Power supply communication method and device based on power line carrier communication

Abstract

The invention discloses a power supply communication method and device based on power line carrier communication, and relates to the technical field of power supply communication. Problems of signal attenuation, insufficient anti-interference capability, insufficient stability of power supply communication, insufficient intelligent path switching capability and the like exist in the prior art. According to the method, high-sampling-rate PSD analysis, STFT and LSTM are adopted to predict noise power time sequence data, and a noise-load rate coupling model is established; secondly, based on a transmission line theory, researching channel time-varying characteristics, calculating signal reflection and multipath effects, and calculating channel coherence time through a sliding window; for signal attenuation, low, medium and high frequency band models are respectively established, path attenuation is calculated, and channel capacity is optimized; and finally, through real-time stability analysis, short-term and long-term SNR stability is calculated, and path selection is optimized in combination with a load rate, so that communication quality is ensured. And through integration of channel modeling, time-varying analysis and path optimization, the reliability and stability of power line carrier communication are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power supply communication, and particularly to a power supply communication method and device based on power line communication. Background Technique

[0002] The power supply communication method based on power line communication (PLC) is a technology that uses power lines to simultaneously transmit electrical energy and data signals. Its background mainly stems from the power system's demand for efficient and economical communication methods. With the development of smart grids, power line communication has been widely used in fields such as power metering automation, remote meter reading, smart home control, and street lamp management due to its advantage of not requiring additional communication line laying. This technology modulates high-frequency carrier signals and superimposes them on the power line power frequency current, using the existing power infrastructure to achieve data transmission, significantly reducing the deployment cost.

[0003] However, this method still has the following main defects:

[0004] Insufficient signal attenuation and anti-interference ability. In low-voltage distribution networks, dynamic changes in loads will cause impedance mutations, affecting signal propagation quality and reducing communication reliability. There are pulse noises, radio broadcast interferences, and transient interferences of household appliance switches caused by power frequency currents in power lines. These noises will reduce the signal-to-noise ratio and degrade communication quality. During peak electricity consumption periods, due to the decrease in impedance, signal attenuation intensifies, resulting in unstable communication links.

[0005] Blocking effect of distribution transformers, which limits the communication coverage. Due to the blocking effect of distribution transformers on high-frequency carrier signals, the carrier communication range is usually limited within a single transformer area, and direct communication across transformer areas cannot be achieved. Traditional solutions require the deployment of additional relay devices, increasing system complexity and operation and maintenance costs.

[0006] Insufficient stability and intelligent path switching ability of power supply communication. The path selection method is difficult to adapt to complex power grid environments and is prone to communication interruptions. It is unable to dynamically adjust the communication path according to channel quality, resulting in unstable data transmission. Summary of the Invention

[0007] The purpose of the present invention is to propose a power supply communication method and device based on power line communication in order to solve the problems mentioned in the above background technique.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] In a first aspect, the present invention provides a power supply communication method based on power line communication, which is characterized by including:

[0010] S1: Conduct power line carrier communication stability analysis, specifically:

[0011] S101: Conduct channel characteristic modeling correlation analysis to establish a model;

[0012] S102: Calculate real-time stability and attenuation values to obtain instantaneous SNR, equivalent distance attenuation A equiv Short-term time-domain stability S time and long-term time-domain stability S freq ;

[0013] S2: Process power supply communication, obtain attenuation values and real-time stability values for processing:

[0014] S201: Conduct path priority dynamic analysis:

[0015] S211: Input parameters: real-time stability value Stability Score , short-term stability S time and long-term stability S freq weighted and obtained, attenuation value A equiv equivalent distance attenuation value calculated by S1, path load rate: grid load rate of the current path; then conduct path analysis to obtain path status value Path Score ;

[0016] S212: Set path switching logic: Path of the current path Score is lower than the threshold; burst pulse noise is detected; channel coherence time < 1ms; select the path with the highest Path Score from the alternative path library; alternative path generation rule: physically topologically adjacent nodes;

[0017] S202: Conduct signal strengthening: Dynamically adjust signal parameters or enable relays according to attenuation values and channel status to ensure communication reliability;

