A method and system for detecting anti-interference of a power grid edge device beidou timing

Abstract

The application discloses a power grid edge device Beidou timing anti-interference detection method and system, relates to the power distribution equipment timing performance evaluation technical field, and includes the following steps: acquiring the reference performance evaluation result of the protection timing accuracy and sensitivity according to the second pulse synchronization deviation and Beidou signal power of the to-be-detected equipment under the reference working condition detection; acquiring the degradation performance evaluation result according to the second pulse synchronization deviation and satellite communication characteristics of the to-be-detected equipment under the suppression type interference working condition detection; calculating the time sequence deviation degree and the probability of deception attack according to the multi-modal time sequence characteristics of the to-be-detected equipment under the suppression type and deception type mixed interference working condition detection, so as to evaluate the deception protection capability of the to-be-detected equipment and acquire the deception protection evaluation result; and integrating the reference performance evaluation result, the degradation performance evaluation result and the deception protection evaluation result to acquire the final detection result. The application avoids the fragmentation of timing test, sensitivity test and anti-interference test, and improves the reliability and timeliness of the detection result.

Description

Technical Field

[0001] This application relates to the field of timing performance evaluation technology for power distribution equipment, specifically a method and system for detecting BeiDou timing anti-interference in power grid edge equipment. Background Technology

[0002] As a spatiotemporal infrastructure, the BeiDou Navigation Satellite System provides high-precision time synchronization services in core areas such as power dispatching, fault recording, and transmission line monitoring. Edge power grid devices, such as tower tilt monitoring, conductor temperature / icing monitoring, and UAV inspection terminals, typically incorporate Class I BeiDou time and positioning modules with microsecond-level accuracy. Because these devices are deployed in environments directly exposed to complex electromagnetic fields, the time synchronization modules often experience difficulties in satellite acquisition, time synchronization jumps, and time out-of-synchronization issues, thus affecting the stable operation of the power system. Therefore, it is necessary to test the accuracy, sensitivity, and interference resistance of the time synchronization modules. Conventional testing methods focus on the signal processing algorithm level, which improves the anti-interference capability of the time synchronization system but fails to establish a quantitative mapping relationship between time synchronization accuracy and interference power, and lacks reproducible laboratory testing methods, resulting in a lack of objective judgment criteria for the test results. On the other hand, outdoor testing with actual satellite signals is susceptible to environmental interference, leading to poor reproducibility and reliability of the test results. Furthermore, existing technologies typically perform timing accuracy testing, sensitivity testing, and anti-interference testing separately for different equipment and environments. This fragments the actual working logic of the timing module in power scenarios, failing to accurately reflect the module's comprehensive performance in complex electromagnetic environments and increasing testing costs due to process redundancy. In summary, a testing method that can be reproduced in an anechoic chamber environment and integrates testing items is needed to improve timing accuracy and the reliability and timeliness of anti-interference testing. Summary of the Invention

[0003] The purpose of this application is to address the problems of existing time synchronization accuracy testing methods, such as the lack of quantitative evaluation of the mapping relationship between interference and accuracy, reliance on solid-state environment, and discrete testing process, which lead to insufficient reliability and timeliness of testing results. This application proposes a method and system for anti-interference testing of BeiDou time synchronization for power grid edge devices. By constructing a full-process testing process that includes reference operating conditions, suppression interference operating conditions, and mixed interference operating conditions, the method avoids the separation of time synchronization testing, sensitivity testing, and anti-interference testing, thereby improving the reliability and timeliness of testing results.

[0004] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows: In a first aspect, embodiments of this application provide a method for detecting interference from BeiDou timing on power grid edge devices, the method comprising: Based on the second pulse synchronization deviation and BeiDou signal power of the device under test (DUT) under baseline operating conditions, the baseline performance evaluation results of protection timing accuracy and sensitivity are obtained; based on the second pulse synchronization deviation and satellite communication characteristics of the DUT under suppression interference conditions, the degradation performance evaluation results are obtained; based on the multimodal timing characteristics of the DUT under mixed suppression and deception interference conditions, the timing deviation and deception attack probability are calculated to evaluate the deception protection capability of the DUT and obtain the deception protection evaluation results; the baseline performance evaluation results, degradation performance evaluation results, and deception protection evaluation results are integrated to obtain the final test results.

[0005] Preferably, the step of obtaining the benchmark performance evaluation results of protection timing accuracy and sensitivity based on the second pulse synchronization deviation and BeiDou signal power of the device under test under benchmark operating conditions includes: performing radio frequency signal power calibration on the testing device to establish a power comparison table between the BeiDou test signal and the interference signal; calibrating the output power of the testing device based on the power comparison table to establish a benchmark operating condition of the fused physical field under electromagnetic shielding; performing basic testing of timing accuracy and sensitivity of the device under test according to the benchmark operating conditions, and collecting the second pulse synchronization deviation and BeiDou signal power collected during the testing process; obtaining the timing accuracy evaluation result based on the second pulse synchronization deviation; and obtaining the acquisition sensitivity and tracking sensitivity evaluation results based on the timing accuracy evaluation result and the BeiDou signal power; wherein the timing accuracy evaluation result, the acquisition sensitivity evaluation result, and the tracking sensitivity evaluation result form the benchmark performance evaluation result.

[0006] Preferably, the step of obtaining the timing accuracy assessment result based on the second pulse synchronization deviation includes: collecting the second pulse data output by the device under test under reference operating conditions; obtaining the second pulse synchronization deviation based on the time difference sequence between the second pulse data and the reference second pulse; calculating the statistical characteristics of the second pulse synchronization deviation; and if the statistical characteristics are less than or equal to the deviation threshold and the statistical characteristics are not greater than the time jump threshold, then it is determined that the timing accuracy of the device under test under reference operating conditions meets the standard requirements, and the timing accuracy assessment result is obtained.

[0007] Preferably, the step of obtaining the acquisition sensitivity and tracking sensitivity assessment results based on the timing accuracy assessment results and the BeiDou signal power includes: gradually reducing the radio frequency signal power of the detection device to adjust the reference operating condition, determining whether the device under test can reacquire the satellite signal and complete the first positioning after losing lock; if so, determining that the acquisition sensitivity of the device under test under the reference operating condition meets the standard requirements, and obtaining the acquisition sensitivity assessment result; and based on the acquisition sensitivity assessment result, dynamically adjusting the power of the reference operating condition to detect the tracking sensitivity of the device under test, and obtaining the tracking sensitivity assessment result.

