Electric furnace transformer short network current detection and fault diagnosis method and device

Abstract

The invention discloses an electric furnace transformer short network current detection and fault diagnosis method and device. The method comprises the steps of obtaining current and serial number of each copper pipe at the head end of a low-voltage winding of an electric furnace transformer; calculating the current of each copper tile according to the current of each copper pipe and the corresponding relation between the copper pipe number and the copper tile number; the current of the copper tile is the vector sum of the current of all the copper pipes connected with the copper tile; when the difference value between the current of a certain copper pipe and the average current of the copper pipe exceeds a first set threshold value, it is judged that the copper pipe has a fault, and the number of the copper pipe is determined; and when the difference value between the current of a certain copper tile and the average current of the copper tile exceeds a second set threshold value, judging that the copper tile has a fault and determining the serial number of the copper tile. Compared with the prior art, the short network current can be detected, the fault position can be determined, and technicians can conveniently remove the fault in time. Secondly, compared with an existing differential protection device, the differential protection device is simple, reliable, excellent in economic performance and high in practicability.

Description

Technical Field

[0001] The invention relates to the technical field of smelting equipment, and in particular to a method and a device for detecting and diagnosing short-circuit current of an electric furnace transformer. Background Art

[0002] The transformer of a large metallurgical electric furnace generally adopts the main transformer + series transformer voltage regulation method. The power supply voltage on the primary side of the main transformer is generally 10kV~35kV; the secondary side is a low-voltage winding; the tertiary side is an on-load voltage regulating winding with a switching switch, and the voltage regulation gear is as many as 21 levels. The series transformer high-voltage winding is connected in series with the main transformer on-load voltage regulating winding, and the series transformer low-voltage winding is connected in series with the main transformer low-voltage winding to supply power to the furnace electrode. The voltage range is tens of volts to hundreds of volts, and the current can reach tens of thousands of amperes. The gear above the rated voltage on the low-voltage side of the electric furnace transformer is the constant power section, and the gear below the rated voltage is the constant current section. The percentage of short-circuit impedance corresponding to each gear of the electric furnace transformer gradually increases as the output voltage goes from high to low.

[0003] The output current of the low-voltage winding of the electric furnace transformer is large, and the output terminals are arranged in a staggered manner, so it is impossible to use an electromagnetic current transformer for measurement. At present, the main measurement method is to install an electromagnetic current transformer on the primary or tertiary side of the main transformer, and convert it into the output current on the low-voltage side through the gear ratio of the electric furnace transformer, or use a flexible large Rogowski coil to surround all the copper tubes connected to the head end of the low-voltage winding to directly measure the low-voltage side current, or use a small Rogowski coil to cover each copper tube connected to the head end of the low-voltage winding, and connect all the small Rogowski coils in series, and then connect them to an integrator to measure the low-voltage winding current.

[0004] However, the above method can only measure the electrode current and the low-voltage side winding current, and therefore can only detect whether there is a fault current but cannot determine the fault location, resulting in time-consuming and labor-intensive troubleshooting. Summary of the invention

[0005] The present invention provides a method and device for detecting and diagnosing short-circuit current of an electric furnace transformer, so as to solve the technical problem that the existing short-circuit fault detection method of an electric furnace transformer can only detect whether there is a fault current but cannot determine the fault location, resulting in time-consuming and laborious fault elimination.

[0006] To achieve the above object, the present invention adopts the following technical solution.

[0007] On the one hand, a method for detecting and diagnosing short-circuit current of an electric furnace transformer is provided, comprising the following steps:

[0008] Obtain the current and number of each copper tube at the head end of the low-voltage winding of the electric furnace transformer;

[0009] According to the current of each copper tube and the corresponding relationship between the copper tube number and the copper tile number, the current of each copper tile is calculated; the current of the copper tile is the vector sum of the currents of all copper tubes connected to the copper tile;

[0010] When the difference between the current of a copper tube and the average current of the copper tubes exceeds a first set threshold, it is determined that the copper tube has a fault and the number of the copper tube is determined;

[0011] When the difference between the current of a copper tile and the average current of the copper tiles exceeds a second set threshold, it is determined that the copper tile has a fault and the serial number of the copper tile is determined.

[0012] In some embodiments, the method further comprises:

[0013] According to the current of each copper tile and the corresponding relationship between the copper tile number and the electrode number, the current of each electrode is calculated; the current of an electrode is the vector sum of the currents of all copper tiles connected to the electrode;

[0014] When the difference between the current of a certain electrode and the average current of the electrode exceeds the third set threshold, the depth of the electrode inserted into the molten pool is adjusted so that the difference between the current of the electrode and the average current of the electrode does not exceed the third set threshold.

