Insulation state monitoring system based on energy storage type charging transformer

Abstract

The invention discloses an insulation state monitoring system based on an energy storage type charging transformer, relates to the field of transformers, and solves the problem that an existing insulation state monitoring system is poor in effect. The external insulation monitoring module is used for setting an external insulation monitoring period, carrying out external insulation performance monitoring on the energy storage type charging transformer in the external insulation monitoring period and obtaining an external insulation monitoring coefficient according to a monitoring result, and the internal monitoring module is used for setting an internal insulation monitoring period, carrying out internal insulation performance monitoring on the energy storage type charging transformer in the internal insulation monitoring period and obtaining an external insulation monitoring coefficient. The state evaluation module is used for evaluating the insulation state of the energy storage type charging transformer according to the internal insulation monitoring coefficient and the external insulation monitoring coefficient, and the accuracy of the insulation state monitoring result is improved.

Description

Technical Field

[0001] The present invention belongs to the field of transformers and relates to data analysis technology, specifically an insulation status monitoring system based on an energy storage charging transformer. Background Art

[0002] When the existing insulation status monitoring system monitors the insulation status of an energy storage charging transformer, it has the following specific defects: 1. The existing insulation status monitoring system cannot simultaneously monitor the outer shell insulation and the winding core insulation of the energy storage charging transformer, which easily leads to the lack of comprehensiveness of the monitoring results; 2. The existing insulation status monitoring system cannot combine the working temperature of the energy storage charging transformer to monitor the insulation status, which easily leads to the lack of accuracy of the monitoring results.

[0003] Therefore, we propose an insulation status monitoring system based on an energy storage charging transformer. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide an insulation status monitoring system based on an energy storage charging transformer, and the present invention aims to improve the accuracy and comprehensiveness of the insulation status monitoring of the energy storage charging transformer.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: For the insulation status monitoring system based on an energy storage charging transformer, the specific working processes of each module are as follows: The external monitoring module sets an external insulation monitoring period, analyzes the working temperature of the energy storage charging transformer in the external insulation monitoring period, sets multiple characteristic shell temperatures according to the analysis results, monitors the insulation performance of the energy storage charging transformer at each characteristic shell temperature, and obtains an external insulation monitoring coefficient according to the monitoring results; The internal monitoring module sets an internal insulation monitoring period, analyzes the working temperature of the energy storage charging transformer in the internal insulation monitoring period, sets multiple characteristic winding temperatures according to the analysis results, monitors the insulation performance of the energy storage charging transformer at each characteristic winding temperature, and obtains an internal insulation monitoring coefficient according to the monitoring results; The status evaluation module evaluates the insulation status of the energy storage charging transformer according to the internal insulation monitoring coefficient and the external insulation monitoring coefficient.

[0006] Furthermore, the external insulation performance monitoring of the energy storage charging transformer is as follows: When the energy storage charging transformer is in the energized state, mark the time corresponding to the current moment as the first external characteristic time value. In the time period before the first external characteristic time value, mark a second external characteristic time value, and mark the time period between the first external characteristic time value and the second external characteristic time value as the external insulation monitoring period; Perform a working temperature analysis on the energy storage charging transformer in the external insulation monitoring period to obtain multiple characteristic housing temperatures; When the housing temperature of the energy storage charging transformer is at the housing temperature K1, perform an insulation performance monitoring on the energy storage charging transformer to obtain the K1 housing insulation index value; Obtain the housing insulation index values corresponding to the housing temperatures from K2 to Ka respectively, to obtain the K2 housing insulation index value to the Ka housing insulation index value.

[0007] Furthermore, obtain multiple characteristic housing temperatures as follows: Obtain the housing temperature of the energy storage charging transformer in the external insulation monitoring period, mark the highest housing temperature obtained as the monitoring housing temperature peak value, and mark the lowest housing temperature obtained as the monitoring housing temperature valley value; In the temperature range between the monitoring housing temperature valley value and the monitoring housing temperature peak value, select a characteristic housing temperature at every interval of a characteristic external temperature value to obtain multiple characteristic housing temperatures, and name the multiple characteristic housing temperatures obtained in ascending order of numerical value as the housing temperature K1 to the housing temperature Ka.

