Low-voltage distribution line state monitoring method and system based on dual-mode communication

Abstract

The application provides a low-voltage distribution line state supervision method and system based on dual-mode communication, and belongs to the field of power line carrier communication. The current combined communication scheme is not perfect, and the terminal information collection and management of low-voltage transformer areas still have problems such as low receiving probability, more retransmission, and even island terminal conditions. The above method comprises the following steps: obtaining reference phase information on the transformer side, controlling multiple distribution terminals to upload local voltage phase segments within a preset supervision period; at the edge node, aligning the reference phase information with the local voltage phase segments uploaded by each distribution terminal, using least square estimation to obtain the phase difference of each distribution terminal relative to the reference phase information, and generating a phase correction table based on the phase difference; automatically correcting the phase label of each distribution terminal based on the phase correction table, and reorganizing the in-phase broadcast or multicast domain, and reassigning the communication time slots corresponding to the multicast domain.

Description

Technical Field

[0001] This application relates to the field of power line carrier communication technology, and in particular to a method and system for monitoring the status of low-voltage power distribution lines based on dual-mode communication. Background Technology

[0002] Under the dual-mode communication architecture of HPLC (High-speed Power Line Communication) and HRF (High-speed Radio Frequency), the system simultaneously possesses the local access advantages of power line communication and the flexible coverage capabilities of wireless communication. It can utilize the natural network infrastructure of power lines for rapid coverage while leveraging wireless links to enhance redundancy and anti-interference capabilities, thus better meeting the comprehensive requirements of reliability, continuity, and economy for the low-voltage distribution side of the smart grid. However, the current combined use of these two technologies is not perfect, and the collection and management of terminal information in low-voltage distribution areas still suffers from low reception probability, numerous retransmissions, and even isolated terminals. Summary of the Invention

[0003] This application provides a method and system for monitoring the status of low-voltage distribution lines based on dual-mode communication. This can solve the problems that the current combined use of the two methods is not perfect, and that the collection and management of terminal information in low-voltage distribution areas still suffers from low reception probability, many retransmissions, and even isolated terminals.

[0004] The first aspect of this application provides a method for monitoring the status of low-voltage power distribution lines based on dual-mode communication, including:

[0005] The reference phase information of the transformer side is obtained, and multiple distribution terminals are controlled to send local voltage phase segments within a preset monitoring period. The reference phase information is used to characterize the phase reference of the grid-side voltage, and the local voltage phase segment includes the zero crossover time information or equivalent phase vector information of the terminal-side voltage.

[0006] At the edge nodes, the reference phase information is aligned with the local voltage phase segments sent by each distribution terminal, and the phase difference of each distribution terminal relative to the reference phase information is obtained by least squares estimation. A phase correction table is then generated based on the phase difference.

[0007] The phase label of each distribution terminal is automatically corrected based on the phase correction table, and the in-phase broadcast or multicast domains are regrouped. At the same time, the communication time slots corresponding to the multicast domains are reallocated so that terminals whose multicast configuration fails due to the inconsistency between the phase label and the actual physical phase are pulled into the high-quality communication domain with consistent phase, thereby reducing the reporting interval jitter of the terminals and improving the multicast domain reuse efficiency.

[0008] The second aspect of this application provides a low-voltage power distribution line status monitoring system based on dual-mode communication, including:

[0009] The acquisition unit is used to acquire reference phase information on the transformer side and control multiple distribution terminals to send local voltage phase segments within a preset monitoring period. The reference phase information is used to characterize the phase reference of the grid-side voltage, and the local voltage phase segment includes zero crossover time information or equivalent phase vector information of the terminal-side voltage.

[0010] The calculation unit is used to align the reference phase information with the local voltage phase segments sent by each distribution terminal at the edge nodes, use least squares estimation to obtain the phase difference of each distribution terminal relative to the reference phase information, and generate a phase correction table based on the phase difference.

[0011] The correction unit is used to automatically correct the phase label of each distribution terminal based on the phase correction table, regroup the in-phase broadcast or multicast domains, and reallocate the communication time slots corresponding to the multicast domains, so that the terminals whose multicast configuration fails due to the inconsistency between the phase label and the actual physical phase are pulled into the high-quality communication domain with consistent phase, thereby reducing the reporting interval jitter of the terminals and improving the multicast domain multiplexing efficiency.

[0012] A third aspect of this application provides an electronic device, including a memory and a processor, wherein the processor is used to execute a computer program stored in the memory to implement the steps of the above-described low-voltage power distribution line status monitoring method based on dual-mode communication.

[0013] A fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-described method for monitoring the status of low-voltage power distribution lines based on dual-mode communication.

[0014] Considering that in low-voltage distribution transformer areas, in-phase broadcasting or multicast based on high-speed power line carrier communication typically relies on the premise of phase consistency, that is, terminals assigned to the same multicast domain are assumed to be in a physical environment with the same phase line or equivalent phase consistency. This allows for matching more stable coupling paths and lower transient interference in the selection of transmission time slots and reception windows. If there are phase line bridging issues, legacy issues from historical modifications, or errors in record-keeping in the transformer area, the phase label of the terminal may not match its actual physical phase. In such cases, the terminal may be incorrectly configured into a mismatched multicast domain and time slot resource. This manifests as a decrease in multicast reception success rate and an increase in retransmissions and backoffs. However, because communication may still be possible during certain periods without complete disconnection, this leads to a long-term phenomenon of inefficient but not completely disconnected isolated terminals. In summary, the low-voltage distribution line status monitoring method based on dual-mode communication provided in this application adopts a phase voiceprint recognition and automatic phase correction mechanism to automatically correct multicast domain configuration mismatch caused by phase ledger errors or phase line modification within the transformer area. Terminals are regrouped into multicast domains consistent with the actual physical phase and obtain matching communication time slot configurations, thereby reducing retransmission and backoff behaviors caused by multicast reception failures, significantly converging the time jitter distribution of terminal reporting intervals, reducing invalid occupation and duplicate transmissions within the multicast domain, and improving the effective utilization rate and service carrying capacity of multicast resources.

[0015] Correspondingly, the systems, electronic devices, and computer-readable storage media provided in the embodiments of the present invention also have the above-mentioned technical effects. Attached Figure Description

[0016] Figure 1 A flowchart illustrating a possible low-voltage power distribution line status monitoring method based on dual-mode communication, provided for an embodiment of this application;

[0017] Figure 2 A schematic structural block diagram of a possible low-voltage power distribution line status monitoring system based on dual-mode communication, provided for embodiments of this application;

[0018] Figure 3 A schematic diagram of the hardware structure of a possible low-voltage power distribution line status monitoring system based on dual-mode communication, provided for an embodiment of this application;

[0019] Figure 4 A schematic structural block diagram of a possible electronic device provided in an embodiment of this application;

[0020] Figure 5 This is a schematic structural block diagram of a possible computer-readable storage medium provided for embodiments of this application. Detailed Implementation

[0021] This application provides a method and related equipment for monitoring the status of low-voltage power distribution lines based on dual-mode communication. This method can solve the problems that the current combined use of the two methods is not perfect, and that the collection and management of terminal information in low-voltage distribution areas still suffers from low reception probability, many retransmissions, and even isolated terminals.

[0022] Please see Figure 1 The flowchart below illustrates a low-voltage power distribution line status monitoring method based on dual-mode communication, as provided in this application embodiment. Specifically, it may include:

[0023] S110-S130.

[0024] S110, acquire reference phase information on the transformer side, and control multiple distribution terminals to send local voltage phase segments within a preset monitoring period. The reference phase information is used to characterize the phase reference of the grid-side voltage, and the local voltage phase segment includes the zero-crossing time information or equivalent phase vector information of the terminal-side voltage.

[0025] S120, at the edge node, the reference phase information is aligned with the local voltage phase segment sent by each distribution terminal, the phase difference of each distribution terminal relative to the reference phase information is obtained by least squares estimation, and a phase correction table is generated based on the phase difference.

[0026] S130, based on the phase correction table, the phase label of each distribution terminal is automatically corrected, and the in-phase broadcast or multicast domain is regrouped. At the same time, the communication time slots corresponding to the multicast domain are reallocated so that the terminals whose multicast configuration fails due to the inconsistency between the phase label and the actual physical phase are pulled into the high-quality communication domain with consistent phase, so as to reduce the reporting interval jitter of the terminals and improve the multicast domain reuse efficiency.

