A transformer operation state evaluation method and device based on short-circuit impact

Abstract

This invention discloses a method and apparatus for evaluating the operating status of a transformer based on short-circuit impact. The method involves real-time monitoring of the bus circuit breaker currents on all three sides of the transformer using a fault recording device in a substation. When a tripping event is detected in the transformer, the peak short-circuit current values ​​on all three sides of the transformer are collected. These three sides include the high-voltage side, the medium-voltage side, and the low-voltage side. Based on these peak short-circuit current values, short-circuit current impact coefficients are calculated for each side. Then, based on these impact coefficients, the transformer's short-circuit withstand capability loss after the short-circuit impact is calculated. These loss values ​​are accumulated to obtain the total short-circuit withstand capability loss value, leading to the transformer's operating status evaluation result and corresponding maintenance strategy. This approach ensures reliable transformer operation and allows for early detection of potential risks.

Description

Technical Field

[0001] This invention relates to the technical field of transformers, and in particular to a method and apparatus for evaluating the operating status of transformers based on short-circuit impact. Background Technology

[0002] Power transformers are important equipment in the power grid, and their stable and reliable operation plays a vital role in the safety of the power grid.

[0003] Insufficient short-circuit withstand capability is a major type of transformer fault, with most cases resulting from repeated short-circuit impacts. Current methods for assessing transformers subjected to multiple short-circuit impacts include simulation, full-scale transformer testing, and material testing; however, there are few dedicated computational models to calculate this problem and provide different handling strategies. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method and device for evaluating the operating status of a transformer based on short-circuit impact, which evaluates the operating status of the transformer in real time according to the short-circuit impact situation of the transformer and pushes operation and maintenance strategies, thereby improving the reliability of transformer operation.

[0005] To address the aforementioned technical problems, this invention provides a method for evaluating the operating status of a transformer based on short-circuit impact, comprising:

[0006] Determine whether the substation has a fault recording device. If so, monitor the bus circuit breaker current on the three sides of the transformer in the fault recording device in real time. When a tripping situation is detected in the transformer, collect the peak value of the short-circuit current on the three sides of the transformer in the fault recording device. The three sides of the transformer include the high-voltage side, the medium-voltage side and the low-voltage side of the transformer.

[0007] Based on the peak short-circuit current on the three sides of the transformer, calculate the short-circuit current impact coefficients corresponding to the three sides of the transformer.

[0008] Based on the short-circuit current impact coefficient, the short-circuit withstand capability loss value of the transformer after the short-circuit impact is calculated. The short-circuit withstand capability loss value is accumulated to obtain the total short-circuit withstand capability loss value. Based on this total short-circuit withstand capability loss value, the transformer's operating status assessment result and corresponding operation and maintenance strategy are obtained.

[0009] In one possible implementation, the short-circuit current impact coefficients for the three sides of the transformer are calculated based on the peak short-circuit currents on each side, specifically including:

[0010] The maximum allowable short-circuit current peak value corresponding to the three windings of the transformer is obtained respectively, wherein the three windings of the transformer include the high-voltage side winding, the medium-voltage side winding, and the low-voltage side winding.

[0011] Calculate the ratio of the peak short-circuit current on each of the three sides of the transformer to the maximum allowable peak short-circuit current corresponding to the three windings of the transformer, and use the ratio as the short-circuit current impact coefficient corresponding to the three sides of the transformer.

[0012] In one possible implementation, after determining whether the substation has a fault recording device, the method further includes:

[0013] If the substation does not have a fault recording device, then the effective values ​​of the circuit currents on the three sides of the transformer obtained by the protection device in the substation are read.

[0014] Based on the grid voltage level corresponding to the transformer, a preset short-circuit current peak coefficient is selected. According to the effective value of the circuit current and the preset short-circuit current peak coefficient, the peak value of the short-circuit current on the three sides of the transformer is obtained.

[0015] In one possible implementation, a preset short-circuit current peak coefficient is selected based on the grid voltage level corresponding to the transformer, specifically including:

[0016] Obtain the grid voltage level corresponding to the transformer. When the grid voltage level is 110kV, the preset short-circuit current peak factor is 2.55. When the grid voltage level is greater than or equal to 220kV, the preset short-circuit current peak factor is 2.69.

[0017] In one possible implementation, the loss of the transformer's short-circuit withstand capability after a short-circuit impact is calculated based on the short-circuit current impact coefficient, specifically including:

[0018] Obtain the service life coefficient of the transformer and the number of short-circuit impacts that the transformer suffers from consecutive short-circuit impacts within a preset time.

[0019] Substitute the operating life coefficient, the number of short-circuit impacts, and the short-circuit current impact coefficients corresponding to the three sides of the transformer into the preset formula for calculating the short-circuit withstand capability loss value, and calculate and obtain the short-circuit withstand capability loss value of the transformer after the short-circuit impact.

