CN-121993334-A - Water turbine generator set axis measuring device and method

CN121993334ACN 121993334 ACN121993334 ACN 121993334ACN-121993334-A

Abstract

The invention discloses a method and a system for on-line monitoring of the stress characteristics of a hydroelectric generating set, wherein the method comprises the following steps: a01: the stress data is collected in a multi-dimensional mode; a02: carrying out multi-source data fusion pretreatment; a03: stress characteristics are adaptively extracted, and A04: modeling and evaluating stress states; a05: the system comprises an intelligent sensing node of the Internet of things, a data preprocessing module, a feature extraction module, a state evaluation module, an early warning feedback module and a digital twin calibration module; according to the invention, a SVM-LSTM hybrid model is used, a normal state classifier is established by the SVM module, the LSTM module outputs a stress prediction value and calculates the deviation degree, the hybrid model combines the SVM classification advantage and the LSTM prediction capability, a normal state benchmark is accurately established, the real-time stress state deviation degree is quantized, a scientific basis is provided for state evaluation, the evaluation result is compared with a digital twin model simulation stress value, and model parameters are corrected.

Inventors

MENG PENG
WANG DAQUAN
ZHAO LEI
XU WEIXIAN
LIU PENGFEI
WANG HONGTENG
SUN BO
FENG JIANJUN
XU YANHE
WANG LEI
BAI GUANGHUI

Assignees

华电电力科学研究院有限公司

Dates

Publication Date: 20260508
Application Date: 20251229

Claims (10)

1. The axis measuring device of the hydroelectric generating set is characterized by taking the X/Y direction as a measuring position reference and comprising an eddy current displacement sensor, an L-shaped angle iron reference base, a data acquisition unit and an analysis processing unit combined with a computer system; the reference base is fixed in the X and Y directions of four plane positions of the upper guide, the lower guide, the flange and the water guide of the unit; The eddy current displacement sensor is fixed on the reference base and is connected with the data acquisition device through a three-phase shielding wire; the analysis processing unit can process the acquired signals to acquire shafting related data.
2. The axis measuring device of a hydroelectric generating set according to claim 1, wherein the reference base is L-shaped angle iron and is fixed on two X and Y directions which are 90 degrees with each other at four plane positions of an upper guide, a lower guide, a flange and a water guide, the upper guide X, the upper guide Y, the lower guide X, the lower guide Y, the flange X, the flange Y, the water guide X and the water guide Y are respectively placed on one, the reference base is fixed on a non-rotating position close to the water turbine, the generator and the like through a fixed adhesive or a magnetic base, and an adjusting mechanism is arranged on the reference base.
3. The axial line measuring device of a hydroelectric generating set according to claim 1, wherein the eddy current displacement sensors are fastened by fastening bolts on two sides of the L angle iron in opposite directions through bolt through holes penetrating through the L angle iron, so as to be fixed on a reference base, each eddy current displacement sensor is provided with an adjusting bolt, the adjusting bolts are matched with the base through holes to realize horizontal distance adjustment, the signal output of each eddy current displacement sensor is voltage output, the distance between the sensor and the surface of the shaft is measured through an electromagnetic induction coil in the rotating process of the rotating shaft, and the distance from the surface of the rotating shaft during measurement enables the sensor display value to be a preset value, so that the measured data is ensured to be in a range.
4. The axial line measuring device of the hydroelectric generating set according to claim 1, wherein the eddy current displacement sensor adopts an electromagnetic induction principle to measure, high-frequency oscillating current in a front-end processor in the sensor system flows into a probe coil through an extension cable to generate an alternating magnetic field at a head coil of the probe, when a measured metal body approaches to the magnetic field, induced current is generated on the surface of the measured metal body, meanwhile, the eddy current field generates an alternating magnetic field opposite to the direction of the head coil, the change of the distance between the head coil and the metal conductor is converted into the change of voltage or current, and the output signal changes along with the distance between the probe and the surface of the measured metal body, so that the measurement of the displacement parameter of the metal body is realized.
5. The axis measuring device of the hydroelectric generating set according to claim 1, wherein the data collector is connected with the eddy current displacement sensor through a three-phase shielding line, receives the X/Y direction voltage signals of the upper guide, the lower guide, the flange and the water guide of the set, continuously records the displacement voltage signals of the eddy current step by step, the sampling frequency is not lower than a preset frequency, and after the data are obtained, the frequency filtering function is selected to filter out high-frequency clutter interference data.
6. The axis measuring device of the hydroelectric generating set according to claim 1, wherein the analyzing and processing unit obtains bearing deflection data of each part of the complete cycle through tracing, the upper guide is used as a reference object, the lower guide, the flange and the water guide deflection are removed at the same time period, the upper guide deflection is corrected, the deflection of three parts relative to the upper guide is obtained, and shafting deflection angles of each part are obtained through conversion, so that whether shafting deflection reaches the standard is judged.
7. A method for measuring the axis of a hydroelectric generating set, which is applicable to a hydroelectric generating set axis measuring device according to any of claims 1 to 6, characterized in that the method comprises the following specific steps: The L-shaped angle iron reference base is fixed at the positions of an upper guide X, an upper guide Y, a lower guide X, a lower guide Y, a flange X, a flange Y, a water guide X and a water guide Y through a fixing glue or a magnetic base, and key phase blocks are arranged at the positions of the water guide X; Selecting a machine set fall-down shutdown process, ensuring that braking is not input, starting a data acquisition program when the rotating speed is reduced below a preset proportion of a rated rotating speed, and triggering a complete period data recording mechanism by using a key phase block; The dynamic data acquisition, wherein the data acquisition device continuously records voltage signals output by each sensor at a preset sampling frequency, synchronously stores key phase marking information to form an original data set containing a time stamp, and the acquisition duration covers at least 3 complete rotation periods; The analysis processing unit processes the acquired data, utilizes a frequency filtering function to filter high-frequency clutter interference data, obtains bearing deflection data of each part of a complete cycle through trace tracing, converts a voltage signal into a corresponding deflection displacement signal, corrects the deflection data of a lower guide, a flange and a water guide by taking the upper guide as a reference, eliminates the influence of the upper guide on the deflection data, converts the shafting deflection angle of each part according to the corrected deflection data, and judges whether shafting deflection reaches the standard.
8. The method for measuring axis of hydroelectric generating set according to claim 7, wherein in the data analysis and evaluation step, the voltage signal is converted into a swing displacement signal, and the conversion formula is as follows: , Wherein, the Is a swing displacement signal, namely the actual swing value of the upper guide, the lower guide, the flange and the water guide in the X/Y direction, For the conversion factor, determined by an eddy current sensor calibration experiment, A real-time voltage signal received by the data collector, As the reference value of the initial voltage, The initial displacement reference value is the initial distance between the sensor and the rotating shaft surface.
9. The method for measuring the axis of a hydroelectric generating set according to claim 7, wherein the above guide is used as a reference to correct the swing degree data of the down guide, the flange and the water guide, and the correction formula is as follows: , Wherein, the Is the first The relative degree of swing of each measuring part relative to the upper guide, Is the first The absolute degree of rocking of the individual parts, Is the first The distance between each part and the fixed datum point of the unit, For the distance between the upper guide and the fixed datum point of the unit, Is the absolute swing of the upper guide.
10. The method for measuring the axis of a hydroelectric generating set according to claim 7, wherein the shafting deflection angle of each part is converted according to the corrected swing data, and the conversion formula is as follows: , Wherein, the Is the first The shaft system of each part deflects by an angle, Is the first The relative swaying degree of each part in the X direction, Is the first The relative swaying degree of each part in the Y direction, Is the first Axial distance between the respective location and the upper guide.

