaying, and data analysis is visually carried out, as shown in figure 6, so as to determine the loosening direction of the lamination of the stator core;
fourier expanded signal function:
vibration phase:
in the formula: a is 0 、a n 、b n Are Fourier coefficients;
(14) comparing the data from steps (2) - (13) with the set data from step (1) as follows:
the maximum temperature value T of the stator core in the step (5) g 46.3 ℃ higher than the set normal temperature value T of the stator core z ＝46℃；
Setting the composite value A of the vertical polar frequency vibration amplitude of the stator core in the step (6) to be 10um larger than the composite value A of the vertical polar frequency vibration amplitude of the normal stator core z ＝9.9um；
Drawing a curve by taking the composite value of the maximum temperature value of the stator core and the vertical polar frequency vibration amplitude of the stator core as a vertical coordinate and time as a horizontal coordinate, and observing the curve change trend as shown in FIG. 7;
the primary alarm prediction value T of the highest temperature of the stator core, obtained in the step (11) p1 Setting a maximum temperature alarm value T for the stator core with the temperature of 55.3 ℃ > setting a ＝50℃；
The primary alarm prediction value A of the stator core vertical polar frequency vibration amplitude composite value obtained in the step (12) p1 68.9um & gt set stator core vertical polar frequency vibration alarm amplitude A a ＝30um；
The maximum temperature of the stator core is detected to be 46.3 ℃, the slow variation is detected to be 0.3, and the secondary alarm prediction value T of the maximum temperature of the stator core is detected p1 ＝55.The vertical polar frequency vibration amplitude value of the stator core is 11.9um at the temperature of 3 ℃ higher than 50 ℃, the slow variation is 1.9, and the vertical polar frequency vibration amplitude value A of the stator core p1 68.9um is more than 30um, the stator core lamination has slight loosening fault at the moment, and a first-level alarm is started; the method comprises the following steps that maintenance personnel select a machine to check and fasten the tension force or the compression density of a stator lamination of the generator and check the oil pollution condition of a generator room and the surrounding environment;
the secondary alarm prediction value T of the maximum temperature of the stator core, obtained in the step (11) p2 The maximum temperature alarm value T is set for the stator core with the temperature of 51.5 ℃ > set a ＝50℃；
The secondary alarm prediction value A of the vertical polar frequency vibration amplitude of the stator core obtained in the step (12) p2 Stator core vertical polar frequency vibration alarm amplitude A set as 41.8um ≧ a ＝30um；
Meanwhile, the stator core lamination loose azimuth angle in the step (13)
The highest temperature T of the stator core is detected to be 46.5 ℃, the slow variation is detected to be 0.50 p2 51.5 ℃ and more than 50 ℃, the vertical pole frequency vibration composite value of the stator core is 12.9um, the slow variation is 2.89, and the vertical pole frequency vibration composite value A of the stator core p2 41.8um is more than 30um, the position of the stator core lamination is loosened at 210 degrees, the vertical vibration amplitude of the stator core is 23um, the serious loosening fault of the stator core lamination occurs at the moment, a secondary alarm is started, meanwhile, a maintenance and treatment plan and measures are formulated, and the generator stator core lamination with the position of 210 degrees is treated by using a machine halt opportunity;
(15) The treatment effect is as follows:
1) after the stator laminations are loosened, 34 stator core temperature values after maintenance are again obtained from the computer monitoring system, as shown in table 10:
watch 10
Obtaining the maximum value of the temperature of the stator core after the lamination processing of the 34 stator cores:
T max ＝T 5 ＝45.7℃
the maximum temperature value T of the stator core at the moment is calculated by a three-dimensional relation model g ＝45.6℃；
2) After the stator lamination is loosened, 3 stator core vertical vibration polar frequency vibration values are obtained again from the state detection system, as shown in table 11:
TABLE 11
And calculating the composite value of the vertical polar frequency vibration of the stator core after the 3 stator core lamination processing according to the following formula:
calculating by a three-dimensional relation model, wherein the composite value A of the vertical polar frequency vibration of the stator core is 9.8 um;
after the lamination of the stator core is processed, the maximum temperature value of the stator core is 45.6 ℃, is close to the normal operation value of 46 ℃ and is less than the maximum temperature of the stator core before processing of 48.7 ℃; the stator core vertical polar frequency vibration amplitude is 9.8um, which is close to 10.0um of a normal operation value and is smaller than the stator core vertical polar frequency vibration amplitude 23um before processing, and the detection is proved to be effective, accurate and reliable.