[0008] Furthermore, obtain the external insulation monitoring coefficient as follows: In the external insulation monitoring period, obtain the time points when the housing temperature of the energy storage charging transformer is at the housing temperature K1 to obtain multiple K1 housing temperature time points, and arbitrarily select a sample K1 housing time point from the multiple K1 housing temperature time points obtained; Obtain the housing insulation index value corresponding to the sample K1 housing time point; Repeat the process of obtaining the housing insulation index value corresponding to the sample K1 housing time point, obtain the housing insulation index values corresponding to each K1 housing temperature time point respectively to obtain multiple housing insulation index values, and calculate the average of the multiple housing insulation index values obtained to obtain the K1 housing insulation index value; Repeat the process of obtaining the K1 housing insulation index value, obtain the housing insulation index values corresponding to the housing temperatures from K2 to Ka respectively, to obtain the K2 housing insulation index value to the Ka housing insulation index value; In the existing broken line statistical chart template, mark the outer shell insulation index value as the vertical coordinate, mark the outer shell temperature as the horizontal coordinate, use the outer shell temperature from K1 to Ka as the horizontal coordinate, and use the insulation index value from K1 outer shell to Ka outer shell as the vertical coordinate. Create multiple coordinate points in the broken line statistical chart to obtain the insulation coordinate points from K1 to Ka. Obtain the connection slope between every two consecutive insulation coordinate points, and calculate the average of the obtained multiple connection slopes to obtain the external insulation monitoring coefficient.

[0009] Furthermore, obtain the outer shell insulation index value corresponding to the time point of the sample K1 outer shell as follows: Obtain the insulation resistance to the ground of the energy storage charging transformer shell and the grounding terminal at the time point of the sample K1 outer shell to obtain the insulation resistance of the K1 outer shell to the ground; Obtain the external current value of the energy storage charging transformer shell at the time point of the sample K1 outer shell to obtain the leakage current of the K1 outer shell; Obtain the reference insulation resistance to the ground corresponding to the energy storage charging transformer to obtain the reference insulation resistance to the ground, and obtain the reference external current value corresponding to the energy storage charging transformer shell to obtain the reference current value of the shell; Calculate the outer shell insulation index value corresponding to the time point of the sample K1 outer shell through the insulation resistance of the K1 outer shell to the ground, the leakage current of the K1 outer shell, the reference insulation resistance to the ground, and the reference current value of the shell; Calculate the outer shell insulation index value corresponding to the time point of the sample K1 outer shell. The specific formula is as follows: ; Among them, Wjz is the outer shell insulation index value corresponding to the time point of the sample K1 outer shell, Dzk1 is the insulation resistance of the K1 outer shell to the ground, Dlk1 is the leakage current of the K1 outer shell, Dzj is the reference insulation resistance to the ground, and Dlj is the reference current value of the shell.

[0010] Furthermore, obtain the internal insulation monitoring coefficient as follows: When the energy storage charging transformer is in the energized state, mark the time corresponding to the current moment as the first internal characteristic time value. In the time period before the first internal characteristic time value, mark a second internal characteristic time value, and mark the time period between the first internal characteristic time value and the second internal characteristic time value as the internal insulation monitoring period; Analyze the working temperature of the energy storage charging transformer in the internal insulation monitoring period to obtain the winding temperature from R1 to Rb; When the winding temperature of the energy storage charging transformer is at the winding temperature R1, conduct internal insulation performance monitoring on the energy storage charging transformer to obtain the internal insulation index value of R1; Obtain the internal insulation index values corresponding to winding temperature R2 to winding temperature Ra respectively, and obtain the internal insulation index value of R2 to the internal insulation index value of Ra; In the existing broken line statistical chart template, mark the internal insulation index value as the ordinate and the winding temperature as the abscissa. Use winding temperature R1 to winding temperature Ra as the abscissa, and the internal insulation index value of R1 to the internal insulation index value of Ra as the ordinate. Create multiple coordinate points in the broken line statistical chart to obtain the insulation coordinate points of R1 to the insulation coordinate points of Ra. Obtain the connection slope between every two consecutive insulation coordinate points, and calculate the average of the obtained multiple connection slopes to obtain the internal insulation monitoring coefficient.

[0011] Furthermore, obtain multiple characteristic winding temperatures, specifically as follows: Obtain the winding temperature of the energy storage charging transformer during the internal insulation monitoring period, mark the highest winding temperature obtained as the monitoring winding temperature peak value, and mark the lowest winding temperature obtained as the monitoring winding temperature valley value; Within the temperature range between the monitoring winding temperature valley value and the monitoring winding temperature peak value, select a characteristic winding temperature every other characteristic internal temperature value to obtain multiple characteristic winding temperatures, and name the obtained multiple characteristic winding temperatures as winding temperature R1 to winding temperature Ra in ascending order of numerical value.