[0020] The formula for calculating the preset short-circuit withstand capability loss value is as follows:

[0021] LOSS = A·T·e max(CH,CM,CL)·N ;

[0022] In the formula, A is a constant, taken as 1.67, T is the transformer service life coefficient, N is the number of short-circuit impacts, CH is the short-circuit current impact coefficient on the high-voltage side of the transformer, CM is the short-circuit current impact coefficient on the medium-voltage side of the transformer, and CL is the short-circuit current impact coefficient on the low-voltage side of the transformer.

[0023] In one possible implementation, obtaining the service life coefficient of the transformer specifically includes:

[0024] The transformer's service life is obtained, and based on the pre-defined service life levels, the service life level corresponding to the current service life is determined. Based on the service life level, the corresponding service life coefficient is matched.

[0025] In one possible implementation, based on the total short-circuit withstand capability loss value, the transformer's operating status assessment result and corresponding operation and maintenance strategy are obtained, specifically including:

[0026] Based on the pre-defined total short-circuit capability loss value levels, determine the total short-circuit capability loss value level corresponding to the current total short-circuit capability loss value.

[0027] Based on the total short-circuit withstand capability loss level, the corresponding transformer operation status assessment results and its operation and maintenance strategies are matched.

[0028] The present invention also provides a transformer operating status assessment device based on short-circuit impact, comprising: a short-circuit current peak value acquisition module, a short-circuit current impact coefficient acquisition module, and an operating status assessment module;

[0029] The short-circuit current peak acquisition module is used to determine whether the substation has a fault recording device. If so, it monitors the bus circuit breaker current on the three sides of the transformer in the fault recording device in real time. When a tripping situation is detected in the transformer, it collects the short-circuit current peak value on the three sides of the transformer in the fault recording device. The three sides of the transformer include the high-voltage side, the medium-voltage side, and the low-voltage side of the transformer.

[0030] The short-circuit current impact coefficient acquisition module is used to calculate the short-circuit current impact coefficients corresponding to the three sides of the transformer based on the peak values ​​of the short-circuit currents on the three sides of the transformer.

[0031] The operation status assessment module is used to calculate the short-circuit withstand capability loss value of the transformer after a short-circuit impact based on the short-circuit current impact coefficient, accumulate the short-circuit withstand capability loss value, and obtain the operation status assessment result of the transformer and the corresponding operation and maintenance strategy based on the total short-circuit withstand capability loss value.

[0032] In one possible implementation, the short-circuit current impact coefficient acquisition module is used to calculate the short-circuit current impact coefficients corresponding to the three sides of the transformer based on the peak values ​​of the short-circuit currents on the three sides of the transformer, specifically including:

[0033] The maximum allowable short-circuit current peak value corresponding to the three windings of the transformer is obtained respectively, wherein the three windings of the transformer include the high-voltage side winding, the medium-voltage side winding, and the low-voltage side winding.

[0034] Calculate the ratio of the peak short-circuit current on each of the three sides of the transformer to the maximum allowable peak short-circuit current corresponding to the three windings of the transformer, and use the ratio as the short-circuit current impact coefficient corresponding to the three sides of the transformer.

[0035] In one possible implementation, the short-circuit current peak acquisition module, after determining whether the substation has a fault recording device, is further used for:

[0036] If the substation does not have a fault recording device, then the effective values ​​of the circuit currents on the three sides of the transformer obtained by the protection device in the substation are read.

[0037] Based on the grid voltage level corresponding to the transformer, a preset short-circuit current peak coefficient is selected. According to the effective value of the circuit current and the preset short-circuit current peak coefficient, the peak value of the short-circuit current on the three sides of the transformer is obtained.

[0038] In one possible implementation, the short-circuit current peak value acquisition module is used to select a preset short-circuit current peak value coefficient based on the grid voltage level corresponding to the transformer, specifically including:

[0039] Obtain the grid voltage level corresponding to the transformer. When the grid voltage level is 110kV, the preset short-circuit current peak factor is 2.55. When the grid voltage level is greater than or equal to 220kV, the preset short-circuit current peak factor is 2.69.

[0040] In one possible implementation, the operating status assessment module is used to calculate the short-circuit withstand capability loss value of the transformer after a short-circuit impact based on the short-circuit current impact coefficient, specifically including:

[0041] Obtain the service life coefficient of the transformer and the number of short-circuit impacts that the transformer suffers from consecutive short-circuit impacts within a preset time.

[0042] Substitute the operating life coefficient, the number of short-circuit impacts, and the short-circuit current impact coefficients corresponding to the three sides of the transformer into the preset formula for calculating the short-circuit withstand capability loss value, and calculate and obtain the short-circuit withstand capability loss value of the transformer after the short-circuit impact.