[0027] It is understandable that in low-voltage distribution substations, in-phase broadcasting or multicast in carrier communication typically assumes that terminals on the same phase line have similar voltage phase references. This allows for reduced collision probability and improved multicast multiplexing efficiency during media access, multicast domain partitioning, and time slot allocation. However, when there are phase line bridging issues, legacy historical modifications, or incorrect record labeling, the labeled phase of a terminal may not match its actual physical phase. This leads to the following: the terminal is incorrectly assigned to a multicast domain with a different phase than its actual phase. Consequently, within multicast time slots or in-phase transmission windows, the terminal is placed on an unfavorable coupling path and experiences higher noise levels, resulting in reduced reception probability and increased retransmissions. Furthermore, because the carrier link is not completely disconnected, the terminal exhibits prolonged inefficiency but not complete disconnection, such as alternating reporting intervals and recovery periods, forming isolated terminals that are difficult to detect through conventional disconnection alarms. The aforementioned phase acoustic signature, in this scheme, is essentially the stable phase relationship between the network-side phase reference and the terminal-side voltage phase within the same substation area. The transformer-side reference phase information provides a phase benchmark for the grid-side voltage, such as a zero-crossing time sequence based on the transformer secondary voltage. The local voltage phase segment on the terminal side provides observations of the voltage phase at the terminal connection point, also represented by a zero-crossing time sequence or an equivalent phase vector. Under stable power frequency conditions, the phase at the terminal connection point has an estimable fixed offset relative to the transformer-side phase, such as a small fluctuation. This offset corresponds to a combination of factors including the phase line where the terminal is located, the connection position, and the line impedance distribution. Therefore, when the terminal's labeled phase is inconsistent with the actual physical phase, the terminal's phase acoustic signature will exhibit a characteristic inconsistent with its labeled phase, allowing edge nodes to automatically correct the phase label. Furthermore, zero-crossing detection is affected by noise, harmonic distortion, and voltage waveform clipping, resulting in random errors and occasional outliers in the single-cycle estimated phase difference. Least squares estimation aligns and integrates the phase difference across multiple periods to minimize the overall error energy, thus providing the ability to suppress random jitter by averaging and enhancing robustness to a small number of outlier sampling points. It can be combined with outlier removal strategies and can also output the confidence level of the phase difference estimate to determine whether to correct immediately or enter the verification mode.

[0028] For example, edge nodes or distribution area gateways are deployed on the transformer substation side, and voltage sampling and isolation circuits are set on the secondary busbar or low-voltage outgoing line side of the transformer to obtain reference phase information that can characterize the grid-side power frequency phase. In one possible implementation, the reference phase information is implemented using a reference zero-crossing time sequence. The edge node detects the positive or negative zero-crossing points of the grid-side voltage waveform through a zero-crossing detection circuit, records the zero-crossing times within several consecutive power frequency cycles in the form of a timestamp sequence, and simultaneously saves the sampling window number, power frequency cycle estimate, and waveform quality identifier for subsequent alignment and abnormal sample removal. In another possible implementation, the reference phase information is implemented using a reference phase vector. The edge node extracts the power frequency fundamental component of the sampled voltage waveform and calculates its phase angle to form a phase vector sequence arranged periodically, and similarly saves the sampling window number and waveform quality identifier. To reduce the jitter caused by harmonics, waveform clipping, or sudden noise to zero-crossing detection, band-pass or low-pass filtering can be performed on the voltage sampling signal before zero-crossing detection or phase estimation to highlight the power frequency fundamental characteristics, thereby providing a stable and consistent phase reference for all terminals in the distribution area.

[0029] For example, within a preset monitoring period, edge nodes control multiple distribution terminals to periodically collect and upload local voltage phase segments by issuing parameters or adopting preset strategies. These phase segments include zero-crossing time information or equivalent phase vector information of the terminal-side voltage. In the method using zero-crossing time information, the distribution terminal uses a local voltage sampling and zero-crossing detection module to record the zero-crossing times of several consecutive power frequency cycles within a short sampling window. The zero-crossing time sequence is then compressed and encoded differentially before being uploaded to reduce uplink bandwidth usage. Simultaneously, the uploaded message carries the terminal identifier, sampling window number, estimated power frequency cycle value of the terminal side, and sampling quality identifier. In the method using equivalent phase vectors… In this method, the terminal estimates the fundamental phase of the voltage waveform within the sampling window and sends up a phase vector sequence, which also carries the sampling window number and quality identifier. To balance the continuity of regulatory data and communication resource overhead, the sampling window length can be set to cover several power frequency cycles, and the uploading cycle can be set to minutes or hours. The uploading frequency can be temporarily increased when the terminal communication quality deteriorates or islanding symptoms appear. The terminal can prioritize the use of high-speed power line carrier communication links for uploading. When the carrier link is interfered with, causing uploading failure or an increase in the number of retransmissions, the high-speed wireless radio frequency communication link can be switched or used to carry uploading phase segments to ensure that edge nodes continuously obtain key observation data for phase correction.

[0030] For example, after receiving reference phase information and local voltage phase segments from multiple terminals, the edge node aligns them within the same sampling window and uses least squares estimation to obtain the phase difference between the terminal and the reference phase. In a specific implementation, the edge node first performs window matching between the terminal-uploaded segments and the reference phase information according to the sampling window number. When there is window number drift or a deviation between the terminal clock and the edge clock, the edge node can further perform secondary alignment based on the power frequency cycle characteristics. For example, it can search for the alignment offset that minimizes the sum of squared residuals between the reference zero-crossing sequence and the terminal zero-crossing sequence, so that the alignment process does not depend on absolute clock consistency. Subsequently, least squares fitting is performed on the aligned sequence, with zero... In the implementation using the crossover time sequence as an example, the edge node constructs a time offset model between the terminal zero-crossing time and the reference zero-crossing time, and solves for the time offset estimate that minimizes the sum of squared residuals. Then, it converts the time offset into a phase difference based on the power frequency period. To prevent voltage waveform distortion or sudden noise from causing individual zero-crossing point anomalies, the edge node can perform outlier removal processing before fitting. For example, it can remove a few zero-crossing points whose residuals exceed a preset threshold before fitting, thereby improving the stability of the phase difference estimation. At the same time, the edge node outputs the confidence index of the phase difference estimation, such as generated by the root mean square of the fitting residuals, the proportion of effective samples, or the proportion of outliers, which is used to determine whether the phase correction action takes effect immediately or enters the review process.

[0031] For example, the edge node generates a phase correction table based on the phase difference estimation result, and automatically corrects the phase labeling of the distribution terminal accordingly. The phase correction table includes at least the terminal identifier, the original phase label, the estimated phase difference value, the confidence level, the corrected phase category or correction amount, the generation time, and the applicable window range. The corrected phase category can be obtained by mapping the phase difference to a preset phase interval to correct phase labeling errors. When performing automatic correction, the edge node can set trigger rules, such as when the confidence level reaches a preset threshold and the phase category corresponding to the phase difference matches the original phase labeling. When inconsistencies occur, the phase label of the terminal is updated to the corrected phase category, and the update action is recorded as a phase correction event. When the confidence level is insufficient or the phase difference is near the phase boundary, the edge node may temporarily not change the phase label, but only mark the terminal as pending review. The phase category will be repeatedly estimated in several subsequent monitoring cycles to confirm its stability before the correction is performed, thereby reducing the probability of incorrect correction under waveform distortion or short-term disturbances. The phase correction table can be stored locally on the edge node and synchronized to the area management system for subsequent multicast domain regrouping, time slot reallocation, and operation and maintenance traceability.

[0032] For example, after completing the automatic phase label correction, the edge node regroups the in-phase broadcast or multicast domains according to the corrected phase labels and reallocates the communication time slots corresponding to the multicast domains. This guides terminals whose multicast configurations fail due to inconsistencies between the phase labels and the actual physical phases into high-quality communication domains with consistent phases. In specific implementations, the edge node groups terminals with the same corrected phase category into the same multicast domain, updates the multicast domain's member list, multicast parameters, and delivery strategy, and recalculates the time slot resource allocation scheme for each multicast domain. This ensures that the multicast transmission window matches the actual physical phase characteristics of the terminals, thereby reducing conflicts and... Retransmission probability; Under the dual-mode communication architecture, edge nodes can use high-speed power line carrier communication as the main carrier medium for local terminal access and multicast distribution, while allocating high-speed radio frequency communication as a redundant link or anti-interference supplementary link for critical regulatory messages or terminals in the handover transition period, so as to avoid the discontinuity of regulatory data during regrouping and time slot adjustment; After the regrouping is completed, the edge nodes can continuously count the reporting success rate, retransmission count and reporting interval sequence of the terminal within a preset observation window, and judge whether the towing is successful based on the statistical results. If necessary, it can trigger re-estimation and reallocation to ensure that the terminal remains stably in the high-quality communication domain with phase consistency.

[0033] In summary, the phase acoustic pattern proposed in this scheme is not an audio acoustic pattern, but rather uses the stable phase relationship between the grid-side reference phase and the terminal-side voltage phase as an identifiable feature. A unified phase reference is provided through a transformer-side reference zero-crossing time sequence or reference phase vector. Phase observations at the terminal access point are provided through zero-crossing time segments or equivalent phase vectors transmitted from the terminal side. After aligning over multiple power frequency cycles, the phase difference is estimated, thus presenting the terminal's true physical phase in a calculable manner. Considering that voltage waveform distortion, noise disturbances, and sampling jitter in the field can cause instability in single-cycle zero-crossing detection, this scheme uses least squares estimation to fit the phase difference over multiple cycles, thereby statistically suppressing random errors and improving the stability of phase difference estimation. When the estimation result shows that the phase corresponding to the terminal phase difference is inconsistent with its ledger label, the edge node outputs a phase correction table and triggers multicast domain regrouping and time slot reallocation, allowing the misgrouped terminal to return to a high-quality communication domain consistent with the true physical phase, thereby reducing reporting interval jitter and improving multicast domain multiplexing efficiency.

[0034] In some examples, it also includes:

[0035] After the regrouping and redistribution are completed, the high-speed power line carrier communication is used to carry the local access links of at least some terminals, and the high-speed wireless radio frequency communication is used to provide redundant transmission links or anti-interference supplementary links for at least some terminals, so as to monitor the status of the continuity and reliability of terminal reporting of low-voltage power distribution lines.

