Converter transformer partial discharge online monitoring and early warning method and system based on optical fiber acoustic signal

Abstract

The invention discloses a converter transformer partial discharge online monitoring and early warning method and system based on optical fiber acoustic signals, and belongs to the technical field of power transmission and transformation equipment online monitoring. The method comprises the steps of performing online monitoring on a target converter transformer based on an optical fiber acoustic sensor, and obtaining optical fiber acoustic signals of the target converter transformer in the whole process from typical defect discharge starting to breakdown; and extracting characteristic parameters in the optical fiber acoustic signal, and sending out partial discharge early warning of the converter transformer according to the characteristic parameters based on a preset early warning strategy. According to the invention, an active defense system is constructed for the converter transformer, and reliable early warning before internal discharge breakdown of the converter transformer is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of on-line monitoring of power transmission and transformation equipment, and more specifically, to an on-line monitoring and early warning method and system for converter transformer partial discharge based on optical fiber acoustic signals. Background Art

[0002] Converter transformers are core equipment in high-voltage direct current (HVDC) transmission systems. When a fault occurs inside a converter transformer, if the protection device fails to act in time, it may cause damage to the converter transformer body due to the pressure shock caused by the internal fault, and even lead to serious accidents such as explosion or fire. These potential hazards pose a severe challenge to the safe and stable operation of the HVDC transmission system. However, the existing differential current protection and mechanical gas protection are difficult to comprehensively ensure the safe and stable operation of the converter transformer body, and are even more difficult to sensitively and reliably detect minor faults or potential serious defects of the converter transformer. Therefore, it is urgent to strengthen the comprehensive perception and intelligent analysis of the state of converter transformer equipment to effectively improve its fault early warning and operation safety capabilities.

[0003] Condition monitoring is a key technical means for early warning of potential defects in converter transformers. At present, the condition monitoring and diagnosis of converter transformers mainly rely on oil chromatogram monitoring devices and partial discharge monitoring devices. Oil chromatogram on-line monitoring equipment usually includes a highly reliable oil chromatogram device, a single hydrogen gas monitoring device, and a single acetylene gas monitoring device. However, since it takes a certain amount of time for the processes of oil inlet and return, degassing, and detection, and these processes cannot be compressed or omitted, the detection period of the oil chromatogram on-line monitoring equipment in current UHV operation is 2 hours, which limits its early warning ability for sudden faults to a certain extent. Summary of the Invention

[0004] In view of the above problems, the present invention proposes an on-line monitoring and early warning method for converter transformer partial discharge based on optical fiber acoustic signals, including:

[0005] On-line monitoring of a target converter transformer based on an optical fiber acoustic sensor, and obtaining optical fiber acoustic signals of the whole process from the start to breakdown of typical defect discharges of the target converter transformer;

[0006] Extracting characteristic parameters from the optical fiber acoustic signals, and issuing a partial discharge early warning for the converter transformer based on the preset early warning strategy according to the characteristic parameters.

[0007] Optionally, the preset early warning strategy includes:

[0008] Obtaining the characteristic laws of each stage of defect discharge of the converter transformer, and formulating an early warning strategy based on the characteristic laws.

[0009] Optionally, obtaining the characteristic laws of each stage of defect discharge of the converter transformer includes:

[0010] Set up a typical defect model inside the full-scale converter transformer model, and simulate the process of the typical defect of the converter transformer from the initial discharge to the arc breakdown to obtain simulation test data. Based on the simulation test data, obtain the characteristic laws of each stage of the defect discharge of the converter transformer.

[0011] Optionally, the typical defect model includes at least one of the following:

[0012] Point discharge model, floating discharge model and surface discharge model.

[0013] Optionally, when simulating the process of the typical defect of the converter transformer from the initial discharge to the arc breakdown, the voltage boosting method adopts a combination of constant voltage boosting and stepped voltage boosting.

[0014] Optionally, the process of the typical defect from the initial discharge to the arc breakdown includes:

[0015] Discharge initiation stage, discharge development stage and discharge severe until breakdown stage.

[0016] Optionally, the characteristic laws include:

[0017] The characteristic laws of the average value of the partial discharge signal amplitude, the discharge pulse frequency and the amplitude change rate during the discharge development process.