[0043] The formula for calculating the preset short-circuit withstand capability loss value is as follows:

[0044] LOSS = A·T·e max(CH,CM,CL)·N ;

[0045] In the formula, A is a constant, taken as 1.67, T is the transformer service life coefficient, N is the number of short-circuit impacts, CH is the short-circuit current impact coefficient on the high-voltage side of the transformer, CM is the short-circuit current impact coefficient on the medium-voltage side of the transformer, and CL is the short-circuit current impact coefficient on the low-voltage side of the transformer.

[0046] In one possible implementation, the operating status assessment module is used to obtain the operating life coefficient of the transformer, specifically including:

[0047] The transformer's service life is obtained, and based on the pre-defined service life levels, the service life level corresponding to the current service life is determined. Based on the service life level, the corresponding service life coefficient is matched.

[0048] In one possible implementation, the operating status assessment module is used to obtain, and based on the total short-circuit withstand capability loss value, the operating status assessment result of the transformer and the corresponding operation and maintenance strategy, specifically including:

[0049] Based on the pre-defined total short-circuit capability loss value levels, determine the total short-circuit capability loss value level corresponding to the current total short-circuit capability loss value.

[0050] Based on the total short-circuit withstand capability loss level, the corresponding transformer operation status assessment results and its operation and maintenance strategies are matched.

[0051] The present invention also provides a terminal device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor executes the computer program to implement the transformer operating status assessment method based on short-circuit impact as described in any of the preceding claims.

[0052] The present invention also provides a computer-readable storage medium comprising a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to perform the transformer operating status assessment method based on short-circuit impact as described in any of the preceding claims.

[0053] This invention provides a method and apparatus for evaluating the operating status of a transformer based on short-circuit impact, which has the following advantages compared with the prior art:

[0054] The fault recording device monitors the bus circuit breaker currents on all three sides of the transformer in real time. When a tripping situation is detected in the transformer, the peak value of the short-circuit current on all three sides of the transformer is collected. The three sides of the transformer include the high-voltage side, the medium-voltage side, and the low-voltage side. Based on the peak value of the short-circuit current on each side, the short-circuit current impact coefficient is calculated. Based on the short-circuit current impact coefficient, the short-circuit withstand capability loss value after the short-circuit impact is calculated. The short-circuit withstand capability loss values ​​are accumulated to obtain the total short-circuit withstand capability loss value. Based on this total loss value, the transformer's operating status assessment result and corresponding operation and maintenance strategy are obtained. This invention can assess the transformer's operating status in real time based on the short-circuit impact situation and push operation and maintenance strategies, ensuring reliable transformer operation and early detection of potential risks. Attached Figure Description

[0055] Figure 1 This is a flowchart illustrating an embodiment of a transformer operating status assessment method based on short-circuit impact provided by the present invention.

[0056] Figure 2 This is a schematic diagram of an embodiment of a transformer operation status assessment device based on short-circuit impact provided by the present invention. Detailed Implementation

[0057] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0058] Example 1

[0059] See Figure 1 , Figure 1 This is a flowchart illustrating an embodiment of a transformer operating status assessment method based on short-circuit impact provided by the present invention. Figure 1 As shown, the method includes steps 101-104, as detailed below:

[0060] Step 101: Determine whether the substation has a fault recording device. If so, monitor the bus circuit breaker current on the three sides of the transformer in the fault recording device in real time. When a tripping situation is detected in the transformer, collect the peak value of the short-circuit current on the three sides of the transformer in the fault recording device. The three sides of the transformer include the high-voltage side, the medium-voltage side, and the low-voltage side.

[0061] In one embodiment, when the substation is equipped with a fault recording device, the bus circuit breaker currents on the three sides of the transformer are monitored in real time in the fault recording device. Specifically, the bus circuit breaker currents on the high-voltage side, the medium-voltage side, and the low-voltage side of the transformer are monitored in real time in the fault recording device.

[0062] In one embodiment, since the resistance value is close to 0 during a short circuit, theoretically the current will reach infinity. Therefore, by monitoring the bus circuit breaker currents on the three sides of the transformer in the fault recording device in real time, the tripping of the line or the transformer on each side can be detected in real time based on the changes in the bus circuit breaker currents on the three sides of the transformer.

[0063] In one embodiment, when a tripping event occurs in the transformer, the peak values ​​of the short-circuit currents on all three sides of the transformer are collected by the fault recording device. These peak values ​​include the peak value of the short-circuit current on the high-voltage side of the transformer. Ht Peak current I in the short-circuit circuit on the medium-voltage side of the transformer Mt and the peak current I of the short-circuit circuit on the low-voltage side of the transformer Lt .