[0036] Understandably, in the communication environment of low-voltage distribution substations, high-speed power line carrier communication relies on the existing power lines to form a natural network, which has the advantages of wide local access coverage and low construction and renovation costs. However, its link quality is easily affected by factors such as switching power supplies, frequency converters, nonlinear loads, changes in grounding status, and changes in branch topology, resulting in phenomena such as time-varying noise enhancement, transient impedance mutations, and frequency band selective fading. High-speed wireless radio frequency communication has the ability to transmit over-the-air interface independently of the physical coupling path of power lines, and can provide alternative transmission paths across media when the carrier link is interfered with or locally coupled deteriorated. However, its coverage is affected by factors such as obstruction, channel congestion, and transmission power limitations. Based on the aforementioned complementary characteristics, after completing the multicast domain regrouping and time slot reallocation, this scheme uses high-speed power line carrier communication as the primary local access link for most terminals to maintain economy and coverage. At the same time, it configures high-speed wireless radio frequency communication as a redundant transmission link or an anti-interference supplementary link for at least some terminals, so that the regulatory data of the same terminal has a switchable or parallel transmission path on different media. The edge nodes thereby implement state monitoring of the continuity and reliability of the terminal reporting link. That is, by continuously statistically analyzing and judging indicators such as reporting success rate, packet loss rate, retransmission count, acknowledgment delay and reporting interval stability, wireless supplementation or redundant reporting is triggered when the carrier link experiences short-term degradation or sudden interference. This mechanism reduces the impact of single medium failure on the continuity of regulatory data and improves reliability and traceability through cross-media consistency verification and event logging.

[0037] For example, after regrouping and redistribution, the edge node establishes a dual-mode link capability profile for each distribution terminal within the transformer area. This capability profile includes at least whether the terminal possesses high-speed power line carrier communication capability, whether it possesses high-speed radio frequency communication capability, a list of available channels for both media, historical reporting success rate, average acknowledgment delay, retransmission count statistics, and an indicator of the impact of the terminal's installation location on wireless coverage. Based on this capability profile, the edge node determines the primary and supplementary bearer media strategies for each terminal. For most terminals, high-speed power line carrier communication is set as the primary bearer media to form a local access link, and for those meeting preset requirements… The terminal is configured with high-speed wireless radio frequency communication as a redundant transmission link or an anti-interference supplementary link. The preset conditions may include the terminal being a key monitored object, the terminal having historical islanding symptoms, the terminal carrier link still having high retransmission before and after multicast domain adjustment, the terminal being located in a branch near a noise source, or the terminal's wireless coverage quality reaching the usable threshold. When the configuration is implemented, the edge node sends medium selection parameters to the terminal, including the preferred medium identifier, allowed medium switching conditions, supplementary reporting trigger threshold, and transmission priority rules when both media are available at the same time, so that the terminal or edge node can perform subsequent redundancy supplementation behavior according to a unified strategy.

[0038] For example, in daily operation, edge nodes carry local access links for at least some terminals using high-speed power line carrier communication. Specifically, this includes terminals sending status reporting messages uplink on the carrier link according to a preset monitoring cycle, and sending downlink commands to terminals via the carrier link when parameters or configuration updates are required. Edge nodes establish basic statistics for continuous monitoring of each terminal. These statistics include at least the terminal's reported arrival timestamp sequence, adjacent reporting interval sequence, number of missing reports, carrier link acknowledgment delay statistics, retransmission count statistics, and link quality indicators available at the carrier physical layer. The above statistics are updated on a rolling basis according to time windows to form a baseline for continuity and reliability. To avoid misjudging service-side congestion as link failure, edge nodes can simultaneously record the multicast domain and time slot resource allocation status as well as the overall carrier occupancy rate of the distribution area, so as to distinguish between delays caused by resource contention and failures caused by physical link degradation in subsequent judgments.

[0039] For example, when an edge node detects that at least one terminal meets the supplementary triggering condition in the rolling statistics, it enables high-speed wireless radio frequency communication to provide a redundant transmission link or an anti-interference supplementary link for the terminal. The supplementary triggering condition may include the number of missing reports exceeding a threshold within a preset time window, the acknowledgment delay continuously exceeding a threshold, the number of retransmissions significantly increasing, the reporting interval abnormally lengthening, or the jitter significantly increasing. In one implementation, the edge node issues a supplementary reporting instruction to the target terminal, causing the target terminal to prioritize sending the same regulatory message via high-speed wireless radio frequency communication in the next report, or to send a supplementary report after carrier reporting. When confirmation is received within a preset confirmation time limit, a backup copy is sent via a wireless link. In another implementation, the terminal automatically triggers a supplementary wireless report based on locally detected carrier retransmission anomalies or confirmation timeouts, and carries the trigger reason identifier and local statistical information in the supplementary message to facilitate edge nodes in determining the type of interference. For redundant transmission, the edge node or terminal generates a unique message identifier for the same regulatory message and carries it in the dual-media message, enabling the edge node to perform deduplication and consistency verification at the receiving end, avoiding redundant copies being repeatedly included in the service data, while ensuring the reliability goal of at least one link successfully arriving.

[0040] For example, after receiving reports from high-speed power line carrier communication and high-speed radio frequency communication, the edge node performs deduplication processing on multiple media copies of the same regulatory message based on the message's unique identifier, and performs consistency verification on key fields between the copies. These key fields include at least the terminal identifier, acquisition time, core status variable value, and integrity check code. When the consistency verification passes, the edge node counts the regulatory message as a valid report and updates the continuity and reliability indicators of the corresponding terminal. The continuity indicator can be characterized by the reporting missing rate and reporting interval stability, while the reliability indicator can be characterized by the successful confirmation rate, retransmission count, and first-pass rate. Quality statistical characterization; when the consistency check fails, the edge node records the event as an abnormal reporting event, and attributes the cause of the abnormality based on the received channel quality indicator, acknowledgment delay and error check results of each medium. For example, it may be marked as bit error caused by carrier link distortion, delay exceeding the limit caused by wireless link congestion or data inconsistency caused by terminal acquisition abnormality. Based on this, the edge node forms a status monitoring conclusion, including whether the terminal is currently in a carrier-only available state, a carrier-degraded state with wireless supplementation in effect, or a high-risk state where both links are unstable. The monitoring conclusion is then output to the area operation and maintenance system for subsequent maintenance scheduling.

[0041] For example, to ensure that dual-mode redundancy supplementation is not just a one-time remedy, edge nodes solidify cross-media supplementation behavior and its effects into traceable policy updates and audit records. These audit records must include at least the terminal identifier, trigger time, trigger condition type, carrier link statistics within the trigger window, wireless link reception statistics, supplementation method type, and the improvement in continuity indicators after supplementation. When an edge node detects that a terminal repeatedly triggers wireless supplementation within multiple windows and the supplementation effect is significant, it can upgrade the terminal to a long-term dual-mode protection target and adjust its primary bearer and supplementation strategy, such as increasing the trigger priority of wireless backup or extending the duration of wireless supplementation. If supplementation still fails to improve the situation, the edge node marks the terminal as requiring on-site investigation and provides possible cause categories in the maintenance recommendations, such as the addition of branch noise sources, loose wiring leading to coupling degradation, or wireless obstruction causing insufficient coverage. Through the above policy solidification and audit records, the system can maintain a stable level of terminal reporting continuity and reliability in transformer substation environments with long-term topology and load changes, and provide interpretable and quantifiable evidence for operation and maintenance.

[0042] In some examples, the reference phase information includes a zero-crossing time sequence of the transformer-side voltage, the local voltage phase segment includes a zero-crossing time sequence of the terminal-side voltage, and the generation of a phase correction table based on the phase difference includes:

[0043] The edge node performs time alignment on the zero-crossing time sequence to establish a time offset model between the terminal-side zero-crossing time and the network-side zero-crossing time, and converts the time offset model into a phase difference to generate the phase correction table.

[0044] In some examples, the phase correction table contains a correspondence between terminal identifiers and phase correction values, whereby the phase correction values ​​are used to map the original phase label of the terminal to a corrected phase label. The regrouping of in-phase broadcast or multicast domains includes:

[0045] Based on the corrected phase label, the terminal is assigned to a phase-consistent multicast domain, and the broadcast or multicast parameters of the multicast domain are updated to ensure that the terminal's in-phase broadcast or multicast reception conditions are consistent with its actual physical phase.

[0046] In some examples, the condition monitoring of the continuity and reliability of terminal reporting for low-voltage distribution lines includes:

[0047] The statistical terminal reports the interval sequence within a preset monitoring window, and calculates the variance of the reporting interval jitter as a link quality indicator.

[0048] After completing the automatic phase correction and the multicast domain regrouping and time slot reallocation, the link quality indicators before and after the update are compared. When the link quality indicators meet the preset improvement threshold, a regulatory conclusion that the phase mismatch correction is successful is output, and the corresponding terminal is marked as having recovered from the isolated terminal state.