Description

Water turbine generator set axis measuring device and method Technical Field The invention relates to the technical field of generator overhaul, in particular to a device and a method for measuring the axis of a hydroelectric generating set. Background The axis measurement adjustment of the hydroelectric generating set is an important content of set installation, overhaul and maintenance, and the axis adjustment has the significance that the ideal states of three lines of the set axis, the set center line and the main shaft placement center line are respectively vertical and coincide, in the ideal state, the swing degree is not generated in the set rotating process under the condition that the three lines coincide, but in the actual process, three-line integration cannot be realized, and only the deviation of each line can be ensured to be within the standard allowable range. At present, when the relative swing degree of each part of a hydroelectric generating set is measured by a power plant, a turning mode is generally adopted, and data is recorded by using a mechanical dial indicator, but the method has a plurality of remarkable defects that firstly, the measurement data error is large, the precision of the mechanical dial indicator can only reach 10-20um, the strict requirement of the modern hydroelectric generating set on the measurement precision is difficult to meet, the actual state of an axis cannot be truly reflected by a measurement result, secondly, in the turning measurement process, the data on the mechanical dial indicator needs to be manually read, the process is easily influenced by human factors, such as visual errors in reading and pen errors in recording, and the like, the accuracy of the measurement data is further reduced, thirdly, the number of the measurement points is limited, only 8 measurement points are generally arranged in one circle of the turning, and the most real swing degree condition of the axis in the rotation process cannot be comprehensively and accurately captured due to sparse measurement point distribution, so that the finally obtained data and the real axis data have larger deviation, and the turning device has the problems of large volume and complex operation, the labor is increased, the cost is increased, and the maintenance schedule cannot be easily influenced by the generating set, and the maintenance schedule is not influenced. Disclosure of Invention The invention aims to make up the defects of the prior art, provides a device and a method for measuring the axis of a hydroelectric generating set, effectively solves the problems of low precision, labor and time consumption and the like of the traditional measuring method, and has remarkable innovation and practicability. The invention provides the following technical scheme for solving the technical problems: On the one hand, the axis measuring device of the hydroelectric generating set takes the X/Y direction as a measuring position reference, and consists of an eddy current displacement sensor, an L-shaped angle iron reference base, a data acquisition unit and an analysis processing unit combined with a computer system; the reference base is fixed in the X and Y directions of four plane positions of the upper guide, the lower guide, the flange and the water guide of the unit; The eddy current displacement sensor is fixed on the reference base and is connected with the data acquisition device through a three-phase shielding wire; the analysis processing unit can process the acquired signals to acquire shafting related data. Further, the reference base is L-shaped angle iron, is fixed on two X and Y directions which are 90 degrees in each other at the upper guide, the lower guide, the flange and the water guide, one is respectively placed at the upper guide X, the upper guide Y, the lower guide X, the lower guide Y, the flange X, the flange Y, the water guide X and the water guide Y, and the reference base is fixed on a non-rotating position close to a water turbine, a generator and the like through a fixed adhesive or a magnetic base, and is provided with an adjusting mechanism. Still further, the eddy current displacement sensor is fastened in opposite directions on two sides of the L angle iron through the bolt through hole penetrating through the L angle iron by the fastening bolts, so that the eddy current displacement sensor is fixed on the reference base, each eddy current displacement sensor is provided with an adjusting bolt and matched with the base through hole to realize horizontal distance adjustment, the eddy current displacement sensor is provided with-24V power supply, signal output is voltage output, the distance between the sensor and the shaft surface is measured through the electromagnetic induction coil in the rotating process of the rotating shaft, and the distance from the rotating shaft surface during measurement enables the sensor display value to be 10V so as to ensure that measured