Converter transformer visual partial discharge monitoring simulation test platform

Abstract

The invention provides a visual partial discharge monitoring simulation test platform for a converter transformer. The visual partial discharge monitoring simulation test platform comprises a real test transformer, a sensing unit, a partial discharge defect model structure, a visual monitoring unit and a data processing unit, the partial discharge defect model structure is connected with related parts of the real-type test transformer to form a test high-voltage loop; a sensing unit is arranged on the real-model test transformer and is used for acquiring a partial discharge signal of the real-model test transformer; the visual monitoring unit is arranged in the real transformer and is used for acquiring image and video data in the process from internal defect discharge to breakdown of the real transformer; the data processing unit is connected with the sensing unit and is used for processing the partial discharge signal to obtain a characteristic spectrum of the partial discharge characteristic quantity; and the data processing unit is also used for performing accurate correspondence on the characteristic spectrum of the partial discharge characteristic quantity and the image and video data on a time axis so as to realize visual simulation monitoring of the discharge data of the real-type test transformer.

Description

Technical Field

[0001] The present invention relates to the technical field of online monitoring of electric power equipment, and in particular to a visualized partial discharge monitoring simulation test platform for a converter transformer. Background Art

[0002] The converter transformer is one of the important power equipment in the power transmission system and is the hub of power transmission. Its own reliable operation is extremely critical to the stable operation of the power grid system. After the internal discharge of the converter transformer occurs, it will quickly develop into arcing, causing more serious safety accidents. Therefore, timely detection of the internal discharge of the converter transformer is of great significance for timely warning and avoiding serious accidents such as transformer explosion.

[0003] Whether it is the traditional current, ultra-high frequency sensor, or the new fiber optic sensor, although great progress has been made in the performance of detection sensitivity, detection frequency band, etc. in the laboratory environment, the effectiveness of the sensing performance under the operating conditions of the real transformer lacks experimental verification, and the fusion installation method with the real transformer lacks implementation experience. The data detected on site is usually a single sensing method, lacking data from multi-sensor joint synchronous detection, and before the transformer is dismantled, it is usually impossible to accurately judge the defect type from the field data, making it difficult to diagnose and identify partial discharge. In addition, there are few samples of partial discharge data on site, which makes it difficult to improve the accuracy of the constructed diagnostic algorithm model. Since it is difficult to obtain test data suitable for the field, the existing experimental research based on the transformer partial discharge simulation platform uses mostly simplified transformer models, ignoring the structure of the transformer, or scaling down the actual transformer in proportion, which cannot accurately reflect the propagation characteristics of the partial discharge signal inside the transformer. Summary of the invention

[0004] In view of this, the present invention proposes a visualized partial discharge monitoring simulation test platform for converter transformers, aiming to solve the technical problems in the prior art that field data of converter transformers is difficult to obtain and simulation data is difficult to reflect the actual discharge characteristics. The present invention proposes a converter transformer visualized partial discharge monitoring simulation test platform, comprising: a real test transformer, a sensor unit, a partial discharge defect model structure, a visualized monitoring unit and a data processing unit; wherein, The partial discharge defect model structure is built into the oil tank of the real test transformer and connected to relevant components of the real test transformer to form a test high voltage circuit; The real test transformer is provided with a sensor unit for obtaining a partial discharge signal of the real test transformer; The visual monitoring unit is built into the real transformer and is used to collect images and video data of the process from internal defect discharge to breakdown of the real transformer; The data processing unit is connected to the sensor unit to receive the partial discharge signal acquired by the sensor unit and obtain a characteristic spectrum of the partial discharge characteristic quantity after processing the partial discharge signal; The data processing unit is also connected to the visual monitoring unit to receive the image and video data collected by the visual monitoring unit, and accurately correspond the characteristic map of the partial discharge characteristic quantity with the image and video data on the time axis, thereby realizing visual simulation monitoring of the discharge data of the real test transformer.