[0012] Furthermore, obtain the internal insulation index value of R1, specifically as follows: During the internal insulation monitoring period, obtain the time points when the winding temperature of the energy storage charging transformer is at winding temperature R1, obtain multiple R1 winding temperature time points, and arbitrarily select a sample R1 internal time point from the obtained multiple R1 winding temperature time points; Obtain the winding-to-ground insulation resistance of the energy storage charging transformer internal and the grounding terminal at the sample R1 internal time point to obtain the R1 winding-to-ground insulation resistance; Obtain the core-to-ground insulation resistance of the energy storage charging transformer internal at the sample R1 internal time point to obtain the R1 core-to-ground insulation resistance; Obtain the reference winding-to-ground insulation resistance corresponding to the energy storage charging transformer to obtain the reference winding-to-ground insulation resistance, and obtain the reference core-to-ground insulation resistance corresponding to the energy storage charging transformer to obtain the reference core-to-ground insulation resistance; Calculate the internal insulation index value corresponding to the sample R1 internal time point through the R1 winding-to-ground insulation resistance, the R1 core-to-ground insulation resistance, the reference winding-to-ground insulation resistance, and the reference core-to-ground insulation resistance; Calculate the internal insulation index value corresponding to the sample R1 internal time point, and the specific formula is as follows: ; Among them, Njz is the internal insulation index value corresponding to the internal time point of sample R1, Nzk1 is the insulation resistance of the R1 winding to the ground, Nlk1 is the insulation resistance of the R1 iron core to the ground, Nzj is the insulation resistance of the reference winding to the ground, and Nlj is the insulation resistance of the reference iron core to the ground; Repeat the process of obtaining the internal insulation index value corresponding to the internal time point of sample R1, obtain the internal insulation index value corresponding to each R1 winding temperature time point respectively, obtain multiple internal insulation index values, and calculate the average of the obtained multiple internal insulation index values to obtain the internal insulation index value of R1.

[0013] Furthermore, the insulation state of the energy storage type charging transformer is evaluated as follows: Obtain the internal insulation monitoring coefficient and the external insulation monitoring coefficient; Obtain the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient reference interval; Evaluate the insulation state of the energy storage type charging transformer according to the internal insulation monitoring coefficient, the external insulation monitoring coefficient, the internal insulation monitoring coefficient reference interval, and the external insulation monitoring coefficient reference interval.

[0014] Furthermore, the evaluation process is as follows: If the internal insulation monitoring coefficient is within the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient is within the external insulation monitoring coefficient reference interval, it is evaluated that the insulation state of the energy storage type charging transformer is normal; If the internal insulation monitoring coefficient is not within the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient is within the external insulation monitoring coefficient reference interval, it is evaluated that the insulation state of the energy storage type charging transformer is abnormal; If the internal insulation monitoring coefficient is within the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient is not within the external insulation monitoring coefficient reference interval, it is evaluated that the insulation state of the energy storage type charging transformer is abnormal; If the internal insulation monitoring coefficient is not within the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient is not within the external insulation monitoring coefficient reference interval, it is evaluated that the insulation state of the energy storage type charging transformer is abnormal.

[0015] To sum up, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The present invention monitors the shell insulation and the winding iron core insulation of the energy storage type charging transformer by obtaining the external insulation monitoring coefficient and the internal insulation monitoring coefficient, making the monitoring results more comprehensive; 2. The present invention monitors the insulation state by combining the working temperature of the energy storage type charging transformer, thereby making the monitoring results more accurate. Description of the Drawings

[0016] For the convenience of those skilled in the art to understand, the present invention will be further described below in conjunction with the accompanying drawings.

[0017] Figure 1 is the overall system block diagram of the present invention; Figure 2 is the schematic diagram of the K1 insulation coordinate point of the present invention; Figure 3 is the schematic diagram of the R1 insulation coordinate point of the present invention. Specific embodiments

[0018] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0019] Embodiment 1 Please refer to Figure 1 , the present invention provides a technical solution: an insulation state monitoring system based on a storage-type charging transformer, including an external monitoring module, an internal monitoring module, a state evaluation module and a server. The external monitoring module, the internal monitoring module and the state evaluation module are respectively connected to the server, and the server controls the external monitoring module, the internal monitoring module and the state evaluation module respectively; The external monitoring module sets an external insulation monitoring period, analyzes the working temperature of the storage-type charging transformer in the external insulation monitoring period, sets a plurality of characteristic shell temperatures according to the analysis results, monitors the insulation performance of the storage-type charging transformer at each characteristic shell temperature, and obtains an external insulation monitoring coefficient according to the monitoring results; Specifically as follows: When the storage-type charging transformer is in the energized state, mark the time corresponding to the current moment as the first external characteristic time value. In the period before the first external characteristic time value, mark a second external characteristic time value, and mark the period between the first external characteristic time value and the second external characteristic time value as the external insulation monitoring period; It should be noted here that: In the present application, as the time value corresponding to the current moment changes, the first external characteristic time value and the second external characteristic time value also change accordingly, so as to realize the dynamic update of the external insulation monitoring period.