[0008] Preferably, the step of dynamically adjusting the power of the reference operating condition based on the acquisition sensitivity evaluation result to detect the tracking sensitivity of the device under test and obtain the tracking sensitivity evaluation result includes: taking the minimum power required for the device under test to complete the first positioning as the acquisition sensitivity value, and adding it to a preset power to obtain a reference power for adjusting the radio frequency signal power; using the reference power as the starting power of the reference operating condition, and gradually reducing the radio frequency signal power to adjust the reference operating condition; based on the reference operating condition after power adjustment, monitoring whether the device under test can maintain positioning timekeeping within a continuous time period; if so, determining that the tracking sensitivity of the device under test under the reference operating condition meets the standard requirements, and taking the minimum power of the device under test to maintain positioning timekeeping as the tracking sensitivity value to obtain a tracking sensitivity evaluation result including the tracking sensitivity value.

[0009] Preferably, the degradation performance evaluation result is obtained based on the second pulse synchronization deviation and satellite communication characteristics of the device under test (DUT) under suppression interference conditions. This includes: performing out-of-band and in-band immunity tests on the DUT under suppression interference conditions for different interference types, including continuous wave, pulse interference, frequency sweep interference, modulation interference, and multi-tone interference; when performing out-of-band immunity tests, acquiring the second pulse synchronization deviation of the DUT and satellite communication characteristics including channel carrier-to-noise ratio and satellite visibility during the test; if both the second pulse synchronization deviation and the satellite communication characteristics meet the corresponding out-of-band immunity judgment rules, the DUT is judged to be qualified for out-of-band immunity; when performing in-band immunity tests, acquiring the second pulse data of the DUT during the test, and determining whether the in-band immunity of the DUT is qualified based on the timing mode of the DUT; and using the out-of-band and in-band immunity test results of the DUT as the degradation performance evaluation result.

[0010] Preferably, the step of acquiring the second pulse data of the device under test during the test and determining whether the in-band anti-interference of the device under test is qualified in combination with the timing mode of the device under test includes: the detection device increases the interference power in steps according to a preset value, and synchronously collects the second pulse data of the device under test during the change of interference power; when the interference power is within the range of the background noise power, if the change in the second pulse data per second does not exceed the preset value, the device under test is determined to be qualified for in-band anti-interference; or, if the device under test switches to a timekeeping state that maintains time synchronization through an internal clock, and the timekeeping error is lower than the industry standard error, the device under test is determined to be qualified for in-band anti-interference.

[0011] Preferably, the step of calculating the timing deviation and deception attack probability based on the multimodal timing characteristics of the device under test (DUT) under mixed suppression and deception interference conditions to evaluate the DUT's deception protection capability and obtain the deception protection assessment result includes: generating a phase-reversed zero-adjustment deception signal based on the carrier phase of the BeiDou satellite signal simulated by the detection device; injecting the zero-adjustment deception signal under the suppression interference condition to construct a mixed deception interference condition; collecting the second pulse synchronization deviation and deception attack field of the DUT under the mixed deception interference condition; if the DUT collects a deception attack field marked with a deception event and issues an alarm, and the time of occurrence of the deception event mark is less than the time when the second pulse synchronization deviation first exceeds the threshold, then it is preliminarily determined that the DUT has anti-deception capability; simultaneously, collecting the multimodal timing characteristics of the DUT under the mixed deception interference condition, using a neural network algorithm to calculate the timing deviation and deception attack probability to comprehensively evaluate the DUT's anti-deception capability and obtain the final deception protection assessment result.

[0012] Preferably, the step of using a neural network algorithm to calculate the timing deviation and spoofing attack probability to comprehensively evaluate the anti-spoofing capability of the device under test and obtain the final spoofing protection evaluation result includes: the multimodal timing features include AGC voltage sequence, time-frequency domain features, channel carrier-to-noise ratio, pseudorange, and carrier phase; based on an LSTM network, using the AGC voltage timing and channel carrier-to-noise ratio as input parameters, the timing deviation is obtained; based on a CNN network, using the time-frequency domain features, pseudorange, and carrier phase as input parameters, the spoofing attack probability is obtained; the timing deviation and the spoofing attack probability are weighted and summed to obtain the interference confidence level; if the time when the interference confidence level first exceeds the confidence level threshold is greater than the time when the spoofing event marker appears, the device under test is determined to have qualified anti-spoofing capability.

[0013] Secondly, embodiments of this application provide a BeiDou timing anti-interference detection system for power grid edge devices, including: The benchmark performance evaluation module is used to obtain benchmark performance evaluation results of protection timing accuracy and sensitivity based on the second pulse synchronization deviation and BeiDou signal power of the device under test under benchmark operating conditions. The anti-interference capability evaluation module is used to obtain degradation performance evaluation results based on the second pulse synchronization deviation and satellite communication characteristics of the device under test under suppression interference conditions. The anti-spoofing capability evaluation module is used to calculate timing deviation and spoofing attack probability based on the multimodal timing characteristics of the device under test under mixed suppression and spoofing interference conditions to evaluate the spoofing protection capability of the device under test and obtain spoofing protection evaluation results. The comprehensive capability evaluation module is used to integrate the benchmark performance evaluation results, degradation performance evaluation results and spoofing protection evaluation results to obtain the final test results.

[0014] The beneficial effects of this application are: 1. By employing a hierarchical detection logic encompassing baseline operating conditions, suppression interference conditions, and mixed interference conditions, the previously isolated precision testing, sensitivity testing, and anti-interference testing are linked into a cohesive whole. This transforms the final detection result from a snapshot of a single point into a dynamic portrait of the equipment's performance throughout its entire lifecycle. Furthermore, by establishing a quantitative relationship between second pulse synchronization deviation and BeiDou signal power under baseline operating conditions, introducing satellite communication characteristics under suppression interference conditions, and utilizing multimodal timing characteristics to calculate timing deviation and spoofing attack probability under mixed interference conditions, a quantitative mapping between interference power and the degree of timing performance degradation is achieved. This provides reproducible and quantifiable objective criteria for judging the detection results, significantly improving the reliability and timeliness of comprehensive performance testing of BeiDou timing modules in power scenarios. 2. The timing deviation is calculated by using an LSTM network with AGC voltage timing and channel carrier-to-noise ratio as inputs, and the CNN network is calculated with time-frequency domain features, pseudorange, and carrier phase as inputs to calculate the probability of spoofing attacks. This fully utilizes the complementary information between multimodal timing features, and the weighted fusion of the two improves the accuracy and robustness of spoofing attack identification. The two-level verification mechanism, which combines preliminary judgment and comprehensive evaluation, not only ensures detection efficiency, but also further improves the reliability of anti-spoofing capability assessment through multimodal timing features. Attached Figure Description

[0015] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. The drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0016] Figure 1 This is a flowchart of a BeiDou timing anti-interference detection method for power grid edge devices according to an embodiment of this application; Figure 2 This is a schematic diagram of an interference power and timing deviation mapping curve according to an embodiment of this application. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description of this application is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely one preferred embodiment of this application and are only used to explain this application. They do not limit the scope of protection of this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0018] Example 1: As Figure 1 As shown, a method for detecting interference from BeiDou timing on power grid edge devices includes steps S1-S4, wherein: S1. Based on the second pulse synchronization deviation and BeiDou signal power of the device under test under the reference working conditions, obtain the reference performance evaluation results of the protection timing accuracy and sensitivity.