[0005] Furthermore, in the above-mentioned converter transformer visualized partial discharge monitoring simulation test platform, the partial discharge defect model structure is a suspended discharge structure, a tip discharge structure or a surface discharge structure.

[0006] Furthermore, in the above converter transformer visualized partial discharge monitoring simulation test platform, the suspended discharge structure comprises: a first shell and a first flat ground electrode, a flat suspended electrode and a first flat high-voltage electrode disposed therein; wherein, The flat plate-shaped suspension electrode is adjustably connected to the first flat plate-shaped ground electrode and a preset distance is maintained between the two; The first planar high voltage electrode and the planar suspension electrode are arranged opposite to each other, and the distance between the two is adjustable.

[0007] Furthermore, in the above-mentioned converter transformer visualized partial discharge monitoring simulation test platform, a tungsten needle is arranged on the planar floating electrode, and the tip of the tungsten needle is arranged toward the first planar high-voltage electrode; and the distance between the tungsten needle and the first planar ground electrode is adjustable.

[0008] Furthermore, in the above converter transformer visualized partial discharge monitoring simulation test platform, the tip discharge structure comprises: a second shell and a second flat plate-shaped ground electrode and a needle tip electrode disposed inside the second shell; wherein, A first insulating paperboard is arranged between the second flat plate-shaped ground electrode and the needle tip electrode, and the distance between the second flat plate-shaped ground electrode and the needle tip electrode is adjustable.

[0009] Furthermore, in the above converter transformer visualized partial discharge monitoring simulation test platform, the surface discharge structure includes: a third shell and a cylindrical high-voltage electrode and a third flat ground electrode placed inside the third shell; wherein, A second insulating paperboard is arranged between the cylindrical high-voltage electrode and the third flat-plate ground electrode.

[0010] Furthermore, in the above converter transformer visualized partial discharge monitoring simulation test platform, the sensing unit includes: a first ultra-high frequency partial discharge sensor, an ultrasonic sensor, a second ultra-high frequency sensor and a high frequency partial discharge current sensor; wherein, The first ultra-high frequency partial discharge sensor is built into the true test transformer; the second ultra-high frequency partial discharge sensor and the ultrasonic sensor are both arranged on the outer casing of the true test transformer; the high frequency partial discharge current sensor is connected to the test high-voltage circuit formed after the partial discharge defect model structure is connected to the true test transformer.

[0011] Furthermore, in the above-mentioned converter transformer visualized partial discharge monitoring simulation test platform, there are three first ultra-high frequency partial discharge sensors, six ultrasonic sensors, one second ultra-high frequency sensor, and one high-frequency partial discharge current sensor.

[0012] Furthermore, in the above-mentioned converter transformer visualized partial discharge monitoring simulation test platform, the high-voltage electrode of the partial discharge defect model structure is connected to the winding lead-out terminal of the real test transformer, and the ground electrode of the partial discharge defect model structure is connected to the casing of the real test transformer.

[0013] Furthermore, in the above converter transformer visualized partial discharge monitoring simulation test platform, the visualized monitoring unit comprises: an endoscope; wherein, The endoscope is connected to the true-type test transformer via a docking device with external threads.

