Analog detection method and device for communication transmission loop of converter station

Abstract

The application relates to the technical field of extra-high voltage direct current transmission, and discloses a simulation detection method and device for a communication transmission loop of a converter station. The method is characterized in that a plurality of switches are arranged at a communication test interface, inductance regulators and capacitance regulators are connected in series between the switches, and the capacitance regulators are connected in parallel with terminal simulation resistors. First, two test sets are called, the parameter settings of each adjusting component are completed according to the first test set, the first electrical data and the first waveform data are collected after the test interface is connected, and then the second corresponding data are obtained based on the second test set. The electrical attenuation value and the waveform attenuation value are calculated respectively, and then the actual attenuation value is obtained, and the target attenuation value is matched from the attenuation database in combination with the test set. When the actual attenuation value exceeds the target attenuation value, a line abnormality prompt is immediately given. The scheme can simulate the signal attenuation working condition caused by the deterioration of the cable interface, can give an early warning of the line hidden danger, and guarantees the stable operation of the communication transmission loop and the control protection system of the converter station.

Description

Technical Field

[0001] This application relates to the technical field of ultra-high voltage direct current transmission, and in particular to a simulation detection method and device for the communication transmission circuit of a converter station. Background Technology

[0002] Ultra-high voltage direct current (UHVDC) converter stations are a crucial component of the power grid backbone, directly determining the overall power supply stability and safety redundancy level of the power system. As the core control unit of the DC transmission project, the converter station's control and protection system relies heavily on digital transmission links such as serial port connections and network transmission lines for the interactive transmission of various operating commands, status data, and protection signals. The performance of these transmission loops directly affects the response accuracy and operational reliability of the control and protection system.

[0003] Ultra-high voltage direct current converter stations operate under high loads for extended periods. As usage time increases, transmission circuits in the control and execution systems are prone to transmission anomalies. Most transmission anomalies occur at the interface of the cable transmission channel, mainly manifesting as aging, mechanical wear, and surface oxidation of the transmission cables. These defects lead to abnormal impedance in the transmission circuit, increased signal attenuation, and a continuous deterioration in the transmission performance.

[0004] Under the existing operation and maintenance model, the transmission performance degradation caused by the aforementioned interface deterioration is highly concealed. When there are no obvious faults such as data packet errors or signal interruptions on the line, conventional manual inspections, visual inspections, and conventional equipment testing methods cannot effectively identify the hidden performance defects of the link. Only after a clear error occurs in the transmission signal and the system triggers an abnormal alarm can retrospective inspection and troubleshooting be carried out based on the fault error information. Summary of the Invention

[0005] In order to predict potential problems in transmission circuits in advance and to test the transmission performance of transmission circuits, this application provides a simulation testing method and device for communication transmission circuits in converter stations.

[0006] In a first aspect, this application provides a simulation detection method and apparatus for the communication transmission loop of a converter station, employing the following technical solution: A simulation testing method for a converter station communication transmission loop, based on at least one communication test interface for connection to the interface under test, includes: setting up a multi-stage positive switch and a multi-stage negative switch at the communication test interface; setting an inductor regulator and a capacitor regulator in series between the multi-stage positive switch and the multi-stage negative switch; and connecting a terminating analog resistor in parallel with the capacitor regulator; acquiring a first test set and a second test set of the same type; setting up the inductor regulator, capacitor regulator, and terminating analog resistor according to the first test set; connecting the interface under test to the communication test interface; acquiring first electrical data and first waveform data of the terminating analog resistor; obtaining second electrical data and second waveform data based on the second test set; calculating an electrical attenuation value based on the first electrical data and the second electrical data; calculating a waveform attenuation value based on the first waveform data and the second waveform data; calculating an actual attenuation value based on the electrical attenuation value and the waveform attenuation value; matching a target attenuation value from a preset attenuation database based on the first test set and the second test set; and issuing a line anomaly warning if the actual attenuation value is greater than the target attenuation value.

