68 results about "Power transformer windings" patented technology

The invention discloses a power transformer winding insulation state monitoring method, a power transformer winding insulation state monitoring device, power transformer winding insulation state monitoring equipment and a medium, and relates to the technical field of power system equipment state monitoring. And an improved particle swarm optimization algorithm is adopted to inversely calculate the insulation parameters of a plurality of windings of the transformer to the ground, so that the insulation state of each winding can be accurately evaluated. Compared with a traditional monitoring method, the method has the advantages that rich information contained in the common-mode leakage current can be fully utilized, the insulation degradation conditions of different windings can be accurately distinguished, more accurate insulation state evaluation is provided, and the safe operation level of the transformer is effectively improved. Moreover, multi-stage evaluation is carried out on the insulation state through a fuzzy comprehensive evaluation method, the insulation state can be comprehensively reflected, different severity degrees of the insulation state can be distinguished, the current state can be evaluated, the degradation trend can be predicted through dynamic indexes, and a scientific basis is provided for operation and maintenance decision making.

The invention relates to the technical field of mechanical performance testing of power transformer winding materials, in particular to a method for evaluating the mechanical strength of a transformer winding under a reclosing working condition, and the method comprises the steps: obtaining and preprocessing historical operation data, finite element simulation data and laboratory simulation test data; deploying a micro foil strain gauge, an MEMS acceleration sensor and a flexible piezoresistive sensor based on the preprocessed data, and synchronously collecting radial strain, axial acceleration and cushion block pressure data; after noise filtering, time alignment and feature extraction, multi-directional deformation cooperative influence is analyzed through methods of Pearson's correlation coefficients, partial least square regression and the like; and in combination with a historical damage sample training evaluation model, outputting a mechanical strength degradation level in real time. According to the method, the problems of synchronous acquisition and correlation analysis of multi-direction deformation data under reclosing impact are solved, and accurate evaluation of overall mechanical strength change caused by accumulated deformation is realized.

The invention relates to the field of transformer detection, in particular to a power transformer winding deformation state detection method and system, and the method comprises the steps: obtaining a data set which comprises a three-phase winding abnormal index and a harmonic difference score of an output frequency domain signal of each phase winding, and inputting the data set into a preset prediction model to obtain the deformation state of the transformer winding. According to the method, the three-phase winding abnormal index of the linear sweep frequency domain signal is calculated, the abnormal degree of the winding is measured by using the three-phase winding abnormal index, and then the deformation state of the winding is detected by using the prediction model, so that the accuracy of a detection result is improved.

The utility model relates to the technical field of transformer production, in particular to a power transformer winding machine which comprises a U-shaped winding table, one side of the winding table is connected with a mounting rod with a rectangular section through a rotating mechanism, and a power transformer body is arranged on the mounting rod. The mounting rod is connected with the power transformer body through a fixing mechanism, the top of the winding table is fixedly connected with an L-shaped supporting rod, and the supporting rod is connected with a copper wire disc through a reciprocating lead screw. When the power transformer is used, a limiting block is pushed to move upwards through a sliding plate under the action of reset force of a second spring, the left side of the power transformer body can be limited and fixed through the limiting block, and the right side of the power transformer body can be limited and fixed through a first spring and a fixing plate; according to the power transformer, the power transformer body can stably rotate and cannot fall off from the mounting rod, so that the power transformer body can perform normal winding operation.

A method for calculating carbon emissions of oil-immersed power transformer. The method includes: obtaining operation data of the oil-immersed power transformer; determining input parameters according to the operating data; the input parameters include: a load power P of the oil-immersed power transformer, a three-phase current balance ε, and a harmonic distortion rate THD; obtaining a top oil temperature Ttop of the oil-immersed power transformer; determining an average temperature Twnd and a temperature correction coefficient Ktemp of a winding of the oil-immersed power transformer according to the top oil temperature Ttop; determining an electrical energy loss S of the oil-immersed power transformer based on the input parameters, the average temperature Twnd, and the temperature correction coefficient Ktemp; determining the carbon emission G of the oil-immersed power transformer according to the electrical energy loss S.