[0018] S221: Adaptive modulation and power allocation: Dynamically switch modulation methods according to instantaneous SNR: When SNR > 20dB: Enable high-order modulation; When 10dB < SNR < 20dB: Switch to QPSK; When SNR < 10dB: Degrade to BPSK; Conduct dynamic power allocation: Inversely deduce the optimal power spectral density P(f) according to the Shannon formula, and proportionally increase the power for subcarriers with attenuation > 30dB;

[0019] S222: Enable relay and PCL communication module, conduct relay and encrypted transmission Relay trigger condition: equivalent attenuation A equiv>60 dB / km, no available high-Score path in the path scoring library; start the nearest PCL relay module and perform data segment encryption: original data → AES-256 encryption → fragmented into short messages, relay transmission protocol: the relay node receives the encrypted data, appends CRC check and then forwards it; if the target node does not respond, enable "relay relay".

[0020] In a second aspect, the present invention provides a power supply communication device based on power line carrier communication, including: a channel construction noise separation module, a channel variation adjustment module, a channel attenuation frequency optimization module, a stable attenuation calculation module, a path selection switching module, and a communication optimization intelligent adjustment module;

[0021] The channel construction noise separation module analyzes the coupling relationship between noise and grid load through high-sampling-rate power spectrum analysis and LSTM prediction of noise time series, and optimizes the anti-interference ability;

[0022] The channel variation adjustment module calculates the multipath attenuation and coherence time, and uses an adaptive equalizer to suppress inter-symbol interference and improve communication stability;

[0023] The channel attenuation frequency optimization module establishes attenuation models for different frequency bands, dynamically optimizes the transmit power and subcarrier modulation, and improves the channel capacity;

[0024] The stable attenuation calculation module calculates the channel gain, transmit power, and the impact of environmental noise, eliminates impulse noise, and analyzes the line aging situation;

[0025] The path selection switching module calculates the path score and dynamically selects the optimal communication path according to the stability value, attenuation value, and load rate;

[0026] The communication optimization intelligent adjustment module optimizes the power supply communication based on the channel characteristics, dynamically manages the path, and adapts the device to enhance the anti-interference ability.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] 1. The present invention accurately monitors the background noise through high-sampling-rate power spectrum analysis and time-frequency analysis methods (such as STFT), and uses the LSTM neural network to predict the temporal change of noise power, enabling the communication system to respond to noise mutations in advance. In addition, by analyzing the coupling relationship between the grid load rate and noise, the system can make dynamic adjustments during peak electricity consumption periods to ensure communication stability. This mechanism can significantly reduce the impact of impedance mutations caused by the start and stop of household appliances and improve the reliability of data transmission.

[0029] 2. The present invention combines transmission line theory to establish a time-varying characteristic model of the channel, predicts the change of the channel frequency response, and optimizes the channel resource allocation through multipath effect analysis. In particular, based on the real-time calculation of the channel coherence time, the system can adaptively adjust the equalizer (such as the LMS or RLS algorithm) under high time-varying conditions, effectively suppressing inter-symbol interference (ISI). In addition, the OFDM technology is adopted to preferentially utilize high-frequency resources in short-distance communication, while adjusting the power allocation to the low-frequency band in long-distance communication to maximize the channel capacity, thereby improving the overall communication efficiency.

[0030] 3. The present invention calculates Stability by comprehensively considering short-term and long-term stability indicators Score , and calculates Path by combining the equivalent attenuation value and the grid load rate Score , thereby dynamically selecting the optimal path for communication. When it detects a decrease in channel quality or excessive load, the system can automatically trigger a path switch based on Path Score and select the optimal alternative path to avoid communication interruption. In addition, by monitoring the long-term change of the channel through the rolling mean, the aging problem of the line can be detected in advance and a maintenance warning can be triggered to ensure the long-term stable operation of the power supply communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] For the convenience of those skilled in the art to understand, the present invention will be further described below in conjunction with the drawings.

[0032] Figure 1 FIG. is a flowchart of the method steps of the present invention.

[0033] Figure 2 FIG. is a block diagram of the device principle of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0035] It should be understood that the terms "comprising" and "including" used in the specification and claims of this disclosure indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their combinations.