[0020] Obtain the casing temperature of the energy storage charging transformer during the external insulation monitoring period, mark the highest value of the obtained casing temperature as the monitored casing temperature peak value, and mark the lowest value of the obtained casing temperature as the monitored casing temperature trough value; Within the temperature range between the monitored casing temperature trough value and the monitored casing temperature peak value, select a characteristic casing temperature at every interval of a characteristic external temperature value to obtain multiple characteristic casing temperatures, and name the obtained multiple characteristic casing temperatures as casing temperature K1 to casing temperature Ka in ascending order of numerical value; It should be noted here that: In this application, K involved here is the identifier corresponding to the characteristic casing temperature of the energy storage charging transformer, a is the numerical value corresponding to the characteristic casing temperature of the energy storage charging transformer, and a is an integer greater than 0; When the casing temperature of the energy storage charging transformer is at casing temperature K1, monitor the insulation performance of the energy storage charging transformer to obtain the K1 casing insulation index value; Specifically as follows: During the external insulation monitoring period, obtain the time points when the casing temperature of the energy storage charging transformer is at casing temperature K1 to obtain multiple K1 casing temperature time points, and randomly select a sample K1 casing time point from the obtained multiple K1 casing temperature time points; Obtain the insulation resistance to the ground between the casing of the energy storage charging transformer and the grounding terminal at the sample K1 casing time point to obtain the K1 casing insulation resistance to the ground; Obtain the external current value of the casing of the energy storage charging transformer at the sample K1 casing time point to obtain the K1 casing leakage current; Obtain the reference insulation resistance to the ground corresponding to the energy storage charging transformer to obtain the reference insulation resistance to the ground, and obtain the reference external current value corresponding to the casing of the energy storage charging transformer to obtain the casing reference current value; It should be noted here that: In this application, the reference insulation resistance to the ground refers to the insulation resistance value of an electrical equipment or system relative to the ground (or reference ground) under specific conditions. The reference insulation resistance to the ground involved here is set to 0.5 MΩ; In this application, the casing reference current refers to the current value passing through the casing of an electrical equipment. The specific value of the casing reference current involved here is 0 A.

[0021] Calculate the casing insulation index value corresponding to the sample K1 casing time point through the K1 casing insulation resistance to the ground, the K1 casing leakage current, the reference insulation resistance to the ground, and the casing reference current value; Calculate the casing insulation index value corresponding to the sample K1 casing time point. The specific formula is as follows: ; Among them, Wjz is the shell insulation index value corresponding to the time point of the shell of sample K1, Dzk1 is the insulation resistance of the K1 shell to the ground, Dlk1 is the leakage current of the K1 shell, Dzj is the reference insulation resistance to the ground, and Dlj is the reference current value of the shell; Repeat the process of obtaining the shell insulation index value corresponding to the time point of the shell of sample K1, respectively obtain the shell insulation index values corresponding to each time point of the K1 shell temperature, obtain multiple shell insulation index values, and calculate the average of the obtained multiple shell insulation index values to obtain the K1 shell insulation index value; It should be noted here that: In this application, the K1 shell insulation index value involved here represents the insulation state of the energy storage charging transformer shell at the time point of the sample K1 shell. The larger the K1 shell insulation index value, the worse the insulation state of the energy storage charging transformer shell at the time point of the sample K1 shell; In specific implementation, there are the following experimental data: Through experimental measurement, the insulation resistance of the K1 shell to the ground is: Dzk1 = 1.0 MΩ, the leakage current of the K1 shell is: Dlk1 = 0.01 A, and the calculated K1 shell insulation index value is 0.51.