[0007] By adopting the above technical solution, and by adjusting the inductor regulator, capacitor regulator, and terminal analog resistor, the changes in parameters such as cable capacitance to ground and self-inductance can be simulated, and the signal attenuation caused by interface aging, oxidation, and wear can be reproduced. By combining electrical data and waveform data to comprehensively calculate the attenuation value and comparing it with the standard database, it is possible to effectively detect whether the signal attenuation pattern is abnormal, identify hidden defects such as abnormal cable aging in a timely manner, issue early warnings of abnormalities, and ensure the reliable operation of the converter station's communication transmission circuit.

[0008] Optionally, the inductor regulator includes a housing filled with a magnetic fluid liquid, which is a paramagnetic iron oxide particle magnetic fluid. A single-wire spiral wire immersed in the magnetic fluid liquid passes through the housing. A temperature sensor, a semiconductor cooling chip, two end point heat-conducting sheets, and a switching drive are disposed on the housing. The system acquires the actual temperature generated by the temperature sensor and the target temperature of the inductor regulator. It calculates the ratio between the actual temperature and the target temperature as the temperature ratio, and calculates the absolute value of the difference between the temperature ratio and the preset temperature reference value as the temperature control value. If the temperature control value is greater than the preset basic control value, the temperature control mode is entered and the driver is enabled; otherwise, the temperature control mode is exited and the driver is reset. In the reset state, the driver drives the heat-conducting plates at both ends to not contact the semiconductor cooling plate. The cooling power of the thermoelectric cooler is adjusted according to the temperature control value. If the temperature ratio is greater than the preset temperature reference value, the control switching drive will switch the heat-conducting plates at both ends to the cooling contact surface of the thermoelectric cooler; otherwise, the control switching drive will switch the heat-conducting plates at both ends to the heat-conducting contact surface of the thermoelectric cooler.

[0009] By adopting the above technical solution, an inductor regulator is constructed using a spiral wire structure with built-in paramagnetic iron oxide particles and magnetic fluid. This can achieve a high-frequency response of hundreds of megahertz, simulating the self-inductance of high-frequency cables. In conjunction with a temperature sensor, a semiconductor cooling chip, and a switching drive, the cooling power and thermal contact position are dynamically adjusted based on the temperature difference to stabilize the working temperature of the magnetic fluid, ensure stable output of inductance parameters, and further improve the accuracy of simulating the electrical characteristics of cables under high-frequency operating conditions.

[0010] Optionally, the inductance regulator includes multiple series-connected helical wires and an adjustment slider for short-circuiting the helical wires; Obtain the first test set or the second test set, extract inductance data from the first test set or the second test set, obtain the basic inductance data corresponding to the spiral wire, and calculate the total inductance data based on the basic inductance data and the number of spiral wires; The inductance difference is calculated from the total inductance data and the difference between the inductance data. The ratio of the inductance difference to the total inductance data is used as the inductance adjustment value. The distance of the adjustment slider from the initial position on multiple spiral wires is controlled according to the positive correlation of the inductance adjustment value. When the adjustment slider is at the initial position, the inductance value of the inductance regulator is the total inductance data.

[0011] By adopting the above technical solution, an inductance regulator is constructed by using multiple series-connected spiral wires and adjusting sliders. The inductance adjustment value is calculated based on the test set data, and the slider position is controlled to short-circuit the corresponding wire segments, thereby changing the overall inductance value. This allows for continuous and flexible adjustment of inductance parameters to meet different test requirements.

[0012] Optionally, the capacitor regulator includes multiple capacitor groups connected in parallel via a group switching switch. The multiple capacitor groups have the same structure, and each capacitor group is provided with multiple capacitors connected in parallel via a sub-switching switch. The capacitance values ​​of the capacitors in the group are different. Obtain either the first test set or the second test set, extract capacitance data from the first test set or the second test set, and obtain the capacitance value corresponding to the capacitor; calculate the capacitance value of a single capacitor group based on the capacitance value corresponding to the capacitor, and calculate the capacitance group data. The number of capacitor groups is calculated based on the capacitance data and capacitor group data. The product of the capacitor group data and the group data is less than the capacitance data and less than (capacitor group data + 1) and the product of the group data. The capacitor group corresponding to the group data is used as the supplementary capacitor group. The difference between the capacitance data and the product of the capacitor group data is used as the remaining capacitance data. The corresponding capacitor is matched in the capacitor group based on the remaining capacitance data as the supplementary capacitor. Turn on the group switching switch corresponding to the supplementary capacitor group and the sub-switching switch corresponding to the supplementary capacitor.