[0036] It should also be understood that the terms used in this disclosure specification are merely for the purpose of describing specific embodiments and are not intended to limit the disclosure. As used in this disclosure specification and the claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms. It should be further understood that the term "and / or" used in this disclosure specification and the claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0037] Please refer to Figure 1 As shown, the present invention provides a power supply communication method based on power line carrier communication, including:

[0038] S1: Conduct a stability analysis of power line carrier communication, specifically:

[0039] S101: Conduct a channel characteristic modeling correlation analysis:

[0040] S111: Analyze the influence of noise interference on coupling: It should be noted that the start and stop of household appliances (such as refrigerators and air conditioners) will cause impedance mutations, resulting in broadband background noise (10 kHz - 30 MHz). The power of this noise is positively correlated with the power grid load rate. Therefore, it is necessary to conduct synchronous monitoring in combination with the power consumption period (such as peak hours in the morning and evening) to establish a time-dependent model;

[0041] Monitor the background noise PSD (power spectral density) through a high-sampling-rate power spectrum analyzer (or software radio), and the time resolution is recommended to be set at the second level to capture mutation characteristics;

[0042] Conduct data analysis: Calculate the mean and variance of PSD in different time periods, and extract the characteristic peak power spectral density (PSD). Calculation process: Select a suitable time window, such as 1 second, 5 seconds, 10 seconds, etc., to divide the data time period; perform FFT transformation on each time period to calculate PSD (using the Welch method or directly using FFT); calculate the mean and variance of PSD in different time periods to measure the stability of the noise signal; identify the characteristic peak (local maximum), and threshold method or peak detection algorithm (such as the findpeaks function) can be used; Mathematical formula: Where X(w) is the Fourier transform of the signal, and T is the time window length;

[0043] Analyze the change pattern of noise over time through STFT: Select a suitable window function (such as Hanning window, Hamming window), calculate the short-time Fourier transform, and obtain the time-frequency matrix: Among them, X(t,f) is the time-frequency matrix after STFT transformation, representing the intensity of the frequency f component at time t; x(n) is the original time-domain signal; w(n-t) is the window function (such as Hanning window, Hamming window), which is used to intercept the local signal so that only local data is analyzed for each transformation; e -j2πfn The exponential term of the Fourier transform, representing the spectral analysis of each short time period;

[0044] Model establishment: Prediction of the noise power time series. A time series dataset of the noise power is constructed through an LSTM neural network, and the training set and test set are divided; Design an LSTM network (input layer - hidden layer - output layer); After training, it is used to predict the noise power curve: h t =σ(W h x t +U h h t-1 +b h )

[0045] Establish a noise-load rate coupling relationship model: Select the grid load rate data, perform a correlation analysis with the noise data, through the correlation coefficient calculation formula: And observe the influence of the load rate on the noise;

[0046] Use long-term data to adjust the model parameters: Calculate the model prediction error: Among them: y true is the true value, y pred is the model predicted value, N is the number of samples. It should be noted that: RMSE is applicable to situations sensitive to large errors and will amplify the influence of large errors;

[0047] Mean absolute error: MAE is applicable to measuring the overall error size and is not sensitive to extreme errors; Obtain RMSE and MAE, compare the errors of different models, and select the optimal model;

[0048] For different models, there are different hyperparameters that need to be adjusted: Adopt LSTM (Long Short-Term Memory network), and obtain the key parameters: Learning Rate: Affects the model convergence speed; Number of hidden layer units (Hidden Units): Affects the learning ability of the model; Time step (Time Steps): Determines how many past data points the model considers at one time; Select the optimal hyperparameters through random search or Bayesian optimization;

[0049] Finally, perform cross-validation to improve the model stability; Adopt K-fold cross-validation, divide the data into K parts, train with K - 1 parts each time, and the remaining 1 part for testing; Calculate the average error of all folds to improve the model robustness.

[0050] S112: Deepen the dynamic root cause of channel time-variation:

[0051] Based on the transmission line theory, establish a signal reflection coefficient model at impedance mismatches such as distribution transformers, branch nodes, and load access points, and accurately calculate the amplitude attenuation and delay spread of multipath signals; in a typical low-voltage power grid, the multipath delay spread ranges from 1 to 5 μs, and for each additional branch node, the number of multipaths approximately doubles; combine the power grid topology (such as the number of branches and the difference in line lengths) and load characteristics to predict the notch position and depth (up to 20 - 30 dB) of the channel frequency response, and dynamically generate the channel transfer function H(f,t);

[0052] Perform dynamic calculation of the coherence time: Use a sliding time window (typical value 1 second) to calculate the correlation coefficient of the channel impulse response (CIR) in real time. When the correlation coefficient is lower than a threshold (such as 0.9), it is determined that the channel has changed significantly and the channel estimation needs to be updated; if the channel coherence time is less than 10 times the symbol period (for example, when the OFDM symbol period is 100 μs, the coherence time < 1 ms), then automatically enable an adaptive equalizer (such as the LMS or RLS algorithm) to suppress inter-symbol interference (ISI).