[0022] Repeat the process of obtaining the K1 shell insulation index value, respectively obtain the shell insulation index values corresponding to the shell temperature from K2 to Ka, and obtain the K2 shell insulation index value to the Ka shell insulation index value; Please refer to Figure 2 , in the existing line chart template, mark the shell insulation index value as the ordinate and the shell temperature as the abscissa. Use the shell temperature from K1 to Ka as the abscissa and the K1 shell insulation index value to the Ka shell insulation index value as the ordinate. Create multiple coordinate points in the line chart to obtain the K1 insulation coordinate point to the Ka insulation coordinate point. Obtain the connection slope between every two consecutive insulation coordinate points, and calculate the average of the obtained multiple connection slopes to obtain the external insulation monitoring coefficient; The external monitoring module obtains the external insulation monitoring coefficient and transmits it to the state evaluation module; The internal monitoring module sets an internal insulation monitoring period, analyzes the working temperature of the energy storage charging transformer during the internal insulation monitoring period, sets multiple characteristic winding temperatures according to the analysis results, monitors the insulation performance of the energy storage charging transformer at each characteristic winding temperature, and obtains the internal insulation monitoring coefficient according to the monitoring results; Specifically as follows: When the energy storage charging transformer is in the energized state, mark the time corresponding to the current moment as the first internal characteristic time value. In the time period before the first internal characteristic time value, mark a second internal characteristic time value, and mark the time period between the first internal characteristic time value and the second internal characteristic time value as the internal insulation monitoring period; It should be noted here that: In this application, as the time value corresponding to the current moment changes, the first internal characteristic time value and the second internal characteristic time value also change accordingly, so as to realize the dynamic update of the internal insulation monitoring period.

[0023] Obtain the winding temperature of the energy storage charging transformer in the internal insulation monitoring period, mark the highest value of the obtained winding temperature as the monitored winding temperature peak value, and mark the lowest value of the obtained winding temperature as the monitored winding temperature valley value; In the temperature range between the monitored winding temperature valley value and the monitored winding temperature peak value, select a characteristic winding temperature every other characteristic internal temperature value to obtain multiple characteristic winding temperatures, and name the obtained multiple characteristic winding temperatures in ascending order of numerical value as winding temperature R1 to winding temperature Rb; It should be noted here that: In this application, R involved here is the identifier corresponding to the characteristic winding temperature of the energy storage charging transformer, b is the numerical value corresponding to the characteristic winding temperature of the energy storage charging transformer, and b is an integer greater than 0; When the winding temperature of the energy storage charging transformer is at winding temperature R1, perform internal insulation performance monitoring on the energy storage charging transformer to obtain the R1 internal insulation index value; Specifically as follows: In the internal insulation monitoring period, obtain the time points when the winding temperature of the energy storage charging transformer is at winding temperature R1, obtain multiple R1 winding temperature time points, and arbitrarily select a sample R1 internal time point from the obtained multiple R1 winding temperature time points; Obtain the winding-to-ground insulation resistance of the energy storage charging transformer internal and the grounding terminal at the sample R1 internal time point to obtain the R1 winding-to-ground insulation resistance; Obtain the core-to-ground insulation resistance of the energy storage charging transformer internal at the sample R1 internal time point to obtain the R1 core-to-ground insulation resistance; Obtain the reference winding-to-ground insulation resistance corresponding to the energy storage charging transformer to obtain the reference winding-to-ground insulation resistance, and obtain the reference core-to-ground insulation resistance corresponding to the energy storage charging transformer to obtain the reference core-to-ground insulation resistance; It should be noted here that: The ground insulation resistance of the reference winding involved here is specifically the insulation resistance of the winding to the ground measured under a 220V DC voltage for a brand-new (just out of the factory or after overhaul) energy storage charging transformer, and this value is used as a reference standard for subsequent evaluation of the insulation condition of the transformer; The ground insulation resistance of the reference iron core involved here is specifically the insulation resistance of the iron core to the ground measured under a 220V DC voltage for a brand-new (just out of the factory or after overhaul) energy storage charging transformer, and this value is used as a reference standard for subsequent evaluation of the insulation condition of the transformer; In this application, the ground insulation resistance of the reference winding and the ground insulation resistance of the reference iron core involved here need to be specifically set according to the electrical data inside the energy storage charging transformer.