[0049] Understandably, in the implementation of phase characterization using zero-crossing time sequences, the power frequency voltage waveform exhibits strong periodicity during stable operation. The zero-crossing times of the voltage on the transformer side and the terminal side show an approximately equiperiodic repetition relationship on the same time scale. Since the actual physical phase of the terminal access point may differ from the ledger label, the zero-crossing time on the terminal side will exhibit a statistically stable time offset relative to the zero-crossing time on the network side. This time offset has a definite conversion relationship with the power frequency period, so the time offset can be converted into a phase difference, thereby automatically correcting the terminal phase label. On the other hand, isolated terminals are not completely offline. Their typical manifestation is that the reporting interval exhibits significant jitter and a long tail over a period of time. The root cause is often the mismatch between the multicast domain and time slot configuration, leading to reception failure, retransmission, and backoff causing reporting delays. Therefore, using the jitter variance of the reporting interval sequence as a link quality indicator can quantify the stability of the terminal link without additional hardware. After completing automatic phase correction, regrouping the multicast domain, and reallocating time slots, the terminal is in a more matched phase-consistent communication domain, resulting in improved communication success rate, reduced retransmissions and backoffs, and a significant decrease in reporting interval jitter variance. By comparing the indicators before and after the update with the preset improvement threshold, a regulatory conclusion that the phase mismatch correction has been successful can be output, and the terminal recovery status can be marked, thereby achieving quantifiable and auditable status supervision.

[0050] For example, edge nodes acquire grid-side reference phase information on the secondary side of the transformer or the low-voltage outgoing line side through voltage sampling and zero-crossing detection modules. This reference phase information is represented as a reference zero-crossing time sequence, specifically recording the zero-crossing times of several consecutive power frequency cycles within a preset sampling window. The sequence is then appended with a sampling window identifier, sampling start and end times, sequence length, power frequency cycle estimate, and waveform quality identifier. Multiple distribution terminals acquire local voltage within the same or matching sampling windows and form a terminal-side zero-crossing time sequence through a local zero-crossing detection module. The terminal then records the terminal-side zero-crossing times... The sequence number, along with the terminal identifier, sampling window identifier, estimated power frequency period on the terminal side, zero-crossing detection quality identifier, and verification information for verifying sequence integrity, is sent to the edge node. To reduce the timing jitter caused by harmonic distortion, waveform clipping, or noise spikes to zero-crossing detection, both the network side and the terminal side can perform fundamental frequency emphasis filtering on the sampled voltage before zero-crossing detection, or perform anomaly screening based on the consistency of adjacent periods on the zero-crossing time sequence, and use the screening results as quality identifiers for sample selection in subsequent model fitting, thereby ensuring that subsequent time alignment and time offset models are built on a usable data quality basis.

[0051] For example, after receiving the reference zero-crossing time sequence and the terminal-side zero-crossing time sequence, the edge node first performs window-level matching based on the sampling window identifier to ensure that the two sequences are comparable within the same or adjacent monitoring windows. When there is terminal upload delay, window identifier drift, or inaccurate window boundaries due to inconsistency between the edge node and the terminal's local clock, the edge node further performs sequence-level time alignment on the two sequences: using the reference zero-crossing time sequence as a reference, the edge node searches for the alignment offset that minimizes the period difference residual between the two sequences within a limited offset search range, and performs alignment simultaneously with the terminal's local clock. When considering the small fluctuations in the power frequency cycle, this can be manifested as calculating the time difference between the terminal sequence and the reference sequence at the corresponding sequence number after alignment and checking whether it exhibits a stable distribution as the sequence number changes. If the residual shows significant drift after alignment, the window is marked as potentially having frequency estimation bias or sequence missing, triggering the reselection of a valid subsequence or shortening of the alignment window to improve alignment reliability. Through the above window-level matching and sequence-level alignment, the edge nodes establish a one-to-one correspondence that can be used to fit the time offset model without relying on the absolute clock consistency between the terminal and the gateway, laying the foundation for subsequent phase difference estimation.

[0052] For example, after time alignment is completed, the edge node constructs a time offset model of the terminal-side zero-crossing time relative to the network-side zero-crossing time. Specifically, it uses the difference between each pair of aligned zero-crossing times as an observation sample and fits these differences within a preset sampling window to obtain a representative time offset parameter characterizing the terminal relative to the network side. To suppress the influence of random jitter in zero-crossing detection and a small number of outliers on the estimation results, the edge node can perform weighted fitting or least-squares fitting on the difference samples, assigning lower weights to samples with poor waveform quality, or first removing outliers whose differences significantly deviate from the main distribution before fitting, to obtain a stable time offset estimate. After obtaining the time offset estimate, the edge node adjusts the time based on the power frequency cycle estimate within the window. The offset is converted into a phase difference. The conversion process uses a consistent conversion benchmark and retains the period parameters required for the conversion to ensure that the phase difference is comparable across different windows. Subsequently, the edge node generates a phase correction table, which includes at least the terminal identifier, the estimated time offset, the converted phase difference, the estimated confidence level, the applicable window range, the original phase label, and the corrected phase label mapped from the phase difference. The estimated confidence level can be generated from the fitted residual statistics, the proportion of effective samples, or the proportion of outliers, and is used to decide whether to immediately perform phase label updates or enter the review process. After the phase correction table is generated, it can be stored locally on the edge node and synchronized to the regional operation and maintenance system, serving as the basis for multicast domain regrouping and time slot reallocation, as well as the basis for subsequent audit traceability.

[0053] For example, the edge node records the arrival timestamp of each terminal's report within a preset monitoring window, and constructs a reporting interval sequence based on the arrival timestamps of two adjacent valid reports, thereby transforming the stability of terminal reporting into a calculable time-series indicator. When constructing the reporting interval sequence, the edge node performs deduplication processing on duplicate arrivals of the same monitoring message, and only uses the first valid arrival for interval calculation when there are multiple arrivals due to retransmissions, to avoid miscounting duplicate arrivals of the same message as multiple reporting events. Subsequently, the edge node calculates the jitter variance of the reporting interval sequence as a link quality indicator, where a larger jitter variance usually indicates that the terminal link is more unstable and there is more frequent delay propagation caused by acknowledgment timeouts, retransmissions, and backoffs. To enhance the interpretability of the indicator, the edge node can simultaneously record the retransmission count statistics, acknowledgment delay statistics, and reporting missing count statistics within the window, and use them together with the jitter variance as auxiliary interpretive items for the link quality indicator, so that in subsequent comparison and judgment, it can distinguish between normal interval changes caused by service scheduling and abnormal jitter caused by link mismatch.

[0054] For example, after completing automatic phase correction and multicast domain regrouping and time slot reallocation, the edge node recalculates the terminal's reporting interval jitter variance within a preset monitoring window of the same caliber, and compares it with the jitter variance in the window before the update to obtain the improvement margin. The edge node sets a preset improvement threshold, which can be defined as the percentage decrease in jitter variance reaching a certain threshold, or as the absolute value decrease in jitter variance reaching a certain threshold. It can further combine a decrease in retransmission count or a reduction in acknowledgment delay as auxiliary judgment conditions to avoid misjudgments caused by relying on a single indicator. When the comparison result meets the preset improvement threshold, the edge node outputs a monitoring conclusion that the phase mismatch correction is successful. The corresponding terminal is marked as having recovered from the isolated terminal state, and the regulatory conclusion is written into the audit log. The audit log includes at least the terminal identifier, the time of correction, the range of the regulatory window used, the jitter variance before and after the update, the improvement magnitude, the phase correction table version number, and the multicast domain and timeslot configuration version number. When the comparison result does not meet the preset improvement threshold, the edge node marks the terminal as needing further investigation or verification, and can trigger actions such as increasing the phase segment uploading frequency, expanding the alignment window, or re-estimating the phase difference, so as to continue to verify in subsequent windows whether there are residual phase mismatch, new branch noise sources, or poor wiring contact, thereby making the status supervision have sustainable iterative engineering feasibility.

[0055] Understandably, by performing time alignment on the zero-crossing time sequence and establishing a time offset model, edge nodes can obtain a stable time offset estimate of the terminal relative to the network side without relying on additional phase measurement instruments. This estimate is then converted into a phase difference and written into the phase correction table. This transforms the problem of potentially incorrect phase in the ledger, which is difficult to detect directly, into a calculable, recordable, and verifiable data result. This effect can be verified by the stability of the phase difference estimate within multiple consecutive monitoring windows. For example, if the estimated time offset and phase difference of the same terminal remain consistent with each other and have a high confidence level in multiple windows, it indicates that the phase acoustic signature is reliable. At the same time, the association record between the phase correction table and the multicast domain grouping configuration version provides an audit basis for explaining why the terminal was regrouped, enhancing the traceability of the project. As a link quality indicator, the jitter variance of the reporting interval can directly capture the typical abnormal patterns of isolated terminals, namely, the unstable diffusion of the reporting interval under the influence of retransmission and backoff. After automatic phase correction and completion of multicast domain and timeslot configuration updates, the terminal enters a more matched phase-consistent communication domain, improving multicast reception success rate and reducing retransmission and backoff. Therefore, the dispersion of the reporting interval sequence should converge, manifested as a significant decrease in jitter variance. For the operation and maintenance side, outputting the successful correction conclusion and marking the recovery transforms isolated terminals from difficult-to-detect chronic problems into automatically identifiable and verifiable status events, improving the efficiency and objectivity of station communication maintenance.

[0056] In some examples, it also includes:

[0057] A compliance self-test process for passive sideband detection is performed at the gateway, the compliance self-test process including: recording the adjacent channel noise baseline used to characterize the noise level during adjacent channel idle periods;

[0058] When a change in equipment temperature rise or a sudden change in load is detected, the sampling frequency during the adjacent channel idle period is increased or the sampling duration is extended to obtain the adjacent channel noise monitoring sequence.

[0059] The adjacent channel noise monitoring sequence is compared with the adjacent channel noise baseline to determine whether there is an abnormality in the sideband leakage based on the change amplitude or rate of change of the noise floor.