[0013] By adopting the above technical solution, a hierarchical architecture is used, in which multiple capacitor banks are connected in parallel and capacitors of different capacitance values ​​within each bank are connected in parallel. The required capacitor banks and capacitors are calculated and matched step by step based on the capacitance data of the test set, and the configuration is completed by the corresponding switching switch. This enables the step adjustment of capacitance value and adapts to the capacitance parameter requirements under different test conditions.

[0014] Optionally, the capacitor regulator includes two capacitor electrode plates facing each other and a drive unit that drives one of the capacitor electrode plates to slide, and the drive unit changes the distance between the two capacitor electrode plates after it is activated. Obtain either the first test set or the second test set, extract capacitance data from the first test set or the second test set, and obtain the data corresponding to the capacitance distance to the capacitor electrode plate. The driving distance is calculated based on the capacitance data and the corresponding capacitance distance data, and the driving position of the driving component is controlled based on the positive correlation of the driving distance.

[0015] By adopting the above technical solution, the capacitance value can be changed by adjusting the distance between the relative electrode plates through the driving component. The corresponding driving distance can be calculated based on the capacitance data of the test set and the position of the electrode plates can be controlled, thereby achieving continuous stepless adjustment of the capacitance value.

[0016] Optionally, the step of calculating the electrical attenuation value based on the first electrical data and the second electrical data further includes the following sub-steps: The first electrical data includes multiple first voltage data and multiple first current data that correspond one-to-one. The average value of the multiple first voltage data is calculated as the first voltage value, and the average value of the multiple first current data is calculated as the first current value. The second electrical data includes multiple corresponding second voltage data and multiple second current data. The average value of the multiple second voltage data is calculated as the second voltage value, and the average value of the multiple second current data is calculated as the second current value. The ratio of the first voltage value to the second voltage value is calculated as the voltage ratio, and the ratio of the first current value to the second current value is calculated as the current ratio. A comprehensive ratio is calculated by weighting the voltage ratio and the current ratio, and the difference between the comprehensive ratio and the preset first set ratio is calculated as the electrical attenuation value.

[0017] By adopting the above technical solution, the average value of multiple sets of voltage and current data is taken, and then the comprehensive ratio is obtained by weighting the voltage and current ratios. Finally, the electrical attenuation value is calculated, which can reduce the interference caused by single sampling error, make the electrical parameter calculation results more stable and accurate, and improve the reliability of electrical attenuation detection.

[0018] Optionally, the step of calculating the waveform attenuation value based on the first waveform data and the second waveform data further includes the following sub-steps: Within a preset attenuation time period, first communication data is extracted based on the first waveform data using a preset extraction algorithm, and second communication data is extracted based on the second waveform data using the extraction algorithm. If the first communication data and the second communication data are consistent, the area enclosed by the first waveform data and the coordinate system is calculated as the first area, the area enclosed by the second waveform data and the coordinate system is calculated as the second area, the ratio of the first area and the second area is calculated as the area ratio, and the difference between the area ratio and the preset second set ratio is calculated as the waveform attenuation value; otherwise, the waveform attenuation value is set to the preset maximum waveform attenuation value.

[0019] By adopting the above technical solution, the communication data extracted from the two waveforms are compared first. When the data is consistent, the waveform attenuation value is calculated by the ratio of the waveform areas. If the data is abnormal, it is directly determined as the maximum attenuation value. This not only ensures the accuracy of waveform feature quantification and evaluation, but also quickly identifies serious defects such as signal distortion and data disorder, thereby improving the effectiveness and discrimination efficiency of waveform attenuation detection.