[0024] The internal insulation index value corresponding to the internal time point of sample R1 is obtained by calculating the insulation resistance of winding R1 to the ground, the insulation resistance of iron core R1 to the ground, the insulation resistance of the reference winding to the ground, and the insulation resistance of the reference iron core to the ground; Calculate the internal insulation index value corresponding to the internal time point of sample R1. The specific formula is as follows: ; Among them, Njz is the internal insulation index value corresponding to the internal time point of sample R1, Nzk1 is the insulation resistance of winding R1 to the ground, Nlk1 is the insulation resistance of iron core R1 to the ground, Nzj is the insulation resistance of the reference winding to the ground, and Nlj is the insulation resistance of the reference iron core to the ground; Repeat the process of obtaining the internal insulation index value corresponding to the internal time point of sample R1, respectively obtain the internal insulation index values corresponding to each internal time point of winding temperature R1, and obtain multiple internal insulation index values, and calculate the average of the obtained multiple internal insulation index values to obtain the internal insulation index value of R1; It should be noted here that: In this application, the internal insulation index value of R1 involved here represents the insulation state inside the energy storage charging transformer at the internal time point of sample R1. The larger the internal insulation index value of R1, the worse the insulation state inside the energy storage charging transformer at the internal time point of sample R1; Repeat the process of obtaining the internal insulation index value of R1, respectively obtain the internal insulation index values corresponding to winding temperature R2 to winding temperature Rb, and obtain the internal insulation index value of R2 to the internal insulation index value of Rb; Please refer to Figure 3, in the existing broken line statistical chart template, mark the internal insulation index value as the ordinate and the winding temperature as the abscissa. Take the winding temperatures from R1 to Rb as the abscissa, and the internal insulation index values from R1 to Rb as the ordinate. Create multiple coordinate points in the broken line statistical chart to obtain the insulation coordinate points from R1 to Rb. Obtain the connection slope between every two consecutive insulation coordinate points, and calculate the average of the obtained multiple connection slopes to get the internal insulation monitoring coefficient; The internal monitoring module obtains the internal insulation monitoring coefficient and transports it to the status evaluation module; The status evaluation module evaluates the insulation status of the energy storage type charging transformer according to the internal insulation monitoring coefficient and the external insulation monitoring coefficient; Specifically as follows: Obtain the internal insulation monitoring coefficient and the external insulation monitoring coefficient respectively; Obtain the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient reference interval; It should be noted here that: The internal insulation monitoring coefficient reference interval involved here is the interval composed of the internal insulation monitoring coefficients corresponding to the energy storage type charging transformers in the normal insulation state. The external insulation monitoring coefficient reference interval involved here is the interval composed of the external insulation monitoring coefficients corresponding to the energy storage type charging transformers in the normal insulation state; In this application, through multiple tests, the internal insulation monitoring coefficient reference interval is set as [0.6, 0.8], and the external insulation monitoring coefficient reference interval is set as [0.6, 0.7].

[0025] If the internal insulation monitoring coefficient is within the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient is within the external insulation monitoring coefficient reference interval, then it is evaluated that the insulation status of the energy storage type charging transformer is normal; If the internal insulation monitoring coefficient is not within the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient is within the external insulation monitoring coefficient reference interval, then it is evaluated that the insulation status of the energy storage type charging transformer is abnormal; If the internal insulation monitoring coefficient is within the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient is not within the external insulation monitoring coefficient reference interval, then it is evaluated that the insulation status of the energy storage type charging transformer is abnormal; If the internal insulation monitoring coefficient is not within the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient is not within the external insulation monitoring coefficient reference interval, then it is evaluated that the insulation status of the energy storage type charging transformer is abnormal.

[0026] It should be noted here that: In this application, the abnormal insulation state of the energy storage charging transformer involved here includes the interval boundaries corresponding to the internal insulation monitoring coefficient reference interval and the external insulation monitoring coefficient reference interval.

[0027] In this application, if there are corresponding calculation formulas, the above calculation formulas are all dimensionless and take their numerical values for calculation. The coefficients such as the weight coefficient and the proportionality coefficient in the formula are set to obtain a result value by quantifying each parameter. Regarding the magnitudes of the weight coefficient and the proportionality coefficient, as long as the proportional relationship between the parameters and the result value is not affected.

[0028] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the present invention to only the specific embodiments. Obviously, according to the content of this specification, many modifications and variations can be made. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. The insulation status monitoring system based on the energy storage charging transformer is characterized by: include: External monitoring module setting: used for external insulation monitoring cycle, to analyze the working temperature of the energy storage charging transformer in the external insulation monitoring cycle, to obtain multiple characteristic shell temperatures according to the analysis results, to monitor the insulation performance of the energy storage charging transformer at the characteristic shell temperature, and to obtain the external insulation monitoring coefficient according to the monitoring results; Internal monitoring module: used to set an internal insulation monitoring cycle, perform working temperature analysis on the energy storage charging transformer in the internal insulation monitoring cycle, obtain multiple characteristic winding temperatures according to the analysis results, perform insulation performance monitoring on the energy storage charging transformer at the characteristic winding temperature, and obtain the internal insulation monitoring coefficient according to the monitoring results; Status assessment module: used to assess the insulation status of the energy storage charging transformer based on the internal insulation monitoring factor and the external insulation monitoring factor.