[0060] In some examples, it also includes:

[0061] When the result of the difference analysis meets the triggering condition for the sideband leakage anomaly, the gateway generates a sideband leakage anomaly event and issues a compliance handling instruction, which is used to trigger the target device to perform a transmit power backoff operation.

[0062] The sideband leakage anomaly event will be written into the audit log. The audit log will include at least the time of the anomaly, the duration of the anomaly, the execution result of the transmit power rollback operation, and the corresponding device identifier, for subsequent compliance tracing and risk auditing.

[0063] It is understandable that in the actual operation of high-speed power line carrier communication or high-speed wireless radio frequency communication equipment, the transmission link may experience enhanced sideband leakage when the temperature rises, device parameters drift, or load changes. This manifests as an increase in the noise floor, spectral expansion, or widening of the noise skirt at adjacent frequencies in the transmission band. Traditional compliance inspections often rely on spot checks with external instruments, which is insufficient to cover intermittent over-limits caused by temperature rise and load fluctuations. This solution utilizes the observability of adjacent channel idle periods to indirectly observe sideband leakage by measuring adjacent channel noise at the gateway: when the adjacent channel is idle at the scheduling level, its noise level is normally determined by ambient noise and the background of the receiving link, and its statistical characteristics are relatively stable in the short term. Once the equipment experiences abnormal sideband energy leakage due to changes in operating conditions, even if no effective payload is transmitted directly in the adjacent channel, it will be reflected in the adjacent channel noise measurement results at the gateway in the form of an increase in the noise floor or an abnormal rate of change. By recording the adjacent channel noise baseline and encrypting the sampling during temperature rise changes or load abrupt changes to form a noise monitoring sequence, and then performing difference analysis between the monitoring sequence and the baseline, sideband leakage anomalies can be determined; when the anomaly meets the triggering conditions, the transmit power is immediately triggered and an audit record is formed, so that compliance risks can be detected and quickly blocked in a timely manner without the need for external inspections, while providing verifiable data evidence for subsequent compliance traceability.

[0064] For example, during system initialization, periodic maintenance windows, or periods when the network is in a stable operating state, the gateway selects at least one adjacent frequency band adjacent to the service operating frequency band and confirms that the adjacent frequency is in an idle period under the current scheduling configuration, so that there is no effective service transmission or negligible service occupation in the sampling window. The gateway calls the energy measurement capability of the RF receiving or carrier receiving link to sample the adjacent frequency noise power multiple times within the preset sampling window. The sampling results include at least the noise power value of each sample, the sampling timestamp, the sampling duration, the receiving gain level, and the current temperature reading. The sampling results are statistically summarized to form the adjacent frequency noise baseline. The adjacent frequency noise baseline may include the mean, standard deviation, and quantile threshold used to characterize the upper bound of the noise distribution. To avoid the accidental writing of external electromagnetic interference into the baseline, the gateway can simultaneously check the short-term stability and the proportion of sudden spikes in the adjacent frequency noise when establishing the baseline. If obvious abnormalities are found, the baseline establishment is delayed or abnormal sampling segments are removed, thereby ensuring that the adjacent frequency noise baseline can represent the background level of adjacent frequency noise when the equipment is operating normally and compliantly, and serve as a unified comparison benchmark for subsequent difference analysis.

[0065] For example, the gateway continuously acquires operational status information related to the transmission link and detects events such as changes in device temperature rise or sudden load changes. Temperature rise changes can be determined by the change in temperature sensor readings of key components exceeding a threshold within a unit of time. Load changes can be determined by changes in transmission power settings, transmission duty cycle, transmission modulation parameters, or power supply current reaching a threshold. When any of these events is detected, the gateway enters a compliance self-check encrypted observation mode. While the adjacent channel remains idle, the gateway increases the sampling frequency of adjacent channel noise or extends the duration of a single sampling to form an adjacent channel noise monitoring sequence. This monitoring sequence includes at least multiple consecutively sampled noise power values ​​and their timestamps, and is associated with the temperature readings, load status parameters, receiver gain levels, and scheduling idle indicators for that period. To ensure the comparability of the monitoring sequences, the gateway maintains consistency between the adjacent channel selection and the receiver link measurement aperture during encrypted observation. For example, it maintains the same measurement bandwidth, the same gain strategy, or normalizes gain changes, enabling subsequent difference analysis to more accurately attribute noise changes to sideband leakage risk rather than measurement aperture drift.

[0066] For example, after obtaining the adjacent channel noise monitoring sequence, the gateway performs a difference analysis between the monitoring sequence and the adjacent channel noise baseline to determine whether there is an anomaly in sideband leakage based on the magnitude or rate of change of the noise floor. In one implementation, the gateway calculates the statistics of the noise power in the monitoring sequence and compares them with the baseline statistics. For example, it compares the mean, quantiles, or proportion of consecutive samples exceeding the threshold of the monitoring sequence with the mean and baseline quantile thresholds of the baseline. If the monitoring sequence shows a noise increase exceeding the upper limit threshold of the baseline within a preset duration, an anomaly is determined to exist. In another implementation, the gateway focuses on analyzing the rate of change of noise and calculates the difference between adjacent sampling points in the monitoring sequence. The changes over a unit of time are evaluated, and an anomaly is determined when the changes exceed the normal fluctuation range of the baseline phase and are temporally correlated with temperature rise or load mutation events. To reduce misjudgments caused by external interference, the gateway can perform consistency verification by combining adjacent channel idle flags. That is, noise boosting is only used for sideband leakage determination when it is confirmed that there is no service occupation of the adjacent channel within the sampling window. At the same time, cross-validation can be performed on multiple adjacent frequency points. If multiple adjacent frequency points show synchronous boosting, the anomaly confidence level is increased. The difference analysis output includes at least the anomaly determination result, anomaly confidence level, anomaly type flag such as amplitude boosting or rate mutation, and corresponding evidence fragment index for subsequent processing and auditing.

[0067] For example, when the difference analysis results meet the sideband leakage anomaly triggering conditions, the gateway generates a sideband leakage anomaly event and issues a compliance handling instruction to trigger the target device to perform a transmit power backoff operation. The sideband leakage anomaly triggering conditions can be composed of rules such as anomaly confidence reaching a threshold, noise rise exceeding a threshold and lasting for more than a minimum duration, or noise change rate exceeding a threshold and being closely related to temperature rise or load abrupt changes. When generating the anomaly event, the gateway assigns a unique event identifier to the event and records the associated adjacent frequency points, sampling window range, anomaly judgment evidence index, and trigger rule hit items. The compliance handling instruction at least includes the target device identifier and power... The rollback range or rollback level, rollback activation time, and rollback duration strategy are specified. After receiving the compliance handling instruction, the target device adjusts its transmit power setting to reduce the risk of sideband leakage and returns a handling execution result receipt to the gateway. The receipt includes at least whether the rollback was successful, the current transmit power status after the rollback, the execution delay, and possible reasons for failure. To avoid unnecessary impact on critical services, the gateway can be configured with a tiered handling strategy. For example, it can prioritize a small rollback and observe whether the adjacent channel noise decreases. If the noise still does not recover, it can then perform a further rollback or enter a more stringent restriction mode, thereby achieving a configurable engineering balance between compliance risk control and business continuity.

[0068] For example, the gateway writes the sideband leakage anomaly and its handling process into the audit log for subsequent compliance tracing and risk auditing. The audit log includes at least the time of the anomaly, the duration of the anomaly, the execution result of the transmit power backoff operation, and the corresponding device identifier. In a more specific implementation, the audit log may also include the adjacent channel noise baseline version number, the adjacent channel noise monitoring sequence summary statistics during the triggering period, the anomaly judgment type and confidence level, the details of the triggering condition hit, the summary of the handling instruction content, the target device receipt information, and the retest results after handling. This allows maintenance personnel to review the basis for the anomaly and the handling process without the need for external testing instruments. The gateway can set an anti-tampering storage strategy for the audit log, such as writing key fields into an event log that only adds and does not modify, and generating integrity verification information for log segments to enhance the evidentiary effect of compliance auditing. At the same time, the audit log can be associated with device maintenance work orders, firmware version change records, and field environment change records to provide support for locating the root cause of the sideband leakage anomaly, such as determining whether the anomaly is related to a change in the power amplifier control strategy after a firmware upgrade, a change in heat dissipation conditions, or the access of a certain type of load.

[0069] Therefore, this solution utilizes the noise floor during adjacent channel idle periods as an indirect measurement of sideband leakage, and intensifies sampling during high-risk periods such as temperature rise changes or load surges. This allows it to cover intermittent over-limit scenarios that traditional spot checks struggle to cover, enabling timely detection of sideband leakage anomalies on-site without the need for external testing instruments. When an anomaly meets the triggering conditions, the gateway immediately issues a power backoff command, reducing transmission power and minimizing sideband energy leakage, thus suppressing the risk before it spreads. By recording key elements such as the anomaly occurrence time, duration, handling results, and device identification in the audit log, and linking them to the noise baseline version and monitoring sequence summary, the operations and maintenance team can review the anomaly occurrence conditions, the timeliness and effectiveness of the handling, and whether there are repeated triggers, thus forming a traceable and verifiable chain of compliance evidence.