[0018] Optionally, the early warning strategy includes: partial discharge early warning logic;

[0019] The partial discharge early warning logic includes:

[0020] When in the later stage of discharge development, the average amplitude of the discharge signal shows the characteristic laws of overall rise, local fall and spike before breakdown, and when any two of the three characteristic parameters of the average amplitude value, discharge pulse frequency and amplitude change rate exceed the limit value, issue a partial discharge early warning.

[0021] On the other hand, the present invention also proposes an on-line monitoring and early warning system for converter transformer partial discharge based on optical fiber acoustic signals, including:

[0022] An on-line monitoring unit for on-line monitoring of the target converter transformer based on an optical fiber acoustic sensor and obtaining the optical fiber acoustic signals of the whole process of the typical defect discharge initiation to breakdown of the target converter transformer;

[0023] An early warning unit for extracting the characteristic parameters from the optical fiber acoustic signals and issuing a partial discharge early warning of the converter transformer based on the preset early warning strategy according to the characteristic parameters.

[0024] Optionally, the on-line early warning system for converter transformer partial discharge further includes:

[0025] A strategy formulation unit, configured to obtain the characteristic laws of each stage of the defective discharge of a converter transformer, and formulate a warning strategy based on the characteristic laws.

[0026] Optionally, obtaining the characteristic laws of each stage of the defective discharge of a converter transformer includes:

[0027] Setting a typical defect model inside a full-scale converter transformer model, and simulating the process of the typical defect of the converter transformer from the initial discharge to the arc breakdown to obtain simulation test data, and obtaining the characteristic laws of each stage of the defective discharge of the converter transformer based on the simulation test data.

[0028] Optionally, the typical defect model includes at least one of the following:

[0029] Point discharge model, suspended discharge model and surface discharge model.

[0030] Optionally, when simulating the process of the typical defect of the converter transformer from the initial discharge to the arc breakdown, the voltage boosting method adopts a combination of constant voltage boosting and stepped voltage boosting.

[0031] Optionally, the process of the typical defect from the initial discharge to the arc breakdown includes:

[0032] Discharge initiation stage, discharge development stage and discharge severity until breakdown stage.

[0033] Optionally, the characteristic laws include:

[0034] The characteristic laws of the average value of the partial discharge signal amplitude, the discharge pulse frequency and the amplitude change rate during the discharge development process.

[0035] Optionally, the warning strategy includes: partial discharge warning logic;

[0036] The partial discharge warning logic includes:

[0037] When in the later stage of discharge development, the average amplitude of the discharge signal shows the characteristic laws of overall rise, local fall and sharp rise before breakdown, and any two of the three characteristic parameters of the average amplitude value, the discharge pulse frequency and the amplitude change rate exceed the limit value, a partial discharge warning is issued.

[0038] On the other hand, the present invention also provides a computing device, including: one or more processors;

[0039] The processor is configured to execute one or more programs;

[0040] When the one or more programs are executed by the one or more processors, the method as described above is implemented.

[0041] On the other hand, the present invention also provides a computer-readable storage medium with a computer program stored thereon. When the computer program is executed, the method described above is implemented.

[0042] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0043] The present invention provides an on-line monitoring and early warning method for converter transformer partial discharge based on optical fiber acoustic signals, including: on-line monitoring of a target converter transformer based on an optical fiber acoustic sensor, and obtaining optical fiber acoustic signals of the whole process from the start to breakdown of typical defects of the target converter transformer; extracting characteristic parameters from the optical fiber acoustic signals, and based on a preset early warning strategy, issuing a partial discharge early warning for the converter transformer according to the characteristic parameters. The present invention constructs an active defense system for the converter transformer and realizes reliable early warning before internal discharge breakdown of the converter transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a flowchart of the method of the present invention;

[0045] Figure 2 is a schematic diagram of the installation position of the built-in acoustic sensor of the converter transformer in the embodiment of the method of the present invention;

[0046] Figure 3 is a schematic diagram of the average discharge amplitude of the acoustic signal in the embodiment of the method of the present invention;

[0047] Figure 4 is a schematic diagram of the discharge frequency of the acoustic signal in the embodiment of the method of the present invention;

[0048] Figure 5 is a schematic diagram of the change in the time-domain and frequency-domain distributions of the acoustic signal during the discharge development process in the embodiment of the method of the present invention;

[0049] Figure 6 is a schematic diagram of the "concave curve + two out of three" early warning strategy in the embodiment of the method of the present invention;

[0050] Figure 7 is a structural diagram of the system of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0051] Now, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely, and to fully convey the scope of the present invention to those skilled in the art. The terms in the exemplary embodiments shown in the drawings are not limitations on the present invention. In the drawings, the same unit / element is denoted by the same reference numeral.

