A primary and secondary fused circuit breaker

Abstract

The application discloses a primary and secondary fusion intelligent circuit breaker on a column, which comprises a fault detection module, a protection action module, a reclosing module and an information reporting module. The fault detection module collects multi-dimensional electrical quantities through current and voltage transformers, judges the fault and identifies the type in combination with dynamic normal range and duration threshold; the protection action module calculates the fault distance based on the corrected impedance, determines whether to act in combination with the current direction and the protection range, and selects the protection level according to the fault severity; the reclosing module dynamically sets the observation time window, distinguishes the transient or permanent fault through the retest verification mechanism, and adaptively adjusts the reclosing strategy; the information reporting module uploads the fault related information. The application solves the problems of the traditional circuit breaker, such as high misjudgment rate, poor protection selectivity, rigid reclosing logic and the like, and significantly improves the accuracy, speed and self-healing ability of the power distribution network fault processing.

Description

Technical Field

[0001] This invention relates to the field of circuit breaker control, and specifically to a primary and secondary integrated pole-mounted intelligent circuit breaker. Background Technology

[0002] As power distribution networks develop towards intelligence and automation, pole-mounted circuit breakers, as key equipment in distribution lines, directly affect the safe and stable operation of the power grid through their protection performance and operational reliability. Currently, distribution network line faults are complex and diverse, and are susceptible to transient disturbances and load fluctuations. Traditional circuit breakers often employ single electrical quantity criteria or fixed threshold protection strategies, which have the following shortcomings:

[0003] (1) Fault judgment relies on a single parameter of current or voltage and is easily affected by instantaneous disturbances, leading to misjudgment or omission, and it is difficult to fully cover the characteristics of various faults.

[0004] (2) The fault type identification accuracy is low, and there is a lack of comprehensive comparison of multi-dimensional electrical quantities, which makes it impossible to accurately distinguish different faults and affects the efficiency of fault diagnosis.

[0005] (3) The fault location did not take into account the influence of factors such as line temperature and aging on impedance and did not correct it, resulting in a large distance measurement error, causing misjudgment of the protection range, which could easily lead to over-level tripping.

[0006] (4) The reclosing strategy lacks a dynamic adjustment mechanism and the observation time window is fixed. It is easy to cause equipment life and grid stability due to failure to recover from instantaneous faults or accidental reclosing due to permanent faults. Summary of the Invention

[0007] To address the aforementioned problems, this invention proposes a primary and secondary integrated pole-mounted intelligent circuit breaker to achieve the function of controlling the circuit breaker.

[0008] The technical solution adopted by this invention to solve its technical problem is: This invention provides a primary and secondary integrated pole-mounted intelligent circuit breaker, comprising:

[0009] Fault detection module: Real-time acquisition of current and voltage data of distribution network lines, fault judgment based on preset line fault judgment rules, and after identifying the fault, determining the fault type based on the characteristics of abnormal electrical quantities and executing protection action modules.

[0010] Protection Action Module: Locates the fault point and determines whether the fault point is within the protection range of the circuit breaker based on the fault current flow direction. If it is within the protection range, the corresponding current protection level is selected according to the fault distance and severity, and the protection action is triggered to trip the circuit breaker; otherwise, the protection action is not triggered.

[0011] Reclosing module: Sets an observation time window after tripping, monitors the electrical parameters of the line after tripping, and makes a preliminary judgment on the nature of the fault. If it is a transient fault, it performs a reclosing operation and verifies the judgment result based on the tripping situation after reclosing. If it is a permanent fault, it remeasures the electrical parameters of the line after a set interval to verify the nature of the fault. If it is verified to be a permanent fault, it blocks reclosing. If it is verified to be a misjudgment, it performs a reclosing operation.

[0012] Information reporting module: Uploads fault information, tripping information and reclosing information to the distribution network master station.

[0013] Compared with existing technologies, the primary and secondary integrated pole-mounted intelligent circuit breaker of the present invention has the following advantages:

[0014] 1. Improve fault identification accuracy: By comprehensively comparing multiple parameters such as current and voltage, and introducing a duration threshold, misjudgment based on a single parameter and interference from instantaneous disturbances are avoided, thereby improving the comprehensiveness and adaptability of fault diagnosis.