Claims (3)
1. A hydro-generator stator core lamination loosening fault detection method is characterized by comprising the following steps:
(1) Setting the normal temperature values of all parts of the stator core of the hydroelectric generating setT z Alarm value T of maximum temperature of stator core a Normal vertical pole frequency vibration amplitude A of each part of stator core z Stator core vertical polar frequency vibration alarm value A a ；
(2) The temperature value T of the iron core of each part of the stator of the generator set is obtained through the existing temperature sensor, the active power transmitter, the current transmitter and the vibration sensor of the water-turbine generator set and the connected computer and state detection system thereof i The active power of the generator, the exciting current of the generator and the vertical polar frequency vibration amplitude of each part of the stator core;
(3) according to the temperature value T of each part of the stator core obtained in the step (2) i Finding out the maximum temperature T of the stator core max ；
(4) Obtaining the vertical polar frequency vibration amplitude A of each part of the stator core according to the step (2) i Calculating the resultant A of the vibration amplitudes of the vertical polar frequencies of the stator core according to the following formula t ：
In the formula, A t A resultant value, A, representing the amplitude of the vertical pole frequency vibration of the stator core i Representing the vertical polar frequency vibration amplitude of the stator core at the corresponding position;
(5) the highest temperature value T of the stator core found in the step (3) max And (3) establishing a mathematical model with the generator active power and the generator exciting current obtained in the step (2), and obtaining the current highest temperature value T of the stator core by using a computer, the existing mallat wavelet algorithm and a PCA data principal component analysis method g ；
(6) Establishing a mathematical model according to the active power and exciting current of the generator obtained in the step (2) and the composite value of the vertical polar frequency vibration amplitude of the iron core obtained in the step (4), and obtaining the composite value A of the current vertical polar frequency vibration amplitude of the stator iron core by using a computer, the existing mallat wavelet algorithm and a PCA data principal component analysis method;
(7) according to the current maximum temperature value T of the stator core in the step (5) g The average value of the maximum temperature of the stator core in the past 180 days is calculated according to the following formula
In the formula, T gn The maximum temperature value of the stator core is the daily average of the last 180 days;
(8) according to the composite value A of the current vertical polar frequency vibration amplitude of the stator core in the step (6), calculating the average value of the vertical polar frequency vibration amplitude of the stator core in the past 180 days according to the following formula
In the formula, A n The composite value of the daily average vertical polar frequency vibration amplitude of the past 180 days;
(9) according to the current maximum temperature value T of the stator core in the step (5) g And (7) average value of maximum temperature of stator core in past 180 days
Calculating the maximum temperature slow variable quantity delta T of the stator core according to the following formula:
(10) according to the composite value A of the current vertical polar frequency vibration amplitude of the stator core in the step (6) and the average value of the composite value A of the vertical polar frequency vibration amplitude of the stator core in the past 180 days in the step (8) 
Calculating a stator core vertical pole frequency vibration slow variation quantity delta A:
(11) according to the current highest temperature value T of the stator core in the step (5) g And (9) calculating a first-level alarm predicted value T of the highest temperature of the stator core according to the slow variation quantity delta T p1 Second-level alarm predicted value T p2 ：
T p1 ＝T g +ΔT·D 1 ；
T p2 ＝T g +ΔT·D 2 ；
Wherein D 1 、D 2 For a set number of days of early warning, D 2 ＜D 1 ；
(12) According to the composite value A of the current vertical polar frequency vibration amplitude of the stator core in the step (6) and the slow variation delta A in the step (10), calculating a primary alarm predicted value A of the vertical polar frequency vibration of the stator core p1 Second-level alarm prediction value A p2 ：