[0020] Optionally, the step of calculating the actual attenuation value based on the electrical attenuation value and the waveform attenuation value further includes the following steps: The electrical attenuation value and the waveform attenuation value are weighted by the initialized weights to calculate the actual attenuation value; Obtain the communication frequency of the interface to be tested, and calculate the ratio between the communication frequency and the preset setting frequency as the frequency ratio. If the frequency ratio is greater than the preset first reference ratio, the weight of the waveform attenuation value is adjusted according to the positive correlation of the frequency ratio; otherwise, the weight is initialized. If the frequency ratio is less than the preset second reference ratio, the weight of the electrical attenuation value is adjusted according to the positive correlation of the frequency ratio; otherwise, the weight is initialized. The first reference ratio is greater than the second reference ratio.

[0021] By adopting the above technical solution, the calculation weights of electrical attenuation value and waveform attenuation value are dynamically adjusted according to the communication frequency of the interface under test. High-frequency conditions focus on waveform characteristic evaluation, while low-frequency conditions focus on electrical parameter evaluation. This approach better reflects the differences in signal transmission characteristics at different frequencies, making the actual attenuation value calculation results more consistent with the on-site working conditions.

[0022] Optionally, the method further includes the following steps: Obtain the communication data volume of the interface to be tested, and calculate the ratio between the communication data volume and the preset data volume as the data volume ratio; If the data volume ratio is greater than the preset first reference ratio, the second reference ratio is adjusted according to the positive correlation of the data volume ratio; otherwise, the second reference ratio is initialized. If the data volume ratio is less than the preset second control ratio, the first reference ratio is adjusted according to the positive correlation of the data volume ratio; otherwise, the first reference ratio is initialized. Among them, the first control ratio is greater than the second control ratio, and the adjusted first reference ratio is greater than the adjusted second reference ratio.

[0023] By adopting the above technical solution, the ratio is calculated based on the amount of communication data and the frequency is dynamically adjusted to determine the reference ratio. Combined with the data transmission load adaptation weight adjustment rule, the transmission characteristics under different data throughput are taken into account, making the attenuation value calculation logic more in line with the actual operating conditions.

[0024] Secondly, this application provides a simulation testing device for the communication transmission loop of a converter station, which adopts the following technical solution: A simulation testing device for a converter station communication transmission loop includes a processor, wherein the processor executes the steps of the simulation testing method for the converter station communication transmission loop as described in any one of the preceding claims.

[0025] In summary, this application includes at least one of the following beneficial technical effects: by coordinating the adjustment of inductance, capacitance, and terminal simulated resistors, it simulates signal attenuation conditions caused by aging, oxidation, and wear of the converter station's communication interface, thereby achieving the detection of hidden defects in the link and early warning of anomalies. This application provides two types of inductor regulators, which can respectively meet the needs of high-frequency response simulation and large-range continuous inductance adjustment; at the same time, it is equipped with a graded combined capacitor structure and an adjustable plate capacitor structure, which can realize step-by-step or continuous stepless adjustment of capacitor parameters, adapting to diverse test scenarios. During the detection process, the electrical attenuation value is calculated by averaging multiple sets of electrical data, and the waveform attenuation value is obtained by combining waveform data comparison and area calculation, effectively reducing sampling errors and quickly identifying signal anomalies; it can also dynamically adjust the calculation weight and judgment threshold according to the communication frequency and data throughput, adapting to different operating conditions, greatly improving the accuracy, rationality, and reliability of attenuation detection results, and ensuring the stable operation of the converter station's communication transmission circuit and control and protection system. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the analog detection circuit of the converter station's communication transmission circuit.

[0027] Figure 2 This is a step diagram of a simulation detection method for the communication transmission loop of a converter station.

[0028] Figure labels: 1. Serial port test interface; 2. Network port test interface; 3. Coaxial cable test interface; 4. Multi-stage positive switch; 5. Multi-stage negative switch; 6. Inductor regulator; 7. Capacitor regulator; 8. Terminating analog resistor; 9. Millivoltmeter; 10. Oscilloscope. Detailed Implementation

[0029] The embodiments of this application are described in detail below, and examples of the embodiments are shown in the accompanying drawings.