[0015] 2. Accurately identify fault types: Based on multi-dimensional electrical quantities such as three-phase voltage, current and sequence components, the system compares them with preset fault characteristics, prioritizing complete matching of simple faults, and calculating the matching degree of complex faults through weighted averages to reduce misjudgments and provide a clear basis for fault diagnosis.

[0016] 3. Optimize fault location accuracy: Combine line temperature and aging degree to correct the impedance per unit length, improve the accuracy of fault distance calculation, and at the same time, ensure the selectivity of protection action by using the dual criteria of current flow direction and protection range, and avoid false tripping of faults outside the protection zone.

[0017] 4. Improve the rationality of reclosing strategy: Based on historical data and reclosing delay, dynamically set the observation time window, and verify the nature of the fault through retesting to achieve accurate reclosing for instantaneous faults and reliable blocking for permanent faults, thereby reducing equipment damage and power outage time.

[0018] 5. Achieve graded adaptation of protection actions: Match the optimal protection level according to the fault distance and severity to avoid over-level tripping, shorten the disconnection time, improve the reliability of power grid operation, and reduce power outage losses. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a system module connection diagram of the present invention.

[0021] Figure 2 This is a flowchart illustrating the setting of the observation time window in this invention.

[0022] Figure 3 This is a flowchart illustrating the operation of the reclosing module of the present invention. Detailed Implementation

[0023] The technical solutions of 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.

[0024] Please see Figure 1 As shown, the present invention provides a primary and secondary integrated pole-mounted intelligent circuit breaker, including a fault detection module, a protection action module, a reclosing module, and an information reporting module.

[0025] The protection action module is connected to the fault detection module and the reclosing module respectively, and the information reporting module is connected to the reclosing module.

[0026] The fault detection module collects current and voltage data of the distribution network lines in real time, judges faults based on preset line fault judgment rules, and determines the fault type based on the abnormal electrical quantity characteristics after identifying the fault, and executes the protection action module.

[0027] Furthermore, the specific working process of fault judgment in the fault detection module is as follows:

[0028] Current and voltage data of the distribution network lines are collected in real time by current transformers and voltage transformers. The current data includes phase current and zero-sequence current, and the voltage data includes phase voltage, line voltage and zero-sequence voltage.

[0029] The collected current and voltage data are compared with the corresponding normal ranges stored in the database.

[0030] When any current or voltage data exceeds its normal range, an abnormal signal is generated and timing is started.

[0031] If the duration of the abnormal signal exceeds a preset duration threshold, it is determined that a fault has occurred in the power distribution network line.

[0032] It should be noted that abnormal current data may indicate a short circuit, grounding fault, or load abnormality, while abnormal voltage data may reflect a line break, grounding fault, or system disturbance. Combining both can improve the comprehensiveness and accuracy of line fault identification and avoid misjudgment based on a single parameter.

[0033] It should be noted that the normal ranges for current and voltage data are obtained in two ways: one is through historical data statistics, based on long-term monitoring data during normal line operation, to determine a reasonable range through statistical analysis; the other is through theoretical calculations, calculating the allowable range based on line parameters and power grid operation standards. Furthermore, the normal ranges for current and voltage data are dynamically adjusted and updated regularly in conjunction with actual operating conditions such as seasons and load changes to ensure adaptability.

[0034] It should be noted that by setting a duration threshold, an abnormal signal is only considered a fault if it continuously exceeds this threshold. Adding a time delay when judging line faults ensures that the fault is a continuous abnormality rather than a brief fluctuation, thus avoiding misjudgments caused by instantaneous disturbances.

[0035] It should be noted that the duration threshold can be preset based on engineering experience or optimized using a limited number of test data. For example, historical data on the types and durations of faults in the distribution network can be collected first, then the correlation between different fault characteristics and the reliability of fault judgment can be analyzed. Statistical analysis or machine learning methods can be used to determine the reasonable duration corresponding to each fault characteristic. Finally, through normalization or threshold grading, the analysis results can be transformed into specific duration thresholds whose values ​​meet the balance requirements of protection speed and reliability.

[0036] In this embodiment, the present invention compares multiple parameters, including current and voltage, and introduces a duration threshold to avoid misjudgment of a single parameter and interference from instantaneous disturbances, thereby improving the comprehensiveness and adaptability of fault diagnosis.

[0037] Furthermore, the specific process for determining the fault type in the fault detection module is as follows:

[0038] Based on the current and voltage data of the line, electrical quantity data is extracted from it. The electrical quantity data includes three-phase voltage, three-phase current, zero-sequence component and negative-sequence component.