The invention discloses a method, a system, a medium and equipment for quickly judging the axial stability of an external short-circuit winding of a power transformer. In the method, a power transformer winding axial vibration calculation model is established; through changing a short-circuit current amplitude, a cushion block stress-strain curve characteristic value and a pre-tightening force, a critical condition of separation of a wire cake and a cushion block of a winding is obtained, and a three-dimensional map of a wire cake-cushion block vibration separation critical state is drawn. An axial stability analysis system when the power transformer is subjected to external short-circuit impact in an operation state is constructed, a computer is deployed locally to operate a calculation instruction corresponding to the method, and a short-circuit current peak value is extracted according to a current recording diagram of the power transformer under an external short-circuit fault; and determining a fault point location in the three-dimensional atlas according to the actual pre-tightening force of the winding and a cushion block stress-strain curve, and quickly judging the axial stability of the external short-circuit winding according to the relative relationship between the fault point location and a critical state interface.

The invention provides a power transformer winding mechanical fault diagnosis method based on CEEMDAN-BWO-SVM. The method comprises the following steps: S1, obtaining a vibration acceleration signal of the outer side wall of a sample power transformer box body; s2, decomposing the vibration acceleration signal by adopting a CEEMDAN method to form N IMF components; s3, calculating a Pearson's correlation coefficient of each IMF component and the initial vibration acceleration signal, and screening characteristic components based on the Pearson's correlation coefficients; s4, calculating the exponential entropy of the feature component and forming a feature vector; s5, constructing a BWO-SVM prediction model, and inputting the feature vector into the BWO-SVM prediction model for training; and S6, obtaining a vibration acceleration signal of the outer side wall of the box body of the power transformer to be detected, processing the vibration acceleration signal of the power transformer to be detected through the steps S2 to S4 to form a feature vector to be detected, and inputting the feature vector to be detected into the trained BWO-SVM prediction model to obtain a mechanical fault diagnosis result.

The invention relates to a power transformer winding deformation diagnosis positioning device and method based on pressure monitoring, and the device comprises a winding which is formed by winding a coil on an iron core, a plurality of groups of sensor modules are installed at intervals in the winding length direction of the coil, and a single group of sensor modules is wrapped in the circumferential direction of the cross section of the coil; the single-group sensor module wrapping the coil comprises turn-to-turn pressure sensors arranged oppositely and interlayer pressure sensors arranged oppositely, and the turn-to-turn pressure sensors are attached to the surface of the corresponding coil in a horizontal state in the axial direction of the iron core. The interlayer pressure sensors are attached to the surfaces of the corresponding coils in a vertical state in the radial direction of the iron core, so that a three-dimensional radar map of pressure value distribution on the winding can be formed by feedback values of the sensor modules, and deformation faults are diagnosed and positioned by continuously monitoring the pressure values on line. The overall layout and operation are simple, implementation and implementation are convenient, and the result accuracy is high.

The invention discloses a fusion filtering method, system, equipment and medium for power transformer winding state monitoring, and belongs to the technical field of power equipment state monitoring, and the method comprises the steps: obtaining an original state monitoring signal of a transformer winding; performing multi-scale decomposition on the original state monitoring signal by adopting self-adaptive wavelet transform; an improved particle filter is embedded, and a suggested distribution function of relative entropy optimization and a dynamic weight updating mechanism are combined; the filtered sub-signals are reconstructed through inverse wavelet transformation; weight parameters are adjusted in a self-adaptive mode; and outputting the key state parameters for transformer winding health assessment. Under the complex electromagnetic environment and the dynamic load fluctuation working condition, the signal-to-noise ratio of the state data of the transformer winding can be remarkably improved, the comprehensive accuracy rate of state evaluation is improved, and reliable data support is provided for health management and preventive maintenance of the transformer winding. And the operation reliability of the transformer and the intelligent level of state evaluation can be obviously improved.