[0052] Unless otherwise specified, the terms (including technical terms) used herein have the ordinary meaning understood by those skilled in the art. In addition, it can be understood that the terms defined in the commonly used dictionary should be understood as having a meaning consistent with the context of the relevant field, and should not be understood as idealized or overly formal meanings.

[0053] Embodiment 1:

[0054] The present invention proposes an on-line monitoring and early warning method for converter transformer partial discharge based on fiber optic acoustic signals, as Figure 1 shown, including:

[0055] Step 1: Based on the fiber optic acoustic sensor, conduct on-line monitoring of the target converter transformer, and obtain the fiber optic acoustic signals of the whole process from the start of typical defect discharge to breakdown of the target converter transformer;

[0056] Step 2: Extract the characteristic parameters from the fiber optic acoustic signals, and based on the preset early warning strategy, issue an early warning of partial discharge of the converter transformer according to the characteristic parameters.

[0057] Among them, the preset early warning strategy includes:

[0058] Obtain the characteristic laws of each stage of converter transformer defect discharge, and formulate an early warning strategy based on the characteristic laws.

[0059] Among them, obtaining the characteristic laws of each stage of converter transformer defect discharge includes:

[0060] Set a typical defect model inside the prototype converter transformer model, and simulate the process of typical defects of the converter transformer from the start of discharge to arc breakdown to obtain simulation test data. Based on the simulation test data, obtain the characteristic laws of each stage of converter transformer defect discharge.

[0061] Among them, the typical defect model includes at least one of the following:

[0062] Tip discharge model, floating discharge model and surface discharge model.

[0063] Among them, when simulating the process of typical defects of the converter transformer from the start of discharge to arc breakdown, the voltage boosting method adopts a combination of constant voltage boosting and step voltage boosting.

[0064] Among them, the process of typical defects from the start of discharge to arc breakdown includes:

[0065] Discharge start stage, discharge development stage and discharge severe until breakdown stage.

[0066] Among them, the characteristic laws include:

[0067] The characteristic laws of the average amplitude value, the discharge pulse frequency, and the amplitude change rate of the partial discharge signal during the discharge development process.

[0068] Among them, the early warning strategy includes: the partial discharge early warning logic;

[0069] The partial discharge early warning logic includes:

[0070] When in the later stage of discharge development, the average amplitude of the discharge signal shows the characteristic laws of overall increase, local decline, and sharp rise before breakdown, and when any two of the three characteristic parameters of the average amplitude value, the discharge pulse frequency, and the amplitude change rate exceed the limit value, a partial discharge early warning is issued.

[0071] Among them, the present invention simulates the process from the initial discharge to the arc breakdown of typical defects on a full-scale converter transformer fault simulation platform, uses an in-built fiber optic acoustic sensor to receive the fiber optic acoustic signals when partial discharge occurs inside the converter transformer, extracts the characteristic parameters representing the whole process of the occurrence, development, and breakdown of different types of partial discharges, obtains the characteristic laws of each stage of the defect discharge, and supports the establishment of the fault laws and characterization, fault early warning, and active defense system of the converter transformer.

[0072] The present invention sets up typical defect models such as tip discharge, floating discharge, and surface discharge inside the transformed full-scale transformer model, and the voltage boosting process adopts a combination of constant voltage boosting and step voltage boosting. The signals of the whole process from the start of discharge to breakdown of the typical defect are collected by the in-built fiber optic acoustic sensor, the characteristic laws of the partial discharge signal with the development of the defect are summarized according to the discharge test data of the full-scale transformer, and the early warning strategy is formulated.