[0015] On the other hand, a short-circuit current detection and fault diagnosis device for an electric furnace transformer is provided, comprising:

[0016] Rogowski coils are installed on the copper tubes at the head end of the low-voltage winding of the electric furnace transformer;

[0017] A plurality of integrators, one end of each integrator being electrically connected to a Rogowski coil of a copper tube;

[0018] a signal conditioning module, electrically connected to the other end of the integrator, and used for filtering and amplifying the current analog signal output by the integrator; and

[0019] A current detection module, whose input terminal is electrically connected to the input terminal of the signal conditioning module, is used to:

[0020] According to the current of each copper tube and the corresponding relationship between the copper tube number and the copper tile number, the current of each copper tile is calculated; the current of the copper tile is the vector sum of the currents of all copper tubes connected to the copper tile;

[0021] When the difference between the current of a copper tube and the average current of the copper tubes exceeds a first set threshold, it is determined that the copper tube has a fault and the number of the copper tube is determined;

[0022] When the difference between the current of a copper tile and the average current of the copper tiles exceeds a second set threshold, it is determined that the copper tile has a fault and the serial number of the copper tile is determined.

[0023] In some embodiments, the current detection module is further used to:

[0024] According to the current of each copper tile and the corresponding relationship between the copper tile number and the electrode number, the current of each electrode is calculated; the current of an electrode is the vector sum of the currents of all copper tiles connected to the electrode;

[0025] When the difference between the current of a certain electrode and the average current of the electrode exceeds the third set threshold, the depth of the electrode inserted into the molten pool is adjusted so that the difference between the current of the electrode and the average current of the electrode does not exceed the third set threshold.

[0026] In some embodiments, the integrator and signal conditioning module are arranged in a first control box, and three first control boxes are provided, corresponding to the three phases of the electric furnace transformer respectively; each first control box is provided with multiple integrators and a signal conditioning module, and each integrator in each first control box is electrically connected to the Rogowski coil of each copper tube of the corresponding phase.

[0027] In some embodiments, the electric furnace transformer includes a main transformer and a series transformer; the main transformer includes a main transformer high-voltage winding, a main transformer low-voltage winding and a main transformer on-load voltage regulating winding equipped with a switching switch; the series transformer includes a series transformer high-voltage winding and a series transformer low-voltage winding; the series transformer high-voltage winding is connected in series with the main transformer on-load voltage regulating winding, and the series transformer low-voltage winding is connected in series with the main transformer low-voltage winding.

[0028] In some embodiments, a current transformer is provided on the series transformer high voltage winding, the current transformer is electrically connected to a first input terminal of a differential protection device, and the current detection module is electrically connected to a second input terminal of the differential protection device; the current detection module is used to:

[0029] The low-voltage side winding current of each phase is calculated based on the current of each copper tube; the low-voltage side winding current of each phase is the vector sum of the currents of all copper tubes of the corresponding phase;

[0030] The calculated single-phase low-voltage side winding current is transmitted to the differential protection device.

[0031] On the other hand, a computer device is provided, comprising a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above method.

[0032] On the other hand, a computer-readable storage medium is provided, on which a computer program / instruction is stored, characterized in that the computer program / instruction implements the steps of the above method when executed by a processor.

[0033] On the other hand, a computer program product is provided, comprising a computer program / instruction, characterized in that the computer program / instruction implements the steps of the above method when executed by a processor.

[0034] The present invention has at least the following technical effects or advantages:

[0035] 1. Real-time monitoring and fault location of copper tube current imbalance can be achieved by dynamically measuring the current of all copper tubes. By comparing the deviation between the operating current of each copper tube and the average current of the copper tube, when the deviation of the copper tube current exceeds the set threshold, an alarm will be issued and the number of the copper tube in abnormal or faulty state will be displayed. According to the alarm prompt, the operation and maintenance personnel will check whether all the connection joints of the alarm copper tube circuit are intact, whether the core wire of the water-cooling cable is broken, etc., and eliminate the fault in time.

[0036] 2. Real-time monitoring of copper tile current imbalance and fault location can be achieved by dynamically measuring the current of all copper tiles. By comparing the deviation between the operating current of each copper tile and the average current, when the deviation of the copper tile current exceeds the allowable threshold, an alarm will be issued and the number of the copper tile in abnormal or faulty state will be displayed. The operation and maintenance personnel will promptly deal with the loose connection between the copper tile and the electrode according to the alarm prompt to avoid the copper tile from burning out due to poor contact.