[0064] In one embodiment, when the substation does not have a fault recording device, the effective values ​​of the circuit currents corresponding to the three sides of the transformer obtained by the protection device in the substation are read; wherein, the effective values ​​of the circuit currents corresponding to the three sides of the transformer include the effective values ​​of the circuit currents corresponding to the high-voltage side of the transformer, the effective values ​​of the circuit currents corresponding to the medium-voltage side of the transformer, and the effective values ​​of the circuit currents corresponding to the low-voltage side of the transformer.

[0065] In one embodiment, a preset short-circuit current peak coefficient is selected based on the grid voltage level corresponding to the transformer. Specifically, the grid voltage level corresponding to the transformer is obtained. When the grid voltage level is 110kV, the preset short-circuit current peak coefficient is 2.55. When the grid voltage level is greater than or equal to 220kV, the preset short-circuit current peak coefficient is 2.69.

[0066] In one embodiment, the peak value of the short-circuit current on the three sides of the transformer is obtained based on the effective value of the circuit current and the preset peak value coefficient of the short-circuit current. Specifically, the effective value of the circuit current on each of the three sides of the transformer is multiplied by the preset peak value coefficient of the short-circuit current to obtain the peak value of the short-circuit current on the three sides of the transformer.

[0067] Step 102: Calculate the short-circuit current impact coefficients corresponding to the three sides of the transformer based on the peak short-circuit current on the three sides of the transformer.

[0068] In one embodiment, the maximum permissible short-circuit current peak values ​​corresponding to the three windings of the transformer are obtained respectively, wherein the maximum permissible short-circuit current peak values ​​corresponding to the three windings of the transformer include the maximum permissible short-circuit current peak value I corresponding to the high-voltage side winding of the transformer. H The maximum permissible short-circuit current peak value I corresponding to the medium-voltage side winding of the transformer M The maximum permissible short-circuit current peak value I corresponding to the low-voltage side winding of the transformer L .

[0069] Preferably, since the calculation of the maximum allowable short-circuit current is relatively complex and involves many influencing operating conditions, it can be calculated according to the method of the national standard GBT13499-2007 "Guidelines for the Application of Power Transformers" for ease of practical operation.

[0070] In one embodiment, the ratio of the peak value of the short-circuit current on the three sides of the transformer to the maximum allowable peak value of the short-circuit current corresponding to the three windings of the transformer is calculated, and the ratio is used as the short-circuit current impact coefficient corresponding to the three sides of the transformer.

[0071] Specifically, the short-circuit current impact coefficients corresponding to the three sides of the transformer include the short-circuit current impact coefficient C corresponding to the high-voltage side of the transformer. H The short-circuit current impact factor C corresponding to the medium-voltage side of the transformer. M The short-circuit current impact factor C corresponding to the low-voltage side of the transformer L .

[0072] Among them, the short-circuit current impact factor C corresponding to the high-voltage side of the transformer H By calculating the peak short-circuit current I on the high-voltage side of the transformer Ht The maximum permissible short-circuit current peak value I corresponding to the high-voltage side winding of the transformer H The ratio is calculated using the following formula:

[0073] C H =I Ht / I H .

[0074] Among them, the short-circuit current impact factor C corresponding to the medium voltage side of the transformer M By calculating the peak short-circuit current I on the medium-voltage side of the transformer Mt The maximum permissible short-circuit current peak value I corresponding to the medium-voltage side winding of the transformer M The ratio is calculated using the following formula:

[0075] C M =I Mt / I M .

[0076] Among them, the short-circuit current impact factor C corresponding to the low voltage of the transformer LBy calculating the peak short-circuit current I on the low-voltage side of the transformer Lt The maximum permissible short-circuit current peak value I corresponding to the low-voltage side winding of the transformer L The ratio is calculated using the following formula:

[0077] C L =I Lt / I L .

[0078] Step 103: Based on the short-circuit current impact coefficient, calculate the short-circuit withstand capability loss value of the transformer after the short-circuit impact, accumulate the short-circuit withstand capability loss value, and obtain the transformer operation status assessment result and corresponding operation and maintenance strategy based on the total short-circuit withstand capability loss value.

[0079] In one embodiment, the loss value of the transformer's short-circuit withstand capability after a short-circuit impact is calculated based on the short-circuit current impact coefficient. Specifically, the service life coefficient of the transformer and the number of short-circuit impacts that the transformer suffers from consecutive short-circuit impacts within a preset time are obtained. The service life coefficient, the number of short-circuit impacts, and the short-circuit current impact coefficients corresponding to the three sides of the transformer are substituted into the preset formula for calculating the loss value of the transformer's short-circuit withstand capability, and the loss value of the transformer's short-circuit withstand capability after a short-circuit impact, Loss, is calculated and obtained.