[0019] In an optional embodiment, step S1 includes: S11. Perform radio frequency signal power calibration on the testing equipment and establish a power comparison table between Beidou test signals and interference signals; S12. The output power of the detection equipment is calibrated based on the power comparison table in order to establish the benchmark operating conditions of the fusion physical field under electromagnetic shielding environment. S13. Perform basic testing on the timing accuracy and sensitivity of the device under test according to the benchmark operating conditions, and collect the second pulse synchronization deviation and Beidou signal power during the testing process. S14. Obtain the timing accuracy assessment result based on the second pulse synchronization deviation; S15. Based on the timing accuracy assessment results and the BeiDou signal power, obtain the assessment results of acquisition sensitivity and tracking sensitivity; The timing accuracy evaluation results, acquisition sensitivity evaluation results, and tracking sensitivity evaluation results form the benchmark performance evaluation results.

[0020] In this embodiment, the device under test (DUT) is a power grid edge device, specifically referring to the timing and positioning module under test in the power system. The testing equipment is configured as an integrated system for testing the timing performance of the DUT. It includes an anechoic chamber, a BeiDou signal simulation unit, an interference signal injection unit, a time-frequency reference measurement unit, and a data acquisition and judgment unit. The anechoic chamber provides an electromagnetically shielded testing environment to isolate external electromagnetic interference. The BeiDou signal simulation unit radiates simulated standard BeiDou navigation signals into the DUT within the anechoic chamber. The interference signal injection unit adjusts the radio frequency signal band and power to generate interference signals. The time-frequency reference measurement unit uses existing BeiDou equipment in the power system as a reference to accurately calculate the timing error of the DUT and obtain the second pulse synchronization deviation. The data acquisition and judgment unit collects second pulse data, satellite communication characteristics, and timing data during the interference detection process, determines whether the DUT is qualified according to standard requirements, and outputs a qualified / unqualified conclusion.

[0021] Specifically, before the test begins, the power meter sequentially outputs the frequency signal and the interference signal used to establish the interference condition at the standard test position. The measured value of the power meter corresponding to each set power is recorded, and a power comparison table between the test signal and the interference signal is established. This allows the output power of all subsequent BeiDou signals and interference signals to be corrected in real time based on this comparison table, ensuring the feasibility and authenticity of the interference test condition.

[0022] In this embodiment, the power output error of the detection equipment itself is eliminated through power calibration and calibration steps, ensuring the reproducibility of the reference operating condition in the anechoic chamber environment. At the same time, the timing accuracy and acquisition and tracking sensitivity are tested in an integrated manner under the same reference operating condition, which not only conforms to the actual working logic of the grid edge equipment, but also avoids the problem of inconsistent operating conditions caused by separate tests, providing an accurate and reliable benchmark for performance degradation comparison under subsequent interference conditions.

[0023] Specifically, step S14 includes: The second pulse data output by the device under test under reference operating conditions is collected, and the second pulse synchronization deviation is obtained based on the time difference sequence between the second pulse data and the reference second pulse. Calculate the statistical characteristics of the second pulse synchronization deviation. If the statistical characteristics are less than or equal to the deviation threshold and the statistical characteristics are not greater than the time jump threshold, then it is determined that the timing accuracy of the device under test meets the standard requirements under the reference operating conditions, and the timing accuracy evaluation result is obtained.

[0024] In some embodiments, the statistical characteristics of the second pulse synchronization deviation include the mean, standard deviation, or peak-to-peak value. The peak-to-peak value represents the distribution of the second pulse error, and is obtained here based on the arithmetic square root of the variance of the second pulse error. By benchmarking against industry standard values, if the statistical characteristics are less than or equal to the deviation threshold and no absolute value exceeds the time jump threshold (e.g., a jump greater than 3 microseconds), the timing accuracy of the device under test is determined to meet the standard. The industry standard refers to the power industry standard Q / GDW12229-2022, which specifies the tolerance requirements for continuous interference, pulse interference, and frequency sweep interference.

[0025] In this embodiment, by comparing the statistical characteristics of the second pulse synchronization deviation with the deviation threshold and the time jump threshold, it is determined whether the timing accuracy of the device under test meets the standard requirements. This assesses both steady-state accuracy and detects dynamic jump risks, overcoming the problem of traditional methods that only focus on average deviation and ignore sudden interference. The quantitative determination using dual thresholds makes the timing accuracy assessment results more robust and engineering-practical, accurately reflecting the time synchronization stability of grid edge devices in real-world complex electromagnetic environments.

[0026] Specifically, step S15 includes: By gradually reducing the radio frequency signal power of the testing equipment to adjust the baseline operating condition, it is determined whether the device under test can re-acquire the satellite signal and complete the first positioning after losing lock. If so, it is determined that the acquisition sensitivity of the device under test under the baseline operating condition meets the standard requirements, and the acquisition sensitivity evaluation result is obtained. Based on the acquisition sensitivity evaluation results, the power of the reference operating condition is dynamically adjusted to detect the tracking sensitivity of the device under test and obtain the tracking sensitivity evaluation results.

[0027] In some embodiments, during sensitivity testing, starting from normal power, the output power of the BeiDou simulator integrated in the BeiDou signal simulation unit is gradually reduced with an adaptive step size, maintaining each step for a certain period of time, such as 20 seconds. A binary search or golden section search algorithm is used to automatically approximate the time from loss of lock to initial repositioning of the device under test. If the process of losing lock and repositioning can be achieved, the sensitivity of the device under test is determined to meet the standard. The sensitivity assessment result includes a sensitivity value and a judgment result; the sensitivity value is the minimum power required to achieve initial repositioning from loss of lock.