[0070] In some cases, considering that the effectiveness of subcarrier whitelists in high-speed power line carrier communication in low-voltage distribution areas is highly dependent on the stability of line topology and impedance distribution, changes in frequency-selective fading characteristics and noise coupling paths after capacity expansion, phase line modification, branch line addition, or bridging adjustments can alter the whitelist. This can lead to a gradual mismatch in the whitelist established during the acceptance or optimization phase, typically manifesting as a slowdown after several months. However, this process is often gradual, and passive parameter tuning triggered by conventional service indicators is often delayed and involves repeated trial and error. This solution periodically injects ultra-low energy test sequences to map the line without significantly affecting normal services. The equivalent impedance matrix is ​​inverted using the response differences of the test sequences propagating between phase lines, neutral lines, and ground, thus transforming changes in topology and impedance distribution into a calculable and comparable impedance tomography representation. An impedance fingerprint database is established at the time of acceptance, binding the baseline impedance tomography to the then-effective subcarrier whitelist version. During subsequent operation, the similarity between the current impedance tomography and the fingerprint database samples is calculated. When a sudden change in the impedance tomography exceeds a threshold, the solution is applied. When the line impedance structure has changed significantly or entered an impedance pattern similar to a certain historical stage, rolling back to the historical whitelist version that is closest to the current impedance pattern can restore the matching of subcarrier selection and channel conditions more quickly, thus transforming passive parameter tuning into look-back based on topology changes. After the rollback, the fine-tuning mode is enabled and the subcarrier is filled in small steps to verify that the space can be further improved, so that the system can achieve an engineering balance between rapid recovery and continuous optimization. The comparison of bit error rate, group delay, throughput and energy consumption before and after the rollback forms an auditable maintenance evidence chain. Based on this, some examples also include a look-ahead self-healing rollback process based on transformer topology changes. This look-ahead self-healing rollback process includes: injecting a probe sequence of ultra-low energy into the low-voltage distribution line at a preset period, and inverting the equivalent impedance matrix between the phase line, neutral line, and ground based on the response of the probe sequence to generate a current impedance tomography; establishing an impedance fingerprint database at the acceptance time, which stores at least a baseline impedance tomography and a subcarrier whitelist version corresponding to the baseline impedance tomography; calculating the similarity between the current impedance tomography and the samples in the impedance fingerprint database to determine the closest historical whitelist version; automatically switching to the subcarrier whitelist of the closest historical whitelist version when the impedance tomography change corresponding to the similarity meets a preset threshold, and marking it as a rollback event triggered by topology changes; and enabling a fine-tuning mode within a preset observation period after the switch to gradually fill in a preset number of subcarriers and verify whether link performance is further improved, while simultaneously writing the comparison results of bit error rate, group delay, throughput, and energy consumption before and after the rollback into a maintenance report.

[0071] For example, when an edge node or distribution zone gateway arrives at a preset period, it injects an ultra-low energy probe sequence into the low-voltage distribution line without affecting normal services. The injection period of the probe sequence is preferentially selected during windows with low service load or when the scheduling layer can insert mapping time slots. Constraints are placed on the injection power, injection duration, injection frequency band coverage, and injection repetition number to ensure that the interference caused to service communication is controllable and negligible. The probe sequence can be designed as a sequence with good autocorrelation characteristics to enable robust response extraction at the receiving end. The gateway collects line response data simultaneously with the injection. The response data includes at least the amplitude response, phase response, or equivalent transfer function estimation results of the probe sequence at different frequency points or different time slices. It can also be combined with the gateway's measurement of the switching between different injection paths between the phase line, neutral line, and ground to enable the response data to distinguish the coupling between the phase line and the neutral line. The gateway performs inversion calculations based on the response data to generate an equivalent impedance matrix between the phase line, neutral line, and ground. The inversion calculation can adopt a parameter estimation method based on minimum error fitting, which maps the observed response to the equivalent circuit model or equivalent transmission model to obtain the estimated values ​​of the matrix elements, and outputs a quality label for the estimation results. For example, the reliability of the inversion is evaluated based on the residual size, effective frequency coverage, and environmental noise level. Subsequently, the gateway maps the equivalent impedance matrix into a current impedance tomography according to a preset visualization or feature method. The impedance tomography can include the impedance amplitude distribution, phase distribution, and structured feature vectors reflecting the location or degree of impedance abrupt changes at multiple frequency points, and stores them together with the mapping timestamp, injection parameters, and inversion quality label for subsequent similarity calculation with the fingerprint database. During the acceptance testing period of the distribution area or a stable period when network performance reaches the target threshold and whitelist optimization is completed, the gateway establishes an impedance fingerprint database. This database stores at least a baseline impedance tomography map and the corresponding subcarrier whitelist version. It may also store link performance statistics associated with that version as supporting evidence, such as the bit error rate, group delay quantile, throughput, and energy consumption per unit of service at that time. Each record in the impedance fingerprint database includes at least a record identifier, acquisition time, impedance tomography data or its characteristic representation, inversion quality identifier, whitelist version number, and whitelist content. The abstract and the scope of application of this version are described, which can describe the applicability of this version under specific load levels, specific noise backgrounds, or specific seasonal load conditions. To ensure the comparability of subsequent similarity calculations, the design of the trial sequence, the mapping frequency band range, the sampling bandwidth, and the inversion algorithm parameters at the acceptance time and during routine surveying should be consistent or meet a mapping relationship. If the parameters are adjusted, the gateway should record the parameter version in the fingerprint database and perform parameter consistency correction during similarity calculations or only compare within the same parameter version, thereby avoiding misjudgment rollback caused by changes in measurement caliber.After obtaining the current impedance tomography, the gateway reads candidate samples from the impedance fingerprint database and calculates the similarity between the current impedance tomography and each candidate sample to determine the closest historical whitelist version. In the specific implementation, the similarity calculation can be based on the structured feature vector of the tomography. The feature vector includes at least the statistical features of the impedance amplitude distribution at multiple frequency points, the statistical features of the impedance phase distribution, and features reflecting the degree of impedance abrupt change. Weights can be applied to features of different frequency bands to make it more sensitive to the effective operating frequency band of the carrier. The gateway calculates a similarity score for each sample and simultaneously checks the inversion quality label and the noise level of the mapping environment. If the quality of the current tomography is insufficient or the noise background is abnormal, the comparison result is marked as low confidence and the rollback decision can be delayed until the next mapping cycle for re-verification. When the comparison result is reliable, the gateway selects the sample with the highest similarity score as the closest historical version and outputs the corresponding whitelist version number and historical performance summary as rollback candidates. At the same time, several versions with high similarity rankings can be retained as alternatives for rapid replacement if the effect is not good after subsequent rollback. The gateway determines whether the impedance tomographic abrupt change meets a preset threshold based on the similarity calculation results. This preset threshold can be defined as the difference between the current tomographic map and the baseline tomographic map exceeding a certain threshold, or as a situation where the highest similarity historical sample has a high similarity to the current tomographic map but shows a significant difference from the baseline sample, thus indicating that the transformer area's impedance morphology has deviated from the applicable area of ​​the current whitelist version. When the abrupt change threshold is met, the gateway automatically switches to the subcarrier whitelist corresponding to the closest historical version. The switching process includes distributing the new whitelist to relevant communication entities and updating scheduling and modulation parameters, ensuring that subsequent carrier communication preferentially uses the whitelist. The subcarrier set is used, and the gateway generates and marks a rollback event triggered by a topology change. The rollback event includes at least the event occurrence time, the current tomographic identifier used for triggering, the threshold condition for the hit, the selected historical version number, the whitelist version number before the switch, and the similarity score, which are used to indicate that this rollback is not a random parameter tuning but a self-healing action driven by impedance morphology changes. To avoid frequent jitter switching, the gateway can require the mutation threshold to be continuously met for several consecutive mapping cycles before the rollback decision, or set a minimum hold time after the rollback, during which only fine-tuning is allowed and no large rollback is allowed again, thereby improving the stability of the project.After completing the whitelist rollback switch, the gateway initiates a fine-tuning mode within a preset observation period. This fine-tuning mode explores further performance improvements through small-step backfilling while maintaining the overall structure of the rollback version. Specifically, in each fine-tuning cycle, a preset number of candidate subcarriers are selected from the currently inactive subcarrier set for backfilling, bringing them into the temporarily available set. Within a controlled service window, the impact of backfilled subcarriers on bit error rate, group latency, throughput, and energy consumption is verified. The gateway establishes a test record for each backfilling operation. The test record includes at least the set of subcarrier identifiers backfilled, the load level during the test period, noise background indicators, performance statistics before and after backfilling, and the backfilling conclusions. If backfilling leads to a deterioration in the bit error rate or an increase in group latency, the backfilling is revoked and the system is restored to the stable set of the rollback version. If backfilling improves throughput and keeps the bit error rate and group latency within an acceptable range, the backfilling is solidified to the new whitelist incremental version. After the observation period ends or the stable conditions are met, the gateway compares and summarizes the bit error rate, group latency, throughput, and energy consumption before and after the rollback and before and after the fine-tuning. The comparison results, along with the rollback event markers, fault map similarity evidence, and fine-tuning test conclusions, are written into the maintenance report. This allows operations and maintenance personnel to directly view the rollback triggering reasons, the version adopted, the short-term recovery effect, and whether further optimization has been completed, thus forming a verifiable and traceable self-healing maintenance record.