[0014] The converter transformer visualized partial discharge monitoring simulation test platform of the present invention performs a discharge test by embedding a partial discharge defect model structure inside a real test transformer, using a visualization unit to observe image data of the entire discharge process from the start of discharge to breakdown of the defect, obtaining discharge characteristic data of different types of defects inside the transformer oil tank through a sensor unit and mastering the discharge characteristic data of typical defects inside the oil tank, receiving the discharge data collected by the sensor unit through a data processing unit, and synchronizing the image and video data collected by the visualization monitoring unit, thereby providing data support for improving the accuracy and efficiency of the defect type diagnosis model. At the same time, there is no need to pump out or change oil when replacing the partial discharge defect model structure, thereby simplifying the operation process and improving the test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings: Figure 1A schematic diagram of the structure of a converter transformer visualized partial discharge monitoring simulation test platform provided by an embodiment of the present invention; Figure 2 A top view of a partial discharge defect model of a converter transformer provided in an embodiment of the present invention; Figure 3 A schematic structural diagram of a suspended discharge structure in a partial discharge defect model structure provided by an embodiment of the present invention; Figure 4 A schematic structural diagram of a tip discharge structure in a partial discharge defect model structure provided by an embodiment of the present invention; Figure 5 A schematic structural diagram of a surface discharge structure in a partial discharge defect model structure provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0016] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0017] See also Figure 1 and Figure 2 The converter transformer visualized partial discharge monitoring simulation test platform of the embodiment of the present invention comprises: a real test transformer 1, a sensor unit (not shown in the figure), a partial discharge defect model structure 2, a visualized monitoring unit 3 and a data processing unit (not shown in the figure); wherein the partial discharge defect model structure 2 is built in the oil tank of the real test transformer 1 and is connected to the relevant components of the real test transformer 1 to form a test high-voltage circuit; the real test transformer 1 is provided with a sensor unit for obtaining the partial discharge signal of the real test transformer 1; the visualized monitoring unit 3 is built in the real transformer for The data processing unit is connected to the sensor unit to receive the local discharge signal obtained by the sensor unit, and obtains the characteristic spectrum of the local discharge characteristic quantity after processing the local discharge signal; the data processing unit is also connected to the visual monitoring unit 3 to receive the image and video data collected by the visual monitoring unit 3, and accurately corresponds the characteristic spectrum of the local discharge characteristic quantity with the image and video data on the time axis, so as to realize the visual simulation monitoring of the discharge data of the real test transformer 1.

[0018] Specifically, the real test transformer 1 is a single-phase transformer, for example, it can be a single-phase transformer modified from a three-phase double-winding transformer.

[0019] In this embodiment, the partial discharge signal includes ultrasonic, high frequency, ultra-high frequency signal, etc. The high voltage electrode of the partial discharge defect model structure 2 is in contact with the electrode led out of the winding 11, and the ground electrode of the partial discharge defect model structure 2 is connected to the ground through the equipotential bonding wire of the transformer casing to form a test high voltage circuit.

[0020] In specific implementation, the partial discharge defect model structure 2 is placed inside the transformer from the top of the real test transformer 1. The high voltage electrode of the partial discharge defect model structure 2 is connected to the lead-out end of the winding 11 of the real test transformer 1, and the ground electrode of the partial discharge defect model structure 2 is grounded through the connecting rod 13.

[0021] More specifically, the high-voltage electrode of the partial discharge defect model structure 2 is connected to the electrode of the winding lead-out end of the true test transformer 1 through the high-voltage lead 12, and the ground electrode of the partial discharge defect model structure 2 is connected to the ground through the equipotential bonding wire of the casing of the true test transformer 1.

[0022] In this embodiment, the partial discharge defect model structure 2 is a suspended discharge structure 21, a tip discharge structure 22 or a surface discharge structure 23. By setting various types of defect structure models, the discharge condition inside the real test transformer 1 can be simulated more accurately.

[0023] In this embodiment, the sensing unit includes: a first ultra-high frequency partial discharge sensor, an ultrasonic sensor, a second ultra-high frequency sensor and a high-frequency partial discharge current sensor; wherein, the first ultra-high frequency partial discharge sensor is built into the true test transformer 1; the second ultra-high frequency partial discharge sensor and the ultrasonic sensor are both arranged on the outer casing of the true test transformer 1; the high-frequency partial discharge current sensor is connected to the test high-voltage circuit formed after the partial discharge defect model structure 2 is connected to the true test transformer 1.