The invention discloses a power transformer winding fault complex frequency domain diagnosis method and device, and the method comprises the steps: employing a neutral point voltage or current applying method, and obtaining the broadband short-circuit complex impedance of each phase of different windings of a transformer at different frequencies; according to the broadband short-circuit complex impedance of each phase of different windings under different frequencies, determining a complex frequency domain first correlation coefficient of broadband short-circuit complex impedance between different phases of different windings of the transformer under different frequencies; and performing winding fault diagnosis of the transformer according to the complex frequency domain first correlation coefficient. According to the method, the consistency of the alternating current power transformer and the converter transformer winding is detected through the correlation of the transformer winding and the complex impedance of different phases of the winding in the broadband range, weak winding faults such as winding deformation and turn-to-turn short circuit of the transformer can be found, and technical support is provided for evaluating the health state of the transformer.

The invention discloses a winding stress determination method and device of a transformer winding, equipment and a medium, and relates to the field of power transformer winding vibration stress analysis, and the method comprises the steps: determining a harmonic current component under a harmonic current of each frequency corresponding to a transformer; determining a Young modulus corresponding to the harmonic current component under the harmonic current of each frequency, and determining an electromagnetic force related to the Young modulus and corresponding to the harmonic current of each frequency; temperatures corresponding to different harmonic current components under the harmonic currents with different frequencies are the same or different; the Young modulus at different temperatures is different; calculating the single winding mechanical stress of the harmonic current of each frequency based on the Young modulus, and calculating the total winding mechanical stress; calculating a single electromagnetic stress of the harmonic current of each frequency based on the electromagnetic force, and calculating a total electromagnetic stress; and calculating the sum of the total winding mechanical stress and the total electromagnetic stress to obtain the winding stress. And the winding stress under the action of different harmonic currents can be determined.

The invention discloses a transformer winding overvoltage distribution calculation method based on an ultra-wide frequency domain model, comprising: 1) obtaining characteristic parameters of a HEMP E1 component; 2) fitting a conductor skin depth and an oil-paper dielectric response model to establish an ultra-wide frequency domain mathematical model of a transformer winding based on frequency-dependent distributed parameters; 3) establishing an ultra-wide frequency transmission line model based on frequency-dependent distributed parameters according to the ultra-wide frequency domain mathematical model of a transformer winding based on frequency-dependent distributed parameters and a multi-conductor transmission line model; 4) performing central difference processing on a transmission line equation according to the ultra-wide frequency transmission line model based on frequency-dependent distributed parameters to obtain iterative equations of voltage, current and boundary conditions, and then establishing a transmission line solution model based on the equations; 5) inputting the HEMP E1 component as a pulse source into the transmission line solution model to obtain transformer winding overvoltage distribution. The method can quickly and accurately obtain the voltage distribution of a power transformer winding under the action of HEMP E1.

The application discloses a power transformer winding and rubber coating integrated machine and a manufacturing method thereof, and belongs to the field of transformer coil production. The machine comprises a base plate, a control terminal and a winding framework. The surface of the base plate is sequentially provided with a feeding mechanism, a rotating mechanism and a winding mechanism in the horizontal direction. The feeding mechanism is provided with a horizontal moving carrying mechanism above. The winding mechanism is provided with a rubber belt support below. The self-adaptive barrier wall rubber belt with heat expansion compensation and magnetic field response characteristics is manufactured. The modified magnetorheological layer carbonyl iron powder is driven to directional arrangement by the magnetic field of the permanent magnet column during the rubber coating rotation. The penetration force of the pressure-sensitive adhesive to the coil gap is enhanced. The framework is contracted when the coil is working and heated to the preset phase change temperature. The coil thermal expansion is actively compensated. The aging of the insulation paper is avoided. The chain structure is formed in the coil magnetic field through the modified magnetorheological layer. The rubber belt hardness is improved to resist vibration impact. The heat conduction network is constructed to improve the heat dissipation efficiency.