2. The insulation status monitoring system based on the energy storage charging transformer according to claim 1 is characterized in that: The external insulation performance of the energy storage charging transformer is monitored as follows: When the energy storage charging transformer is powered on, an external insulation monitoring cycle is marked; Perform operating temperature analysis on the energy storage charging transformer in the external insulation monitoring cycle to obtain multiple characteristic shell temperatures; When the shell temperature of the energy storage charging transformer is at the shell temperature K1, the insulation performance of the energy storage charging transformer is monitored to obtain the K1 shell insulation index value; The shell insulation index values ​​corresponding to the shell temperature K2 to the shell temperature Ka are obtained respectively, and the shell insulation index value K2 to the shell insulation index value Ka are obtained.

3. The insulation status monitoring system based on the energy storage charging transformer according to claim 2 is characterized in that: Multiple characteristic shell temperatures are obtained as follows: The shell temperature of the energy storage charging transformer in the external insulation monitoring cycle is obtained, and the maximum shell temperature value obtained is marked as the monitoring shell temperature peak value, and the minimum shell temperature value obtained is marked as the monitoring shell temperature valley value; In the temperature range between the monitored casing temperature valley value and the monitored casing temperature peak value, a characteristic casing temperature is selected at every interval of a characteristic external temperature value to obtain casing temperatures K1 to Ka.

4. The insulation status monitoring system based on the energy storage charging transformer according to claim 2 is characterized in that: The external insulation monitoring coefficient is obtained as follows: In the external insulation monitoring cycle, the time point when the shell temperature of the energy storage charging transformer is at the shell temperature K1 is obtained to obtain multiple K1 shell temperature time points, and a sample K1 shell time point is arbitrarily selected from the multiple K1 shell temperature time points obtained; Obtain the shell insulation index value corresponding to the shell time point of sample K1; The shell insulation index value corresponding to each K1 shell temperature time point is obtained respectively to obtain a plurality of shell insulation index values, and the average of the obtained plurality of shell insulation index values ​​is calculated to obtain the K1 shell insulation index value; The shell insulation index values ​​corresponding to the shell temperature K2 to the shell temperature Ka are obtained respectively, and the shell insulation index value K2 to the shell insulation index value Ka are obtained; In the existing broken line chart template, the shell insulation index value is marked as the vertical axis, the shell temperature is marked as the horizontal axis, the shell temperature K1 to the shell temperature Ka are used as the horizontal axis, and the K1 shell insulation index value to the Ka shell insulation index value are used as the vertical axis. Multiple coordinate points are created in the broken line chart to obtain the K1 insulation coordinate point to the Ka insulation coordinate point, obtain the slope of the connecting line between each two consecutive insulation coordinate points, and average the multiple connecting line slopes obtained to obtain the external insulation monitoring coefficient.

5. The insulation status monitoring system based on the energy storage charging transformer according to claim 4 is characterized in that: The shell insulation index value corresponding to the shell time point of sample K1 is obtained, as follows: Obtain the insulation resistance of the energy storage charging transformer housing and the ground terminal to the ground at the time point of the sample K1 housing, and obtain the insulation resistance of the K1 housing to the ground; Obtain the external current value of the energy storage charging transformer housing at the sample K1 housing time point to obtain the K1 housing leakage current; Obtain a reference insulation resistance to ground corresponding to the energy storage charging transformer, obtain a reference insulation resistance to ground, obtain a reference external current value corresponding to the housing of the energy storage charging transformer, and obtain a housing reference current value; The shell insulation index value Wjz corresponding to the sample K1 shell time point is obtained by calculating the K1 shell insulation resistance to ground Dzk1, K1 shell leakage current Dlk1, reference insulation resistance to ground Dzj and shell reference current value Dlj. The specific formula is as follows: 。 6. The insulation status monitoring system based on the energy storage charging transformer according to claim 1 is characterized in that: The internal insulation monitoring coefficient is obtained as follows: When the energy storage charging transformer is powered on, an internal insulation monitoring cycle is marked; Performing operating temperature analysis on the energy storage charging transformer in the internal insulation monitoring cycle to obtain winding temperatures R1 to Rb; When the winding temperature of the energy storage charging transformer is between the winding temperature R1 and the winding temperature Ra, the internal insulation performance of the energy storage charging transformer is monitored to obtain the internal insulation index value of R1 to the internal insulation index value of Ra; In the existing broken line chart template, the internal insulation index value is marked as the vertical coordinate, the winding temperature is marked as the horizontal coordinate, the winding temperature R1 to the winding temperature Ra is used as the horizontal coordinate, and the R1 internal insulation index value to the Ra internal insulation index value is used as the vertical coordinate. Multiple coordinate points are created in the broken line chart to obtain the R1 insulation coordinate point to the Ra insulation coordinate point, obtain the slope of the connecting line between each two consecutive insulation coordinate points, and calculate the average of the multiple connecting line slopes obtained to obtain the internal insulation monitoring coefficient.