[0073] The typical defect models include tip discharge, floating discharge, and surface discharge. The tip discharge defect model consists of a needle tip and a thick cardboard, and the needle tip is the high-voltage electrode; the floating discharge consists of a floating electrode and a flat ground electrode; the surface discharge model consists of upper and lower cylindrical electrodes and cardboard. The distance between the defect high-voltage electrode and the ground electrode is adjustable, and the discharge amount is above 1000 pC when a voltage of 20 kV is applied between the two electrodes, and breakdown can occur when a voltage higher than 30 kV (30 - 50 kV) is applied.

[0074] The voltage boosting method is carried out by combining constant voltage boosting and step voltage boosting. During the test, the transformer is boosted to the specified voltage, and at this time, the defect model generates a preset discharge amount. Constant voltage is applied for 1 hour. If the defect model does not break down, then the step voltage boosting method is adopted later, boosting in steps of 2 kV, and staying at each voltage level for 3 - 5 minutes until the fault breaks down.

[0075] The built-in fiber optic acoustic sensor for collecting partial discharge signals inside the converter transformer is small in size, fast in response speed, good in insulation, high in detection sensitivity and good in multiplexing. The measurement frequency band of the built-in fiber optic acoustic sensor is usually 10 - 60 kHz, and the dynamic range is 60 - 120 dB. The sensor is connected to the tank body, avoiding the influence of the tank shielding structure on the transmission attenuation of the acoustic signal, and the effective monitoring range of the sensor is wide; as the discharge process develops, the distribution of the detection frequency band changes, and in the frequency domain, it moves to the audible frequency band in the arc discharge stage.

[0076] The characteristic parameters in the development process of the partial discharge signal include the average amplitude value, the amplitude change rate, and the discharge pulse frequency. Further, for the average amplitude value, since the step change of the amplitude will cause a large increase in the average amplitude, the amplitude fluctuation after the amplitude jump should be considered when designing the limit value of the average amplitude; for the amplitude change rate, when calculating the partial discharge amplitude change rate, the slopes of various step lengths (considering intervals of 1 point, 5 points, and 10 points) should be considered, and different limit values of the slope should be set according to different step lengths; the setting of the limit values of the characteristic parameters should be gradually iteratively optimized according to the test results to improve the sensitivity and reliability of the partial discharge signal detection.

[0077] The typical defect discharge stages include the discharge initiation stage, the discharge development stage, and the discharge severe stage until breakdown, a total of three stages.

[0078] In different development stages of the typical defect, the acoustic partial discharge signals all have the development law of overall increase, local decline, and a sharp rise before breakdown. The overall growth amplitude of the acoustic signal in the oil-paper discharge process is relatively large, and the overall growth amplitude of the acoustic signal in the oil-gap discharge process is relatively small. Specifically, the average amplitude of the acoustic signal fluctuates and increases throughout the discharge process; in the middle and early stages of the discharge, the discharge frequency rises steadily; in the later stage of the discharge, the discharge frequency is stable; a downward trend appears before approaching breakdown. As the discharge develops, the amplitude and frequency of the pulse signal increase significantly, and the low-frequency component of the signal frequency band distribution increases.

[0079] According to the characteristic law that the average amplitude value, the discharge pulse frequency, and the amplitude change rate of the partial discharge signal generally show an increasing trend during the discharge development process, the partial discharge early warning logic of "concave curve + two out of three" is designed for the early warning strategy. The "concave curve" means that in the later stage of the discharge development, the average amplitude of the discharge signal shows the characteristic law of overall increase, local decline, and a sharp rise before breakdown. The "two out of three" means that any two of the three characteristic parameters of the average amplitude value, the discharge pulse frequency, and the amplitude change rate exceed the limit value.

[0080] The following is further illustrated with examples:

[0081] In this embodiment, the fiber optic acoustic sensor for receiving the partial discharge signal inside the converter transformer is installed at the B-phase support of a full-scale transformer (rated voltage 66 kV), as Figure 2As shown in the figure. The internal defect of the converter transformer is tip discharge. The tip electrode is the high-voltage electrode. To prevent the breakdown of the oil gap, a 1-mm-thick cardboard is added between the ground electrode disc and the tip of the needle. The distance between the tip of the needle and the cardboard is about 2 mm. The entire discharge process belongs to oil-gap discharge.