[0030] In the description of this specification, the references to "certain embodiments," "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples" refer to specific features, structures, materials, or characteristics described in connection with the described embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0031] This application discloses a simulation testing method for the communication transmission circuit of a converter station, applicable to the routine performance testing, latent degradation identification, and line status prediction of the control and protection communication circuit of an UHVDC converter station. The field communication links of a converter station include various transmission media such as serial communication, network communication, and coaxial high-frequency communication. The distributed inductance, parasitic capacitance, terminal impedance, and signal attenuation characteristics of different interfaces vary significantly. Traditional single-mode testing methods cannot achieve simulation testing of all interfaces and all operating conditions. Therefore, this application configures multiple types of adaptable communication test interfaces, specifically including a serial port test interface 1, a network port test interface 2, and a coaxial cable test interface 3, which can fully cover the mainstream communication interface types to be tested in the converter station. Operating condition simulation is performed for the electrical parameters, transmission frequency, and impedance characteristics of different communication circuits, with reference to… Figure 1 , Figure 2 The hardware topology and testing process shown are illustrated. This simulation testing method includes the following detailed implementation steps: A standardized, parameter-adjustable hardware simulation testing circuit is constructed. Multi-stage positive switches 4 and multi-stage negative switches 5 are configured inside various communication test interfaces. Both multi-stage positive switches 4 and multi-stage negative switches 5 are single-pole multi-stage changeover switches. Serial port test interface 1 can consist of multiple serial port test interfaces 1 with different pin counts connected in parallel. All pins are connected in parallel to form two paths: one path connects to the numbered terminals of each stage of multi-stage positive switch 4, and the other path connects to the numbered terminals of each stage of multi-stage negative switch 5. Network port test interface 2 can be a 4-pin or 8-pin model. Similarly, all pins are connected in parallel to form two paths: one path connects to the numbered terminals of each stage of multi-stage positive switch 4, and the other path connects to the numbered terminals of each stage of multi-stage negative switch 5. The moving contact of multi-stage positive switch 4 is the signal terminal, and the moving contact of multi-stage negative switch 5 is the ground terminal, both connected in parallel to the neutral point and ground terminal of coaxial cable test interface 3, respectively. Between the main test circuit consisting of multi-stage positive switch 4 and multi-stage negative switch 5, an inductor regulator 6 and a capacitor regulator 7 are connected in series, forming a line distributed parameter simulation unit. The inductor regulator 6 simulates the distributed self-inductance characteristics of the converter station's communication cables, while the capacitor regulator 7 simulates the cable's parasitic capacitance to ground and the distributed capacitance characteristics of the interfaces, realistically simulating the inductance and capacitance parameter deviations caused by line aging, wear, moisture, and oxidation. Simultaneously, a terminating analog resistor 8 is connected in parallel across the capacitor regulator 7 to simulate the terminating impedance of the communication transmission circuit, ensuring that the impedance matching state and signal transmission characteristics of the test circuit are consistent with the actual operating circuit in the field, guaranteeing the equivalence and realism of the simulated test conditions. The analog detection circuit also includes a millivoltmeter 9 and an oscilloscope 10. The millivoltmeter 9 is connected in parallel across the terminal analog resistor 8 to acquire and display the steady-state voltage amplitude of the circuit, providing first and second electrical data for calculating the electrical attenuation value. The oscilloscope 10 is connected in parallel with the millivoltmeter 9 to acquire and display the time-domain waveform across the terminal analog resistor 8 in real time, providing first and second waveform data for calculating the waveform attenuation value. The multi-stage positive switch 4 and multi-stage negative switch 5, and the capacitor bank switching switch employ a break-before-make mechanism with a switching interval ≥20ms and anti-jitter delay.

[0032] After the hardware loop is set up, the system retrieves two sets of standard test sets of the same type that are preset and stored in the attenuation database, defined as the first test set and the second test set, respectively. Both test sets correspond to the same type of communication interface, the same communication frequency band, and the same cable specification. Parameter dimensions include standard inductance parameters, standard capacitance parameters, terminal matching resistor parameters, reference electrical parameters, and standard waveform characteristic parameters. The first test set is a baseline test set for a perfectly intact line, corresponding to the parameters of a brand-new, undegraded, and fault-free standard communication line. The second test set is a comparative baseline test set (with the upper limit of allowable degradation), used to construct a differential comparison baseline, providing a reference for subsequent attenuation quantification calculations. The parameters of both test sets have been calibrated through extensive field testing and simulation, ensuring compatibility with operating conditions.