[0037] 3. By dynamically measuring the three-phase electrode current, the three-phase electrode current imbalance is automatically controlled within the allowable range to achieve safe and efficient operation of the electric furnace. By comparing the deviation between the operating current of each electrode and the average current, when the deviation of the electrode current exceeds the allowable threshold, the depth of the electrode inserted into the molten pool is automatically controlled to accurately adjust the electrode current to meet the deviation requirements.

[0038] 4. The differential protection device composed of the low-voltage winding current of the main transformer and the high-voltage winding current of the series transformer connected to the microcomputer protection device realizes the complete protection of the electric furnace transformer. Compared with the existing differential protection device that needs to collect the gear of the transformer and calculate the balance coefficient of each gear, the differential protection device of this application is simple, reliable, economical and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram of the winding connection of an electric furnace transformer in one embodiment of the present invention;

[0040] Figure 2 A schematic diagram of the circuit structure of a short-circuit current detection and fault diagnosis device for an electric furnace transformer in one embodiment of the present invention;

[0041] Figure 3a Schematic diagram of the structure of copper tubes, copper tiles and electrodes in one embodiment of the present invention (phase A);

[0042] Figure 3b Schematic diagram of the structure of copper tube, copper tile and electrode in one embodiment of the present invention (phase B);

[0043] Figure 3c Schematic diagram of the structure of copper tube, copper tile and electrode in one embodiment of the present invention (C phase);

[0044] Figure 4 Schematic diagram of circuit connection of a differential protection device in one embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0046] Embodiment 1

[0047] A method for detecting and diagnosing short-circuit current of an electric furnace transformer, comprising the following steps:

[0048] Obtain the current and number of each copper tube at the head end of the low-voltage winding of the electric furnace transformer;

[0049] According to the current of each copper tube and the corresponding relationship between the copper tube number and the copper tile number, the current of each copper tile is calculated; the current of the copper tile is the vector sum of the currents of all copper tubes connected to the copper tile;

[0050] When the difference between the current of a copper tube and the average current of the copper tubes exceeds a first set threshold, it is determined that the copper tube has a fault and the number of the copper tube is determined;

[0051] When the difference between the current of a copper tile and the average current of the copper tiles exceeds a second set threshold, it is determined that the copper tile has a fault and the serial number of the copper tile is determined.

[0052] Furthermore, the above method also includes:

[0053] According to the current of each copper tile and the corresponding relationship between the copper tile number and the electrode number, the current of each electrode is calculated; the current of an electrode is the vector sum of the currents of all copper tiles connected to the electrode;

[0054] When the difference between the current of a certain electrode and the average current of the electrode exceeds the third set threshold, the depth of the electrode inserted into the molten pool is adjusted so that the difference between the current of the electrode and the average current of the electrode does not exceed the third set threshold.

[0055] Embodiment 2

[0056] A short-circuit current detection and fault diagnosis device for electric furnace transformers, used for Figure 1 The electric furnace transformer shown.

[0057] like Figure 1 As shown, the electric furnace transformer includes a main transformer and a series transformer; the primary side of the main transformer is the main transformer high-voltage winding, the power supply voltage is generally 10kV ~ 35kV, the secondary side is the main transformer low-voltage winding, and the tertiary side is the main transformer on-load voltage regulating winding equipped with a switch. The series transformer includes a series transformer high-voltage winding and a series transformer low-voltage winding; the series transformer high-voltage winding is connected in series with the main transformer on-load voltage regulating winding, and the series transformer low-voltage winding is connected in series with the main transformer low-voltage winding.

[0058] like Figure 2 As shown, the short-circuit current detection and fault diagnosis device for the electric furnace transformer includes:

[0059] Rogowski coil 1, installed on each copper tube 21 at the head end of the low-voltage winding of the electric furnace transformer;

[0060] A plurality of integrators 3, one end of each integrator 3 is electrically connected to a Rogowski coil 1 of a copper tube 21;

[0061] A signal conditioning module 4 is electrically connected to the other end of the integrator 3 and is used to filter and amplify the current analog signal output by the integrator 3; and

[0062] The current detection module 5, whose input end is electrically connected to the output end of the signal conditioning module 4, is used to:

[0063] The current of each copper tile 22 is calculated according to the current of each copper tube 21 and the correspondence between the copper tube number and the copper tile number; the current of the copper tile 22 is the vector sum of the currents of all copper tubes 21 connected to the copper tile 22.