The utility model discloses a power transformer winding outgoing line structure which comprises a copper foil body, a cutting line extending in the length direction of the copper foil body is arranged at the tail end of the copper foil body, the copper foil body is cut along the cutting line to obtain a plurality of separated foils, and the foils are kept to be connected with the copper foil body. The foils are bent and then overlapped together to form a wire outlet structure; insulation paper is wound on the outer surface of the joint of the wire outlet structure and the copper foil body, and a first bonding strip is wound on the outer surface of the insulation paper. The insulation paper is wound on the outer surface of the joint of the wire outlet structure and the copper foil body, and the insulation paper can avoid short circuit between the wire outlet structure and the iron core. By arranging the first bonding strip and the second bonding strip, the insulation paper and the foil are bonded together, the position of the insulation paper can be well fixed, and the insulation paper is prevented from sliding on the wire outlet structure.

The utility model provides power transformer winding and power transformer. Power transformer winding includes: coil cylinder body, is formed by coil cake, forms radial cooling oil channel between adjacent coil cake, inner cylinder body is formed with the inner layer cooling oil channel between coil cylinder body, and outer cylinder body is formed with the outer layer cooling oil channel between coil cylinder body, power transformer winding still includes: a plurality of support strip, is fixed to the inner circumferential surface and outer circumferential surface of coil cylinder body, and support strip has support strip connecting portion, and oil baffle ring is arranged in the inner layer cooling oil channel and / or outer layer cooling oil channel, and oil baffle ring makes the cooling oil flowing in the inner layer cooling oil channel and / or outer layer cooling oil channel change direction and flow to radial cooling oil channel, and oil baffle ring has oil baffle ring connecting portion, and oil baffle ring and support strip are fixedly connected together through the connection between oil baffle ring connecting portion and support strip connecting portion. The oil baffle ring of power transformer winding is convenient to install and improves the effect of partial oil flow resistance of winding.

The invention discloses a power transformer winding temperature on-line monitoring system. The system comprises a temperature analyzer, and an infrared thermal imager, an environment sensor group and an operation data acquisition module which are connected with the temperature analyzer; the thermal infrared imager is aligned with a monitoring area, corresponding to a winding, of a preset oil tank on the power transformer so as to collect a corresponding thermal infrared image in real time; the environment sensor group collects surrounding environment parameters of the power transformer in real time; the operation data acquisition module is arranged on an external connection cable of the power transformer so as to acquire operation data of the power transformer in real time; and the temperature analyzer receives the infrared thermogram of the monitoring area and carries out image processing so as to extract the average temperature of the monitoring area, and the average temperature is combined with the surrounding environment parameters and the operation data of the power transformer and is imported into a heat conduction model to calculate the on-line temperature of the power transformer winding. According to the invention, the problems of inconvenient installation, low precision, incapability of accurately monitoring the winding temperature in real time and the like of the existing power transformer winding temperature monitoring method can be solved.

The present invention provides a method for detecting short-circuit faults between turns of a power transformer winding, which belongs to the technical field of power equipment. The method comprises the following steps: obtaining historical short-circuit fault records between turns of a power transformer winding, identifying causes of short circuits between turns of the winding from the historical short-circuit fault records, and setting short-circuit fault detection points according to the causes; determining detection sensors based on the short-circuit fault detection points, and then creating a short-circuit fault detection map, and determining a cause map for each cause according to the short-circuit fault detection map; determining short-circuit fault features according to the short-circuit fault detection map and the cause map, establishing a fault detection model based on the short-circuit fault features, and applying the model to real-time data, judging whether a short-circuit fault exists according to the model output, and synchronously outputting a detection report to achieve accurate fault location and timely warning, and also being able to accurately identify and locate the specific causes of short-circuit faults between turns of the winding, thereby enhancing the timeliness and effectiveness of fault warning.