[0028] It should be noted that for the BeiDou signal receiver inside the device under test, the carrier power of the satellite signal must reach or exceed a certain minimum threshold for the receiver to successfully acquire, track, demodulate the navigation message, and calculate the position. This minimum threshold is called the acquisition sensitivity.

[0029] Furthermore, the acquisition sensitivity is a critical value. When the simulated BeiDou signal power is higher than this value, the device under test (DUT) can achieve positioning and timing; when it is lower, positioning and timing are not possible. Because the BeiDou signal receiver inside the DUT has noise and randomness, the boundary found directly by a fixed step size may not be accurate enough. For example, it may be able to position at -132dBm but not at -133dBm, but the actual acquisition sensitivity may be -132.3dBm. Therefore, this embodiment uses an adaptive algorithm to find this critical point, rather than simply adjusting the power level and trying each level. For example, it first finds the positioning and positioning interval with a larger step size, and then adjusts back and forth within the interval with smaller step sizes until the power difference obtained from multiple consecutive searches is less than the standard threshold, and the positioning status is stable.

[0030] In this embodiment, the recovery process of the power grid edge device after a signal interruption is simulated by the actual test method of re-acquisition after loss of lock. Its acquisition sensitivity value directly corresponds to the minimum power threshold for the device to re-establish time synchronization, ensuring that the starting conditions of the tracking sensitivity test match the actual acquisition capability, avoiding invalid tests caused by blindly reducing power, and improving detection efficiency and result accuracy.

[0031] Specifically, the step of dynamically adjusting the power of the reference operating condition based on the acquisition sensitivity evaluation result to perform tracking sensitivity detection of the device under test and obtain the tracking sensitivity evaluation result includes: The minimum power required for the device under test to complete its initial positioning is used as the acquisition sensitivity value, and it is added to the preset power to obtain the reference power for adjusting the radio frequency signal power; The testing equipment uses the reference power as the starting power of the reference operating condition and gradually reduces the radio frequency signal power to adjust the reference operating condition; Based on the baseline operating conditions after power adjustment, monitor whether the device under test can maintain positioning and timekeeping within a continuous time period. If so, the tracking sensitivity of the device under test under the reference operating conditions is determined to meet the standard requirements, and the minimum power required for the device under test to maintain positioning and timekeeping is taken as the tracking sensitivity value, thus obtaining the tracking sensitivity evaluation result including the tracking sensitivity value.

[0032] In this embodiment, tracking sensitivity is the minimum power required for the device under test to maintain continuous positioning after it has already been positioned, such as the minimum power required to maintain a lock for 60 seconds without losing it. Tracking sensitivity does not require reacquisition; it only needs to maintain the tracking loop lock and continuously demodulate the navigation message. Therefore, tracking sensitivity is typically lower than acquisition sensitivity.

[0033] Specifically, based on the acquisition sensitivity, the step size is increased, and then the BeiDou signal analog power is continuously reduced with an adaptive step size. The device under test (DUT) is monitored to see if it can maintain positioning and timing over a continuous time period. If it can maintain positioning and timing over a continuous time period, it indicates that the DUT possesses tracking sensitivity, and the minimum maintenance power is taken as the tracking sensitivity value. This detection process is repeated at least three times, and the average of the tracking sensitivity values ​​is taken as the final tracking sensitivity value. This value, combined with the judgment result of whether the device possesses tracking sensitivity, is used as the final tracking sensitivity evaluation result.

[0034] In this embodiment, by adding the capture sensitivity value and the preset power as the starting condition for the reference power, the tracking sensitivity test is ensured to begin when the device has stabilized its tracking. Then, by evaluating the timekeeping capability over a continuous time period, the device's ability to maintain continuous timekeeping under signal weakening conditions is truly reflected.

[0035] S2. Based on the second pulse synchronization deviation and satellite communication characteristics of the device under test under suppression interference conditions, obtain the degradation performance evaluation results.

[0036] Specifically, satellite communication characteristics are obtained by reading and parsing the standard navigation data statements output by the device under test (DUT) using a detection device. These characteristics include at least the number of visible satellites, pseudorange, channel carrier-to-noise ratio (CNR) of the satellite tracking channel, and carrier phase. The satellite tracking channel is the processing channel for each satellite signal within the DUT's BeiDou signal receiver; one channel tracks one satellite. The CNR can be used to analyze the selective impact of interference on satellites in different directions, determining whether the receiver's anti-interference capability is uniform.

[0037] In an optional embodiment, step S2 includes: S21. Based on the suppression interference conditions of different interference types, perform out-of-band and in-band anti-interference tests on the equipment under test respectively. The interference types include continuous wave, pulse interference, frequency sweep interference, modulation interference and multi-tone interference. S22. When performing out-of-band anti-interference test, the second pulse synchronization deviation of the device under test and the satellite communication characteristics including channel carrier-to-noise ratio and satellite visibility are obtained during the test. If the second pulse synchronization deviation and the satellite communication characteristics both meet the corresponding out-of-band anti-interference judgment rules, the out-of-band anti-interference of the device under test is judged to be qualified. S23. When performing in-band anti-interference test, acquire the second pulse data of the device under test during the test, and determine whether the in-band anti-interference of the device under test is qualified by combining the timing mode of the device under test. S24. The out-of-band and in-band anti-interference test results of the device under test shall be used as the degradation performance evaluation results.

[0038] In some possible implementations, under continuous wave interference, the BeiDou analog signal is a single-frequency sine wave with power concentrated in an extremely narrow bandwidth, forming a spike in the spectrum. This causes compression of the AGC circuit at the front end of the BeiDou signal receiver, i.e., voltage compression of the RF front-end automatic gain control (AGC) circuit of the time and positioning module under test in the power system. The overall channel carrier-to-noise ratio (CNR) decreases, and in severe cases, the receiving channel is blocked. The anti-interference capability of the device under test (DUT) is determined by monitoring changes in AGC voltage and channel CNR. Under pulse interference, the BeiDou analog signal is a periodic short pulse. The anti-interference capability of the DUT is determined by monitoring whether there are instantaneous jumps in the second pulse, whether the loop can recover between pulses, and the average time of loss of lock. Under frequency sweep interference, the center frequency changes rapidly within a certain range. The anti-interference capability of the device is determined by monitoring whether there are periodic fluctuations in the second pulse synchronization deviation and changes in the channel CNR. Under modulation interference, the carrier amplitude or frequency changes regularly, generating sideband components and causing Doppler tracking errors. The anti-interference capability of the device is determined by the second pulse jitter amplitude and pseudorange noise changes. In multi-tone interference scenarios, multiple notches can form within the bandwidth of a BeiDou signal receiver, potentially blocking multiple satellite channels simultaneously and causing some satellites to lose lock. Therefore, the anti-interference capability of the equipment is assessed by observing changes in the number of visible satellites and the channel carrier-to-noise ratio. The difference between various interference types lies in the different signal waveform configurations output by the interference signal injection unit in the detection equipment.