A p1 ＝A+ΔA·D 1 ；
A p2 ＝A+ΔA·D 2 ；
Wherein D 1 、D 2 To set number of days of early warning, D 2 ＜D 1 ；
(13) According to the primary alarm predicted value and the secondary alarm predicted value of the highest temperature of the stator core in the step (11) and the primary alarm predicted value and the secondary alarm predicted value of the vertical polar frequency vibration of the stator core in the step (12), performing Fourier transform on the vertical vibration amplitude of the stator core through a computer, and calculating the vertical polar frequency vibration phase of the stator core to determine the loosening direction of the lamination of the stator core;
fourier expanded signal function:
vibration phase position:
in the formula: a is 0 、a n 、b n Are Fourier coefficients;
(14) comparing the data from steps (2) - (13) with the set data from step (1) as follows:
The maximum temperature value T of the stator core in the step (5) g Stator core normal temperature value T > set z ；
The composite value A of the stator core vertical polar frequency vibration amplitude in the step (6) is larger than the set normal stator core vertical polar frequency vibration amplitude A z ；
Drawing a curve by taking the composite value of the maximum temperature value of the stator core and the vertical polar frequency vibration amplitude of the stator core as a vertical coordinate and time as a horizontal coordinate, and observing the data change trend;
the primary alarm prediction value T of the highest temperature of the stator core in the step (11) p1 Set maximum temperature alarm value T of stator core greater than set a ；
The primary alarm prediction value A of the composite value of the vertical polar frequency vibration amplitude of the stator core in the step (12) p1 Stator core vertical polar frequency vibration alarm amplitude A greater than set a ；
Detecting a slight loosening fault of the stator core lamination, and checking and fastening the tension force or the compression density of the stator lamination of the generator by a maintainer by selecting a machine, and checking oil contamination conditions of a generator room and the surrounding environment;
the secondary alarm prediction value T of the maximum temperature of the stator core in the step (11) p2 Set maximum temperature alarm value T of stator core greater than set a ；
The secondary alarm prediction value A of the composite value of the vertical polar frequency vibration amplitude of the stator core obtained in the step (12) p2 Stator core vertical polar frequency vibration alarm amplitude A greater than set a ；
And detecting the serious loosening fault of the stator core lamination, making a maintenance and treatment plan and measure, and treating the stator core lamination of the generator.
2. A method for detecting the loosening fault of the stator core lamination of a hydraulic generator according to claim 1, wherein the mathematical model of the step (5) is established through the following steps:
51) the highest temperature value T of the stator core of the generator set found in the step (3) max The active power P of the generator obtained in the step (2) is an effective value within the range of 90-250MW and the excitation current I of the generator is an effective value within the range of 1000-3600A within the range of 5-125 ℃;
52) the active power P of the generator is taken as an X coordinate, the exciting current I of the generator is taken as a Y coordinate, and the highest temperature T of the stator core is taken max Establishing a three-dimensional graph for the Z coordinate; obtaining a cross point A of a generator exciting current I and a generator active power P at the same moment on an X, Y plane of a three-dimensional graph; from the intersection A, a straight line parallel to the Z axis is formed until the maximum temperature T of the stator core is reached max The horizontal planes intersect to form a point B, and the maximum temperature value T of the stator core corresponding to the point B max I.e. the highest temperature T of the stator core at the same moment max The active power P of the generator and the exciting current I of the generator are determined through a three-dimensional relation model, and the maximum temperature value of the stator core is determined;