[0080] The formula for calculating the preset short-circuit withstand capability loss value is as follows:

[0081] Loss=A·T·e max(CH,CM,CL)·N ;

[0082] In the formula, A is a constant, taken as 1.67, T is the transformer service life coefficient, N is the number of short-circuit impacts, CH is the short-circuit current impact coefficient on the high-voltage side of the transformer, CM is the short-circuit current impact coefficient on the medium-voltage side of the transformer, and CL is the short-circuit current impact coefficient on the low-voltage side of the transformer.

[0083] Preferably, the number of short-circuit impacts that the transformer experiences within a preset time period is obtained by a waveform recorder within the substation; the preset time period is five minutes.

[0084] In one embodiment, the operating life coefficient of the transformer is obtained. Specifically, the operating life of the transformer is obtained, the operating life level corresponding to the current operating life is determined based on the pre-divided operating life levels, and the corresponding operating life coefficient is matched based on the operating life level.

[0085] Preferably, the pre-defined operating life levels include: Level 1 operating life, Level 2 operating life, Level 3 operating life, Level 4 operating life, Level 5 operating life, and Level 6 operating life.

[0086] The operating life is as follows: Level 1: When the transformer's operating life is ≤ 5 years, T = 5; Level 2: When 5 < the transformer's operating life is ≤ 10 years, T = 10; Level 3: When 10 < the transformer's operating life is ≤ 15 years, T = 15; Level 4: When 15 < the transformer's operating life is ≤ 20 years, T = 20; Level 5: When 20 < the transformer's operating life is ≤ 25 years, T = 25; Level 6: When the transformer's operating life is > 25 years, T = 30.

[0087] In one embodiment, the short-circuit withstand capability loss values ​​are accumulated to obtain a total short-circuit withstand capability loss value, wherein the accumulation calculation formula is as follows:

[0088] TotalLoss = ∑Loss.

[0089] Preferably, the cumulative processing of the short-circuit withstand capability loss value refers to the cumulative processing of the short-circuit withstand capability loss value obtained over all time periods since the transformer was put into operation.

[0090] In one embodiment, based on the pre-defined total short-circuit capability loss value levels, the total short-circuit capability loss value level corresponding to the current total short-circuit capability loss value is determined, and the corresponding transformer operation status assessment result is matched.

[0091] Preferably, the pre-defined total short-circuit withstand capability loss levels are a first total short-circuit withstand capability loss level, a second total short-circuit withstand capability loss level, a third total short-circuit withstand capability loss level, and a fourth total short-circuit withstand capability loss level.

[0092] Specifically, when TotalLoss≥180, the total short-circuit capability loss level corresponding to the current total short-circuit capability loss value is determined as the first total short-circuit capability loss level. The transformer operation status assessment result and its operation and maintenance strategy indicate that the transformer operation status is serious, meaning that the transformer must be shut down for inspection as soon as possible. The inspection contents include: transformer oil chromatography test, winding deformation frequency response test, low voltage short-circuit impedance test, transformer core lifting inspection, return to factory for reinforcement, etc.

[0093] Specifically, when TotalLoss≥60, the total short-circuit capability loss level corresponding to the current total short-circuit capability loss value is determined as the second total short-circuit capability loss level. The transformer operation status assessment result and its operation and maintenance strategy are matched to determine the transformer operation status. Note that the transformer must be shut down for inspection as soon as possible. The inspection contents include: transformer oil chromatography test, winding deformation frequency response test, low voltage short-circuit impedance test, etc.

[0094] Specifically, when TotalLoss≥30, the total short-circuit capability loss level corresponding to the current total short-circuit capability loss value is determined to be the third total short-circuit capability loss level. The transformer operation status assessment results and its operation and maintenance strategy are matched to determine that the transformer operation status is abnormal, indicating that the tracking should be strengthened and at least two transformer oil chromatography tests should be carried out within one week.

[0095] Specifically, when TotalLoss < 30, the total short-circuit capability loss level corresponding to the current total short-circuit capability loss value is determined to be the fourth total short-circuit capability loss level. The transformer operation status assessment result and its operation and maintenance strategy are matched to determine that the transformer operation status is normal, indicating that the short-circuit impact is acceptable and the transformer can operate safely.

[0096] Example 2

[0097] See Figure 2 , Figure 2 This is a schematic diagram of an embodiment of a transformer operating status assessment device based on short-circuit impact provided by the present invention, as shown below. Figure 2 As shown, the device includes a short-circuit current peak acquisition module 201, a short-circuit current impact coefficient acquisition module 202, and an operating status evaluation module 203, as detailed below:

[0098] The short-circuit current peak acquisition module 201 is used to determine whether there is a fault recording device in the substation. If so, it monitors the bus circuit breaker current on the three sides of the transformer in the fault recording device in real time. When a tripping situation is detected in the transformer, it collects the short-circuit current peak value on the three sides of the transformer in the fault recording device. The three sides of the transformer include the high-voltage side, the medium-voltage side and the low-voltage side of the transformer.