[0033] The system prioritizes loading the first test set. Based on the standard parameters calibrated within the first test set, it sequentially completes the parameter tuning and calibration of inductor regulator 6, capacitor regulator 7, and terminal analog resistor 8, ensuring that the electrical parameters, impedance characteristics, and transmission characteristics of the current hardware simulation circuit match the operating state of the standard line. After the parameters are configured and stabilized for 2-3 seconds, the communication interface to be tested at the converter station is connected to the corresponding type of communication test interface to form a closed-loop simulation test circuit. Once the signal transmission state of the circuit is stable and free from fluctuations and interference, the system synchronously collects the operating parameters on the terminal analog resistor 8, acquiring the first electrical data and the first waveform data, and records the steady-state electrical characteristics and dynamic waveform transmission characteristics under standard and intact operating conditions, respectively.

[0034] After completing the first set of data acquisition, the system switches to load the second test set, keeping the detection environment, sampling frequency, sampling accuracy, and loop wiring status unchanged. Based on the preset parameters of the second test set, the operating parameters of the inductor regulator 6, capacitor regulator 7, and terminal analog resistor 8 are readjusted to simulate a baseline operating condition where the circuit exhibits normal degradation and offset. Once the loop parameters stabilize, the same sampling mechanism as described above is used to acquire the second electrical data and second waveform data corresponding to the terminal analog resistor 8, constructing a dual-condition comparison dataset.

[0035] After acquiring two sets of comparative data, the system quantifies the line attenuation level bidirectionally from both electrical and waveform dimensions. Specifically, by performing mean filtering, ratio calculation, and weighted fusion on the first and second sets of electrical data, the system obtains the electrical attenuation value corresponding to steady-state transmission loss, which characterizes the voltage and current amplitude losses and steady-state power losses caused by line impedance shifts. By performing symbol verification, discrete integral area comparison, and benchmark difference calculation on the first and second waveform data, the system obtains the waveform attenuation value corresponding to dynamic transmission distortion, which characterizes dynamic transmission defects such as high-frequency loss, waveform distortion, phase shift, and edge distortion. Based on this, the system adaptively adjusts the fusion weights of the electrical attenuation value and the waveform attenuation value according to the communication frequency and communication data volume under the current operating conditions, and calculates the actual attenuation value that can comprehensively characterize the overall degradation level of the line, achieving multi-condition adaptive quantization.

[0036] The system searches and matches the current detection interface type, communication frequency band, and matched first and second test sets in a preset attenuation database, retrieving the maximum allowable attenuation threshold for this type of communication loop under this operating condition as the target attenuation value. The attenuation database is a standardized database established through extensive field measurements, simulation fitting, and operating condition calibration. It covers standard target attenuation thresholds for different interfaces, frequencies, service years, and load conditions, and is adaptable to various testing scenarios.

[0037] The system compares the actual attenuation value calculated in real time with the target attenuation value matched in the database to determine the threshold: when the actual attenuation value is greater than the target attenuation value, it is determined that the signal attenuation of the current converter station's communication transmission circuit exceeds the standard, and the line has deterioration defects such as interface oxidation, poor contact, cable aging, decreased insulation performance, and implicit impedance drift. The system immediately triggers a line abnormality prompt and notifies the operation and maintenance personnel through audible and visual prompts, background message pop-ups, etc., to achieve early warning of implicit faults; if the actual attenuation value is less than or equal to the target attenuation value, it is determined that the current line transmission performance meets the standard operating requirements, there is no abnormal deterioration risk, and the line is operating normally.