This invention relates to the field of power transformer technology, specifically to a power transformer winding insulation protection device and assembly method integrating temperature sensing monitoring. The device includes a housing with a protection assembly located in the middle of the housing wall. The protection assembly includes a fixed tube and a piston plate. A movable plate is connected inside the fixed tube, and the movable plate and piston plate are connected by several springs. An adjusting rod is connected inside the fixed tube. The top of the housing has an exhaust structure, including two symmetrically fixed air pipes on the left and right sides of the top of the housing. Air pipe caps are hinged to the bottom of the air pipes, and a float is fixed to the center of the bottom surface of the air pipe caps to control their rotation and closure. The air pipe caps and piston plates are connected by a cable. By incorporating the protection assembly, when an electric arc is generated, the piston plate slides forward, allowing insulating oil to flow out and release pressure. The exhaust structure, while the piston plate moves to release pressure, simultaneously opens the air pipes to discharge gas, further relieving pressure and ensuring the safe operation of the transformer.

The application discloses a kind of power transformer winding deformation diagnosis positioning method and system, transformer adopts work type optical fiber magnetic field sensor to the winding leakage magnetic field signal collection, the work type optical fiber magnetic field sensor is installed on the insulation pad between transformer winding turns;According to the leakage magnetic field situation that the work type optical fiber magnetic field sensor is continuously monitored, the winding deformation fault is diagnosed;Based on the diagnosis result of the winding deformation fault, the positioning of the winding deformation fault position is realized by establishing fitting curve expression.This application can be aimed at the problem that the accuracy of existing transformer winding deformation monitoring method is not high, and on-line monitoring technology is not mature, by using work type optical fiber magnetic field sensor and setting on the insulation pad between winding turns, the radial and axial leakage magnetic component near transformer winding is measured, the winding state of transformer can be accurately judged, and the accurate diagnosis of winding deformation fault is realized.

The invention discloses a general power transformer winding deformation frequency response detection unit. The detection unit comprises a detection unit body and a clamping device, wherein the detection unit body is arranged on a wire outlet end or an end screen tap of each winding of a to-be-detected transformer through the clamping device. A selection knob and a unit opening switch are arranged on a shell of the body, and a main control CPU, a communication module, an excitation module, a sampling module, a dial module, an excitation module switch, a sampling module switch, a grounding switch and a detection port are arranged in the shell. The dial-up module is provided with twelve static contacts, the twelve static contacts are connected to twelve I / O ports of the master control CPU respectively, and a certain static contact is controlled to be grounded through the selection knob, so that the level state of the communicated I / O ports is converted from high level to low level, and other I / O ports are kept at high level. According to the invention, the detection unit can be flexibly deployed and automatically identify phases, a winding interface does not need to be transformed, the test efficiency and the test safety are improved, and the test cost is reduced.

The application discloses a power transformer winding fault detection method based on vibration spectrum analysis and relates to the technical field of power equipment detection, which comprises the following steps: collecting original vibration acceleration signals of a transformer and preprocessing the original vibration acceleration signals to form a signal frame sequence; applying an improved Hilbert-Huang transform to each signal frame to obtain a set of intrinsic mode functions, calculating a component instantaneous frequency sequence and extracting a frequency band with an energy proportion exceeding a preset threshold as a candidate fault characteristic frequency band; extracting a subband signal of each frequency band and calculating a high-order statistical quantity feature matrix; loading a health state reference feature matrix matched with a transformer model, capacity and voltage grade; comparing the two in an element-by-element manner to identify an abnormal feature submatrix; spatially clustering the abnormal feature submatrix to form a suspected fault mode cluster; and outputting a specific winding fault mode diagnosis result. The method can accurately extract fault characteristics and improve the accuracy and reliability of fault detection.

The invention discloses a power transformer winding radial deformation judgment method and system, a medium and a product, and relates to the field of power transformers, and the method comprises the steps: carrying out a low-voltage short-circuit reactance test between power transformer winding pairs, and obtaining the short-circuit reactance between each phase of winding pair; according to the short-circuit reactance between the winding pairs of each phase and the historical short-circuit reactance between the winding pairs of each phase, the change rate of the short-circuit reactance between the winding pairs of each phase is obtained; directly measuring the capacitance between each phase of winding pair of the power transformer by adopting a bridge positive wiring method; based on the historical capacitance, the capacitance change rate between the winding pairs of each phase is determined; determining a winding deformation result according to the short-circuit reactance change rate between each phase of winding pair and the capacitance change rate between each phase of winding pair; determining the winding deformation degree according to the short-circuit reactance change rate and the short-circuit reactance threshold value between each phase of winding pair and the winding deformation result; the deformation and the deformation degree of the power transformer winding can be accurately judged.