[0064] When the difference between the current of a copper tube 21 and the average current of the copper tubes exceeds a first set threshold, it is determined that the copper tube 21 has a fault and the number of the copper tube is determined.

[0065] When the difference between the current of a copper tile 22 and the average current of the copper tiles exceeds the second set threshold, it is determined that the copper tile 22 has a fault and the serial number of the copper tile 22 is determined.

[0066] The output signal of the Rogowski coil is the induced electromotive force generated by the alternating current in the conductor being measured. The induced electromotive force is in a differential relationship with the current in the conductor being measured. The integrator obtains the current value of the conductor being measured by integrating the induced electromotive force. The output end of the integrator is connected to the signal conditioning module, which filters and amplifies the current analog signal output by the integrator. After the current detection module performs logical operations, the copper tube current, copper tile current, electrode current and low-voltage side winding current can be monitored in real time.

[0067] Furthermore, the current detection module 5 is also used for:

[0068] The current of each electrode 23 is calculated according to the current of each copper tile 22 and the corresponding relationship between the copper tile number and the electrode number; the current of the electrode 23 is the vector sum of the currents of all copper tiles 22 connected to the electrode 23;

[0069] When the difference between the current of a certain electrode 23 and the average current of the electrode exceeds the third set threshold, the depth of the electrode 23 inserted into the molten pool is adjusted so that the difference between the current of the electrode 23 and the average current of the electrode does not exceed the third set threshold. It should be noted that the device for adjusting the depth of each electrode 23 inserted into the molten pool is a prior art and does not fall within the scope of improvement of the present application.

[0070] Preferably, if Figure 2 As shown, the integrator 3 and the signal conditioning module 4 are arranged in the first control box 61, and the first control box 61 is provided with three, respectively corresponding to the three phases A, B, and C of the electric furnace transformer; each first control box is provided with eight integrators 3 and a signal conditioning module 4, and each integrator 3 in each first control box 61 is electrically connected to the Rogowski coil 1 of each copper tube 21 of the corresponding phase. The current detection module 5 is arranged in the second control box 62, and the current detection module 5 has four interfaces, namely the first interface 51, the second interface 52, the third interface 53 and the fourth interface 54. The first interface 51 is an RS485 Ethernet interface, which outputs the short-circuit copper tube current, copper tile current, electrode current and three-phase low-voltage side winding current digital signals. The second interface 52 is a 4-20mA analog signal interface, which outputs the three-phase low-voltage side winding analog current signal. The third interface 53 is a GPS or Beidou standard timing signal interface to achieve time synchronization with the substation. The fourth interface 54 is a USB2.0 debugging interface. The Rogowski coil 1 is electrically connected to the integrator 3 through a signal output shielded cable, and the signal conditioning module 4 is electrically connected to the current detection module 5 through a signal output shielded cable.

[0071] Figure 3a-3c The structures of copper tubes, copper tiles and electrodes of the three phases A, B and C of the electric furnace transformer are shown respectively. a1~a8, x1~x8 are eight pairs of staggered terminal outlets of the low voltage winding of the phase A of the electric furnace transformer, a is the beginning of the winding, and x is the end of the winding. b1~b8, y1~y8 are eight pairs of staggered terminal outlets of the low voltage winding of the phase B of the electric furnace transformer, b is the beginning of the winding, and y is the end of the winding; c1~c8, z1~z8 are eight pairs of staggered terminal outlets of the low voltage winding of the phase C of the electric furnace transformer, c is the beginning of the winding, and z is the end of the winding. See Appendix Figure 2 A total of 24 Rogowski coils 1 are installed on all the first-end outgoing copper tubes a1~a8, b1~b8, c1~c8 of the three-phase low-voltage windings of the electric furnace transformer A, B, and C.

[0072] Preferably, if Figure 1 and Figure 4 As shown, a current transformer 7 (three-phase) is provided on the series transformer high-voltage winding of the electric furnace transformer, the current transformer 7 is electrically connected to a first input end of a differential protection device 8, and the current detection module 5 is electrically connected to a second input end of the differential protection device 8;

[0073] The current detection module 5 is also used for:

[0074] The low-voltage side winding current of each phase is calculated based on the current of each copper tube; the low-voltage side winding current of each phase is the vector sum of the currents of all copper tubes of the corresponding phase;

[0075] The calculated single-phase low-voltage side winding current is transmitted to the differential protection device 8.