[0039] Specifically, when performing out-of-band anti-interference testing, the testing equipment injects a continuous wave interference signal in the corresponding frequency band and increases the interference power in fixed power increments. Each power level lasts for a period of time, and the second pulse synchronization deviation and satellite communication characteristics of the device under test are collected simultaneously. When the interference power reaches the preset value, if the device under test can maintain time synchronization with the BeiDou satellite clock and the change in the second pulse data per second does not exceed the preset pulse, that is, the second pulse synchronization deviation is less than the deviation threshold, the visible satellite number remains greater than the set value, and the channel carrier-to-noise ratio remains stable, and the above three indicators are met simultaneously, then the out-of-band anti-interference of the device under test is judged to be qualified.

[0040] In some examples, during out-of-band interference testing, the interference power starts from 0 and increases in 5dB increments, with each power level maintained for 2 minutes. The second pulse data of the device under test is collected. When the out-of-band interference power reaches 15dB, if the adjustment of the second pulse data per second is less than the standard setting value, and the device under test maintains time synchronization, the carrier-to-noise ratio of all channels remains stable, or although it decreases, it remains within a healthy range that the device can effectively track, and the number of visible satellites always remains greater than or equal to the preset value, then the out-of-band anti-interference is qualified.

[0041] In this embodiment, various electromagnetic interference scenarios that power grid edge devices may encounter are comprehensively simulated through multi-type, dual-band suppression interference tests. In out-of-band testing, channel carrier-to-noise ratio and satellite visibility are introduced as auxiliary judgment features, which can distinguish the impact of signal quality degradation caused by interference and changes in satellite geometric distribution, thereby improving the accuracy of judgment. In in-band testing, a comprehensive judgment is made in combination with the timing mode, which is more in line with the actual working state of the equipment, thereby improving the comprehensiveness and reliability of the anti-interference capability assessment.

[0042] Specifically, step S23 includes: The detection equipment increases the interference power in steps according to a preset value, and simultaneously collects the second pulse data of the device under test during the change of interference power; When the interference power is within the range of the low noise power, if the change per second of the second pulse data does not exceed the preset value, the device under test is deemed to be qualified for in-band interference immunity; or, if the device under test switches to a timekeeping state that maintains time synchronization through an internal clock, and the timekeeping error is lower than the industry standard error, the device under test is deemed to be qualified for in-band interference immunity.

[0043] In this embodiment, by progressively increasing the interference power, the degradation curve of device performance as the interference intensity changes can be accurately obtained, quantifying the mapping relationship between interference power and timing accuracy. At the same time, two independent qualification judgment paths are provided: directly maintaining the stability of the second pulse and switching to the timekeeping state with the timekeeping error meeting the standard. These correspond to the device's ability to maintain normal timekeeping under interference and its ability to safely degrade when the interference is too strong, respectively. This fully considers the different response modes of grid edge devices in actual interference environments, avoids missed judgments or misjudgments caused by a single judgment rule, and enhances the engineering adaptability of the detection results.

[0044] In some examples, the interference power starts from the noise floor power of the active antenna of the device under test and increases in 5dB steps. When the in-band interference power reaches the noise floor power range, for example, the noise floor power is P, and its range is [P, P+40dB], if the device under test can still maintain time synchronization, then the in-band interference immunity is qualified.

[0045] Furthermore, in-band interference directly affects the satellite signal frequency band, making the judgment logic more complex. Therefore, it is necessary to combine the timing mode for dynamic judgment. If the device under test maintains satellite timing synchronization, then under P+40dB interference, if the change per second of the second pulse does not exceed the preset value, the device can be judged to have in-band interference immunity. If the device under test switches to relying on its internal clock for time synchronization, it indicates that the device has entered a timekeeping state. If the device's timing accuracy meets the relevant requirements of the power industry standards, then the device is judged to have in-band interference immunity.

[0046] In some embodiments, after determining that the device has in-band anti-interference capability, interference detection function verification is performed. By adjusting the interference power, when the interference power reaches P+20dB, it is checked whether the serial port of the device under test outputs an interference detection flag that meets the expectations, thereby evaluating whether the device under test has interference sensing and alarm capabilities.

[0047] It is understandable that the differences between out-of-band and in-band interference are: different spectral positions, with out-of-band interference testing the roll-off characteristics of the filter, while in-band interference directly enters the signal channel; different interference power requirements, with out-of-band interference allowing up to 15dBm, while in-band interference only needs to reach P+40dB, which is much weaker than out-of-band interference, making in-band interference more sensitive; and different failure modes, with excessive out-of-band interference potentially causing front-end saturation and AGC malfunction, while excessive in-band interference directly suppresses the signal, causing relevant peaks to be overwhelmed. The mechanism for diagnosing interference failure is as follows: when the second pulse deviation begins to increase or even loses lock, by observing the decreasing trend of the number of visible satellites and the attenuation of the carrier-to-noise ratio, it can be determined whether the interference causes loss of lock by reducing the signal-to-noise ratio or by causing front-end blocking through saturation or nonlinearity, such as a sudden drop in the number of satellites to zero or an abnormal jump in the carrier-to-noise ratio.

[0048] In some embodiments, such as Figure 2 As shown, an interference-time synchronization deviation mapping curve is plotted with interference power as the horizontal axis and second pulse synchronization deviation as the vertical axis. The second pulse synchronization deviation in the figure is represented as 1PPS time synchronization deviation. The critical threshold for Class I modules in the figure refers to the time synchronization deviation threshold for Class I BeiDou modules specified in industry standard Q / GDW12229-2022. The curve directly locates the interference power value corresponding to when the second pulse synchronization deviation exactly reaches 1000ns, i.e., the -15dBm critical interference power marked in the figure. Therefore, based on the measured critical interference power and the tolerance power specified in the standard, the critical threshold for anti-interference can be accurately calibrated, and the anti-interference margin of the device under test can be located, providing a quantitative basis for standard compliance judgment. Simultaneously, the curve divides the interference process into three stages: normal time synchronization zone, accuracy degradation zone, and loss of synchronization zone, completely reconstructing the entire process from stable operation to accuracy decay and eventual failure of the equipment. This allows for intuitive judgment of whether the equipment state has reached a steady state under each interference power level and direct verification of the reproducibility of test results, thus meeting the core requirements of controllable conditions and reproducible results in power type testing.