[0053] S113: Perform frequency-domain - distance joint model allocation of attenuation:

[0054] Perform piecewise frequency attenuation model allocation:

[0055] For the low-frequency band (frequency band < 1 MHz), use the linear attenuation model α(f) = k1×f + k2, where k1 ≈ 0.1 dB / km / MHz, which is suitable for low-frequency signal transmission of distribution cables;

[0056] For the high-frequency band (frequency band > 10 MHz), due to the skin effect and increased dielectric loss, use the exponential attenuation model α(f) = e af + b, where a ≈ 0.15 / MHz, to accurately describe the fast attenuation characteristics of high-frequency signals;

[0057] For the transition band (frequency band 1 - 10 MHz), based on measured data, use cubic spline interpolation (Spline) or polynomial fitting methods to achieve smooth transition and ensure model continuity;

[0058] Adaptive frequency band allocation according to distance: When the short-distance transmission is less than 300 meters, make full use of the wide frequency band resources of the high frequency band (10 - 30 MHz), adopt OFDM technology to dynamically allocate subcarriers, and improve the transmission rate; When the transmission distance is medium to long distance (300 - 500 meters), dynamically adjust the power allocation of high and low frequency bands according to the real-time channel measurement results, and give priority to ensuring the communication quality of the low frequency band (<1 MHz); When the transmission distance is long distance (500 meters), the high frequency signal attenuation exceeds 80 dB, and the channel capacity is dominated by the low frequency band. At this time, turn off the high frequency subcarriers and concentrate the power on the low frequency band to enhance the signal coverage;

[0059] Based on the Shannon formula, dynamically calculate the channel capacity C: where, H(f): Channel frequency response, jointly determined by the attenuation model α(f) and multipath effect, P(f): Transmit power spectral density, N(f): Noise power spectral density (including background noise, impulse noise, etc.). By optimizing the transmit power spectral density P(f) and subcarrier modulation method (such as QPSK, 16-QAM) in real time, maximize the channel capacity.

[0060] S102: Perform real-time stability and attenuation value calculation, and perform physical association using instantaneous SNR calculation: where, H(f)| 2 reflects the channel gain, which is directly related to line attenuation and multipath superposition; P tx is the transmit power, limited by EMC regulations (such as CISPR 22 limits ≤ -50 dBm / Hz below 30 MHz); If burst impulse noise (such as switch action) is detected, the contaminated subcarriers need to be temporarily excluded in the SNR calculation.

[0061] S121: Calculate the attenuation value: Obtain the physical decomposition of the frequency domain attenuation A(f) formula:

[0062] A(f) = -10log2|H(f)| 2 ;

[0063] Analyze the attenuation components to obtain conductor loss (proportional to the square root of frequency (skin effect dominates, )) and dielectric loss (proportional to frequency (polarization loss of cable insulation material, ));

[0064] Example: When the frequency band is less than 1 MHz, then A(f) = 0.02f + 2 dB / km (linear model); When the frequency band is greater than 10 MHz, then A(f) = 0.5e 0.1f dB / km (exponential model); It should be noted that: In the engineering application of equivalent distance attenuation A equiv ​Frequency selection f max Logic: Take the highest operating frequency of the system (such as 30 MHz), as its attenuation is the largest, which determines the limit distance of the link; if there are resonance points in the line (such as attenuation peaks caused by impedance mismatch), it is necessary to avoid and select the actual passband edge frequency; when A equiv > 60 dB / km, it is necessary to deploy repeaters (one level every 300 - 500 meters).