[0076] The differential protection device 8 adopts a microcomputer protection device, the first input end adopts a 5A or 1A CT input current interface, and the second input end adopts a 4-20mA analog signal input interface. The current transformer 7 is connected to the first input end of the differential protection device 8 through a shielded control cable, and the second interface 52 of the current detection module 5 is connected to the second input end of the differential protection device 8 using a twisted pair. The high-voltage side of the series transformer is Y-connected, and the low-voltage side is connected to the electrode in a △ connection. The high- and low-voltage side currents connected to the differential protection device 8 are both winding currents, and the differential protection device 8 does not need phase angle compensation. The high and low voltage windings of the series transformer have a fixed transformation ratio. It is only necessary to calculate the balance coefficient according to the secondary rated currents of the high and low voltage sides to adjust the amplitude of the differential protection device.

[0077] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0078] Similarly, it should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this disclosed method should not be interpreted as reflecting the intention that the claimed invention requires more features than those expressly recited in each claim. Rather, as reflected in the claims, inventive aspects lie in less than all of the features of the individual embodiments previously disclosed. Therefore, the claims that follow the detailed description are hereby expressly incorporated into the detailed description, with each claim itself serving as a separate embodiment of the present invention.

[0079] Those skilled in the art will appreciate that the modules or units or groups of the devices in the examples disclosed herein may be arranged in the device as described in the embodiment, or alternatively may be located in one or more devices different from the devices in the example. The modules in the foregoing examples may be combined into one module or may be divided into multiple submodules.

[0080] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or groups in the embodiments may be combined into one module or unit or group, and in addition they may be divided into a plurality of submodules or subunits or subgroups. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0081] Furthermore, those skilled in the art will appreciate that although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features from different embodiments is meant to be within the scope of the present invention and to form different embodiments.

[0082] In addition, some of the embodiments are described herein as methods or combinations of method elements that can be implemented by a processor of a computer system or by other devices that perform the functions. Therefore, a processor with necessary instructions for implementing the method or method elements forms a device for implementing the method or method elements. In addition, the elements described herein of the device embodiments are examples of devices for implementing the functions performed by the elements for the purpose of implementing the invention.

[0083] The various techniques described herein may be implemented in combination with hardware or software, or a combination thereof. Thus, the method and apparatus of the present invention, or some aspects or portions of the method and apparatus of the present invention may be in the form of program codes (i.e., instructions) embedded in a tangible medium, such as a floppy disk, a CD-ROM, a hard disk drive, or any other machine-readable storage medium, wherein when the program is loaded into a machine such as a computer and executed by the machine, the machine becomes a device for practicing the present invention.

[0084] In the case where the program code is executed on a programmable computer, the computing device generally includes a processor, a storage medium readable by the processor (including volatile and non-volatile memory and / or storage elements), at least one input device, and at least one output device. The memory is configured to store the program code; the processor is configured to execute the method of the present invention according to the instructions in the program code stored in the memory.

[0085] By way of example and not limitation, computer readable media include computer storage media and communication media. Computer readable media include computer storage media and communication media. Computer storage media stores information such as computer readable instructions, data structures, program modules or other data. Communication media generally embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transmission mechanism, and includes any information delivery medium. Any combination of the above is also included within the scope of computer readable media.

[0086] As used herein, unless otherwise specified, the use of ordinal numbers "first," "second," "third," etc. to describe common objects merely indicates that different instances of similar objects are involved, and is not intended to imply that the objects so described must have a given order in time, space, order, or in any other manner.

[0087] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments may be envisioned within the scope of the invention thus described. In addition, it should be noted that the language used in this specification is selected primarily for readability and teaching purposes, rather than for explaining or defining the subject matter of the present invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the present invention is illustrative, not restrictive, with respect to the scope of the present invention, which is defined by the appended claims.

[0088] Finally, it should be noted that the present invention does not explain in detail the common knowledge recognized by technicians in this field. The above is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for detecting and diagnosing short-circuit current of an electric furnace transformer, characterized in that: The method comprises the following steps: Obtain the current and number of each copper tube at the head end of the low-voltage winding of the electric furnace transformer; According to the current of each copper tube and the corresponding relationship between the copper tube number and the copper tile number, the current of each copper tile is calculated; the current of the copper tile is the vector sum of the currents of all copper tubes connected to the copper tile; When the difference between the current of a copper tube and the average current of the copper tubes exceeds a first set threshold, it is determined that the copper tube has a fault and the number of the copper tube is determined; When the difference between the current of a copper tile and the average current of the copper tiles exceeds a second set threshold, it is determined that the copper tile has a fault and the serial number of the copper tile is determined.