[0099] The short-circuit current impact coefficient acquisition module 202 is used to calculate the short-circuit current impact coefficients corresponding to the three sides of the transformer based on the peak values ​​of the short-circuit currents on the three sides of the transformer.

[0100] The operation status assessment module 203 is used to calculate the short-circuit withstand capability loss value of the transformer after a short-circuit impact based on the short-circuit current impact coefficient, accumulate the short-circuit withstand capability loss value, and obtain the operation status assessment result of the transformer and the corresponding operation and maintenance strategy based on the total short-circuit withstand capability loss value.

[0101] In one embodiment, the short-circuit current impact coefficient acquisition module 202 is used to calculate the short-circuit current impact coefficients corresponding to the three sides of the transformer based on the peak values ​​of the short-circuit currents on the three sides of the transformer. Specifically, this includes: acquiring the maximum permissible peak value of the short-circuit current corresponding to the three windings of the transformer, wherein the three windings of the transformer include the high-voltage side winding, the medium-voltage side winding, and the low-voltage side winding; calculating the ratio of the peak value of the short-circuit current on the three sides of the transformer to the maximum permissible peak value of the short-circuit current corresponding to the three windings of the transformer, and using the ratio as the short-circuit current impact coefficients corresponding to the three sides of the transformer.

[0102] In one embodiment, the short-circuit current peak acquisition module 201 is used to determine whether the substation has a fault recording device, and is further used to: if the substation does not have a fault recording device, read the effective values ​​of the circuit currents corresponding to the three sides of the transformer obtained by the protection device in the substation; select a preset short-circuit current peak coefficient based on the grid voltage level corresponding to the transformer, and obtain the peak value of the short-circuit current on the three sides of the transformer according to the effective value of the circuit current and the preset short-circuit current peak coefficient.

[0103] In one embodiment, the short-circuit current peak acquisition module 201 is used to select a preset short-circuit current peak coefficient based on the grid voltage level corresponding to the transformer. Specifically, it includes: acquiring the grid voltage level corresponding to the transformer; when the grid voltage level is 110kV, the preset short-circuit current peak coefficient is 2.55; when the grid voltage level is greater than or equal to 220kV, the preset short-circuit current peak coefficient is 2.69.

[0104] In one embodiment, the operating status evaluation module 203 is used to calculate the short-circuit withstand capability loss value of the transformer after a short-circuit impact based on the short-circuit current impact coefficient. Specifically, this includes: obtaining the transformer's service life coefficient and the number of short-circuit impacts the transformer experiences consecutively within a preset time period; substituting the service life coefficient, the number of short-circuit impacts, and the corresponding short-circuit current impact coefficients on the three sides of the transformer into a preset short-circuit withstand capability loss value calculation formula to calculate and obtain the short-circuit withstand capability loss value of the transformer after a short-circuit impact; wherein, the preset short-circuit withstand capability loss value calculation formula is as follows:

[0105] LOSS = A·T·e max(CH,CM,CL)·N ;

[0106] In the formula, A is a constant, taken as 1.67, T is the transformer service life coefficient, N is the number of short-circuit impacts, CH is the short-circuit current impact coefficient on the high-voltage side of the transformer, CM is the short-circuit current impact coefficient on the medium-voltage side of the transformer, and CL is the short-circuit current impact coefficient on the low-voltage side of the transformer.

[0107] In one embodiment, the operating status assessment module 203 is used to obtain the operating life coefficient of the transformer, specifically including: obtaining the operating life of the transformer, determining the operating life level corresponding to the current operating life based on the pre-divided operating life levels, and matching the corresponding operating life coefficient based on the operating life level.

[0108] In one embodiment, the operation status assessment module 203 is used to obtain and, based on the total short-circuit withstand capability loss value, obtain the transformer operation status assessment result and the corresponding operation and maintenance strategy. Specifically, it includes: determining the total short-circuit withstand capability loss value level corresponding to the current total short-circuit withstand capability loss value based on the pre-divided total short-circuit withstand capability loss value level; and matching the corresponding transformer operation status assessment result and its operation and maintenance strategy based on the total short-circuit withstand capability loss value level.

[0109] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0110] It should be noted that the above-described embodiment of the transformer operating status assessment device based on short-circuit impact is merely illustrative. The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0111] Based on the above-described embodiments of the transformer operating status assessment method based on short-circuit impact, another embodiment of the present invention provides a transformer operating status assessment terminal device based on short-circuit impact. The transformer operating status assessment terminal device based on short-circuit impact includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the transformer operating status assessment method based on short-circuit impact according to any embodiment of the present invention.