[0065] S122: Analyze the short-term time-domain stability, set a sliding window, and the window length matches the channel coherence time (such as a 10 ms window to track impedance mutations caused by the start and stop of household appliances); the standard deviation σSNR reflects the intensity of SNR fluctuations. If it exceeds the threshold (such as σ SNR > 5 dB), it is determined to be unstable; then perform coefficient of variation normalization processing: S time = 1 - (μ SNR / σ SNR ); when μ SNR < 10 dB, slight fluctuations will cause S time to drop sharply, and it is necessary to comprehensively judge in combination with the absolute SNR value;

[0066] Analyze the long-term time-domain stability, assign higher weights to the frequency bands where the control signals are located (such as the smart meter heartbeat signals are concentrated in CENELEC - A Band 3 - 95 kHz); the weights of the high-order modulation frequency bands (such as the subcarriers used by 64QAM) are doubled because they are more sensitive to SNR; long-term statistics (such as 24-hour rolling average) are used to detect line aging: if S freq continues to drop by 0.1 / week, trigger a maintenance warning.

[0067] S2: Process the power supply communication, obtain the attenuation value and the real-time stability value for processing:

[0068] S201: Perform dynamic analysis of path priority:

[0069] S211: Input parameters: The real-time stability value Stability Score , which is weighted by the short-term stability S time calculated by S1 and the long-term stability S freq . The formula is: Stability Score = 0.6 × S time + 0.4 × S freq , (the weights are adjusted according to the application scenario, such as smart meters pay more attention to long-term stability), the attenuation value A equiv the equivalent distance attenuation value calculated by S1, and the path load rate: the grid load rate of the current path (such as reducing the priority when the load rate > 80% during peak hours in the morning and evening); perform path analysis, and the formula is: Path Score = Stability Score×e^(-0.1×A equiv )×(1 - Load Factor ), where Load Factor is the "busyness degree" of the power grid line, usually ranging from 0 to 1 (or 0% to 100%); Path Score is the path coefficient.

[0070] S212: Set path switching logic:

[0071] Trigger condition: The Path of the current path Score is lower than the threshold (such as <0.7); sudden pulse noise is detected (such as the SNR instantaneously drops > 10dB due to the switching action); the channel coherence time < 1ms (too high time variability);

[0072] Switching action: Select the path with the highest Path Score from the alternative path library; Alternative path generation rule: Physically adjacent nodes in the topology (such as adjacent electric meters, branch lines); Avoid the lines passing through high - noise devices (such as air conditioners, frequency converters); Prefer the short path directly connected to the distribution transformer;

[0073] Case: The smart meter A sends data to the concentrator. The current path passes through a line with a load rate of 90% (load factor = 0.9), and it is detected that the start - stop of the air conditioner causes S time = 0.5; Calculate:

[0074] Stability Score = 0.6×0.5 + 0.4×0.8 = 0.62

[0075] A equiv = 45dB / km (medium - long distance line)

[0076] Path Score = 0.62×e^(-0.1×45)×(1 - 0.9) ≈ 0.62×0.011×0.1 ≈ 0.00068;

[0077] Path Score is much lower than the threshold 0.7, triggering path switching; Select the alternative path: The relay path through the adjacent electric meter B (load rate 60%, A equiv = 30dB / km), the new Path Score ≈ 0.82, and the switching is successful.

[0078] S202: Perform signal strengthening: Dynamically adjust signal parameters or enable relays according to the attenuation value and channel state to ensure communication reliability.

[0079] S221: Adaptive modulation and power allocation:

[0080] Modulation mode adjustment: When SNR > 20dB: Enable high-order modulation (64-QAM) to improve transmission efficiency; When 10dB < SNR < 20dB: Switch to QPSK to balance rate and reliability; When SNR < 10dB: Degrade to BPSK, sacrificing rate for robustness;

[0081] Perform dynamic power allocation: Reverse-derive the optimal power spectral density P(f) according to the Shannon formula: P(f) = max{(2^(C_target / B) - 1) × N(f) / |H(f)| 2 , P_EMC}, (P_EMC is the regulatory limit, such as CISPR 22); For subcarriers with attenuation > 30dB (such as > 10MHz), increase the power proportionally (not exceeding the EMC limit).