[0024] During specific implementation, the second UHF sensor is fixed to the transformer housing through a hand hole, the ultrasonic sensor is attached to the outer wall of the transformer through an ultrasonic coupling agent, and the high-frequency partial discharge current sensor is connected through a test loop.

[0025] More specifically, in this embodiment, there are three first ultra-high frequency partial discharge sensors, six ultrasonic sensors, one second ultra-high frequency sensor, and one high-frequency partial discharge current sensor. The ultra-high frequency sensor, ultrasonic sensor, and high-frequency current sensor can receive electromagnetic waves, ultrasonic waves, and current signals generated by internal discharge of the transformer. When multiple sensors monitor simultaneously, the positioning function can be realized according to the time difference of the incoming wave signals.

[0026] Correspondingly, the data processing unit can have multiple signal acquisition channels, can simultaneously monitor ultrasonic, high-frequency, and ultra-high-frequency signals, support B code timing function, can simultaneously monitor the perception data transmitted by ultrasonic, high-frequency, and ultra-high-frequency signal sensor units, extract the maximum amplitude of the signal, discharge frequency, phase distribution and other information, and support the analysis of the frequency domain distribution, pulse width, pulse integral and other information of the pulse signal.

[0027] For example, the data processing unit has at least 12 signal acquisition channels, which can collect data from the above-mentioned three first ultra-high frequency partial discharge sensors, six ultrasonic sensors, one second ultra-high frequency sensor and one high-frequency partial discharge current sensor, and a spare acquisition channel is reserved (for example, during system maintenance or calibration, the spare channel can be used to continue collecting data, so that necessary adjustments or repairs can be made to the main channel without affecting normal operations).

[0028] The data processing unit has a data analysis module. By using the data analysis module to dynamically call various types of collected data through the measurement and control software, the trend curve of characteristic quantities such as partial discharge, signal amplitude, and discharge frequency can be realized, and characteristic graphs can be displayed and data can be exported. In other words, the data processing unit collects data and forms a characteristic graph with coordinate axes, phase, frequency, and amplitude based on the collected data, which is conducive to mastering the discharge characteristic data of typical defects inside the transformer tank.

[0029] In this embodiment, the visual monitoring unit 3 includes: an endoscope 31; wherein the endoscope 31 is connected to the true-type test transformer 1 through a docking device with external threads.

[0030] During the specific implementation, a mounting hole is opened at the corresponding position of the shell of the real test transformer 1, and a docking device with an external thread is set in the mounting hole to cooperate with the internal thread connector of the endoscope to ensure that the two are tightly combined to form a sealed interface to prevent transformer oil leakage. One end of the hose is connected to the endoscope body, and the other end is connected to the internal thread connector. A ball valve docking flange is welded on the outside of the mounting hole. This flange is used to connect the control valve to close the channel when the endoscope is not in use, further enhancing safety. At the same time, an insulating bracket is set inside the transformer to fix the endoscope. A hand hole is opened on one side of the mounting hole to facilitate the operator to install the endoscope and subsequent maintenance work.

[0031] An endoscope mounting hole is welded on the short axis surface of the true test transformer 1, and an external threaded metal docking device is welded on the inner side of the mounting hole to connect with the endoscope mounting device to ensure oil-proof sealing; a ball valve docking flange is welded on the outer side of the mounting hole, and a DN200 reserved hand hole is welded near the endoscope mounting hole for endoscope installation, and an insulating bracket is set inside the transformer to fix the endoscope.

[0032] The endoscope can realize high-speed video recording and can capture partial discharge phenomena inside the transformer, such as arcs, sparks or glowing points. The endoscope can also continuously record the video of the process from internal defect discharge to breakdown of the real transformer, so as to conduct time series analysis and observe the development trend of partial discharge of the real test transformer 1.

[0033] Finally, the transformer state quantity and partial discharge process data monitored by the data processing unit are synchronously matched with the video image data collected in real time by the visualization monitoring unit 3, providing strong data support for improving the accuracy and efficiency of the defect type diagnosis model.