7. The insulation status monitoring system based on the energy storage charging transformer according to claim 6 is characterized in that: Multiple characteristic winding temperatures are obtained, as follows: The winding temperature of the energy storage charging transformer in the internal insulation monitoring cycle is obtained, the maximum value of the winding temperature obtained is marked as the peak value of the monitored winding temperature, and the minimum value of the winding temperature obtained is marked as the valley value of the monitored winding temperature; In the temperature range between the monitored winding temperature valley value and the monitored winding temperature peak value, a characteristic winding temperature is selected at each interval of a characteristic internal temperature value, and the obtained multiple characteristic winding temperatures are named winding temperature R1 to winding temperature Ra in order from small to large values.

8. The insulation status monitoring system based on the energy storage charging transformer according to claim 6 is characterized in that: The internal insulation index value of R1 is obtained as follows: In the internal insulation monitoring cycle, the time point when the winding temperature of the energy storage charging transformer is at the winding temperature R1 is obtained to obtain multiple R1 winding temperature time points, and a sample R1 internal time point is arbitrarily selected from the multiple R1 winding temperature time points obtained; Obtain the insulation resistance of the winding to ground between the energy storage charging transformer and the ground terminal at the time point inside the sample R1, and obtain the insulation resistance of the R1 winding to ground; Obtain the insulation resistance of the core to ground inside the energy storage charging transformer at the time point inside the sample R1, and obtain the insulation resistance of the core to ground of R1; Obtain the reference winding insulation resistance to ground corresponding to the energy storage charging transformer, obtain the reference winding insulation resistance to ground, obtain the reference iron core insulation resistance to ground corresponding to the energy storage charging transformer, and obtain the reference iron core insulation resistance to ground; The internal insulation index value Njz corresponding to the internal time point of sample R1 is obtained by calculating the insulation resistance Nzk1 of R1 winding to ground, the insulation resistance Nlk1 of R1 core to ground, the insulation resistance Nzj of reference winding to ground and the insulation resistance Nlj of reference core to ground. The specific formula is as follows: ； The internal insulation index value corresponding to each R1 winding temperature time point is obtained respectively to obtain a plurality of internal insulation index values, and the average of the obtained plurality of internal insulation index values ​​is calculated to obtain the R1 internal insulation index value.

9. The insulation status monitoring system based on the energy storage charging transformer according to claim 1 is characterized in that: The insulation status of the energy storage charging transformer is evaluated as follows: Obtain internal insulation monitoring factor and external insulation monitoring factor; Obtaining the internal insulation monitoring factor reference interval and the external insulation monitoring factor reference interval; The insulation status of the energy storage charging transformer is evaluated based on the internal insulation monitoring factor, the external insulation monitoring factor, the internal insulation monitoring factor reference range and the external insulation monitoring factor reference range.

10. The insulation status monitoring system based on the energy storage charging transformer according to claim 9 is characterized in that: The evaluation process is as follows: If the internal insulation monitoring coefficient is within the internal insulation monitoring coefficient reference range, and the external insulation monitoring coefficient is within the external insulation monitoring coefficient reference range, then the insulation status of the energy storage charging transformer is assessed to be normal; If the internal insulation monitoring coefficient is not within the internal insulation monitoring coefficient reference interval, and the external insulation monitoring coefficient is within the external insulation monitoring coefficient reference interval, then the insulation state of the energy storage charging transformer is assessed to be abnormal; If the internal insulation monitoring coefficient is within the internal insulation monitoring coefficient reference interval, and the external insulation monitoring coefficient is not within the external insulation monitoring coefficient reference interval, then the insulation state of the energy storage charging transformer is assessed to be abnormal; If the internal insulation monitoring coefficient is not within the internal insulation monitoring coefficient reference range, and the external insulation monitoring coefficient is not within the external insulation monitoring coefficient reference range, then it is assessed that the insulation state of the energy storage charging transformer is abnormal.

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