53) using the three-dimensional relation model of the step 52) and the maximum temperature value T of the stator core max As source data of the mallat wavelet algorithm and the PCA data principal component analysis method, the highest temperature value T of the current stator core is obtained through the existing mallat wavelet algorithm and the PCA data principal component analysis method g 。
3. A method for detecting the loosening fault of the stator core lamination of a hydraulic generator according to claim 1, wherein the mathematical model of the step (6) is established through the following steps:
61) and (4) obtaining a resultant value A of the vertical polar frequency vibration amplitude of the stator core t Is 0-50 um; the effective range of the active power P of the generator is 90-250 MW; the effective range of the generator exciting current I is 1000-3600A;
62) the active power P of the generator is taken as an X coordinate, the exciting current I of the generator is taken as a Y coordinate, and the resultant value A of the vertical polar frequency vibration amplitude of the stator core t Establishing a three-dimensional graph for the Z coordinate; obtaining a cross point A of a generator exciting current I and a generator active power P at the same moment on an X, Y plane of a graph; from the intersection point A, making a straight line parallel to the Z axis to a resultant value A of the vibration amplitude of the stator core vertical polar frequency with the Z axis t The horizontal plane is intersected to form a point B, and the resultant value A of the vertical polar frequency vibration amplitude of the stator core corresponding to the point B t I.e. the composite value A of the vertical polar frequency vibration amplitude of the stator core at the same moment t The active power P of the generator and the exciting current I of the generator are determined by a three-dimensional relation model, and the synthetic value A of the vibration amplitude of the vertical polar frequency of the stator core is determined by the three-dimensional relation model t ；
63) Using the three-dimensional relation model of the step 62) and the composite value A of the vertical polar frequency vibration amplitude of the stator core t And as source data of a mallat wavelet algorithm and a principal component analysis method of PCA data, obtaining a composite value A of the vibration amplitude of the vertical polar frequency of the current stator core by the existing mallat wavelet algorithm and the PCA data principal component analysis method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010480810.7A CN111551853B (en) | 2020-05-30 | 2020-05-30 | Hydro-generator stator core lamination loosening fault detection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010480810.7A CN111551853B (en) | 2020-05-30 | 2020-05-30 | Hydro-generator stator core lamination loosening fault detection method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111551853A CN111551853A (en) | 2020-08-18 |
| CN111551853B true CN111551853B (en) | 2022-07-29 |
Family
ID=72003585
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010480810.7A Active CN111551853B (en) | 2020-05-30 | 2020-05-30 | Hydro-generator stator core lamination loosening fault detection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111551853B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112974256A (en) * | 2021-05-20 | 2021-06-18 | 四川富生电器有限责任公司 | Stator core height automatic detection judges sieving mechanism |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100066315A1 (en) * | 2008-09-12 | 2010-03-18 | Siemens Power Generation, Inc. | Method and System for Monitoring the Condition of Generator End Windings |
| CN102721465A (en) * | 2012-06-13 | 2012-10-10 | 江苏省电力公司南京供电公司 | System and method for diagnosing and preliminarily positioning loosening faults of iron core of power transformer |
| CN103383433A (en) * | 2013-07-03 | 2013-11-06 | 中国人民解放军海军工程大学 | Method for state monitoring and early fault warning of stator core of ship generator |
| CN103439109A (en) * | 2013-09-12 | 2013-12-11 | 华北电力大学（保定） | Wind turbine generator set drive system fault early-warning method |
| CN105628421A (en) * | 2015-12-25 | 2016-06-01 | 南京南瑞集团公司 | Hydroelectric generating set vibration limit monitoring and early warning method according to working conditions |
| CN107064796A (en) * | 2017-04-20 | 2017-08-18 | 哈尔滨理工大学 | Intelligent electric machine vibration online monitoring and early warning system |
| CN110687447A (en) * | 2019-09-30 | 2020-01-14 | 华能四川水电有限公司 | Method and device for diagnosing stator core looseness, storage medium and equipment |