[0049] S3. Based on the multimodal timing characteristics of the device under test under mixed suppression and deception interference conditions, calculate the timing deviation and deception attack probability to evaluate the deception protection capability of the device under test and obtain the deception protection assessment results.

[0050] In an optional embodiment, step S3 includes: S31. Based on the carrier phase of the BeiDou satellite signal simulated by the detection equipment, generate a zero-adjustment deception signal after phase reversal; S32. Inject a zero-adjustment deception signal under the suppression jamming condition to construct a deception-based hybrid jamming condition; S33. Collect the second pulse synchronization deviation and deception attack field of the device under test under the deceptive mixed interference condition. If the device under test collects the deception attack field marked with a deception event and issues an alarm, and the time when the deception event mark appears is less than the time when the second pulse synchronization deviation first exceeds the threshold, it is preliminarily determined that the device under test has anti-deception capability. S34. Simultaneously, collect the multimodal timing characteristics of the device under test under deceptive mixed interference conditions, and use a neural network algorithm to calculate the timing deviation and deceptive attack probability to comprehensively evaluate the anti-deception capability of the device under test and obtain the final deceptive protection evaluation result.

[0051] Specifically, the zero-adjustment spoofing signal is 180 degrees out of phase with the real BeiDou signal carrier, and the power of the spoofing signal is lower than that of the real BeiDou signal. The spoofing attack field is a preset spoofing alarm field used to identify the occurrence of spoofing events. When the field value is detected as 1, it indicates that a spoofing attack exists. If the device under test issues an alarm when it collects the field marked with a spoofing event, and the time point of collecting the spoofing alarm field is earlier than the time point when the second pulse synchronization deviation first exceeds the limit, it indicates that the device under test has anti-spoofing capability.

[0052] However, simply detecting a spoofing event marker is insufficient to prove that the device under test (DUT) possesses adequate anti-spoofing capabilities. Furthermore, the device's timing accuracy must not be significantly compromised before an alarm is issued; that is, the second pulse synchronization deviation must not exceed the limit. Therefore, a comprehensive judgment needs to be made by combining the spoofing event detection time with the time when the second pulse synchronization deviation first exceeds the limit.

[0053] Furthermore, by comparing the detection time of the deception event marker with the detection time of the second pulse synchronization deviation exceeding the limit, the detection response speed of the device under test (DUT) can be determined, but it cannot be used as a direct basis for final compliance with standard requirements. To avoid the DUT misinterpreting normal signals as deception during the injection of deception signals, and to prevent the second pulse from changing before the DUT issues an alarm, thus causing the alarm to fail, this embodiment uses a neural network algorithm to calculate the timing deviation and the probability of a deception attack to comprehensively evaluate the DUT's anti-spoofing capability, ensuring the reliability and accuracy of the anti-spoofing capability detection results.

[0054] Specifically, in step S34, a neural network algorithm is used to calculate the timing deviation and the probability of spoofing attacks to comprehensively evaluate the anti-spoofing capability of the device under test and obtain the final spoofing protection evaluation result, including: The multimodal timing features include AGC voltage sequence, time-frequency domain features, channel carrier-to-noise ratio, pseudorange, and carrier phase; The timing deviation is obtained by using the AGC voltage timing and channel carrier-to-noise ratio as input parameters based on the LSTM network. Based on a CNN network, the probability of spoofing attacks is obtained by using time-frequency domain features, pseudorange, and carrier phase as input parameters. The interference confidence level is obtained by weighted summation of the time sequence deviation and the spoofing attack probability. If the time when the interference confidence level first exceeds the confidence level threshold is greater than the time when the spoofing event marker appears, the device under test is determined to have qualified anti-spoofing capability.

[0055] In some embodiments, the AGC voltage sequence is acquired by: acquiring it at a set sampling rate after analog-to-digital conversion via the AGC control pin of the RF front-end chip of the device under test; or by reading the AGC gain control word (i.e., the gain control digital quantity) stored in the internal register of the RF front-end chip and converting it into an equivalent voltage value through linear mapping. The AGC voltage sequence directly reflects the real-time response of the RF front-end to the received signal strength. Under suppression interference, it exhibits a rapid gain increase, while under deceptive interference, it shows an abnormally stable or oscillating mode, which is an important characteristic for distinguishing between the two types of interference.

[0056] In some embodiments, the time-frequency domain features include a power spectral density feature vector, a band energy ratio, and a band energy concentration. The extraction steps include: performing a short-time Fourier transform on the intermediate frequency (IF) signal to extract the power spectral density value, and then forming a power spectral density feature vector through logarithmic compression; performing wavelet packet decomposition on the IF signal, and extracting the energy value and logarithmic energy entropy for each decomposed band; extracting the energy ratio of adjacent bands based on the energy value, and extracting the band energy concentration based on the logarithmic energy entropy. By acquiring the time-frequency domain features, the spectral distortion mode of the BeiDou signal under interference can be comprehensively characterized.

[0057] In some embodiments, the LSTM (Long Short-Term Memory) network adopts a two-layer architecture. The first layer is used to process the input features fused from the AGC voltage sequence and the channel carrier-to-noise ratio to initially extract the temporal dependency between the two. The second layer takes the output of the first layer as the input parameter to further extract the temporal dependency between the AGC voltage sequence and the channel carrier-to-noise ratio. The hidden state vector output from the second layer is input into the fully connected layer for local feature integration and positive value filtering by the ReLU activation function, and then mapped to the temporal deviation score through the output layer.

[0058] In some embodiments, the CNN (Convolutional Neural Network) employs a three-layer one-dimensional convolutional structure. The input parameters are a feature vector obtained by concatenating a time-frequency domain feature vector, a pseudorange difference sequence, and a carrier phase difference sequence. The first convolutional kernel covers the low-frequency information of the time-frequency domain feature vector, the second layer covers the mid-frequency information, and the third layer covers the high-frequency information. The time-frequency domain feature vector is formed by combining the power spectrum feature vector, the band energy ratio, and the band energy concentration. By extracting the pseudorange difference and carrier phase difference from the satellite channel with the highest carrier-to-noise ratio in the current tracking loop, pseudorange difference sequences and carrier phase difference sequences are obtained, respectively.