[0072] In some cases, considering the different delay distribution characteristics, congestion sensitivity, and retransmission costs of high-speed power line carrier communication and high-speed radio frequency communication in a dual-mode communication architecture: Power line carrier communication relies on existing power lines for wide coverage and is economical, but it is susceptible to noise and impedance changes in the transformer area, and delay jitter and retransmission probability increase significantly during peak load periods; Radio frequency communication has the advantages of flexible coverage and faster first transmission, but it is affected by air interface competition, obstruction, and power constraints, and continuous high traffic occupation can cause congestion and acknowledgment delays. If the existing network only queues packets according to message length, port number, or simple priority, it often fails to reflect the semantic importance of the message service, resulting in unacceptable first packet delays and delivery risks for critical small packets such as over-limit alarms and remote control commands under the occupation of large-volume tasks such as firmware upgrades and log back. This solution shifts scheduling decisions from being driven by traffic volume to being driven by semantic constraints: edge nodes perform lightweight semantic discrimination on service packets, classifying them into semantic categories such as billing, remote control, over-limit alarms, and logs, and defining a set of verifiable service constraints for each semantic category, including maximum end-to-end latency, jitter threshold, maximum number of retransmissions, first transmission medium preference, and allowed cross-media reordering; based on this, edge nodes break down the time budget into executable budget parameters, constraining medium selection, uplink or downlink transmission cycles, and retransmission counts respectively, enabling the scheduler to arrange the transmission and retransmission order of the two media in the form of a cross-media schedule. For over-limit alarm messages, wireless radio frequency communication is used first for transmission to reduce the latency of the first packet. If the preset confirmation time limit is not met, a copy is sent via power line carrier communication to improve the reachability. For large-volume tasks, time slicing is used to break down continuous occupancy into multiple segments and intersperse them between alarm windows. This ensures that small packets of key semantics are sent and confirmed within the time budget without completely blocking large tasks. Ultimately, this improves the service level compliance rate of each semantic category and generates measurable statistics on the latency of the first packet and the compliance rate.Based on this, some examples also include a semantically driven cross-media time budget scheduling process, which includes: performing lightweight semantic discrimination on service packets at edge nodes to classify the service packets into semantic categories that include at least billing, remote control, over-limit alarms, and logs; defining a set of constraints for each semantic category, including maximum end-to-end latency, jitter threshold, maximum retransmission count, first transmission medium preference, and allowed cross-media reordering; and splitting the time budget into medium selection, uplink or downlink transmission period based on the constraint set. The system includes a budget parameter for the number of retransmissions; a cross-media schedule is generated based on the budget parameter to schedule the transmission and retransmission of high-speed wireless radio frequency communication and high-speed power line carrier communication. For over-limit alarm messages, high-speed wireless radio frequency communication is used first, and a copy is sent using high-speed power line carrier communication if the preset confirmation time limit is not met. The system also performs time slicing for large-volume tasks, dividing large-volume tasks into multiple segments and interspersing them between the transmission windows of the over-limit alarm messages to improve the service level compliance rate of each semantic category and record the compliance rate and first packet delay statistics of each semantic category.

[0073] For example, edge nodes perform lightweight semantic discrimination on service packets entering the scheduling queue to classify the service packets into semantic categories that include at least billing, remote control, over-limit alarms, and logs. This lightweight semantic discrimination can be implemented based on the application identifier field, service topic identifier, message format characteristics, reporting source device type, event code field, or a combination of key fields corresponding to the service protocol, and outputs a clear semantic category label while ensuring controllable computational overhead. In one possible implementation, the edge node maintains a semantic mapping rule table, which maps service identifiers to semantic categories and supports... Differentiated configurations are implemented based on distribution area or equipment type. For example, messages related to electricity metering cycle settlement are marked as billing messages, messages related to equipment execution control commands or switch control are marked as remote control messages, messages related to over-threshold events or over-limit status changes are marked as over-limit alarm messages, and messages related to operation logs and diagnostic information feedback are marked as log messages. After completing semantic discrimination, the edge node adds a semantic category identifier to each message, generates a unique message identifier, and records the timestamp of entering the queue. This enables subsequent cross-media time budget allocation and scheduling execution to be traceable and verified according to the semantic dimension. For each semantic category, edge nodes define a set of constraints including maximum end-to-end latency, jitter threshold, maximum retransmission count, initial transmission medium preference, and allowed cross-media reordering. Maximum end-to-end latency limits the longest allowed time from when a packet enters the scheduling queue to when it is acknowledged by the target. The jitter threshold limits the latency dispersion of packets of the same semantic category across multiple consecutive events. The maximum retransmission count limits the upper limit of retransmission overhead for this semantic category when resources are scarce. The initial transmission medium preference determines whether, under normal conditions, this semantic category should preferentially use high-speed radio frequency communication or high-speed power line carrier communication for the first transmission. Allowed cross-media reordering determines whether duplicate transmissions, order adjustments, and deduplication / merging are allowed between the two media. The edge node decomposes the time budget into budget parameters based on the aforementioned constraint set. These budget parameters include at least a medium selection parameter, an uplink or downlink transmission cycle parameter, and a retransmission count budget parameter. The medium selection parameter specifies the switching conditions between the preferred and alternative media for different semantic categories. The uplink or downlink transmission cycle parameter specifies the scheduling granularity and latest transmission time for that semantic category on the time axis. The retransmission count budget parameter specifies the maximum number of retransmission rounds allowed when an acknowledgment has not arrived and the waiting time limit for each round. To facilitate engineering implementation, the edge node can manage the budget parameter table in a versioned manner and allow differentiated configuration based on the area congestion level, historical success rate, and wireless coverage quality, ensuring that the budget remains achievable under different area conditions.The edge node scheduler generates a cross-media schedule based on budget parameters. This schedule is used to arrange the transmission windows, acknowledgment waiting windows, and necessary retransmission windows for high-speed radio frequency communication and high-speed power line carrier communication on a unified time axis. Specifically, it includes reserving periodic or event-triggered transmission slots for each semantic category and determining the queue of transmittable messages and allowed retransmission actions within each slot. During execution, the scheduler records the initial transmission medium, initial transmission time, acknowledgment waiting deadline, and remaining retransmission budget for each message, and updates the message status based on the acknowledgment receipt, thereby ensuring that the scheduling process is traceable and statistically verifiable. For over-limit alarm messages, the scheduler prioritizes high-speed radio frequency communication for the first transmission according to the initial transmission medium preference and sets a shorter time limit for it. To ensure the first packet delay, a confirmation waiting period is set. If no confirmation is received within the preset confirmation period, the scheduler sends a copy of the same message on the high-speed power line carrier communication link according to the allowed cross-media reordering rules. At the same time, the message carries a unique identifier for the receiving end or edge node to perform deduplication, thereby improving the alarm arrival probability without significantly increasing the alarm first packet delay. For other semantic categories, the scheduler arranges the sending and retransmission order according to their respective maximum delay and retransmission budget. For example, longer delays are allowed for billing messages, but higher delivery integrity is required. Log messages can be set with lower priority and can be sent after congestion delay, so that the cross-media schedule can coordinate the service requirements and resource overhead of different semantic categories within the same framework. When an edge node detects a large-volume task entering the queue, such as firmware upgrades, batch parameter distribution, or large-scale log back, the scheduler performs time slicing on the large-volume task, breaking it down into multiple segments and distributing them across a cross-media timetable for transmission. This avoids the large-volume task from continuously occupying a single medium for an extended period. In specific implementations, the scheduler defines segment size, segment transmission interval, and minimum yield window between segments for large-volume tasks, and binds the yield window to the transmission window of over-limit alarm messages. This ensures that whenever a large-volume task enters the alarm window or an alarm event is triggered, it is promptly sent to the next segment. The transmission of task segments is automatically paused or slowed down, prioritizing the release of media resources for the initial transmission and necessary retransmission of alarm messages. To ensure that large-volume tasks can still be completed within a reasonable time, the scheduler can increase the segment transmission density during low-alarm periods and allocate the segment carrying ratio between the two media based on the real-time congestion levels of the radio and the carrier, making the overall completion time of large-volume tasks controllable and preventing the continuous suppression of critical semantic messages. At the same time, the scheduler retains the segment sequence number and integrity verification information for each segment, ensuring that correct reassembly and integrity verification can still be performed at the receiving side under fragmentation and interleaved transmission conditions.During scheduling execution, edge nodes continuously collect and record the service level compliance rate and first packet latency statistics for each semantic category. The first packet latency statistics can be defined as the time from when a packet enters the queue to when the first transmission is completed or the first acknowledgment arrives. The compliance rate can be defined as the percentage of packets that meet the maximum end-to-end latency constraint and are successfully acknowledged within the statistical window. Further, jitter threshold compliance, retransmission ratio, and cross-media replica trigger ratio can be recorded as auxiliary statistics. Edge nodes group and summarize the statistical results by area, device type, or time period, and establish a correlation with the current budget parameter version. This allows operations and maintenance personnel to directly observe whether a certain semantic category meets the standards under certain conditions in a certain area and whether the compliance bottleneck comes from the first transmission medium or the retransmission budget. When the statistics show that a certain semantic category has been unqualified for a long time, the edge nodes can adjust the budget parameters of the corresponding semantic category based on the statistical results. For example, tightening or relaxing the acknowledgment waiting time limit, adjusting the first transmission medium preference, changing the allowed cross-media reordering strategy, or adjusting the large-volume task slice transfer window. This achieves continuous optimization driven by quantitative indicators and ensures that the adjustment of the scheduling strategy has an interpretable basis and a traceable version record.

[0074] The above describes the low-voltage power distribution line status monitoring method based on dual-mode communication in the embodiments of this application. The following describes the low-voltage power distribution line status monitoring system based on dual-mode communication in the embodiments of this application.