[0082] Further, during the test, first raise the voltage of the transformer to 10 kV and keep the voltage constant for 1 hour, and no breakdown occurs in the defect model; when the voltage is raised to 32 kV (corresponding to the electrode voltage of 30.4 kV) by the step voltage increase method, an instantaneous arc discharge phenomenon occurs; continue to raise the voltage step by step to 34 kV (corresponding to the electrode voltage of 32.3 kV), and breakdown occurs after about 10 s. The average amplitude of the acoustic partial discharge signals monitored by the built-in acoustic sensor during the voltage increase process is as Figure 3 shown, and the pulse frequency of the acoustic partial discharge is as Figure 4 shown. During the discharge development process, the low-frequency component of the acoustic signal increases, and the schematic diagram of the change in the time-domain and frequency-domain distributions of the acoustic signal is as Figure 5 shown.

[0083] Specifically, according to Figure 3 、 Figure 4 the analysis of the discharge test data of the full-scale transformer, the partial discharge acoustic signal shows a development law of overall increase, local decline, and sharp rise before breakdown. During the initial stage and the development stage of the discharge, the average amplitude of the partial discharge acoustic signal increases overall, the pulse frequency increases, and the amplitude change rate is small. During the severe discharge stage, the average amplitude of the partial discharge acoustic signal shows a local decline, and a stepwise upward jump occurs before breakdown, that is, the average amplitude change in the later stage of the discharge shows a "concave" shape. The overall growth amplitude of the acoustic signal of oil-paper insulation discharge is relatively large; the overall growth amplitude of the acoustic signal of oil-gap insulation discharge is relatively small.

[0084] Further, according to the test law that the average value of the amplitude of the partial discharge signal, the discharge pulse frequency, and the amplitude change rate generally show an increasing trend during the discharge development process, design a "concave curve + two out of three" partial discharge occurrence detection and confirmation logic, as Figure 6 shown.

[0085] Specifically, the amplitude start criterion is that the maximum value of the amplitude of the detected partial discharge signal is greater than the set threshold. This threshold value should be set with high sensitivity, but it should be able to avoid the amplitude of the background noise. After the amplitude is greater than the start value, start the time window and extract the characteristic values of the average amplitude, discharge pulse frequency, and amplitude change rate. Among them, when two of the three characteristic values of "average amplitude" and "amplitude change rate" exceed the limit, the "two out of three" logic is satisfied.

[0086] Specifically, the amplitude of the acoustic partial discharge signal increases overall in the middle and early stages, and the average discharge amplitude in the later stage increases after a local decline, satisfying the "concave curve" logic.

[0087] Based on Figure 5The "concave" curve + two-out-of-three warning logic determines that insulation breakdown is imminent and triggers a protection tripping action when two of the three eigenvalues have exceeded the limit or the amplitude shows the "concave" curve feature.

[0088] Embodiment 2:

[0089] The present invention also proposes an on-line monitoring and warning system 200 for converter transformer partial discharge based on fiber optic acoustic signals, as Figure 7 shown, including:

[0090] An on-line monitoring unit 201 for on-line monitoring of the target converter transformer based on fiber optic acoustic sensors and obtaining the fiber optic acoustic signals of the entire process from the start of discharge to breakdown of typical defects of the target converter transformer;

[0091] A warning unit 202 for extracting characteristic parameters from the fiber optic acoustic signals and issuing a partial discharge warning for the converter transformer based on the preset warning strategy according to the characteristic parameters.

[0092] Among them, the on-line warning system for converter transformer partial discharge further includes:

[0093] A strategy formulation unit 203 for obtaining the characteristic laws of each stage of converter transformer defect discharge and formulating a warning strategy based on the characteristic laws.

[0094] Among them, obtaining the characteristic laws of each stage of converter transformer defect discharge includes:

[0095] Setting a typical defect model inside a full-scale converter transformer model and simulating the process of typical defects of the converter transformer from the start of discharge to arc breakdown to obtain simulation test data, and obtaining the characteristic laws of each stage of converter transformer defect discharge based on the simulation test data.

[0096] Among them, the typical defect model includes at least one of the following:

[0097] Tip discharge model, floating discharge model and surface discharge model.

[0098] Among them, when simulating the process of typical defects of the converter transformer from the start of discharge to arc breakdown, the voltage boosting method adopts a combination of constant voltage boosting and step voltage boosting.