The invention relates to the technical field of electric power, and discloses a finite element order reduction method, system, equipment and medium for rapidly solving the stress of a power transformer winding, and the method comprises the steps: obtaining the electrical physical quantity related to the power transformer winding, and carrying out the three-dimensional entity model building of a power transformer, performing spatial order reduction on the three-dimensional solid model to obtain a two-dimensional axisymmetric finite element calculation model of the power transformer; carrying out initial grid division on the solution domain, and carrying out finite element numerical calculation solution on an internal electromagnetic field of the power transformer under various operation conditions to obtain electrodynamic force density data; and solving the stress distribution of the power transformer winding under the corresponding working condition, and generating a response surface model for calculating the stress of the power transformer winding. According to the method, the effects of reducing the calculation dimension, reducing the calculation amount and saving the calculation time and CPU load can be achieved, the calculation rapidity and accuracy of the reduced-order model are proved, and a basis and an optimization thought are provided for stress analysis and solution of the power transformer.

The present invention relates to the field of fault diagnosis technology, and specifically to a transformer mechanical instability fault diagnosis method, device and electronic equipment, including: collecting the voiceprint vibration signal of the transformer, preprocessing the voiceprint vibration signal, then calculating the average complexity of the voiceprint vibration signal, normalizing the average complexity of the voiceprint vibration signal to obtain the relative complexity of the voiceprint vibration signal, and determining the transformer mechanical instability fault based on the relative complexity of the voiceprint vibration signal. The present invention realizes the overall mechanical stability monitoring of each transformer winding, improves the overall coverage and performance of the transformer winding mechanical stability monitoring system; and adopts the transformer vibration signal frequency spectrum solution algorithm to establish a transformer vibration frequency domain signal complexity description method, and establishes a winding structure instability fault diagnosis standard based on complexity description, thereby realizing accurate diagnosis of large power transformer winding structure instability faults.

The application discloses an oscillation wave detection-based extra-high voltage power transformer winding fault simulation device and diagnosis method. Firstly, the test transformer winding is tested, the transformer winding connection point is connected with a high-frequency high-voltage switch and a high-frequency high-voltage direct current power supply, the high-frequency high-voltage switch is periodically actuated, thereby exciting the extra-high voltage transformer body structure vibration; according to the test data, an ITD transformation is adopted to establish a signal model X t ; then, an empirical mode decomposition (EMD) method is adopted to decompose the signal into a sum of a plurality of mutually orthogonal intrinsic mode function (IMF) components, a Hilbert transformation is performed on each IMF component to obtain an instantaneous frequency and an instantaneous amplitude, thereby obtaining a Hilbert spectrum of the signal to perform decomposition and reconstruction, improve the signal-to-noise ratio, calculate I(X,Y) to judge and remove most of the redundant noise and interference signals; further reconstruct the required signal, after the EMD decomposition of the non-steady-state signal, the mutual information is utilized to screen the obtained IMF components of each order, and a new x(t) is obtained. Finally, the winding vibration signal after the simulation deformation fault is solved through a signal sequence sample entropy calculation formula, and the winding deformation fault severity is judged, and the transformer fault degree is identified.