[0075] Please see Figure 2 This application describes an embodiment of a low-voltage distribution line status monitoring system based on dual-mode communication, which may include:

[0076] The acquisition unit 201 is used to acquire reference phase information on the transformer side and control multiple distribution terminals to send local voltage phase segments within a preset monitoring period. The reference phase information is used to characterize the phase reference of the grid-side voltage. The local voltage phase segment includes zero crossover time information or equivalent phase vector information of the terminal-side voltage.

[0077] The calculation unit 202 is used to align the reference phase information with the local voltage phase segments sent by each distribution terminal at the edge node, use least squares estimation to obtain the phase difference of each distribution terminal relative to the reference phase information, and generate a phase correction table based on the phase difference.

[0078] The correction unit 203 is used to automatically correct the phase label of each distribution terminal based on the phase correction table, regroup the in-phase broadcast or multicast domains, and reallocate the communication time slots corresponding to the multicast domains, so that the terminals whose multicast configuration fails due to the inconsistency between the phase label and the actual physical phase are pulled into the high-quality communication domain with consistent phase, thereby reducing the reporting interval jitter of the terminals and improving the multicast domain reuse efficiency.

[0079] above Figure 2 The low-voltage distribution line status monitoring system based on dual-mode communication in this application embodiment has been described from the perspective of modular functional entities. The following is a detailed description of the low-voltage distribution line status monitoring system based on dual-mode communication in this application embodiment from the perspective of hardware processing. Please refer to... Figure 3 One embodiment of the low-voltage distribution line status monitoring system 300 based on dual-mode communication in this application includes:

[0080] The system includes an input device 301, an output device 302, a processor 303, and a memory 304, wherein the number of processors 303 can be one or more. Figure 3 Taking a processor 303 as an example. In some embodiments of this application, the input device 301, output device 302, processor 303, and memory 304 can be connected via a bus or other means, wherein... Figure 3 Taking the example of a connection between China and Israel via a bus.

[0081] Specifically, the processor 303 executes the above steps by calling the operation instructions stored in the memory 304.

[0082] By calling the operation instructions stored in memory 304, processor 303 is also used to execute... Figure 1 Any of the methods in the corresponding embodiments.

[0083] Please see Figure 4 , Figure 4 A schematic diagram illustrating an embodiment of the electronic device provided in this application.

[0084] like Figure 4 As shown, this application provides an electronic device, including a memory 304, a processor 303, and a computer program 411 stored in the memory 304 and executable on the processor 303. When the processor 303 executes the computer program 411, it performs the above steps.

[0085] In practical implementation, when processor 303 executes computer program 411, it can achieve... Figure 1 Any of the corresponding implementation methods in the embodiments.

[0086] Since the electronic device described in this embodiment is the device used to implement a low-voltage power distribution line status monitoring system based on dual-mode communication in this application embodiment, those skilled in the art can understand the specific implementation method and various variations of the electronic device in this embodiment based on the method described in this application embodiment. Therefore, how the electronic device implements the method in this application embodiment will not be described in detail here. Any device used by those skilled in the art to implement the method in this application embodiment is within the scope of protection of this application.

[0087] Please see Figure 5 , Figure 5 This is a schematic diagram illustrating an embodiment of a computer-readable storage medium provided in this application.

[0088] like Figure 5 As shown, this embodiment provides a computer-readable storage medium 500 on which a computer program 511 is stored, which performs the above steps when executed by a processor.

[0089] By calling the operation instructions stored in memory 304, processor 303 is also used to execute... Figure 1 Any of the methods in the corresponding embodiments.

[0090] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for monitoring the status of low-voltage power distribution lines based on dual-mode communication, characterized in that, include: The reference phase information of the transformer side is obtained, and multiple distribution terminals are controlled to send local voltage phase segments within a preset monitoring period. The reference phase information is used to characterize the phase reference of the grid-side voltage, and the local voltage phase segment includes the zero crossover time information or equivalent phase vector information of the terminal-side voltage. At the edge nodes, the reference phase information is aligned with the local voltage phase segments transmitted by each distribution terminal. Least squares estimation is used to obtain the phase difference of each distribution terminal relative to the reference phase information, and a phase correction table is generated based on the phase difference. The reference phase information includes the zero-crossing time sequence of the transformer-side voltage, and the local voltage phase segments include the zero-crossing time sequence of the terminal-side voltage. The generation of the phase correction table based on the phase difference includes: the edge nodes perform time alignment on the zero-crossing time sequence to establish a time offset model of the terminal-side zero-crossing time relative to the grid-side zero-crossing time, and convert the time offset model into a phase difference to generate the phase correction table. The phase correction table automatically corrects the phase labels of each distribution terminal and regroups the in-phase broadcast or multicast domains. Simultaneously, it reallocates the communication time slots corresponding to the multicast domains. The phase correction table contains a correspondence between terminal identifiers and phase correction values. The phase correction values ​​are used to map the original phase label of the terminal to a corrected phase label. Regrouping the in-phase broadcast or multicast domains includes: assigning the terminal to a phase-consistent multicast domain based on the corrected phase label, and updating the broadcast or multicast parameters of the multicast domain to ensure that the in-phase broadcast or multicast reception conditions of the terminal are consistent with its actual physical phase.

2. The method according to claim 1, characterized in that, Also includes: After the regrouping and redistribution are completed, high-speed power line carrier communication is used to carry the local access links of at least some of the multiple power distribution terminals, and high-speed wireless radio frequency communication is used to provide redundant transmission links or anti-interference supplementary links for at least some of the multiple power distribution terminals, so as to monitor the status of the continuity and reliability of terminal reporting of low-voltage power distribution lines.

3. The method according to claim 2, characterized in that, The status monitoring of the continuity and reliability of terminal reporting for low-voltage power distribution lines includes: The statistical terminal reports the interval sequence within a preset monitoring window, and calculates the variance of the reporting interval jitter as a link quality indicator. After completing the automatic phase correction and the multicast domain regrouping and time slot reallocation, the link quality indicators before and after the update are compared. When the link quality indicators meet the preset improvement threshold, the regulatory conclusion that the phase mismatch correction is successful is output, and the corresponding terminal is marked as having recovered from the isolated terminal state.

4. The method according to any one of claims 1 to 3, characterized in that, Also includes: A compliance self-test process for passive sideband detection is performed at the gateway, the compliance self-test process including: recording the adjacent channel noise baseline used to characterize the noise level during adjacent channel idle periods; When a change in equipment temperature rise or a sudden change in load is detected, the sampling frequency during the adjacent channel idle period is increased or the sampling duration is extended to obtain the adjacent channel noise monitoring sequence. The adjacent channel noise monitoring sequence is compared with the adjacent channel noise baseline to determine whether there is an abnormality in the sideband leakage based on the change amplitude or rate of change of the noise floor.

5. The method according to claim 4, characterized in that, Also includes: When the result of the difference analysis meets the triggering condition for the sideband leakage anomaly, the gateway generates a sideband leakage anomaly event and issues a compliance handling instruction, which is used to trigger the target device to perform a transmit power backoff operation. The sideband leakage anomaly event will be written into the audit log. The audit log will include at least the time of the anomaly, the duration of the anomaly, the execution result of the transmit power rollback operation, and the corresponding device identifier, for subsequent compliance tracing and risk auditing.

6. A low-voltage power distribution line status monitoring system based on dual-mode communication, characterized in that, include: The acquisition unit is used to acquire reference phase information on the transformer side and control multiple distribution terminals to send local voltage phase segments within a preset monitoring period. The reference phase information is used to characterize the phase reference of the grid-side voltage, and the local voltage phase segment includes zero crossover time information or equivalent phase vector information of the terminal-side voltage. A calculation unit is used to align the reference phase information with the local voltage phase segments transmitted by each distribution terminal at the edge node, obtain the phase difference of each distribution terminal relative to the reference phase information using least squares estimation, and generate a phase correction table based on the phase difference. The reference phase information includes a zero-crossing time sequence of the transformer-side voltage, and the local voltage phase segments include a zero-crossing time sequence of the terminal-side voltage. Generating the phase correction table based on the phase difference includes: the edge node performing time alignment on the zero-crossing time sequence to establish a time offset model of the terminal-side zero-crossing time relative to the grid-side zero-crossing time, and converting the time offset model into a phase difference to generate the phase correction table. The correction unit is used to automatically correct the phase label of each distribution terminal based on the phase correction table, regroup the in-phase broadcast or multicast domains, and reallocate the communication time slots corresponding to the multicast domains. The phase correction table contains the correspondence between terminal identifiers and phase correction amounts. The phase correction amounts are used to map the original phase label of the terminal to the corrected phase label. The regrouping of the in-phase broadcast or multicast domains includes: classifying the terminal into a phase-consistent multicast domain according to the corrected phase label, and updating the broadcast or multicast parameters of the multicast domain to make the in-phase broadcast or multicast reception conditions of the terminal consistent with its actual physical phase.

7. An electronic device, characterized in that, The electronic device includes at least one processor and at least one memory connected to the processor, wherein the processor is used to call program instructions in the memory to execute the low-voltage power distribution line status monitoring method based on dual-mode communication as described in any one of claims 1 to 5.

8. A storage medium, characterized in that, The storage medium includes a stored program, wherein, when the program is executed, it controls the device where the storage medium is located to perform the low-voltage power distribution line status monitoring method based on dual-mode communication as described in any one of claims 1 to 5.

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