[0099] Among them, the process of typical defects from the start of discharge to arc breakdown includes:

[0100] Discharge start stage, discharge development stage and discharge severity until breakdown stage.

[0101] Among them, the characteristic laws include:

[0102] The characteristic laws of the average amplitude value, the discharge pulse frequency, and the amplitude change rate of the partial discharge signal during the discharge development process.

[0103] Among them, the early warning strategy includes: the partial discharge early warning logic;

[0104] The partial discharge early warning logic includes:

[0105] When in the later stage of discharge development, the average amplitude of the discharge signal shows the characteristic laws of overall increase, local decline, and sharp rise before breakdown, and when any two of the three characteristic parameters of the average amplitude value, the discharge pulse frequency, and the amplitude change rate exceed the limit value, a partial discharge early warning is issued.

[0106] The present invention receives the acoustic signal generated by the partial discharge inside the converter transformer through an in - built fiber - optic acoustic sensor, extracts the characteristic parameters of "average amplitude value, discharge pulse frequency, amplitude change rate" that characterize the whole process of the occurrence, development, and breakdown of different types of partial discharges. According to the "concave curve + two - out - of - three" logical judgment, it can quickly and reliably analyze the development of the fault discharge, and accurately obtain the fault discharge stage before the internal fault insulation breakdown of the converter transformer. When the early warning strategy determines that two of the three characteristic values have exceeded the limit or the amplitude shows the "concave curve" characteristic, it is determined that insulation breakdown is imminent, and a protection tripping action is carried out. The present invention gives full play to the advantages of high detection sensitivity, fast response speed, and strong anti - interference ability of the in - built acoustic sensor, and provides a basis for formulating an active defense strategy for the internal discharge of the converter transformer.

[0107] Embodiment 3:

[0108] Based on the same inventive concept, the present invention also provides a computer device, which includes a processor and a memory. The memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or may also be other general - purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field - Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, and is suitable for implementing one or more instructions. Specifically, it is suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of the method in the above - mentioned embodiment.

[0109] Embodiment 4:

[0110] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory). The computer-readable storage medium is a memory device in a computer device, used to store programs and data. It can be understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and, of course, the extended storage medium supported by the computer device. The computer-readable storage medium provides a storage space, and this storage space stores the operating system of the terminal. Moreover, one or more instructions suitable for being loaded and executed by the processor are stored in this storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. One or more instructions stored in the computer-readable storage medium can be loaded and executed by the processor to implement the steps of the method in the above embodiments.

[0111] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes. The solutions in the embodiments of the present invention can be implemented in various computer languages. For example, object-oriented programming languages such as Java and interpreted scripting languages such as JavaScript.

[0112] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to the embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the specified functions in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0113] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to work in a particular manner, such that the instructions stored in the computer-readable memory produce a manufacture including an instruction means that implements the function specified in one process or a plurality of processes and / or blocks Figure 1 in one block or a plurality of blocks Figure 1 specified in one or more processes and / or blocks.

[0114] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus, such that a series of operational steps are performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing steps for implementing the function specified in one process or a plurality of processes and / or blocks Figure 1 in one block or a plurality of blocks Figure 1 specified in one or more processes and / or blocks.

[0115] Although the preferred embodiments of the present invention have been described, additional changes and modifications can be made by those skilled in the art once they learn of the basic creative concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0116] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. An online monitoring and early warning method for partial discharge of a commutation transformer based on optical fiber acoustic signals, characterized in that: include: Performing online monitoring of a target converter transformer based on a fiber optic acoustic sensor, and obtaining a fiber optic acoustic signal of the target converter transformer from the initiation of a typical defect discharge to the breakdown; Characteristic parameters in the optical fiber acoustic signal are extracted, and based on a pre-established early warning strategy and the characteristic parameters, a partial discharge early warning of the converter transformer is issued.

2. The converter transformer partial discharge online warning method according to claim 1 is characterized in that: Develop an early warning strategy in advance, including: The characteristic laws of each stage of defective discharge of the converter transformer are obtained, and an early warning strategy is formulated based on the characteristic laws.

3. The converter transformer partial discharge online warning method according to claim 1 is characterized in that: The method of obtaining characteristic rules of each stage of defective discharge of converter transformer includes: A typical defect model is set inside the real converter transformer model, and the converter transformer and the typical defect process from initial discharge to arc breakdown are simulated to obtain simulation test data. Based on the simulation test data, the characteristic laws of each stage of converter transformer defect discharge are obtained.