[0059] It should be noted that the algorithm parameters of the LSTM network and CNN network in this implementation are not limited to specific values. Instead, the goal is to maintain an optimal balance between feature extraction effectiveness and computational complexity during the detection process. The specific parameters can be flexibly configured according to the actual situation.

[0060] Furthermore, the weights of temporal deviation and deception attack probability are dynamically adjusted using a scenario confidence-based dynamic weight adjustment mechanism. When the attack mode changes abruptly, the weight of the deception attack probability is increased, and when the attack mode becomes progressive, the weight of temporal deviation is increased. This enables adaptive detection for different attack scenarios and avoids the problem of insufficient adaptability in scenarios dominated by a single attack mode.

[0061] In this embodiment, considering that the power system faces hybrid interference attacks with progressive trolling attacks and abrupt signal replacement patterns, under progressive trolling attacks, the AGC voltage changes slowly and the channel carrier-to-noise ratio gradually decreases, exhibiting a progressive time-series evolution characteristic; under abrupt signal replacement, the AGC voltage changes abruptly and instantaneous spectral jumps occur in the time-frequency domain. Addressing the physical differences between the two, LSTM is used to capture the time-dependent AGC voltage and channel carrier-to-noise ratio, utilizing its gated memory mechanism to capture the slow evolution pattern of progressive trolling attacks; CNN is used to capture instantaneous anomalies in the time-frequency domain features, pseudorange difference, and carrier phase difference. Through this precise matching of features with the attack model, the impact of different attack patterns on the device under test can be accurately identified, and detection biases caused by differences in RF front-end gain and antenna characteristics of different devices can be eliminated, improving the detection accuracy and effectiveness under hybrid interference modes.

[0062] Meanwhile, by comparing the order of the time when the interference confidence exceeds the threshold and the time when the deception event marker appears, it is possible to verify whether the anti-spoofing algorithm inside the device responds before the actual physical anomaly occurs. This provides a quantitative assessment basis for the real-time performance and effectiveness of the device's anti-spoofing capability, further enhancing the objectivity of the detection results.

[0063] S4. Integrate the benchmark performance evaluation results, degradation performance evaluation results, and deception protection evaluation results to obtain the final test results.

[0064] Specifically, the baseline performance evaluation results, degradation performance evaluation results, and deception protection evaluation results are integrated, including timing accuracy statistical characteristics, acquisition sensitivity values, tracking sensitivity values ​​and corresponding evaluation results, interference detection function judgment and minimum detection power, interference power under out-of-band and in-band anti-interference conditions, second pulse synchronization deviation, number of visible satellites and channel carrier-to-noise ratio. The above detection information is integrated to generate a structured detection report.

[0065] Example 2, based on the same inventive concept, also provides a BeiDou timing anti-interference detection system for power grid edge devices, corresponding to a BeiDou timing anti-interference detection method for power grid edge devices, comprising: The benchmark performance evaluation module is used to obtain the benchmark performance evaluation results of protection timing accuracy and sensitivity based on the second pulse synchronization deviation and Beidou signal power of the device under test under benchmark operating conditions. The anti-interference capability assessment module is used to obtain the degradation performance assessment results based on the second pulse synchronization deviation and satellite communication characteristics of the device under test under suppression interference conditions. The anti-spoofing capability assessment module is used to calculate the timing deviation and spoofing attack probability based on the multimodal timing characteristics of the device under test under mixed suppression and spoofing interference conditions, so as to assess the spoofing protection capability of the device under test and obtain the spoofing protection assessment results. The comprehensive capability assessment module is used to integrate the benchmark performance assessment results, degradation performance assessment results, and deception protection assessment results to obtain the final test results.

[0066] In this embodiment, by employing a hierarchical detection logic encompassing baseline operating conditions, suppression interference operating conditions, and mixed interference operating conditions, the previously isolated accuracy tests, sensitivity tests, and anti-interference tests are linked into an organic whole. This transforms the final detection result from a single-point snapshot into a dynamic portrait of the equipment's performance throughout its entire lifecycle. Simultaneously, by establishing a quantitative relationship between second pulse synchronization deviation and BeiDou signal power under baseline operating conditions, introducing satellite communication characteristics under suppression interference operating conditions, and utilizing multimodal timing characteristics to calculate timing deviation and spoofing attack probability under mixed interference operating conditions, a quantitative mapping between interference power and the degree of timing performance degradation is achieved. This provides reproducible and quantifiable objective judgment criteria for the detection results, thereby significantly improving the reliability and effectiveness of comprehensive performance testing of the BeiDou timing module in power scenarios.

[0067] The above-described embodiments are preferred embodiments of this application and are not intended to limit the specific scope of this application. The scope of this application includes but is not limited to the specific embodiments described above. All equivalent changes made in accordance with the shape, structure, and method of this application are within the protection scope of this application.

Claims

1. A method for detecting interference from BeiDou timing on power grid edge devices, characterized in that: Includes the following steps: Based on the second pulse synchronization deviation and BeiDou signal power of the device under test (DUT) under reference operating conditions, a benchmark performance evaluation result for protection timing accuracy and sensitivity is obtained. Specifically, the radio frequency signal power of the DUT is calibrated, and a power comparison table between the BeiDou test signal and interference signals is established. The output power of the DUT is calibrated based on the power comparison table to establish a benchmark operating condition for the fusion physical field under electromagnetic shielding. Basic testing of timing accuracy and sensitivity is performed on the DUT under the benchmark operating conditions, and the second pulse synchronization deviation and BeiDou signal power collected during the testing process are acquired. A timing accuracy evaluation result is obtained based on the second pulse synchronization deviation. Based on the timing accuracy evaluation result and the BeiDou signal power, evaluation results for acquisition sensitivity and tracking sensitivity are obtained. The timing accuracy evaluation result, acquisition sensitivity evaluation result, and tracking sensitivity evaluation result constitute the benchmark performance evaluation result. Based on the second pulse synchronization deviation and satellite communication characteristics of the device under test (DUT) under suppression interference conditions, a degradation performance evaluation result is obtained. Specifically, out-of-band and in-band immunity tests are performed on the DUT under suppression interference conditions for different interference types, including continuous wave, pulse interference, frequency sweep interference, modulation interference, and multi-tone interference. During the out-of-band immunity test, the second pulse synchronization deviation and satellite communication characteristics (including channel carrier-to-noise ratio and satellite visibility) of the DUT are acquired. If both the second pulse synchronization deviation and the satellite communication characteristics meet the corresponding out-of-band immunity judgment rules, the DUT is deemed to have passed the out-of-band immunity test. During the in-band immunity test, the second pulse data of the DUT is acquired, and its in-band immunity is determined based on the DUT's timing mode. The out-of-band and in-band immunity test results of the DUT are used as the degradation performance evaluation result. Based on the multimodal timing characteristics of the device under test (DUT) under mixed suppression and deception interference conditions, the timing deviation and deception attack probability are calculated to assess the DUT's deception protection capability and obtain the deception protection assessment result. Specifically, a phase-reversed nulling deception signal is generated based on the carrier phase of the BeiDou satellite signal simulated by the detection device. This nulling deception signal is injected under suppression interference conditions to construct a mixed deception interference condition. The second pulse synchronization deviation and deception attack field of the DUT under the mixed deception interference condition are collected. If the DUT collects a deception attack field marked with a deception event and issues an alarm, and the time of the deception event mark is less than the time when the second pulse synchronization deviation first exceeds the threshold, the DUT is preliminarily determined to have anti-deception capability. Simultaneously, the multimodal timing characteristics of the DUT under the mixed deception interference condition are collected, and a neural network algorithm is used to calculate the timing deviation and deception attack probability to comprehensively assess the DUT's anti-deception capability and obtain the final deception protection assessment result. The final test results are obtained by integrating the benchmark performance evaluation results, the degradation performance evaluation results, and the deception protection evaluation results.