[0034] In this embodiment, a time synchronization module can also be included to ensure the time synchronization between the visual monitoring unit 3 and the data processing unit, so that the two can perform data synchronization and correspondence according to the same time reference, so as to synchronously obtain images of typical discharge defects and the process of development to breakdown, as well as acoustic, electrical and other multi-parameter characteristics, thereby providing data support for timely discovery of internal defects of the converter transformer.

[0035] During the test, the high-voltage test power supply is connected between the real test transformer 1 and the partial discharge defect model structure 2 to ensure that the power supply can provide the required voltage level; the discharge current, voltage waveform, phase information, etc. are monitored and recorded by the data processing unit; the visual monitoring unit 3 is turned on to start capturing the image and video data inside the real test transformer 1; after the test starts, the test is first started at a lower voltage, and the voltage is gradually increased until it reaches a predetermined value. When the voltage rises enough to trigger partial discharge, the discharge phenomenon is recorded, and the data processing unit is used to collect partial discharge process data, and the visual monitoring unit 3 is used to capture the visual discharge process, and then the data obtained by the two are synchronized. In this embodiment, three partial discharge defect model structures 2 can be used for testing respectively, and the differences between three different types of partial discharge defects can be compared, which is beneficial to improve the diagnosis accuracy and efficiency of transformer defect types.

[0036] It can be obviously concluded from the above that the converter transformer visualized partial discharge monitoring simulation test platform provided in this embodiment performs a discharge test by embedding the partial discharge defect model structure into a real test transformer, and uses a visualization unit to observe the image data of the entire discharge process from the beginning of discharge to breakdown of the defect, obtains the discharge characteristic data of different types of defects inside the transformer oil tank through the sensor unit and masters the discharge characteristic data of typical defects inside the oil tank, receives the discharge data collected by the sensor unit through the data processing unit, and synchronizes it with the image and video data collected by the visualization monitoring unit, so as to provide data support for improving the accuracy and diagnostic efficiency of the defect type diagnosis model. At the same time, there is no need to pump out or change oil when replacing the discharge model, which simplifies the operation process and improves the test efficiency.

[0037] See also Figure 3 In the above embodiment, the suspended discharge structure 21 includes: a first shell 211 and a first flat-plate ground electrode 212, a flat-plate suspension electrode 213 and a first flat-plate high-voltage electrode 214 disposed therein; wherein the flat-plate suspension electrode 213 is connected to the first flat-plate ground electrode 212 in an adjustable manner and a preset distance is maintained between the two; the first flat-plate high-voltage electrode 214 is arranged opposite to the flat-plate suspension electrode 213 and the distance between the two is adjustable.

[0038] Specifically, the first shell 211 is a cylindrical structure, the first flat plate-shaped ground electrode 212 may include an electrode rod and a copper disc-shaped structure connected to each other, and the flat plate-shaped suspension electrode 213 may be an aluminum disc-shaped structure. The first flat plate-shaped high-voltage electrode 214 may include an electrode rod and a disc-shaped structure. The diameters of the first flat plate-shaped ground electrode 212, the flat plate-shaped suspension electrode 213 and the first flat plate-shaped high-voltage electrode 214 may be consistent, for example, all 60 mm. The flat plate-shaped suspension electrode 213 may be connected to the first flat plate-shaped ground electrode in a threaded manner through a nylon connector 215, and the vertical spacing between the two may be 5 mm. After the flat plate-shaped suspension electrode 213 is connected to the first flat plate-shaped ground electrode 212 as a whole, the distance between it and the first flat plate-shaped high-voltage electrode 214 can be adjusted.

[0039] Furthermore, in order to make the suspended discharge structure 21 easier to discharge, a tungsten needle (not shown in the figure) is arranged on the planar suspended electrode 213, and the tip of the tungsten needle is arranged toward the first planar high-voltage electrode 214; and the distance between the tungsten needle and the first planar ground electrode 212 is adjustable.