[0082] S222: Relay and PCL communication module enabled:

[0083] Relay trigger conditions: Equivalent attenuation A equiv > 60dB / km (such as line length > 500 meters), and there is no available high-Score path in the path scoring library;

[0084] Relay operation process: Start the nearest PCL (Power Line Communication) relay module (such as within 300 meters), perform data segmentation and encryption: Original data → AES-256 encryption → Fragmented into short messages (such as 128 bytes), Relay transmission protocol: The relay node receives the encrypted data, appends CRC check and then forwards; If the target node does not respond, enable "relay relay" (multi-hop transmission);

[0085] Case: The photovoltaic inverter needs to upload power generation data to the grid dispatching center over a long distance (800 meters), and the main path A_equiv = 75dB / km;

[0086] Enhanced operations:

[0087] Z01: Detect A equiv > 60dB / km, automatically turn off high-frequency subcarriers (> 10MHz), and concentrate power in the low-frequency band (3 - 95kHz);

[0088] Z02: SNR = 8dB (low-frequency band), the modulation mode is forced to BPSK, and the data rate drops to 5kbps;

[0089] Z03: Enable two-level PCL relay: Inverter → Relay 1 (at 400 meters, A equiv = 40dB / km) → Relay 2 (at 800 meters) → Dispatching center; The data between relays is encrypted with AES-256, and each hop has a CRC check and retransmission mechanism;

[0090] The transmission success rate is increased from 30% in single-hop to 95% in multi-hop, and the latency increases by 200 ms (acceptable).

[0091] Please refer to Figure 2 As shown, the present invention further provides a power supply communication device based on power line carrier communication, including: a channel construction and noise separation module, a channel variation adjustment module, a channel attenuation and frequency optimization module, a stable attenuation calculation module, a path selection and switching module, and a communication optimization and intelligent adjustment module;

[0092] The channel construction and noise separation module models the channel characteristics of power line carrier communication, focusing on analyzing the coupling effect of noise interference; monitors the background noise PSD through a high-sampling-rate power spectrum analyzer, and calculates the noise characteristics by combining methods such as FFT and STFT; uses an LSTM neural network to predict the noise power time series, and establishes the coupling relationship between noise and grid load rate through correlation analysis to optimize the anti-interference ability of power line carrier communication;

[0093] The channel variation adjustment module analyzes the signal reflection phenomenon at impedance mismatches such as distribution transformers, branch nodes, and load access points based on the transmission line theory, and calculates the attenuation and delay spread of multipath signals; calculates the channel coherence time through a sliding time window. If the coherence time is lower than the threshold, an adaptive equalizer (such as LMS or RLS) is used to suppress inter-symbol interference and improve communication stability;

[0094] The channel attenuation and frequency optimization module establishes a signal attenuation model according to different frequency bands, including low-frequency linear attenuation, high-frequency exponential attenuation, and a smooth transition model in the range of 1 - 10 MHz; calculates the channel capacity based on the Shannon formula, combines the power grid topology structure and load characteristics, dynamically optimizes the transmit power spectral density and subcarrier modulation method, realizes the adaptive spectrum allocation of the communication system, and improves the transmission efficiency;

[0095] The stable attenuation calculation module calculates the physical correlation parameters through the instantaneous SNR, analyzes the influence of channel gain, transmit power, and environmental noise, and eliminates the interference of burst pulse noise; in terms of attenuation analysis, it separately analyzes the conductor loss and dielectric loss, and calculates the equivalent distance attenuation value A equiv , to determine the link limit distance. In addition, the short-term time-domain stability is evaluated through a sliding window method, and the line aging condition is monitored using a long-term statistical method;

[0096] The path selection and switching module calculates the path score Path based on the real-time stability value, attenuation value, and path load rate Score , for dynamically selecting the optimal communication path; when the score of the current path is lower than the threshold, or abnormal situations such as burst pulse noise are detected, the system automatically switches to the alternative path with the highest score to maintain the stability and reliability of communication;

[0097] The Tongyou intelligent adjustment module combines channel characteristics, attenuation conditions and stability analysis results to optimize the power supply and communication strategy; adopts a dynamic path management method to improve the reliability of power line communication, and conducts intelligent scheduling according to the load conditions to ensure that the communication link can achieve the best performance under different load conditions; in addition, the module also includes the adaptation and optimization of communication devices to enhance the stability and anti-interference ability of the overall system.