[0112] For example, in this embodiment, the computer program can be divided into one or more modules, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules can be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of the computer program in the short-circuit impact-based transformer operating status assessment terminal device.

[0113] The transformer operation status assessment terminal device based on short-circuit impact can be a desktop computer, laptop, handheld computer, or cloud server, etc. The transformer operation status assessment terminal device based on short-circuit impact may include, but is not limited to, a processor and memory.

[0114] The processor can be a Central Processing Unit (CPU), or 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. The general-purpose processor can be a microprocessor or any conventional processor. This processor is the control center of the transformer operating status assessment terminal equipment based on short-circuit impact, connecting all parts of the terminal equipment via various interfaces and lines.

[0115] The memory can be used to store the computer programs and / or modules. The processor, by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory, realizes various functions of the transformer operation status assessment terminal device based on short-circuit impact. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function, etc.; the data storage area may store data created based on the use of the mobile phone, etc. In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0116] Based on the above embodiments of the transformer operating status assessment method based on short-circuit impact, another embodiment of the present invention provides a storage medium, the storage medium including a stored computer program, wherein, when the computer program is running, the device where the storage medium is located controls the execution of the transformer operating status assessment method based on short-circuit impact of any embodiment of the present invention.

[0117] In this embodiment, the storage medium is a computer-readable storage medium, and the computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable medium can include any entity or device capable of carrying the computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0118] In summary, this invention provides a method and apparatus for assessing the operating status of a transformer based on short-circuit impact. It uses a fault recording device in a substation to monitor the bus circuit breaker currents on all three sides of the transformer in real time. When a tripping event is detected in the transformer, the peak short-circuit current values ​​on all three sides of the transformer are collected. These three sides include the high-voltage side, the medium-voltage side, and the low-voltage side. Based on the peak short-circuit current values, the corresponding short-circuit current impact coefficients are calculated for each side. Based on these impact coefficients, the short-circuit withstand capability loss after the short-circuit impact is calculated. These loss values ​​are then accumulated to obtain the total short-circuit withstand capability loss value. Based on this total loss value, the transformer's operating status assessment result and corresponding maintenance strategy are obtained, ensuring reliable transformer operation and early detection of potential risks.

[0119] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A method for evaluating the operating state of a transformer based on a short-circuit impulse, characterized in that The method comprises the following steps: determining whether a fault recording device is present in a substation, if so, real-time monitoring of the circuit breaker current of the bus on the three sides of the transformer in the fault recording device, when a trip condition is detected in the transformer, collecting the short-circuit current peak value of the three sides of the transformer in the fault recording device, wherein the three sides of the transformer include the high-voltage side of the transformer, the medium-voltage side of the transformer and the low-voltage side of the transformer; According to the short-circuit current peak value of the three sides of the transformer, the short-circuit current impact coefficient corresponding to the three sides of the transformer is calculated respectively; According to the short-circuit current impact coefficient, the anti-short-circuit capability loss value of the transformer after short-circuit impact is calculated, the anti-short-circuit capability loss value is accumulated, and the total anti-short-circuit capability loss value is obtained, and the operation state evaluation result of the transformer and the corresponding operation and maintenance strategy are obtained; Wherein, according to the short-circuit current impact coefficient, the anti-short-circuit capability loss value of the transformer after short-circuit impact is calculated, specifically including: obtaining the operation life coefficient of the transformer and the short-circuit impact frequency of the transformer continuously suffering short-circuit impact within a predetermined time; The operation life coefficient, the short-circuit impact frequency and the short-circuit current impact coefficient corresponding to the three sides of the transformer are substituted into the preset anti-short-circuit capability loss value calculation formula to calculate and obtain the anti-short-circuit capability loss value of the transformer after short-circuit impact; Wherein, the preset anti-short-circuit capability loss value calculation formula is as follows: LOSS = A - T - e max(CH,CM,CL)·N ; In the formula, A is a constant, taking 1.67, T is the operation life coefficient of the transformer, N is the short-circuit impact frequency, CH is the short-circuit current impact coefficient of the high-voltage side of the transformer, CM is the short-circuit current impact coefficient of the medium-voltage side of the transformer, and CL is the short-circuit current impact coefficient of the low-voltage side of the transformer.

2. The transformer operating state evaluation method based on short-circuit impulse according to claim 1, characterized in that, According to the short-circuit current peak value of the three sides of the transformer, the short-circuit current impact coefficient corresponding to the three sides of the transformer is calculated respectively, specifically including: The maximum allowable short-circuit current peak value corresponding to the three sides of the transformer winding is obtained respectively, wherein the three sides of the transformer winding include the high-voltage side winding of the transformer, the medium-voltage side winding of the transformer and the low-voltage side winding of the transformer; The ratio of the short-circuit current peak value of the three sides of the transformer to the maximum allowable short-circuit current peak value corresponding to the three sides of the transformer winding is calculated respectively, and the ratio is taken as the short-circuit current impact coefficient corresponding to the three sides of the transformer.