2. The method for detecting and diagnosing short-circuit current of an electric furnace transformer according to claim 1, characterized in that: The method further comprises: According to the current of each copper tile and the corresponding relationship between the copper tile number and the electrode number, the current of each electrode is calculated; the current of an electrode is the vector sum of the currents of all copper tiles connected to the electrode; When the difference between the current of a certain electrode and the average current of the electrode exceeds the third set threshold, the depth of the electrode inserted into the molten pool is adjusted so that the difference between the current of the electrode and the average current of the electrode does not exceed the third set threshold.

3. A short-circuit current detection and fault diagnosis device for an electric furnace transformer, characterized in that: include: Rogowski coils are installed on the copper tubes at the head end of the low-voltage winding of the electric furnace transformer; A plurality of integrators, one end of each integrator being electrically connected to a Rogowski coil of a copper tube; A signal conditioning module, electrically connected to the other end of the integrator, and used for filtering and amplifying the current analog signal output by the integrator; and A current detection module, whose input end is electrically connected to the output end of the signal conditioning module, is used to: According to the current of each copper tube and the corresponding relationship between the copper tube number and the copper tile number, the current of each copper tile is calculated; the current of the copper tile is the vector sum of the currents of all copper tubes connected to the copper tile; According to the current of each copper tile and the corresponding relationship between the copper tile number and the electrode number, the current of each electrode is calculated; the current of an electrode is the vector sum of the currents of all copper tiles connected to the electrode; When the difference between the current of the copper tube and the average current of the copper tube exceeds a first set threshold, it is determined that the corresponding copper tube has a fault and the number of the copper tube is determined; When the difference between the current of the copper tile and the average current of the copper tiles exceeds a second set threshold, it is determined that the corresponding copper tile has a fault and the serial number of the copper tile is determined; When the difference between the electrode current and the electrode average current exceeds the third set threshold, an instruction is sent to the execution unit to adjust the depth of the electrode inserted into the molten pool so that the difference between the electrode current and the electrode average current does not exceed the third set threshold.

4. The short-circuit current detection and fault diagnosis device for electric furnace transformer according to claim 3 is characterized in that: The current detection module is also used for: According to the current of each copper tile and the corresponding relationship between the copper tile number and the electrode number, the current of each electrode is calculated; the current of an electrode is the vector sum of the currents of all copper tiles connected to the electrode; When the difference between the current of a certain electrode and the average current of the electrode exceeds the third set threshold, the depth of the electrode inserted into the molten pool is adjusted so that the difference between the current of the electrode and the average current of the electrode does not exceed the third set threshold.

5. The short-circuit current detection and fault diagnosis device for an electric furnace transformer according to claim 3 or 4, characterized in that: The integrator and signal conditioning module are arranged in the first control box. There are three first control boxes, which correspond to the three phases of the electric furnace transformer respectively. Each first control box is equipped with multiple integrators and a signal conditioning module. Each integrator in each first control box is electrically connected to each copper tube of the corresponding phase.

6. The short-circuit current detection and fault diagnosis device for an electric furnace transformer according to claim 3 or 4, characterized in that: The electric furnace transformer includes a main transformer and a series transformer; the main transformer includes a main transformer high-voltage winding, a main transformer low-voltage winding and a main transformer on-load voltage regulating winding equipped with a switching switch; the series transformer includes a series transformer high-voltage winding and a series transformer low-voltage winding; the series transformer high-voltage winding is connected in series with the main transformer on-load voltage regulating winding, and the series transformer low-voltage winding is connected in series with the main transformer low-voltage winding.

7. The short-circuit current detection and fault diagnosis device for an electric furnace transformer according to claim 6, characterized in that: The series transformer high-voltage winding is provided with a current transformer, the current transformer is electrically connected to a first input terminal of a differential protection device, and the current detection module is electrically connected to a second input terminal of the differential protection device; The current detection module is used for: The low-voltage side winding current of each phase is calculated based on the current of each copper tube; the low-voltage side winding current of each phase is the vector sum of the currents of all copper tubes of the corresponding phase; The calculated single-phase low-voltage side winding current is transmitted to the differential protection device.

8. A computer device comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to claim 1 or 2.

9. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the steps of the method according to claim 1 or 2 are implemented.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method according to claim 1 or 2 are implemented.

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