[0039] The electrical quantity data is compared with the abnormal electrical quantity characteristics corresponding to each preset fault type. The abnormal electrical quantity characteristics include voltage characteristics and current characteristics.

[0040] If the electrical quantity data completely matches at least one of the abnormal voltage characteristics and abnormal current characteristics corresponding to a certain fault type, then the line fault type is determined to be that fault type.

[0041] If no perfectly matching fault type exists, count the number of consistent feature items in the abnormal electrical quantity characteristics corresponding to each fault type from the electrical quantity data. Then, perform a weighted summation of each consistent feature item according to a preset weight to obtain the matching degree of each fault type. The fault type with the highest matching degree is taken as the line fault type.

[0042] In one specific embodiment, the fault types include three-phase short circuit, two-phase short circuit, two-phase ground fault, single-phase ground fault, and overload. The corresponding abnormal electrical quantity characteristics are as follows: a three-phase short circuit exhibits a symmetrical drop in three-phase voltage to near zero and a symmetrical surge in current; a two-phase short circuit is characterized by the fault phase voltage returning to zero, the non-fault phase voltage increasing, and the fault phase current increasing in the reverse direction with a negative sequence component; a two-phase ground fault, in addition to the characteristics of a two-phase short circuit, also exhibits zero-sequence voltage and current components; a single-phase ground fault shows the fault phase voltage returning to zero, the non-fault phase voltage rising to line voltage, and only the fault phase current increasing with a zero-sequence component; an overload is characterized by a slight decrease in three-phase voltage and a symmetrical increase in current without zero-sequence or negative-sequence components. This characteristic system provides clear criteria for fault diagnosis by quantifying the electrical quantity changes of each fault.

[0043] It should be noted that different fault types will cause specific abnormal patterns in the voltage and current of the line. Therefore, the fault type can be determined based on the abnormal voltage and current characteristics.

[0044] It should be noted that the weights of each feature item in the abnormal electrical quantity characteristics can be set based on domain experience or obtained through statistical analysis of historical fault data. For example, first collect case data on line fault types and their corresponding electrical quantity characteristics, then calculate the correlation coefficients between different feature items and fault types, use regression analysis or machine learning methods to quantify the contribution of each feature item to fault identification, and finally convert the contribution into weight values ​​through normalization, ensuring that the sum of all weights is 1.

[0045] It should be noted that this invention determines the fault type by comprehensively comparing multiple electrical quantities, reducing the possibility of misjudgment based on a single signal and improving the accuracy of fault diagnosis. Furthermore, during the comparison process, fault types that match completely are prioritized to improve the identification efficiency of simple faults. For complex faults, the matching degree is quantified through weighted fusion to ensure the reliability of the results.

[0046] It should be noted that clearly identifying the fault type can accurately pinpoint the problem, shorten the troubleshooting time, and reduce the impact of power outages. At the same time, the accumulation of fault type data is beneficial for analyzing weak links in the line, providing a basis for power grid upgrades or equipment selection.

[0047] In this embodiment, the present invention compares three-phase voltage, current and sequence components and other multi-dimensional electrical quantities with preset fault characteristics, giving priority to complete matching of simple faults, and calculating the matching degree of complex faults by weighting, thereby reducing misjudgment and providing a clear basis for fault diagnosis.

[0048] The protection action module locates the fault point and determines whether the fault point is within the protection range of the circuit breaker based on the direction of the fault current. If it is within the protection range, the corresponding current protection level is selected according to the fault distance and severity, and the protection action is triggered to trip the circuit breaker. Otherwise, the protection action is not triggered.

[0049] Furthermore, the specific process of locating the fault point in the protection action module is as follows:

[0050] Based on the type of line fault, the corresponding impedance calculation model is extracted from the database, and the impedance of the fault circuit is calculated by combining it with electrical quantity data.

[0051] Obtain line parameters, including conductor material, cross-sectional area, and installation method. Based on the preset correspondence between line parameters and impedance per unit length, determine the preliminary calibrated impedance per unit length.

[0052] Based on historical impedance data, a line temperature-impedance relationship model and an aging degree-impedance relationship model are constructed. The current line temperature and aging degree are obtained, and the temperature correction and aging correction per unit length impedance are obtained by substituting them into the models.

[0053] The initially calibrated unit length impedance is added to the temperature correction and aging correction to obtain the corrected unit length impedance.