The present application relates to the technical field of power transformer winding deformation detection, and particularly relates to a transformer winding deformation diagnosis method and system based on credibility and consistency verification, taking phase or phase group as an evaluation unit, performing consistency verification on the test configuration of current test data and review test data to form an effective test data pair, calculating the test credibility of frequency response and short-circuit impedance and determining the main credibility abnormal contribution item. The data reaching the threshold value is compared with the reference data to obtain the frequency response abnormal score and impedance abnormal score, and the substandard data does not participate in fusion and generates a recovery-oriented retest. When both types of tests are credible, the cross-test result difference is calculated, the winding deformation level is fused and output when the consistency threshold is met, otherwise a verification-oriented retest is generated. The retest data is updated after the credibility is confirmed, and the diagnosis result is output. The present application realizes traceable and terminable closed-loop diagnosis through configuration verification, credibility gating and differential retest.

The invention relates to the technical field of winding equipment, discloses oil-immersed power transformer winding equipment, and solves the problems that coils produced by existing oil-immersed transformer coil winding equipment are loose, and short circuit is easily caused when an oil-immersed transformer is used. Oil-immersed power transformer winding equipment comprises a machining table, a fixing shell, a first electric telescopic rod and a guide block, a pressing assembly is arranged at the upper end of the machining table, a winding assembly is arranged on one side of the fixing shell, the pressing assembly comprises a fixing plate, an elastic component, an extrusion component, a pressing arc plate and a clamping component, the elastic component is arranged on one side of the fixing plate, and the clamping component is arranged on the other side of the fixing plate. The elastic component is arranged on one side of the fixing plate, the extrusion component is arranged on the other side of the fixing plate, the pressing arc plate is arranged at the other end of the elastic component, the clamping component is arranged on one side of the pressing arc plate, and through the arrangement of the fixing plate, the elastic component, the extrusion component, the pressing arc plate and the clamping component, the purpose of preventing copper wires on the winding former from loosening is achieved.

The invention relates to an improved winding machine welding set, in particular to a winding machine used for producing middle-high voltage power transformer windings for power generation, power transmission and power distribution.

A power transformer external short-circuit winding axial stability rapid judgment method, system, medium and equipment. In the method, a power transformer winding axial vibration calculation model is established; by changing the short-circuit current amplitude, the characteristic value of the stress-strain curve of the cushion block and the pre-tightening force, the critical condition of the separation of the line pie and the cushion block of the winding is obtained, and the three-dimensional atlas of the critical state of the vibration separation of the line pie-cushion block is drawn. An axial stability analysis system of the power transformer under the external short-circuit impact in the running state is constructed, the above method corresponding calculation instruction is run by the local deployment computer, the short-circuit current peak value is extracted according to the current recording wave graph under the external short-circuit fault of the power transformer, and the fault point is determined in the three-dimensional atlas according to the actual pre-tightening force of the winding and the stress-strain curve of the cushion block. According to the relative relationship between the fault point and the critical state interface, the axial stability of the external short-circuit winding is rapidly judged.

The invention discloses an extra-high voltage power transformer winding fault simulation device and diagnosis method based on oscillatory wave detection, and the method comprises the steps: firstly testing a test transformer winding, connecting a connection point of the transformer winding with a high-frequency high-voltage switch and a high-frequency high-voltage DC power supply, and enabling the high-frequency high-voltage switch to carry out the periodic operation; therefore, the extra-high-voltage transformer body structure is excited to vibrate; establishing a signal model Xt by adopting ITD transformation according to the test data; the method comprises the following steps of: firstly, acquiring a signal, then decomposing the signal into the sum of a plurality of mutually orthogonal intrinsic mode function (IMF) components by adopting an empirical mode decomposition (EMD) method, and then performing Hilbert transformation on each IMF component to obtain an instantaneous frequency and an instantaneous amplitude, thereby obtaining a Hilbert spectrum of the signal to perform decomposition and reconstruction, improving a signal-to-noise ratio and solving I (X, Y) to judge and remove most of redundant noise and interference signals; and further reconstructing the required signal, and screening the obtained IMF components of each order by using mutual information after the unsteady-state signal is decomposed by EMD to obtain a new x (t). And finally, solving a winding vibration signal after the deformation fault is simulated through a solved signal sequence sample entropy calculation formula, judging whether the deformation fault of the winding is serious according to the winding vibration signal, and identifying the fault degree of the transformer.