[0038] Based on the aforementioned method for simulating and detecting the communication transmission circuit of a converter station, this application provides two differentiated preferred implementation structures for the inductor regulator 6 of the detection circuit: a magnetic fluid temperature-controlled adjustable inductor structure and a segmented spiral wire slider adjustable inductor structure. The magnetic fluid temperature-controlled inductor is suitable for high-frequency, high-precision, and low-fluctuation coaxial and Ethernet communication circuit parameter simulation scenarios, effectively eliminating the interference of temperature drift on inductor parameters. The segmented spiral wire slider inductor is suitable for low-to-medium frequency, wide-range, and high-stability serial communication circuit parameter simulation scenarios, featuring strong mechanical stability, excellent adjustment linearity, and no high-frequency temperature drift. Both structures can be flexibly adapted according to the type of interface to be tested, communication frequency, and line degradation degree, effectively improving the simulation accuracy of the distributed inductor parameters of the converter station's communication transmission circuit. The following details the two implementation methods: The first type: Magnetic fluid temperature-controlled adjustable inductor regulator 6 In this embodiment, the inductor regulator 6 adopts an integrated structure combining magnetic fluid electromagnetic control with semiconductor isothermal compensation, enabling continuous adjustment of inductance parameters under high-frequency operating conditions. Specifically, the inductor regulator 6 is equipped with a sealed insulating outer shell, the interior of which is a closed cavity structure completely filled with magnetic fluid. In this embodiment, paramagnetic iron oxide particle magnetic fluid is selected as the magnetic conductive medium. This type of magnetic fluid has the advantages of stable magnetic permeability, low high-frequency loss, fast magnetization response speed, and wide temperature adaptation range. It exhibits no significant electromagnetic parameter distortion under high-frequency signal conditions of 0–300MHz, and can replicate the distributed self-inductance characteristics of high-frequency communication cables in converter stations.

[0039] A single-wire helical conductor runs through the interior of the casing, completely immersed in the magnetofluid and fully coupled with the medium. By altering the magnetic flux around the helical conductor through the magnetization properties of the magnetofluid, the overall equivalent inductance is continuously adjusted, achieving stepless continuous adjustment of the inductance parameter. To achieve closed-loop control of the operating temperature, a temperature sensor, a semiconductor cooling chip, heat-conducting plates at both ends, and a switching drive are integrated into the outer wall of the casing. These components work together to form a closed-loop temperature control system, ensuring that the magnetofluid is always within its optimal operating temperature range.

[0040] During the specific temperature control process, the system acquires the actual internal temperature of the inductor regulator 6 in real time from the temperature sensor. At the same time, the optimal target operating temperature of the inductor regulator 6 preset by the system is retrieved. This embodiment is calibrated. 25℃ is the reference temperature at which the magnetic properties of magnetohydrodynamics are most stable. The system obtains the temperature ratio through ratio calculation. The calculation formula is: The system has a preset fixed temperature reference value. The value is 1.0, used to determine temperature deviation from the reference value. The temperature control value ΔT is obtained by calculating the absolute value of the difference between the temperature ratio and the temperature reference value. The calculation formula is as follows: .

[0041] The system internally presets a basic control value as the temperature control start threshold; in this embodiment, the preferred basic control value is 0.03. When the calculated temperature control value ΔT > 0.03, it is determined that the current operating temperature of the inductor regulator 6 deviates from the standard allowable range, the magnetic permeability of the magnetohydrodynamic fluid shifts, which can easily lead to distortion of the simulated inductor parameters. The system automatically enters the temperature control mode and enables the switching of the driving device, initiating the temperature compensation adjustment process. When ΔT ≤ 0.03, it is determined that the current temperature is within a reasonable error range, and the influence of temperature on the inductor parameters is negligible. The system exits the temperature control mode and resets the switching of the driving device. After exiting temperature control, the temperature is re-acquired and ΔT is calculated every 10 seconds; if ΔT > 0.03, the system automatically re-enters the temperature control mode. In the driver reset state, the heat-conducting plates at both ends are completely separated from the semiconductor cooling chip, with no heat exchange contact. The semiconductor cooling chip is in a low-power standby state and has no temperature adjustment action.

[0042] In temperature-controlled operation, the cooling power of the thermoelectric cooler is linearly and positively correlated with the temperature control value. The greater the temperature deviation, the higher the cooling compensation power, achieving adaptive power adjustment. The specific power adjustment formula is as follows: Where P is the baseline standby cooling power, which is 5W, and the maximum cooling power of the system is limited to 30W, which can cover the temperature deviation adjustment needs of all operating conditions.