3. The transformer operating state evaluation method based on short-circuit impulse according to claim 1, characterized in that, After determining whether a fault recording device is present in a substation, it also includes: If the substation does not have a fault recording device, the circuit current effective value corresponding to the three sides of the transformer obtained by the protection device in the substation is read; Based on the voltage level of the transformer corresponding to the power grid, a preset short-circuit current peak value coefficient is selected, and the short-circuit current peak value of the three sides of the transformer is obtained according to the circuit current effective value and the preset short-circuit current peak value coefficient.

4. The transformer operating state evaluation method based on short-circuit impulse according to claim 3, characterized in that, Based on the voltage level of the transformer corresponding to the power grid, a preset short-circuit current peak value coefficient is selected, specifically including: The voltage level of the transformer corresponding to the power grid is obtained, when the voltage level of the power grid is 110kV, the selected preset short-circuit current peak value coefficient is 2.55, and when the voltage level of the power grid is greater than or equal to 220kV, the selected preset short-circuit current peak value coefficient is 2.

69.

5. The transformer operating condition assessment method based on short circuit impulse of claim 1, wherein, The operation life coefficient of the transformer is obtained, specifically including: Obtaining the running age of the transformer, determining the running age grade corresponding to the current running age based on the pre-divided running age grade, and matching the corresponding running age coefficient based on the running age grade.

6. The transformer operating condition assessment method based on short circuit impulse of claim 1, wherein, Obtaining the running state evaluation result of the transformer and the corresponding operation and maintenance strategy based on the total loss value of the anti-short-circuit capability, specifically including: Determine the total loss value of the anti-short-circuit capability corresponding to the current total loss value of the anti-short-circuit capability based on the pre-divided total loss value of the anti-short-circuit capability grade; Match the corresponding transformer running state evaluation result and its operation and maintenance strategy based on the total loss value of the anti-short-circuit capability grade.

7. A short-circuit impulse-based transformer operating state evaluation device, characterized by Including: Short-circuit current peak value acquisition module, short-circuit current impact coefficient acquisition module and running state evaluation module; Wherein, the short-circuit current peak value acquisition module is used to judge whether the fault recording device in the transformer substation has the fault recording device, if yes, the bus breaker current of the transformer three sides in the fault recording device is monitored in real time, when the transformer tripping condition is monitored, the transformer three sides short-circuit current peak value in the fault recording device is collected, wherein the transformer three sides include transformer high voltage side, transformer medium voltage side and transformer low voltage side; The short-circuit current impact coefficient acquisition module is used to calculate the corresponding short-circuit current impact coefficient of the transformer three sides according to the transformer three sides short-circuit current peak value; The running state evaluation module is used to calculate the anti-short-circuit capability loss value of the transformer after short-circuit impact according to the short-circuit current impact coefficient, and the anti-short-circuit capability loss value is accumulated to obtain the running state evaluation result of the transformer and the corresponding operation and maintenance strategy based on the total loss value of the anti-short-circuit capability; Wherein, the anti-short-circuit capability loss value of the transformer after short-circuit impact is calculated according to the short-circuit current impact coefficient, specifically including: Obtaining the running age coefficient of the transformer and the short-circuit impact times of the transformer continuously suffering short-circuit impact within a predetermined time; The running age coefficient, the short-circuit impact times and the corresponding short-circuit current impact coefficient of the transformer three sides are substituted into the preset anti-short-circuit capability loss value calculation formula to calculate and obtain the anti-short-circuit capability loss value of the transformer after short-circuit impact; Wherein, the preset anti-short-circuit capability loss value calculation formula is as follows: LOSS = A - T - e max(CH,CM,CL)·N ; In the formula, A is a constant, taking 1.67, T is the transformer running age coefficient, N is the short-circuit impact times, CH is the short-circuit current impact coefficient of the transformer high voltage side, CM is the short-circuit current impact coefficient of the transformer medium voltage side, and CL is the short-circuit current impact coefficient of the transformer low voltage side.

8. A terminal device, comprising: The computer readable storage medium includes a stored computer program, wherein when the computer program runs, the device where the computer readable storage medium is located executes the transformer running state evaluation method based on short-circuit impact as claimed in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer readable storage medium includes a stored computer program, wherein when the computer program runs, the device where the computer readable storage medium is located executes the transformer running state evaluation method based on short-circuit impact as claimed in any one of claims 1 to 6.

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