2. The method for detecting interference from BeiDou timing on grid edge devices according to claim 1, characterized in that: The process of obtaining the timing accuracy assessment result based on the second pulse synchronization deviation includes: The second pulse data output by the device under test under reference operating conditions is collected, and the second pulse synchronization deviation is obtained based on the time difference sequence between the second pulse data and the reference second pulse. Calculate the statistical characteristics of the second pulse synchronization deviation. If the statistical characteristics are less than or equal to the deviation threshold and the statistical characteristics are not greater than the time jump threshold, then it is determined that the timing accuracy of the device under test meets the standard requirements under the reference operating conditions, and the timing accuracy evaluation result is obtained.

3. The method for detecting interference from BeiDou timing in power grid edge devices according to claim 1, characterized in that: The process of obtaining the assessment results of acquisition sensitivity and tracking sensitivity based on the timing accuracy assessment results and the BeiDou signal power includes: By gradually reducing the radio frequency signal power of the testing equipment to adjust the baseline operating condition, it is determined whether the device under test can re-acquire the satellite signal and complete the first positioning after losing lock. If so, it is determined that the acquisition sensitivity of the device under test under the baseline operating condition meets the standard requirements, and the acquisition sensitivity evaluation result is obtained. Based on the acquisition sensitivity evaluation results, the power of the reference operating condition is dynamically adjusted to detect the tracking sensitivity of the device under test and obtain the tracking sensitivity evaluation results.

4. The method for detecting interference from BeiDou timing on power grid edge devices according to claim 3, characterized in that: The step of dynamically adjusting the power of the baseline operating condition based on the capture sensitivity evaluation result to detect the tracking sensitivity of the device under test and obtain the tracking sensitivity evaluation result includes: The minimum power required for the device under test to complete its initial positioning is used as the acquisition sensitivity value, and it is added to the preset power to obtain the reference power for adjusting the radio frequency signal power; The testing equipment uses the reference power as the starting power of the reference operating condition and gradually reduces the radio frequency signal power to adjust the reference operating condition; Based on the baseline operating conditions after power adjustment, monitor whether the device under test can maintain positioning and timekeeping within a continuous time period. If so, the tracking sensitivity of the device under test under the reference operating conditions is determined to meet the standard requirements, and the minimum power required for the device under test to maintain positioning and timekeeping is taken as the tracking sensitivity value, thus obtaining the tracking sensitivity evaluation result including the tracking sensitivity value.

5. The method for detecting interference from BeiDou timing on grid edge devices according to claim 1, characterized in that: The process of acquiring the second pulse data of the device under test (DUT) during the test, and determining whether the DUT's in-band anti-interference capability is qualified based on the DUT's timing mode, includes: The detection equipment increases the interference power in steps according to a preset value, and simultaneously collects the second pulse data of the device under test during the change of interference power; When the interference power is within the low noise power range, if the change per second of the second pulse data does not exceed a preset value, the device under test is deemed to have qualified in-band interference immunity; or, If the device under test switches to a timekeeping state that maintains time synchronization through an internal clock, and the timekeeping error is lower than the industry standard error, the device under test is deemed to have passed the in-band interference immunity test.

6. The method for detecting interference from BeiDou timing on power grid edge devices according to claim 1, characterized in that: The method employs a neural network algorithm to calculate timing deviation and spoofing attack probability to comprehensively evaluate the anti-spoofing capability of the device under test and obtain the final spoofing protection evaluation result, including: The multimodal timing features include AGC voltage sequence, time-frequency domain features, channel carrier-to-noise ratio, pseudorange, and carrier phase; The timing deviation is obtained by using the AGC voltage timing and channel carrier-to-noise ratio as input parameters based on the LSTM network. Based on a CNN network, the probability of spoofing attacks is obtained by using time-frequency domain features, pseudorange, and carrier phase as input parameters. The interference confidence level is obtained by weighted summation of the time sequence deviation and the spoofing attack probability. If the time when the interference confidence level first exceeds the confidence level threshold is greater than the time when the spoofing event marker appears, the device under test is determined to have qualified anti-spoofing capability.

7. A BeiDou timing anti-interference detection system for power grid edge equipment, characterized in that: An anti-interference detection method for BeiDou timing of power grid edge devices as described in any one of claims 1-6, comprising: The benchmark performance evaluation module is used to obtain the benchmark performance evaluation results of protection timing accuracy and sensitivity based on the second pulse synchronization deviation and Beidou signal power of the device under test under benchmark operating conditions. The anti-interference capability assessment module is used to obtain the degradation performance assessment results based on the second pulse synchronization deviation and satellite communication characteristics of the device under test under suppression interference conditions. The anti-spoofing capability assessment module is used to calculate the timing deviation and spoofing attack probability based on the multimodal timing characteristics of the device under test under mixed suppression and spoofing interference conditions, so as to assess the spoofing protection capability of the device under test and obtain the spoofing protection assessment results. The comprehensive capability assessment module is used to integrate the benchmark performance assessment results, degradation performance assessment results, and deception protection assessment results to obtain the final test results.

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