[0054] The distance from the fault point to the circuit breaker is obtained by calculating the fault distance based on the fault circuit impedance and the corrected unit length impedance, thus determining the location of the fault point.

[0055] It should be noted that the impedance calculation model is a pre-established mathematical model based on the line fault type. Different fault types require different impedance calculation models. In one specific embodiment, a zero-sequence impedance model is used for single-phase-to-ground short circuits, a negative-sequence impedance model is used for phase-to-phase short circuits, and positive-sequence impedance is used directly for three-phase short circuits.

[0056] It should be noted that the correspondence between line parameters and impedance per unit length is obtained through theoretical calculations combined with experimental calibration. Based on the resistivity, cross-sectional area, and installation method of the conductor material, the theoretical value of impedance per unit length is calculated using formulas. Under standard conditions, the impedance values ​​of lines with different parameters are measured to establish a mapping table or empirical formula between parameters and impedance. The theoretical values ​​and measured data are integrated into a database or fitted curve for rapid matching in practical applications.

[0057] It should be noted that the method for constructing the line temperature-impedance relationship model is as follows: based on the line temperature and corresponding impedance values ​​recorded in historical operation, linear regression or curve fitting is used to obtain the nonlinear change of resistance with increasing temperature, and a model is constructed with line temperature as input and impedance as output.

[0058] It should be noted that the method for constructing the aging degree-impedance relationship model is as follows: based on historical long-term monitoring data or laboratory accelerated aging test data, the correlation between aging degree and impedance is fitted using linear regression or curve fitting, and a model is constructed with aging degree as input and impedance as output.

[0059] It should be noted that the fault distance is calculated by dividing the fault circuit impedance by the corrected unit length impedance.

[0060] It should be noted that the calculated fault distance is less than or equal to the total length from the circuit breaker to the end of the line, that is, the fault point is within the circuit breaker's line range. In this case, the calculated fault distance is the distance from the fault point to the circuit breaker.

[0061] In this embodiment, the present invention combines line temperature and aging degree to correct the impedance per unit length, thereby improving the accuracy of fault distance calculation. At the same time, by using the dual criteria of current flow direction and protection range, the selective nature of protection action is ensured, and false tripping due to faults outside the protection zone is avoided.

[0062] Furthermore, the specific process of determining whether the fault point is within the protection range of the circuit breaker in the protection action module is as follows:

[0063] The direction of current flow at the fault point is detected by a directional element.

[0064] Retrieve the protection range length of the circuit breaker stored in the database.

[0065] Determine if the fault point meets the following conditions:

[0066] (1) The current flow direction at the fault point is consistent with the direction of flow from the power supply side of the circuit breaker to the load side.

[0067] (2) The distance from the fault point to the circuit breaker is less than or equal to the protection range length of the circuit breaker.

[0068] If conditions (1) and (2) are met simultaneously, the fault point is determined to be within the protection range of the circuit breaker; otherwise, the fault point is determined to be outside the protection range of the circuit breaker.

[0069] In one specific embodiment, the direction of current flow at the fault point is detected by a power directional circuit breaker.

[0070] It should be noted that the current flow direction at the fault point is the same as the current flow direction from the power supply side of the circuit breaker to the load side, that is, the fault point is downstream of the circuit breaker.

[0071] It should be noted that if the fault point is outside the protection range of the circuit breaker, the adjacent circuit breaker will operate.

[0072] It should be noted that this invention uses a directional element to detect whether the fault current is consistent with a preset direction, and combines this with a determination based on whether the distance to the fault point is within the circuit breaker's setting range. Only when both conditions are met is the fault identified as within the protection zone and the protection action is triggered; otherwise, it is considered an external fault and no action is taken. This judgment logic effectively avoids the limitations of a single criterion and ensures the accuracy of the protection action.

[0073] It should be noted that this invention combines the dual criteria of current direction and fault distance, which can significantly improve the selectivity of protection and reduce the risk of false tripping, making it particularly suitable for complex operating conditions such as dual-ended power supply systems or high-resistance grounding. Furthermore, this method is highly compatible and can be adapted to various types of protection, including directional overcurrent and distance protection, improving reliability while optimizing the setting accuracy of the protection range.

[0074] Furthermore, the specific working process of selecting the current protection level in the protection action module is as follows:

[0075] Acquire line current and voltage data, identify data items that exceed the normal range, calculate the amount of each data item that exceeds the range as the over-limit quantity, and determine the maximum over-limit quantity as the electrical quantity over-limit quantity of the fault.

[0076] Based on the fault type and the electrical quantity exceeding the limit, and combined with the preset fault severity assessment rules, the severity of the fault is determined. The assessment rules are a quantitative mapping relationship between fault type, electrical quantity exceeding the limit range, and severity.

[0077] Based on the fault distance and the severity of the fault, the database is queried to find the fault distance and severity matching conditions corresponding to each current protection level, and the target current protection level is obtained by filtering.

[0078] In one specific embodiment, the current protection hierarchy includes instantaneous overcurrent protection, time-limited instantaneous overcurrent protection, and overcurrent protection. Instantaneous overcurrent protection is for severe faults occurring nearby, time-limited instantaneous overcurrent protection is for faults occurring at a medium distance, and overcurrent protection is for minor faults occurring at a distant location.

[0079] It should be noted that this invention dynamically determines the severity of the fault based on the excess electrical quantity and the fault type, so that the sensitivity of the protection action matches the actual harm of the fault.

[0080] It should be noted that by combining fault distance and fault severity, the present invention enables the system to select the most suitable current protection level, ensuring that the protection device prioritizes disconnecting the nearest fault point when a fault occurs, avoiding cascading tripping, and improving the reliability of power grid operation.

[0081] In this embodiment, the present invention matches the optimal protection level according to the fault distance and severity, avoids over-level tripping, shortens the disconnection time, improves the reliability of power grid operation, and reduces power outage losses.

[0082] The reclosing module sets an observation time window after tripping, monitors the line electrical parameters after tripping, and makes a preliminary judgment on the nature of the fault. If it is a transient fault, it performs a reclosing operation and verifies the judgment result based on the tripping situation after reclosing. If it is a permanent fault, it remeasures the line electrical parameters after a set interval to verify the nature of the fault. If it is verified to be a permanent fault, it blocks reclosing. If it is verified to be a misjudgment, it performs a reclosing operation.

[0083] Further, see Figure 2 As shown, the process for setting the observation time window in the reclosing module is as follows:

[0084] Based on historical fault data, the distribution of the duration of instantaneous faults, arc extinction duration, and voltage recovery duration is statistically analyzed, and their modes are calculated and denoted as reference duration, reference arc extinction duration, and reference voltage recovery duration.

[0085] The reference duration, the reference arc extinction duration, and the reference voltage recovery duration are compared, and the maximum value is taken as the expected duration of the observation time window.

[0086] The estimated duration of the observation time window is compared with the reclosing delay pre-stored in the database, and the smaller of the two values ​​is taken as the final duration of the observation time window.

[0087] Starting from the opening time, and combining it with the final duration of the observation time window, the closing time of the observation time window is determined.

[0088] It should be noted that the observation time window is longer than the instantaneous fault recovery time to improve the reliability of fault nature judgment. At the same time, the observation time window is shorter than the reclosing time to avoid the judgment not being completed before reclosing due to the window being too long.

[0089] Further, see Figure 3 As shown, the specific working process for initially determining the nature of a fault in the reclosing module is as follows: after the observation time window is closed, the electrical parameters of the line after the circuit breaker is tripped are monitored. If the line current drops to zero and the voltage recovers to the normal operating value after the circuit breaker is tripped, it is determined to be a transient fault; otherwise, it is determined to be a permanent fault.

[0090] Furthermore, the handling process for transient faults in the reclosing module is as follows:

[0091] When the fault is determined to be transient, a reclosing operation is performed.

[0092] Monitor the tripping situation after reclosing.

[0093] If no tripping occurs, the fault nature assessment is confirmed to be correct.

[0094] If a trip occurs, the fault is determined to be a permanent fault, the fault determination result is updated, and reclosing is blocked.

[0095] It should be noted that after initially identifying the fault as transient and executing reclosing, continuously monitoring the tripping situation to verify the judgment result can improve reliability and adaptive error correction. If the circuit does not trip after reclosing, it is directly confirmed that the fault has been eliminated, avoiding unnecessary blocking; if the circuit trips, it is corrected to a permanent fault to prevent repeated erroneous closing from damaging the equipment; and dynamically correcting the initial judgment error can ensure that the fault handling strategy matches the actual operating conditions, improving the system's fault tolerance.

[0096] Furthermore, the handling process for permanent faults in the reclosing module is as follows:

[0097] When a fault is determined to be permanent, the electrical parameters of the line are retested after a set interval.

[0098] If the retest result is consistent with the initial judgment, the fault is confirmed as a permanent fault and reclosing is blocked.

[0099] If the retest result is inconsistent with the initial judgment and meets the characteristics of a transient fault, the fault is determined to be a transient fault and a reclosing operation is performed.

[0100] It should be noted that after an initial diagnosis of a permanent fault, retesting electrical parameters at set intervals to verify the judgment result prevents misjudgment and improves fault tolerance, balancing safety and power supply continuity. Delayed retesting eliminates transient interference from momentary faults, avoiding erroneous blocking of the reclosing function due to initial misjudgment. Simultaneously, if the retested parameters return to the normal range, the judgment can be automatically corrected and reclosing executed, reducing the need for manual intervention. Furthermore, delayed retesting ensures accurate blocking of permanent faults while also providing an opportunity for line self-recovery, optimizing the robustness of fault handling strategies.

[0101] The information reporting module uploads fault information, tripping information, and reclosing information to the distribution network master station.

[0102] In this embodiment, the present invention dynamically sets the observation time window based on historical data and reclosing delay, and verifies the nature of the fault through retesting, thereby achieving accurate reclosing for instantaneous faults and reliable blocking for permanent faults, reducing equipment damage and power outage time.

[0103] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0104] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0105] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0106] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0107] Finally, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A primary and secondary integrated pole-mounted intelligent circuit breaker, characterized in that, include: Fault detection module: Real-time acquisition of current and voltage data of distribution network lines, fault judgment based on preset line fault judgment rules, and after identifying the fault, determining the fault type based on the characteristics of abnormal electrical quantities and executing protection action modules; Protection Action Module: Locates the fault point and determines whether the fault point is within the protection range of the circuit breaker based on the fault current flow direction. If it is within the protection range, the corresponding current protection level is selected according to the fault distance and severity, and the protection action is triggered to trip the circuit breaker; otherwise, the protection action is not triggered. Reclosing module: Sets an observation time window after tripping, monitors the electrical parameters of the line after tripping, and makes a preliminary judgment on the nature of the fault. If it is a transient fault, it performs a reclosing operation and verifies the judgment result based on the tripping situation after reclosing. If it is a permanent fault, it remeasures the electrical parameters of the line after a set interval to verify the nature of the fault. If it is verified to be a permanent fault, it blocks reclosing. If it is verified to be a misjudgment, it performs a reclosing operation. Information reporting module: Uploads fault information, tripping information, and reclosing information to the distribution network master station; The specific process for locating the fault point in the protection action module is as follows: Based on the type of line fault, the corresponding impedance calculation model is extracted from the database, and the impedance of the fault circuit is calculated by combining the electrical quantity data. Obtain line parameters, including conductor material, cross-sectional area, and erection method. Based on the preset correspondence between line parameters and impedance per unit length, determine the preliminary calibrated impedance per unit length. Based on historical impedance data, a line temperature-impedance relationship model and an aging degree-impedance relationship model are constructed. The current line temperature and aging degree are obtained, and the temperature correction and aging correction per unit length impedance are obtained by substituting them into the model. The initially calibrated unit length impedance is added to the temperature correction and aging correction to obtain the corrected unit length impedance. The distance from the fault point to the circuit breaker is obtained by calculating the fault distance based on the fault circuit impedance and the corrected unit length impedance, thus determining the location of the fault point.

2. The primary and secondary integrated pole-mounted intelligent circuit breaker according to claim 1, characterized in that: The specific working process of fault judgment in the fault detection module is as follows: The current and voltage data of the distribution network lines are collected in real time by current transformers and voltage transformers. The current data includes phase current and zero-sequence current, and the voltage data includes phase voltage, line voltage and zero-sequence voltage. The collected current and voltage data are compared with the corresponding normal ranges stored in the database; When any current or voltage data exceeds its normal range, an abnormal signal is generated and timing is started. If the duration of the abnormal signal exceeds a preset duration threshold, it is determined that a fault has occurred in the power distribution network line.

3. The primary and secondary integrated pole-mounted intelligent circuit breaker according to claim 1, characterized in that: The specific process for determining the fault type in the fault detection module is as follows: Based on the current and voltage data of the line, electrical quantity data is extracted from them, including three-phase voltage, three-phase current, zero-sequence component and negative-sequence component; The electrical quantity data is compared with the abnormal electrical quantity characteristics corresponding to each preset fault type, wherein the abnormal electrical quantity characteristics include voltage characteristics and current characteristics; If the electrical quantity data completely matches at least one of the abnormal voltage characteristics and abnormal current characteristics corresponding to a certain fault type, then the line fault type is determined to be that fault type. If no perfectly matching fault type exists, count the number of consistent feature items in the abnormal electrical quantity characteristics corresponding to each fault type from the electrical quantity data. Then, perform a weighted summation of each consistent feature item according to a preset weight to obtain the matching degree of each fault type. The fault type with the highest matching degree is taken as the line fault type.

4. The primary and secondary integrated pole-mounted intelligent circuit breaker according to claim 1, characterized in that: The specific process by which the protection action module determines whether the fault point is within the protection range of the circuit breaker is as follows: The direction of current flow at the fault point is detected by a directional element; Retrieve the protection range length of the circuit breaker stored in the database; Determine if the fault point meets the following conditions: (1) The current flow direction at the fault point is consistent with the direction of flow from the power supply side of the circuit breaker to the load side; (2) The distance from the fault point to the circuit breaker is less than or equal to the length of the protection range of the circuit breaker; If conditions (1) and (2) are met simultaneously, the fault point is determined to be within the protection range of the circuit breaker; otherwise, the fault point is determined to be outside the protection range of the circuit breaker.

5. The primary and secondary integrated pole-mounted intelligent circuit breaker according to claim 1, characterized in that: The specific working process of selecting the current protection level in the protection action module is as follows: Acquire line current and voltage data, identify data items that exceed the normal range, calculate the amount of each data item that exceeds the range as the over-limit quantity, and determine the maximum over-limit quantity as the electrical quantity over-limit quantity of the fault. Based on the fault type and the electrical quantity exceeding the limit of the fault, and in conjunction with the preset fault severity assessment rules, the severity of the fault is determined, wherein the assessment rules are a quantitative mapping relationship between fault type, electrical quantity exceeding the limit range and severity. Based on the fault distance and the severity of the fault, the database is queried to find the fault distance and severity matching conditions corresponding to each current protection level, and the target current protection level is obtained by filtering.

6. The primary and secondary integrated pole-mounted intelligent circuit breaker according to claim 1, characterized in that: The process for setting the observation time window in the reclosing module is as follows: Based on historical fault data, the distribution of the duration of instantaneous faults, arc extinction duration, and voltage recovery duration is statistically analyzed, and their modes are calculated and denoted as reference duration, reference arc extinction duration, and reference voltage recovery duration. The reference duration, the reference arc extinction duration, and the reference voltage recovery duration are compared, and the maximum value is taken as the expected duration of the observation time window. The estimated duration of the observation time window is compared with the reclosing delay pre-stored in the database, and the smaller of the two values ​​is taken as the final duration of the observation time window. Starting from the opening time, and combining it with the final duration of the observation time window, the closing time of the observation time window is determined.

7. The primary and secondary integrated pole-mounted intelligent circuit breaker according to claim 1, characterized in that: The specific working process for initially determining the nature of a fault in the reclosing module is as follows: After the observation time window is closed, monitor the electrical parameters of the line after the circuit breaker is tripped. If the line current drops to zero and the voltage returns to the normal operating value after the circuit breaker is tripped, it is determined to be a transient fault; otherwise, it is determined to be a permanent fault.

8. The primary and secondary integrated pole-mounted intelligent circuit breaker according to claim 1, characterized in that: The handling process for transient faults in the reclosing module is as follows: When the fault is determined to be transient, a reclosing operation is performed; Monitor the tripping status after reclosing; If no tripping occurs, the fault nature assessment is confirmed to be correct; If a trip occurs, the fault is determined to be a permanent fault, the fault determination result is updated, and reclosing is blocked.

9. A primary and secondary integrated pole-mounted intelligent circuit breaker according to claim 1, characterized in that: The process for handling permanent faults in the reclosing module is as follows: When the fault is determined to be a permanent fault, the electrical parameters of the line are retested after a set interval. If the retest result is consistent with the initial judgment, the fault is confirmed as a permanent fault and reclosing is blocked. If the retest result is inconsistent with the initial judgment and meets the characteristics of a transient fault, the fault is determined to be a transient fault and a reclosing operation is performed.

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