[0040] In a specific implementation, a threaded hole is opened on the aluminum suspension electrode 213, and a round tungsten needle fixing structure is installed in the form of a thread. By screwing the tungsten needle, the distance between the tungsten needle and the ground electrode can be adjusted.

[0041] See also Figure 4In the above embodiment, the tip discharge structure 22 includes: a second shell 221 and a second flat-plate ground electrode 222 and a needle-tip electrode 223 placed inside the second shell 221; wherein a first insulating paperboard 224 is arranged between the second flat-plate ground electrode 222 and the needle-tip electrode 223, and the distance between the second flat-plate ground electrode 222 and the needle-tip electrode 223 is adjustable.

[0042] Specifically, the second housing 221 is a cylindrical structure. The second flat plate-shaped ground electrode 222 may include an electrode rod and a disc-shaped structure connected to each other, the electrode rod may have a diameter of 2 cm, the disc may have a diameter of 60 mm, and the thickness may be 5 mm. The needle tip electrode 223 may be composed of a needle rod and a needle tip, the needle rod diameter may be 1 cm, and the needle tip diameter may be 0.1-0.2 mm. The vertical distance between the needle tip and the second flat plate-shaped ground electrode 222 is adjustable, for example, the maximum distance between the two is 6 cm.

[0043] Furthermore, to prevent oil gap breakdown, a first insulating paperboard 224 is provided between the second flat ground electrode 222 and the needle tip electrode 223, and the thickness thereof may be 3 mm. The first insulating paperboard 224 may be an oil-paper insulating paperboard, and may be glued between the second flat ground electrode 222 and the needle tip electrode 223. The needle plate discharge is an extremely non-uniform electric field discharge, which can maintain a stable corona discharge in the oil, and the discharge amount is about 100 pC.

[0044] See also Figure 5 In the above embodiment, the surface discharge structure 23 includes: a third shell 231 and a cylindrical high-voltage electrode 232 and a third flat-plate ground electrode 233 disposed therein; wherein a second insulating paperboard 234 is disposed between the cylindrical high-voltage electrode 232 and the third flat-plate ground electrode 233.

[0045] Specifically, the third shell 231 may be cylindrical. The third flat plate-shaped ground electrode 233 may include connected electrode rods and a disc-shaped structure, for example, the disc may have a diameter of 60 mm and a thickness of 5 mm; the electrode rod may have a diameter of 2 cm. The cylindrical high-voltage electrode 232 may include connected electrode rods and a columnar portion, and the diameter of the columnar portion may be 25 mm. The corners of the columnar portion are arc transition surfaces. The thickness of the second insulating paperboard 234 may be 3 mm, and the second insulating paperboard 234 may be glued between the cylindrical high-voltage electrode 232 and the third flat plate-shaped ground electrode 233.

[0046] Furthermore, the surface discharge can form a discharge with a large amplitude variation range, with a discharge amount of 100pC~10000pC.

[0047] In summary, the present invention can simulate the typical partial discharge characteristics of three types of transformers, namely suspended discharge, tip discharge and surface discharge in transformer oil, and can obtain image and video data of the development process of typical defect discharge through the built-in visual monitoring unit. The data acquisition and analysis system synchronously collects electrical and acoustic data of the discharge initiation, development and breakdown process, solving the problem that field data is difficult to obtain and simulation data is difficult to reflect the real discharge characteristics, and provides data support for improving the accuracy and diagnostic efficiency of the defect type diagnosis model.