4. The converter transformer partial discharge online warning method according to claim 3 is characterized in that: The typical defect model includes at least one of the following: Tip discharge model, suspension discharge model and surface discharge model.

5. The converter transformer partial discharge online warning method according to claim 3 is characterized in that: In the simulated converter transformer, when the typical defect progresses from initial discharge to arc breakdown, the voltage boosting method adopts a combination of constant voltage boosting and step voltage boosting.

6. The converter transformer partial discharge online warning method according to claim 3 is characterized in that: The typical defects from the initial discharge to the arc breakdown process include: The discharge initial stage, discharge development stage and discharge severe until breakdown stage.

7. The converter transformer partial discharge online warning method according to claim 1, characterized in that: The characteristic laws include: The characteristic laws of the average amplitude value, discharge pulse frequency and amplitude change rate of the partial discharge signal during the discharge development process.

8. The converter transformer partial discharge online warning method according to claim 1 is characterized in that: The early warning strategy includes: partial discharge early warning logic; The partial discharge warning logic includes: In the later stage of discharge development, the average amplitude of the discharge signal shows the characteristic pattern of overall rise, local decline and high surge before breakdown, and when any two of the three characteristic parameters of amplitude average value, discharge pulse frequency and amplitude change rate exceed the limit value, a partial discharge warning is issued.

9. An online monitoring and early warning system for partial discharge of commutation transformer based on optical fiber acoustic signals, characterized in that: include: An online monitoring unit, used for online monitoring of a target converter transformer based on a fiber optic acoustic sensor, and obtaining a fiber optic acoustic signal of the target converter transformer from the initiation of a typical defect discharge to the breakdown; The early warning unit is used to extract characteristic parameters from the optical fiber acoustic signal, and based on a pre-established early warning strategy and the characteristic parameters, issue a partial discharge early warning of the converter transformer.

10. The converter transformer partial discharge online warning system according to claim 9, characterized in that: The converter transformer partial discharge online warning system also includes: The strategy formulation unit is used to obtain the characteristic laws of each stage of defective discharge of the converter transformer and formulate an early warning strategy based on the characteristic laws.

11. The converter transformer partial discharge online warning system according to claim 9, characterized in that: The method of obtaining characteristic rules of each stage of defective discharge of converter transformer includes: A typical defect model is set inside the real converter transformer model, and the converter transformer and the typical defect process from initial discharge to arc breakdown are simulated to obtain simulation test data. Based on the simulation test data, the characteristic laws of each stage of converter transformer defect discharge are obtained.

12. The converter transformer partial discharge online warning system according to claim 11, characterized in that: The typical defect model includes at least one of the following: Tip discharge model, suspension discharge model and surface discharge model.

13. The converter transformer partial discharge online warning system according to claim 11, characterized in that: In the simulated converter transformer, when the typical defect progresses from initial discharge to arc breakdown, the voltage boosting method adopts a combination of constant voltage boosting and step voltage boosting.

14. The converter transformer partial discharge online warning system according to claim 11, characterized in that: The typical defects from the initial discharge to the arc breakdown process include: The discharge initial stage, discharge development stage and discharge severe until breakdown stage.

15. The converter transformer partial discharge online warning system according to claim 9, characterized in that: The characteristic laws include: The characteristic laws of the average amplitude value, discharge pulse frequency and amplitude change rate of the partial discharge signal during the discharge development process.

16. The converter transformer partial discharge online warning system according to claim 9, characterized in that: The early warning strategy includes: partial discharge early warning logic; The partial discharge warning logic includes: In the later stage of discharge development, the average amplitude of the discharge signal shows the characteristic pattern of overall rise, local decline and high surge before breakdown, and when any two of the three characteristic parameters of amplitude average value, discharge pulse frequency and amplitude change rate exceed the limit value, a partial discharge warning is issued.

17. A computer device, characterized in that: include: one or more processors; a processor for executing one or more programs; When the one or more programs are executed by the one or more processors, the method according to any one of claims 1 to 8 is implemented.

18. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed, the method according to any one of claims 1 to 8 is implemented.

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