[0098] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the present invention to the specific implementation manners. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the relevant technical fields can understand and utilize the present invention well. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A power supply communication method based on power line carrier communication, characterized in that, Including: S1: Conduct power line communication stability analysis, specifically: S101: Conduct channel characteristic modeling correlation analysis to establish a model; S102: Calculate the real-time stability and attenuation value to obtain the instantaneous SNR and the equivalent distance attenuation A equiv Short-term time-domain stability S time and long-term time-domain stability S freq ; S2: Process power supply communication, obtain attenuation values and real-time stability values for processing: S201: Conduct path priority dynamic analysis: S211: Input parameters: real-time stability value Stability Score , short-term stability S calculated by S1 time and long-term stability S freq weighted to obtain the attenuation value A equiv equivalent distance attenuation value calculated by S1, path load rate: grid load rate of the current path; then perform path analysis to obtain the path status value Path Score ; S212: Set path switching logic: Path of the current path Score is lower than the threshold; burst pulse noise is detected; Channel coherence time < 1ms; Select Path from the alternative path library Score The highest path; alternative path generation rule: physically adjacent nodes in the topology S202: Conduct signal enhancement: Dynamically adjust signal parameters or enable relays according to attenuation values and channel states to ensure communication reliability; S221: Adaptive modulation and power allocation: Dynamically switch modulation methods according to instantaneous SNR: When SNR > 20dB: Enable high-order modulation; When 10dB < SNR < 20dB: Switch to QPSK; When SNR < 10dB: Degrade to BPSK; Conduct dynamic power allocation: Invert the optimal power spectral density P(f) according to the Shannon formula, and proportionally increase the power for subcarriers with attenuation > 30dB; S222: The relay and PCL communication module is enabled for relay and encrypted transmission. Relay trigger condition: equivalent attenuation A equiv > 60 dB / km and there is no available high-Score path in the path scoring library; start the nearest PCL relay module and perform data segmentation encryption: original data → AES-256 encryption → fragmented into short messages, relay transmission protocol: the relay node receives the encrypted data, appends CRC check and then forwards it; if the target node does not respond, enable "relay relay".

2. The power supply communication method based on power line carrier communication according to claim 1, wherein The specific process of conducting channel characteristic modeling correlation analysis to establish a model is as follows: S111: Analyze the influence of noise interference on coupling: Monitor the background noise PSD through a high-sampling-rate power spectrum analyzer, and it is recommended to set the time resolution at the second level to capture mutation characteristics; Obtain characteristic peaks through data analysis; Analyze the change pattern of noise over time according to STFT to establish a model; S112: Deepen the dynamic root cause of channel time-variation; S113: Conduct frequency-domain - distance joint model allocation of attenuation.

3. The power supply communication method based on power line carrier communication according to claim 2, wherein The specific process of analyzing the change pattern of noise over time according to STFT to establish a model is as follows: Analyze the variation pattern of noise over time through STFT: Select an appropriate window function, calculate the short-time Fourier transform, and obtain the time-frequency matrix: X(t,f) is the time-frequency matrix after STFT transformation; x(n) is the original time-domain signal; w(n-t) is the window function, e -j2πfn The exponential term of the Fourier transform; Model establishment: Prediction of the noise power time series. A time series dataset of the noise power is constructed through an LSTM neural network, and the training set and test set are divided; the LSTM network is designed; after training, it is used to predict the noise power curve: h t = σ(W h x t + U h h t-1 + b h ) Establish a noise-load rate coupling relationship model: Select the power grid load rate data and conduct a correlation analysis with the noise data. Through the correlation coefficient calculation formula: Use long-term data to adjust the model parameters: Calculate the model prediction error: y true is the true value, y pred is the model predicted value, N is the number of samples, and the mean absolute error: Obtain RMSE and MAE, compare the errors of different models, and select the optimal model; Adjust different models: Adopt LSTM and obtain key parameters: learning rate; number of hidden layer units; Select the optimal hyperparameters through random search; Finally, conduct cross-validation to improve model stability; Adopt K-fold cross-validation, divide the data into K parts, train with K - 1 parts each time, and the remaining 1 part for testing; Calculate the average error of all folds to improve model robustness.