| CN110714869A (en) * | 2019-09-30 | 2020-01-21 | 华能四川水电有限公司 | Method and device for detecting central offset of rotor, storage medium and equipment |
-
2020
- 2020-05-30 CN CN202010480810.7A patent/CN111551853B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100066315A1 (en) * | 2008-09-12 | 2010-03-18 | Siemens Power Generation, Inc. | Method and System for Monitoring the Condition of Generator End Windings |
| CN102721465A (en) * | 2012-06-13 | 2012-10-10 | 江苏省电力公司南京供电公司 | System and method for diagnosing and preliminarily positioning loosening faults of iron core of power transformer |
| CN103383433A (en) * | 2013-07-03 | 2013-11-06 | 中国人民解放军海军工程大学 | Method for state monitoring and early fault warning of stator core of ship generator |
| CN103439109A (en) * | 2013-09-12 | 2013-12-11 | 华北电力大学（保定） | Wind turbine generator set drive system fault early-warning method |
| CN105628421A (en) * | 2015-12-25 | 2016-06-01 | 南京南瑞集团公司 | Hydroelectric generating set vibration limit monitoring and early warning method according to working conditions |
| CN107064796A (en) * | 2017-04-20 | 2017-08-18 | 哈尔滨理工大学 | Intelligent electric machine vibration online monitoring and early warning system |
| CN110687447A (en) * | 2019-09-30 | 2020-01-14 | 华能四川水电有限公司 | Method and device for diagnosing stator core looseness, storage medium and equipment |
| CN110714869A (en) * | 2019-09-30 | 2020-01-21 | 华能四川水电有限公司 | Method and device for detecting central offset of rotor, storage medium and equipment |
Non-Patent Citations (3)
| Title |
|---|
| 《基于振动信号的变压器绕组松动故障诊断方法》;颜君凯 等;《电力系统自动化》;20170210;全文 * |
| 《基于振动的变压器铁芯松动判定方法》;马宏忠 等;《电力系统自动化》;20130725;全文 * |
| 《应用复小波变换检测突发短路时的电力变压器绕组状态》;张坤 等;《电工技术学报》;20140831;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111551853A (en) | 2020-08-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6629058B2 (en) | Fault diagnosis method and apparatus | |
| Hameed et al. | Condition monitoring and fault detection of wind turbines and related algorithms: A review | |
| CN102033200B (en) | On-line monitoring and diagnosis method of AC (alternating current) motor based on statistical model | |
| Nithin et al. | Importance of condition monitoring in mechanical domain | |
| JP2006234786A (en) | Abnormality diagnostic device and abnormality diagnostic method for mechanical facility | |
| CN106441843B (en) | A kind of rotating machinery fault method for waveform identification | |
| CN111551853B (en) | Hydro-generator stator core lamination loosening fault detection method | |
| CN115539139A (en) | Method for monitoring safety of steam turbine | |
| Oscar et al. | The monitoring system of an actual technical condition for pumping units with frequency analysis | |
| Yang et al. | A case study of bearing condition monitoring using SPM | |
| CN209148192U (en) | Wind-driven generator bolt fastening stress monitoring system | |
| Saied et al. | Predictive maintenance program based on vibration monitoring | |
| CN116110203A (en) | Natural gas power generation early warning management method and system based on intelligent monitoring technology | |
| Karel et al. | Noise measurement diagnostics for large electric machines | |
| EP4209767A1 (en) | Method for diagnosing the technical condition of rotating equipment | |
| CN114754858B (en) | Shaft vibration measurement deviation tracing method based on vibration characteristic information | |
| CN111721510A (en) | Intelligent diagnosis method for steel crane beam based on real-time monitoring | |
| Wu et al. | Stress wave analysis based prognostic health management | |
| Apollonsky et al. | Diagnostics of the operation of technical means by the structure of their external electromagnetic fields | |
| He et al. | A Vibration Acceleration Sensor-based Shock Pulse Method for Condition Evaluation of Rolling Bearings | |
| Dhamande et al. | Detection of Fault in Gear Box System using Vibration Analysis Method | |
| WO2022004110A1 (en) | Rotating electrical machine damage diagnostic system and damage diagnostic method | |
| Szabo et al. | Condition Monitoring for Detecting the Malfunction of Industrial Machines | |
| CN117330137B (en) | Intelligent identification and fault detection method and system for transformer inspection image | |
| Yousaf et al. | Review of Advanced Approaches and Vibration Signature Analysis for Fault Detection, Diagnosis, and Prognosis of Rolling Element Bearings |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |