Power distribution network operation state intelligent monitoring method based on wireless communication network

Abstract

The invention relates to the technical field of power distribution network operation monitoring, in particular to a power distribution network operation state intelligent monitoring method based on a wireless communication network. According to the invention, a mode of combining cloud pre-generation of a plan and edge local matching execution is adopted; that is to say, the cloud platform generates a disposal plan package for an identified high-risk target in advance and issues the disposal plan package to the edge gateway; when a fault occurs, the edge gateway can quickly match and activate execution from a plurality of processing plans stored locally without waiting for a cloud instruction, so that the fault response speed is improved, the fault isolation and recovery time is shortened, and the problem of slow response caused by communication delay in the prior art is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of power distribution network operation monitoring technology, and specifically to a method for intelligent monitoring of power distribution network operation status based on wireless communication networks. Background Technology

[0002] With the large-scale integration of renewable energy and the continuous increase in urban load density, the operation of power distribution networks is becoming increasingly complex, placing higher demands on power supply reliability and self-recovery capabilities. When a fault occurs in the power distribution network, it is necessary to quickly and accurately isolate the faulty section and restore power supply to the non-faulty sections to improve power supply reliability.

[0003] Existing technologies, such as Chinese invention patent publication number CN104967123B, disclose a monitoring device and method for intermittent energy consumption in a power distribution network. It adopts an architecture that coordinates a back-end server and a measurement and control unit. The back-end server makes global optimization decisions based on an intelligent expert database and sends adjustment commands to the field measurement and control unit for execution via a wireless network, focusing on the optimized scheduling and consumption of distributed power sources. However, its fault handling relies on centralized decision-making in the cloud and remote real-time command issuance. When the communication network has high latency, instability, or even interruption, the system response speed will be constrained, making it difficult to meet the needs for rapid isolation and recovery from transient faults.

[0004] For example, Chinese invention patent CN119298367A discloses a resilient recovery management system for urban power distribution networks under extreme weather conditions. This system uses edge computing units for local data processing and real-time optimization, and can execute power path switching according to strategies. While improving local response capabilities, the decision-making logic of the edge computing unit tends to be based on dynamic calculations and adjustments using real-time data, lacking predefined and structured contingency plans for known high-risk scenarios. When facing complex multi-branch faults or communication interruptions, its reliance on real-time calculation to generate strategies may result in decision-making delays, and it also lacks the ability to autonomously generate effective alternative power restoration paths based on local network topology and real-time operational status data. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art, solve the problems of over-reliance on centralized decision-making and stable communication lines in fault handling, lack of local multi-plan storage and autonomous matching capabilities at the edge, and inability to autonomously generate alternative power restoration paths based on real-time operating status data when communication is interrupted.

[0006] The technical solution adopted by the present invention to solve its technical problem is: a method for intelligent monitoring of the operation status of distribution network based on wireless communication network, including the following steps: S1, the cloud platform identifies high-risk targets based on the operation data of the entire distribution network, and generates a disposal plan package for each high-risk target and sends it to the corresponding edge gateway for storage.

[0007] S2. The edge gateway monitors the real-time distribution network operation data of the lines under its jurisdiction. When the fault triggering conditions are met, it automatically matches and activates one from the local emergency response plan package.

[0008] S3. The edge gateway sends control commands to the segment switches in the predefined switch operation sequence based on the activated contingency plan package to isolate the faulty segment.

[0009] S4. After isolating the faulty section, the edge gateway sends a closing command to the tie switch in the pre-planned power switching path to restore power supply to the non-faulty section.

[0010] S5. During the execution of steps S1 to S4, the edge gateway determines whether to autonomously generate and execute an alternative power supply restoration path based on the local network topology and the real-time total active load value, according to the real-time operating status data.

[0011] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention adopts a combination of cloud-based pre-generated contingency plans and edge-based local matching and execution; that is, the cloud platform generates a contingency plan package for the identified high-risk targets in advance and sends it to the edge gateway; when a fault occurs, the edge gateway does not need to wait for cloud instructions, and can quickly match and activate the execution from multiple contingency plans stored locally, thereby improving the fault response speed and shortening the fault isolation and recovery time, effectively overcoming the slow response problem caused by communication delay in the prior art.

[0012] 2. In this invention, the edge gateway can autonomously traverse, evaluate, and execute the optimal alternative power supply recovery path when the pre-planned power switching path fails or communication is interrupted. By constructing multi-level recovery safeguards, the power supply reliability of the distribution network under complex operating conditions or communication failures is improved.

[0013] 3. The emergency response plan package of the present invention includes fault boundaries, tripping objects, pre-planned power switching paths, fault triggering condition sets, execution constraint parameter sets, autonomous decision flags, and corresponding high-risk targets. When a fault occurs, the edge gateway executes based on the emergency response plan package, reducing the time and resource consumption required for real-time calculation on-site, thereby improving the timeliness and execution efficiency of fault response in communication-constrained scenarios. Attached Figure Description

[0014] 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.

[0015] Figure 1This is a schematic diagram of the monitoring method of the present invention.

[0016] Figure 2 This is a schematic diagram of the process for identifying high-risk targets according to the present invention.

[0017] Figure 3 This is a schematic diagram illustrating the process of generating a contingency plan package according to the present invention.

[0018] Figure 4 This is a schematic diagram of the process for isolating faulty sections according to the present invention. Detailed Implementation

[0019] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. Furthermore, it should be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale.

[0020] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification.

[0021] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0023] The specific scheme of the intelligent monitoring method for the operation status of distribution networks based on wireless communication networks provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0024] Please see Figure 1 The document shows a flowchart of the intelligent monitoring method for the operation status of a distribution network based on a wireless communication network provided by the present invention, which specifically includes the following steps: Step S1: The cloud platform identifies high-risk targets based on the operation data of the entire distribution network, and generates a disposal plan package for each high-risk target and sends it to the corresponding edge gateway for storage.

[0025] The cloud platform and the edge gateway interact with each other via wireless communication networks, such as 4G / 5G or dedicated power IoT networks.

[0026] Step S10: First, the cloud platform needs to acquire operational data covering the entire power distribution network as the basic input for identifying high-risk targets.

[0027] The power distribution network operation data includes the three-phase current, three-phase voltage, and total active power of the lines; real-time temperature of key equipment points; active power injected by distributed power sources; and real-time total active load value used to characterize the power grid load status.

[0028] Distribution network operation data is collected and uploaded by smart terminals deployed at line nodes. The smart terminals include at least feeder terminal units, distribution transformer monitoring terminals, or smart meters with electrical parameter metering functions, capable of collecting three-phase voltage, three-phase current, and active power in real time.

[0029] Key equipment points mainly refer to areas in the power distribution network prone to thermal failures or mechanical stress concentrations; for example, cable joints, sectionalizing switch contacts, and tie switch terminals. The temperature of these key points can be monitored using infrared thermal imagers or built-in sensors.

[0030] The active power injected by distributed power sources refers to the actual power transmitted to the distribution network when distributed energy sources such as photovoltaics and wind turbines are connected to the grid, which is provided through dedicated metering devices for distributed energy sources.

[0031] The real-time total active load value used to characterize the power grid load status specifically refers to the net value of the sum of the loads of all users downstream of the currently monitored line section minus the active power injected by distributed generation. It reflects the net load that actually needs to be borne by the main grid or transfer lines.

[0032] Please see Figure 2 Step S11: The cloud platform identifies high-risk targets based on the full distribution network operation data. The specific process is as follows: calculate the ratio of the total active power of the line to the rated active capacity as the load factor.

[0033] Here, rated active capacity refers to the upper limit of active power that the line is allowed to transmit stably over a long period of time. It is determined as follows: based on the conductor type, cross-sectional area, and laying method of the line, and according to the national conductor current-carrying capacity standard, the rated apparent capacity of the line is found; then, the rated apparent capacity is multiplied by a preset reference power factor to obtain the rated active capacity. The reference power factor is set according to the distribution network planning specifications, and typically ranges from 0.85 to 0.95; in this invention, it can be exemplarily set to 0.9.

[0034] The relative temperature rise is calculated based on the real-time temperature and the ambient reference temperature; the ambient reference temperature can be obtained from a temperature and humidity sensor installed outside the power distribution room.

[0035] The unbalance is calculated as the percentage of the range of the three-phase currents relative to their average value.

[0036] A Fast Fourier Transform (FFT) is performed on the acquired three-phase voltage signal to convert the time-domain voltage signal into a frequency-domain spectrum, thereby separating the fundamental component and the harmonic components of each integer harmonic multiple. The spectral amplitude corresponding to the fundamental component is divided by... The effective value of the fundamental voltage can then be obtained.

[0037] The total harmonic distortion rate is obtained by comparing the root mean square of the effective values ​​of all harmonic component voltages with the effective value of the fundamental component.

[0038] The output ratio is obtained by comparing the active power injected by the distributed generation source with the total active power of the line; the load fluctuation rate is calculated based on the change of the total active load value within the statistical period.

[0039] The statistical period is typically set to 5-15 minutes. If the statistical period is too short, the calculation results are easily affected by random disturbances and have poor stability; if the statistical period is too long, valuable fluctuation information may be smoothed out, leading to a lag in early warning of high-risk source-load mismatch. To balance response speed and data stability, a 10-minute period is used as an example in this invention.

[0040] After obtaining the load factor, relative temperature rise, imbalance, total harmonic distortion rate, and load fluctuation rate, the determination should be made based on the changing trends and amplitudes of these parameters over multiple consecutive sampling periods.

[0041] It should be noted that in this invention, the number of consecutive sampling periods is 3-5, and 4 is an example. Too few sampling periods may be affected by random fluctuations, while too many sampling periods will lead to response delays.

[0042] If all of the following conditions are met simultaneously: the load rate and relative temperature rise are both greater than the values ​​of the previous sampling period in each sampling period, and the overall slope of change exceeds the set baseline slope, meaning both are continuously rising. Simultaneously, the maximum absolute value of the difference between adjacent values ​​of the imbalance and load rate within consecutive sampling periods is calculated and compared. The comparison result shows that the change in imbalance is less than the change in load rate.

[0043] If the load and temperature rise increase simultaneously, it is considered a high-risk overload. This is because the typical characteristic of equipment overload is that the load and temperature rise increase simultaneously. Although three-phase imbalance may also cause local overheating, if the change is not obvious, it helps to rule out the temperature rise caused by simple uneven load, thus more accurately pointing to the overall overload risk.

[0044] The baseline slope can be determined based on historical data statistics. For example, at least 30 days of historical load rate data under normal operating conditions can be selected, and the standard deviation σ of its variation in adjacent sampling periods can be calculated. The baseline slope can be set as k×σ, where k is the confidence coefficient, typically between 2 and 3, a range that statistically covers 95% to 99.7% of normal fluctuations. In this invention, 2.5 can be used as an example.

[0045] Based on the above process of judging the continuous upward trend by the overall change slope and the calculation process of the change range, the following analysis is also conducted.

[0046] If the output share continues to rise for 1-2 sampling periods, and the total harmonic distortion (THD) rate also continues to rise, while the load rate change is less than the THD change, then it is classified as a high-risk distributed generation disturbance. This is because an increase in distributed generation output may lead to an increase in grid harmonic content. If the harmonic increase exceeds the load change, it is very likely caused by a power source disturbance.

[0047] Since the impact of distributed power generation output changes on grid harmonics usually has a short delay, 1-2 sampling periods are selected.

[0048] If the load volatility and the output ratio continue to change in opposite directions, specifically, if in multiple consecutive sampling periods the load volatility continues to rise while the output ratio continues to fall, or the load volatility continues to fall while the output ratio continues to rise; and if the change in load volatility is greater than the change in output ratio, then it is judged as a high-risk source-load mismatch.

[0049] High-risk source-load mismatch reflects that the regulation capability of distributed power sources has failed to match the rapid changes in load, which may lead to three-phase voltage exceeding limits.

[0050] Otherwise, it is determined that no high-risk target has been identified. Ultimately, any monitoring target exhibiting any of the high-risk characteristics will be identified as a high-risk target.

[0051] Please see Figure 3 After identifying high-risk targets in step S12, it is also necessary to generate a contingency plan package in advance to enable the edge gateway to respond quickly when the risk evolves into a failure, thus shortening the power outage time.

[0052] The specific process for generating the emergency response plan is as follows: First, the electrical range between the upstream and downstream adjacent sectionalizing switches of the line section where the high-risk target is located is defined as the fault boundary.

[0053] Among them, a sectionalizing switch refers to a circuit breaker or load switch installed on a line to isolate a faulty section. It is the most direct actuator for achieving fault isolation, therefore, the upstream and downstream sectionalizing switches adjacent to each other on both sides of the fault boundary are considered as the objects of tripping. The electrical range refers to the electrical connection area formed by all connected lines and equipment between two sectionalizing switches.

[0054] Then, starting from the tie switch electrically connected to the line section, the difference between the rated transmission capacity of each adjacent feeder and its current total active load value is calculated as the available transfer capacity.

[0055] The current total active load value refers to the value obtained at the moment the contingency plan package is generated on the cloud platform. The rated transmission capacity of each adjacent feeder refers to the upper limit of active power that the adjacent feeder, which serves as a backup power source, is allowed to transmit stably over a long period of time. Its determination method is the same as that of the rated active capacity.

[0056] It should be noted that a tie switch is a normally open switch that connects different feeders to enable load transfer in the event of a fault. Adjacent feeders refer to other power supply lines electrically connected through a tie switch.

[0057] Next, since the upstream section of the fault boundary is usually still powered by the main power source, such as a substation, its restoration is not the responsibility of the tie switch. Therefore, the main task is to restore power to the downstream non-faulty section. This requires comparing the available transfer capacity with the current total active load of the downstream non-faulty section of the fault boundary.

[0058] If the available transfer capacity is not less than the current total active load value of the non-faulty section downstream of the fault boundary, then the corresponding tie switch and adjacent feeder path, that is, the complete electrical path from the tie switch through the adjacent feeder to the transfer load, will be used as the pre-planned power switching path.

[0059] Simultaneously, the criteria for identifying high-risk targets are used as the fault triggering condition set. Operations personnel configure a set of execution constraint parameters on the cloud platform to define the selective shelving of loads in non-faulty sections downstream of the fault boundary. This set of execution constraint parameters is typically determined based on distribution network dispatching procedures and user contracts.

[0060] The set of execution constraint parameters includes: grid conditions that define the initiation of load shedding; for example, voltage below 0.9 times the rated voltage for 10 seconds.

[0061] The order in which power is cut off to ensure the priority of critical loads; for example, according to a load priority list.

[0062] Total load limits are used to prevent over-cutting; for example, not exceeding 30% of the total load of the non-faulty section downstream of the fault boundary.

[0063] Furthermore, an autonomous decision-making flag must be configured to authorize the edge gateway to generate alternative power restoration paths. For example, if line failures are frequent or the location is in an area with unstable communication, this flag should be set to enabled, authorizing the edge gateway to autonomously decide and generate alternative power restoration paths. Otherwise, it should be set to disabled.

[0064] It should be noted that the specific configuration logic of the autonomous decision flag is mainly based on a comprehensive judgment of the historical fault frequency of the line, the stability of regional communication, and the importance level of the load. It can be implemented using mature strategy configuration methods in the existing technology, and will not be elaborated on in this invention.

[0065] Ultimately, the fault boundary, tripping object, pre-planned power switching path, fault triggering condition set, execution constraint parameter set, autonomous decision flag and corresponding high-risk target are integrated to form a contingency plan package.

[0066] Step S13: After completing the overall construction of the emergency response plan package, in order to ensure the reliability and controllable sequence of subsequent isolation operations, it is necessary to further determine the operation sequence of the switches to form a predefined switch operation sequence.

[0067] The specific determination process is as follows: when the emergency response plan package is generated, if the fault boundary is only associated with one sectionalizing switch, considering that a single-end power supply line only needs to disconnect the fault-side switch to isolate it, a tripping command is generated pointing to that sectionalizing switch.

[0068] If two sectionalizing switches are connected, upstream and downstream, two tripping commands will be generated in the order of upstream first, then downstream. Tripping the upstream first prevents fault current backflow and ensures the safety of downstream operators; tripping the downstream later ensures complete isolation.

[0069] If any sectionalizing switch has no directly adjacent backup switch of the same level, after generating a tripping command for the target sectionalizing switch, an additional tripping command is attached, pointing to the upstream sectionalizing switch or to the adjacent feeder power supply switch supplying power to the downstream non-faulty section, as a backup command. This improves the reliability of isolation operations and avoids isolation failure due to a single switch refusing to operate.

[0070] Finally, the segmented switch identifier, instruction type, and execution order are combined to form a predefined switch operation sequence and stored in the contingency plan package.

[0071] The sectionalizing switch identifier is uniformly coded by the distribution network automation system. The instruction type is either the aforementioned tripping instruction or backup tripping instruction.

[0072] After the cloud platform generates the emergency response plan package, it distributes it to the edge gateway storage in the corresponding region.

[0073] Step S2: The edge gateway monitors the real-time distribution network operation data of the lines under its jurisdiction, and automatically matches and activates one from the local emergency response plan package when the fault triggering conditions are met.

[0074] The reason why high-risk targets are first identified by the cloud platform and emergency response plans are issued, followed by monitoring by the edge gateway, is that the cloud platform has a global view and powerful computing capabilities, making it suitable for global and complex risk analysis; while the edge gateway is deployed on-site, responds quickly, and is suitable for performing localized real-time monitoring and rapid control. The collaboration between the two can achieve a balance between efficiency and speed.

[0075] Specifically, the edge gateway continuously collects and caches real-time power distribution network operation data for multiple consecutive sampling periods of the lines under its jurisdiction.

[0076] Calculate the load rate, relative temperature rise, unbalance, total harmonic distortion, output ratio, and load fluctuation rate for each sampling period.

[0077] Based on the changing trends and magnitudes of each parameter over multiple consecutive sampling periods, determine whether the criteria for identifying high-risk targets in any contingency plan package are met. If met, immediately activate the contingency plan package and execute step S3 below. If not met, the edge gateway continues monitoring.

[0078] Please see Figure 4 In step S3, the edge gateway sends control commands to the segment switches in the predefined switch operation sequence based on the activated contingency plan package to isolate the faulty segment.

[0079] The specific process is as follows: After the edge gateway activates the emergency response plan package, it parses the tripping objects within it and sends tripping commands to the sectionalizing switches in sequence according to the predefined switch operation sequence.

[0080] After each tripping command is sent, if a tripping confirmation signal from the target sectionalizing switch is received within the preset response time, the tripping is considered successful and execution continues. This ensures that the tripping command is effectively executed and avoids false tripping.

[0081] The trip confirmation signal is issued by the controller of the sectionalizing switch body after successfully performing the trip operation. It is usually a status feedback signal used to determine that the switch has actually been operated.

[0082] Since the opening time of modern vacuum circuit breakers is typically less than or equal to 60ms, and considering the round-trip delay of communication and signal processing time, the preset response time is usually set to 2-5 seconds to ensure that an acknowledgment signal is received in most cases. In this invention, 3 seconds can be used as an example; if the communication quality is poor or the sectionalizing switch is old, it can be increased to 5 seconds; if the sectionalizing switch is a high-speed solid-state switch, it can be reduced to 2 seconds.

[0083] Otherwise, the tripping failure is determined, and the backup command corresponding to the target sectionalizing switch is executed; if there is no backup command, a tripping command is sent to the upstream or downstream adjacent sectionalizing switch of the target sectionalizing switch. In this way, through multi-layered isolation protection, the success of isolation is guaranteed to the greatest extent and the fault is prevented from spreading.

[0084] Until the sectionalizing switches on both sides of the fault boundary are successfully tripped, and the voltage and current of each of the three phases in the fault section drop to the preset isolation safety range, ensuring that the fault point has been completely de-energized and there is no risk of arc reignition, the electrical isolation of the fault section is then completed.

[0085] According to safety regulations and experience in the power industry, to ensure complete electrical isolation of the fault point, the voltage and current at the fault point must be reduced to a very low level after isolation. Typically, the three-phase voltage must be 10% lower than the rated voltage, and the three-phase current must be 5% lower than the rated current.

[0086] Specifically, the preset isolation safety range is defined as follows: the three-phase voltage is in the range [0, 10% of the rated voltage], and the three-phase current is in the range [0, 5% of the rated current].

[0087] After electrical isolation of the faulty section is completed, proceed to step S4 according to the power distribution network safety operation procedures. This prevents backfeeding to the fault point, ensuring personal and equipment safety and thorough fault isolation.

[0088] Step S4: After isolating the faulty section, the edge gateway sends a closing command to the tie switch in the pre-planned power switching path to restore power supply to the non-faulty section.

[0089] The specific process is as follows: After the electrical isolation of the faulty section is completed, the edge gateway parses the pre-planned power switching path in the corresponding contingency plan package and obtains the identifier of the target interconnection switch and its feeder.

[0090] Then, a pre-closing verification is performed on the target interconnection switch to ensure the safety and feasibility of the closing operation and to avoid secondary failures caused by misoperation.

[0091] The specific verification process is as follows: confirm that the sectionalizing switches on both sides of the fault boundary have been opened to prevent the circuit from being closed and forming a loop when the fault point is not isolated, which could cause a short circuit or expand the fault; based on the real-time data collected by the edge gateway, calculate the available transfer capacity of the target power supply feeder and determine whether it is not less than the current total active load value of the non-faulty section downstream of the fault boundary, so as to prevent the new power supply line from causing a new overload fault due to excessive load after the transfer.

[0092] If all the above conditions are met, the verification is deemed successful and a closing command is sent; otherwise, the verification is deemed unsuccessful, and the closing operation will not be performed and step S5 will be triggered.

[0093] After sending the closing command, if a closing confirmation signal from the target interconnecting switch is received within the preset response time, and the three-phase voltage and three-phase current of the restored power supply line are restored to the preset safe operating range, then the power supply restoration is determined to be successful; otherwise, the power supply restoration is determined to be unsuccessful and step S5 is executed.

[0094] The closing confirmation signal is issued by the controller of the tie switch body after the closing operation is successfully executed.

[0095] According to national standards, the voltage deviation limit for three-phase voltages of 20kV and below is ±7% of the rated voltage. However, considering the line voltage drop and actual engineering margin, the safe operating range is often set to 0.9-1.1 times the rated voltage; therefore, the three-phase voltage portion of the preset safe operating range here is set to [0.9 times the rated voltage, 1.1 times the rated voltage].

[0096] For three-phase current, its safe operating limit is usually defined by the overcurrent setting of the line. Therefore, the three-phase current portion of the preset safe operating range is set to [0, overcurrent setting]; the overcurrent setting is obtained according to the protection setting sheet of the specific line, and is usually set to 1.2 times the rated current of the line.

[0097] Step S5: During the execution of steps S1 to S4, the edge gateway determines whether to autonomously generate and execute an alternative power supply restoration path based on the local network topology and the real-time total active load value, according to the real-time operating status data.

[0098] During the execution of steps S1 to S4, if any of the following conditions are detected: a. Electrical isolation is not completed.

[0099] b. Power restoration failed.

[0100] C. After power is restored, the effective value of the three-phase current of the line continues to exceed its overcurrent setting or the effective value of the three-phase voltage continues to be lower than its undervoltage setting.

[0101] This indicates that the power restoration operation based on the pre-planned power switching path failed to be executed successfully, or the power quality after execution did not meet the requirements, posing a risk of power outage or operation failure.

[0102] The undervoltage setting is typically set to 85% of the rated voltage according to national standards; "continuously exceeding" and "continuously falling below" refer to a duration of more than 1 second to avoid short-term fluctuations.

[0103] At this point, the edge gateway checks whether the autonomous decision-making flag is enabled in the currently active contingency plan package. If the autonomous decision-making flag is not enabled, autonomous recovery is stopped and the issue is reported to the power distribution network operation monitoring cloud platform for remote handling by maintenance personnel.

[0104] If the autonomous decision flag is enabled, then based on the local network topology, i.e. the electrical connection diagram of the area under the jurisdiction of the edge gateway, and the real-time total active load value, it traverses all interconnecting switches and adjacent feeders that are electrically connected to the non-faulty section downstream of the fault boundary.

[0105] Then, calculate the available transfer capacity of each adjacent feeder. If it is not less than the current total active load value of the non-faulty section downstream of the fault boundary, then the corresponding tie switch and adjacent feeder path are selected as candidate paths. Ensure that the candidate paths have power supply capacity and avoid invalid attempts.

[0106] Next, the candidate paths are sorted in descending order of available transfer capacity, and the first one is selected as the alternative power restoration path.

[0107] Subsequently, a closing command is sent to the tie switch in the alternative power supply restoration path. If a closing confirmation signal is received within the preset response time, and the three-phase voltage and three-phase current in the non-faulty section are restored to the preset safe operating range, then the alternative power supply restoration is successful.

[0108] If the alternative power supply restoration path generation fails or the alternative power supply restoration fails, and any of the preset termination conditions are met, then the autonomous restoration will stop and the cloud platform will be reported.

[0109] After each failed attempt, the edge gateway marks the corresponding communication switch as temporarily unavailable and excludes it from the current candidate path set.

[0110] The preset termination conditions include: the number of autonomous attempts is greater than or equal to 3; the total processing time exceeds 60 seconds from the first activation of the contingency plan package; and all candidate paths are unavailable.

[0111] It should be noted that, typically, three autonomous attempts are sufficient to cover the main alternatives within a limited number of candidate paths, avoiding getting stuck in meaningless loops. The total processing time of 60 seconds takes into account the timeliness requirements of distribution network fault recovery; excessively long autonomous recovery attempts may affect the overall stability of the system.

[0112] If the current alternative power supply recovery path generation fails or the alternative power supply recovery fails, but none of the preset termination conditions are met, the edge gateway will reorder the remaining paths in descending order of available transfer capacity and select the first one as a new alternative power supply recovery path to try.

[0113] In a preferred embodiment of the present invention, a 2-second wait is performed after each failed attempt to allow the power grid transient process to decay and the switching mechanism to reset. The 2-second wait time is chosen based on the following considerations: a wait time that is too short may lead to hasty attempts before the power grid condition has stabilized, easily resulting in further failures. A wait time that is too long will unnecessarily prolong the power outage time in non-faulty areas, reducing power supply reliability.

[0114] 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.

[0115] 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 implementations should not be considered beyond the scope of this invention.

[0116] In addition, the functional modules in the various embodiments of the present invention 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.

[0117] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

[0118] 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 method for intelligent monitoring of distribution network operation status based on wireless communication networks, characterized in that, include: S1. The cloud platform identifies high-risk targets based on the operation data of the entire power distribution network and generates a response plan package for each high-risk target, which is then sent to the corresponding edge gateway for storage. S2. The edge gateway monitors the real-time distribution network operation data of the lines under its jurisdiction, and automatically matches and activates one from the local emergency response plan package when the fault triggering conditions are met. S3. The edge gateway sends control commands to the segment switches in the predefined switch operation sequence based on the activated contingency plan package to isolate the faulty segment. S4. After isolating the faulty section, the edge gateway sends a closing command to the tie switch in the pre-planned power switching path to restore power supply to the non-faulty section. S5. During the execution of steps S1 to S4, the edge gateway determines whether to autonomously generate and execute an alternative power supply restoration path based on the local network topology and the real-time total active load value, according to the real-time operating status data.

2. The intelligent monitoring method for distribution network operation status based on wireless communication network according to claim 1, characterized in that, The power distribution network operation data includes: three-phase current, three-phase voltage, and total active power of the lines; real-time temperature of key equipment points; active power injected by distributed power sources; and real-time total active load value used to characterize the power grid load status.

3. The intelligent monitoring method for distribution network operation status based on wireless communication network according to claim 2, characterized in that, The process for identifying high-risk targets is as follows: The ratio of the total active power of the line to the rated active capacity is used as the load factor; the relative temperature rise is calculated based on the real-time temperature and the ambient reference temperature; the percentage of the range and average value of the three-phase current is used as the unbalance. Spectral analysis of the three-phase voltage is performed, and the root mean square of the effective values ​​of all harmonic components is calculated and compared with the effective value of the fundamental component to obtain the total harmonic distortion rate. The output ratio is obtained by comparing the active power injected by the distributed generation with the total active power of the line; the load fluctuation rate is calculated based on the change of the total active load value within the statistical period. Based on multiple consecutive sampling periods, if both the load rate and relative temperature rise continue to increase, and the change in imbalance is less than the change in load rate, it is judged as a high-risk overload. If the total harmonic distortion rate continues to rise after the output ratio continues to rise, and the change in load rate is less than the change in total harmonic distortion rate, then it is judged as a high-risk distributed power source disturbance. If the load volatility and the output ratio continue to change in opposite directions, and the change in load volatility is greater than the change in output ratio, then it is judged as a high-risk source-load mismatch. Any monitoring target exhibiting any of the high-risk characteristics will be identified as a high-risk target.

4. The intelligent monitoring method for distribution network operation status based on wireless communication network according to claim 2, characterized in that, The process of generating the emergency response plan package is as follows: The electrical range between the upstream and downstream adjacent sectionalizing switches of the line section where the high-risk target is located is defined as the fault boundary; The upstream and downstream sectionalizing switches adjacent to each other on both sides of the fault boundary are taken as the tripping objects; Starting from the tie switch electrically connected to the line section, calculate the difference between the rated transmission capacity of each adjacent feeder and its current total active load value, which is taken as the available transfer capacity; If the available transfer capacity is not less than the current total active load of the non-faulty section downstream of the fault boundary, then the corresponding tie switch and adjacent feeder path will be used as the pre-planned power switching path. The criteria for identifying high-risk targets are used as the set of fault triggering conditions; Configure the set of execution constraint parameters used to define the selective shedding of downstream loads; Configure an autonomous decision flag for authorizing edge gateways to generate alternative power restoration paths; The fault boundary, the tripping object, the pre-planned power switching path, the fault triggering condition set, the execution constraint parameter set, the autonomous decision flag and the corresponding high-risk target are integrated to form a contingency plan package.

5. The intelligent monitoring method for distribution network operation status based on wireless communication network according to claim 4, characterized in that, The process for determining the predefined switch operation sequence is as follows: If the fault boundary is associated with only one sectionalizing switch, a trip command is generated for that sectionalizing switch; if it is associated with two sectionalizing switches, upstream and downstream, two trip commands are generated in the order of upstream first and then downstream. If any sectionalizing switch does not have a directly adjacent backup switch of the same level, then an additional tripping instruction is added, pointing to the sectionalizing switch above it, or to the adjacent feeder power supply side switch that supplies power to the downstream non-faulty section, as a backup instruction. The segmented switch identifier, instruction type, and execution order are combined to form a predefined switch operation sequence, which is then stored in the contingency plan package.

6. The intelligent monitoring method for distribution network operation status based on wireless communication network according to claim 3, characterized in that, Step S2 specifically involves: The edge gateway continuously collects and caches real-time power distribution network operation data for multiple consecutive sampling cycles of the lines under its jurisdiction; Calculate the load rate, relative temperature rise, unbalance, total harmonic distortion, output ratio, and load fluctuation rate for each sampling period; Based on the changing trends and magnitudes of each parameter over multiple consecutive sampling periods, determine whether the judgment conditions in any emergency response package are met. If the conditions are met, the contingency plan package will be activated immediately.

7. The intelligent monitoring method for distribution network operation status based on wireless communication network according to claim 1, characterized in that, Step S3 specifically involves: After the edge gateway activates the emergency response plan package, it parses the tripping objects within it and sends tripping commands to the sectionalizing switches sequentially according to the predefined switch operation sequence. If a trip confirmation signal is received within the preset response time after each trip command is sent, the trip is considered successful and execution continues. Otherwise, the tripping failure is determined and the backup instruction corresponding to the target sectionalizing switch is executed; if there is no backup instruction, the tripping instruction is sent to the upstream or downstream adjacent sectionalizing switch of the target sectionalizing switch. The electrical isolation of the fault section is completed when both sectionalizing switches on both sides of the fault boundary are successfully tripped and the three-phase voltage and three-phase current of the fault section drop to the preset isolation safety range.

8. The intelligent monitoring method for distribution network operation status based on wireless communication network according to claim 2, characterized in that, Step S4 specifically involves: After the electrical isolation of the faulty section is completed, the edge gateway parses the pre-planned power switching path in the emergency response plan package and obtains the identifiers of the target interconnection switch and its feeder. Perform a pre-closing verification on the target interconnecting switch, and send a closing command after the verification passes. After sending the closing command, if a closing confirmation signal is received within the preset response time, and the three-phase voltage and three-phase current of the restored power supply line are restored to the preset safe operating range, then the power supply restoration is determined to be successful; otherwise, the power supply restoration is determined to be unsuccessful and step S5 is executed.

9. The intelligent monitoring method for distribution network operation status based on wireless communication network according to claim 7, characterized in that, The pre-closing verification includes: Confirm that the sectionalizing switches on both sides of the fault boundary have been tripped; Calculate the available transfer capacity of the target power supply feeder and determine whether it is not less than the current total active load value of the non-faulty section downstream of the fault boundary; If all the above conditions are met, the verification is considered successful; otherwise, the verification is considered unsuccessful.

10. The intelligent monitoring method for distribution network operation status based on wireless communication network according to claim 8, characterized in that, Step S5 specifically involves: If any of the following situations are detected during the execution of steps S3 to S4: electrical isolation is not completed; power restoration fails; after power restoration, the effective value of the three-phase current of the line continues to exceed its overcurrent setting or the effective value of the three-phase voltage continues to be lower than the undervoltage setting; The edge gateway then checks whether the autonomous decision-making flag is enabled in the currently active contingency plan package; if not, it stops autonomous recovery and reports to the cloud platform. If so, based on the local network topology and real-time total active load value, traverse all tie switches and adjacent feeders that are electrically connected to the non-faulty section downstream of the fault boundary. Calculate the available transfer capacity of each adjacent feeder. If it is not less than the current total active load value of the non-faulty section downstream of the fault boundary, then the corresponding tie switch and adjacent feeder path are selected as candidate paths. The candidate paths are sorted in descending order of available transfer capacity, and the first one is selected as the alternative power restoration path. Send a closing command to the tie switch in the alternative power supply restoration path. If a closing confirmation signal is received within the preset response time, and the three-phase voltage and three-phase current in the non-faulty section are restored to the preset safe operating range, then the alternative power supply restoration is successful. If the alternative power supply restoration path generation fails or the alternative power supply restoration fails, and the preset termination conditions are met, then the autonomous restoration will stop and the cloud platform will be reported.

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