4. A power supply communication method based on power line carrier communication according to claim 2, characterized in that The specific process of deepening the dynamic root cause of channel time-variation is as follows: Based on the transmission line theory, establish a signal reflection coefficient model at impedance mismatches of distribution transformers, branch nodes, and load access points, and accurately calculate the amplitude attenuation and delay spread of multipath signals; In the low-voltage power grid, the multipath delay spread range is 1 - 5μs, and for each additional branch node, the number of multipaths approximately doubles; Combine the power grid topology structure and load characteristics to predict the notch position and depth of the channel frequency response, and dynamically generate the channel transfer function H(f,t); Conduct dynamic calculation of coherence time: Adopt a sliding time window to calculate the correlation coefficient of the channel impulse response in real time. When the correlation coefficient is lower than the threshold, it is determined that the channel has changed significantly, and update the channel estimation; If the channel coherence time is less than 10 times the symbol period, automatically enable the adaptive equalizer.

5. A power supply communication method based on power line carrier communication according to claim 2, characterized in that The specific process of conducting frequency-domain - distance joint model allocation of attenuation is as follows: Conduct segmented frequency attenuation model allocation: Adopt a linear attenuation model in the low-frequency band; Adopt an exponential attenuation model in the high-frequency band; In the transition section, based on measured data, use cubic spline interpolation to achieve smooth transition; Adaptive frequency band allocation according to distance: When the short-distance transmission is less than 300 meters, make full use of the wide frequency band resources of the high frequency band and adopt OFDM technology to dynamically allocate subcarriers; when the transmission distance is medium to long-distance transmission, dynamically adjust the power allocation between the high and low frequency bands according to the real-time channel measurement results to ensure the communication quality of the low frequency band; when the transmission distance is long-distance transmission, the high-frequency signal attenuation exceeds 80 dB, and the channel capacity is dominated by the low frequency band. At this time, turn off the high-frequency subcarriers and concentrate the power on the low frequency band to enhance the signal coverage; Dynamically calculate the channel capacity based on the Shannon formula.

6. A power supply communication method based on power line carrier communication according to claim 1, characterized in that, Performing real-time stability and attenuation value calculations to obtain the instantaneous SNR and the equivalent distance attenuation A equiv Short-term time-domain stability S time and long-term time-domain stability S freq The specific process is as follows: Physical association using instantaneous SNR calculation: H(f)| 2 reflects the channel gain and is directly related to line attenuation and multipath superposition; P tx is the transmit power; If burst pulse noise is detected, temporarily exclude the contaminated subcarriers in the SNR calculation; Calculate the attenuation value: Obtain the formula for the frequency-domain attenuation A(f) and perform a physical decomposition: A(f) = -10log2|H(f)| 2 Analyze the attenuation components to obtain conductor loss and dielectric loss; Analyze the short-term time-domain stability, set a sliding window, and match the window length with the channel coherence time; the standard deviation σSNR reflects the intensity of SNR fluctuations, and if it exceeds the threshold, it is determined to be unstable; perform coefficient of variation normalization: S time = 1 - (μ SNR / σ SNR ); when μ SNR < 10 dB, slight fluctuations will cause S time to drop sharply, and make a comprehensive judgment in combination with the absolute SNR value; Analyze the long-term time-domain stability and assign higher weights to the frequency bands where the signals are located; Double the weight of the high-order modulation frequency band; Long-term statistics are used to detect line aging: If S freq continuously decreases by 0.1 / week, a maintenance warning is triggered.

7. A power supply and communication device based on power line carrier communication, characterized in that, Applied to implement a power supply communication method based on power line carrier communication according to any one of claims 1-6. The device includes: a channel construction and noise separation module, a channel variation and modulation module, a channel attenuation and frequency optimization module, a stability and attenuation calculation module, a path selection and switching module, and a communication optimization and intelligent adjustment module; The channel construction and noise separation module analyzes the coupling relationship between noise and grid load through high-sampling-rate power spectrum analysis and LSTM prediction of noise time series, and optimizes the anti-interference ability; The channel variation and modulation module calculates the multipath attenuation and coherence time, and uses an adaptive equalizer to suppress inter-symbol interference and improve communication stability; The channel attenuation and frequency optimization module establishes attenuation models for different frequency bands, dynamically optimizes the transmission power and subcarrier modulation, and improves the channel capacity; The stability and attenuation calculation module calculates the channel gain, transmission power, and the impact of environmental noise, excludes pulse noise, and analyzes the line aging situation; The path selection and switching module calculates the path score and dynamically selects the optimal communication path according to the stability value, attenuation value, and load rate; The communication optimization and intelligent adjustment module optimizes the power supply communication based on the channel characteristics, dynamically manages the path, and adapts the device to enhance the anti-interference ability.

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