[0048] 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 equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A converter transformer visualized partial discharge monitoring simulation test platform, characterized in that: include: True-type test transformer, sensor unit, partial discharge defect model structure, visual monitoring unit and data processing unit; among them, The partial discharge defect model structure is built into the oil tank of the real test transformer and connected to relevant components of the real test transformer to form a test high voltage circuit; The real test transformer is provided with a sensor unit for obtaining a partial discharge signal of the real test transformer; The visual monitoring unit is built into the real transformer and is used to collect images and video data of the process from internal defect discharge to breakdown of the real transformer; The data processing unit is connected to the sensor unit to receive the partial discharge signal acquired by the sensor unit and obtain a characteristic spectrum of the partial discharge characteristic quantity after processing the partial discharge signal; The data processing unit is also connected to the visual monitoring unit to receive the image and video data collected by the visual monitoring unit, and accurately correspond the characteristic map of the partial discharge characteristic quantity with the image and video data on the time axis, thereby realizing visual simulation monitoring of the discharge data of the real test transformer.

2. The converter transformer visualized partial discharge monitoring simulation test platform according to claim 1 is characterized in that: The local discharge defect model structure is a suspended discharge structure, a tip discharge structure or a surface discharge structure.

3. The converter transformer visualized partial discharge monitoring simulation test platform according to claim 2 is characterized in that: The suspension discharge structure comprises: a first shell and a first flat ground electrode, a flat suspension electrode and a first flat high voltage electrode placed inside the shell; wherein, The flat plate-shaped suspension electrode is adjustably connected to the first flat plate-shaped ground electrode and a preset distance is maintained between the two; The first planar high voltage electrode and the planar suspension electrode are arranged opposite to each other, and the distance between the two is adjustable.

4. The converter transformer visualized partial discharge monitoring simulation test platform according to claim 3 is characterized in that: A tungsten needle is arranged on the planar floating electrode, and the tip of the tungsten needle is arranged toward the first planar high-voltage electrode; and the distance between the tungsten needle and the first planar ground electrode is adjustable.

5. The converter transformer visualized partial discharge monitoring simulation test platform according to claim 2 is characterized in that: The tip discharge structure comprises: a second shell and a second flat plate-shaped ground electrode and a needle tip electrode placed inside the second shell; wherein, A first insulating paperboard is arranged between the second flat plate-shaped ground electrode and the needle tip electrode, and the distance between the second flat plate-shaped ground electrode and the needle tip electrode is adjustable.

6. The converter transformer visualized partial discharge monitoring simulation test platform according to claim 2 is characterized in that: The surface discharge structure comprises: a third shell and a cylindrical high-voltage electrode and a third flat-plate ground electrode placed inside the third shell; wherein, A second insulating paperboard is arranged between the cylindrical high-voltage electrode and the third flat-plate ground electrode.

7. The converter transformer visualized partial discharge monitoring simulation test platform according to claim 1 is characterized in that: The sensing unit includes: a first ultra-high frequency partial discharge sensor, an ultrasonic sensor, a second ultra-high frequency sensor and a high frequency partial discharge current sensor; wherein, The first ultra-high frequency partial discharge sensor is built into the true test transformer; the second ultra-high frequency partial discharge sensor and the ultrasonic sensor are both arranged on the outer casing of the true test transformer; the high frequency partial discharge current sensor is connected to the test high-voltage circuit formed after the partial discharge defect model structure is connected to the true test transformer.

8. The converter transformer visualized partial discharge monitoring simulation test platform according to claim 7 is characterized in that: There are three first ultra-high frequency partial discharge sensors, six ultrasonic sensors, one second ultra-high frequency sensor, and one high-frequency partial discharge current sensor.

9. The converter transformer visualized partial discharge monitoring simulation test platform according to claim 1 is characterized in that: The high voltage electrode of the partial discharge defect model structure is connected to the winding lead-out end of the true test transformer, and the ground electrode of the partial discharge defect model structure is connected to the shell of the true test transformer.

10. The converter transformer visualized partial discharge monitoring simulation test platform according to claim 1 is characterized in that: The visual monitoring unit comprises: an endoscope; wherein, The endoscope is connected to the true-type test transformer via a docking device with external threads.

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