[0043] Simultaneously, the system switches the heat exchange mode according to the temperature ratio to achieve temperature control: if the temperature ratio is... A temperature ratio >1.0 indicates that the actual internal temperature of the device is higher than the reference temperature, and the magnetofluid is in a high-temperature deterioration state with decreased permeability. At this point, the control switch actuator activates, driving the heat-conducting plates at both ends to contact the cooling surface of the semiconductor cooling chip, rapidly absorbing heat from the cavity and achieving rapid cooling. If the temperature ratio is... ≤1.0 indicates that the internal temperature of the device is too low and the magnetization activity of the magnetic fluid is insufficient. At this time, the control switching drive will switch the heat-conducting plates at both ends to the heat-conducting contact surface of the semiconductor cooling chip, and use the residual heat of the device to achieve the cavity temperature recovery. Finally, the working temperature of the inductor regulator 6 is stabilized in a high-precision constant temperature range of 25℃±0.5℃.

[0044] The second type: Segmented spiral wire slider-type adjustable inductor regulator 6 This embodiment discloses another structural form of inductor regulator 6, suitable for simulating inductance parameters in low-frequency communication transmission circuits in converter stations. It possesses advantages such as stable mechanical structure, high adjustment linearity, good parameter repeatability, and no temperature drift interference. It can simulate large-scale self-inductance parameter deviations caused by cable aging, wear, and oxidation. Specifically, the inductor regulator 6 is composed of multiple segments of uniformly sized, consistent-parameter spiral wires connected in series, forming a segmented inductor array. Each segment of the spiral wire is an independent standardized inductor unit, with consistent parameters and uniform arrangement. Simultaneously, a linearly sliding adjustment slider is provided. The adjustment slider has a metal short-circuit conduction function, selectively short-circuiting a portion of the series-connected spiral wires to change the number of effective inductor units connected to the circuit, thereby achieving overall inductance value adjustment.

[0045] In this preferred embodiment, the basic inductance data of a single-segment spiral conductor The inductance regulator is calibrated to 1μH and integrates 10 series-connected spiral conductors, with a total maximum inductance range of 10μH, covering the cable distribution inductance variation range of the converter station's serial port and low-speed network communication circuits. When the adjusting slider is at its initial zero displacement position, all spiral conductors are not short-circuited and are all connected to the detection circuit. At this time, the output inductance value of the inductance regulator 6 is the total inductance data. In this embodiment It is 10 μH.

[0046] During the specific parameter adjustment process, the system first retrieves the first or second test set corresponding to the current detection task, and extracts the target inductance data required for the current operating condition from the test set. The system retrieves pre-stored basic inductance data for a single segment of spiral wire and the total number of wires, and calculates the total inductance data. The system then calculates the difference between the total inductance data and the target inductance data to obtain the inductance difference ΔL. The calculation formula is as follows: The standardized inductance adjustment value is obtained by further calculating the ratio of the inductance difference to the total inductance data. The calculation formula is: , The value range is [0, 1), and the upper limit of the project is set to 0.9 to avoid the slider from being blocked and short-circuited.

[0047] In this scheme, the sliding distance of the slider is linearly and positively correlated with the inductance adjustment value, achieving quantitative control. The system presets the maximum effective sliding stroke of the slider. The actual sliding distance of the slider is calculated as follows: (The value is 50mm) A larger inductance adjustment value means more inductor units need to be short-circuited, a longer slider distance, and a smaller effective inductance in the circuit; conversely, a smaller inductance adjustment value means a shorter slider distance and a larger effective inductance in the circuit.

[0048] Based on the aforementioned method for simulating and detecting the communication transmission circuit of a converter station, this application also provides two preferred implementation structures for the capacitor regulator 7 in the detection circuit, which can be applied independently and adapted to different detection scenarios: a multi-group parallel graded switching capacitor regulator 7 and a plate-sliding stepless adjustable capacitor regulator 7. The graded switching capacitor regulator 7 is suitable for simulating large-scale, stepped capacitance to ground, and parasitic capacitance degradation conditions of communication cables, and features a large range, rich range options, and strong anti-interference capability. The plate-sliding stepless adjustable capacitor regulator 7 is suitable for simulating minor capacitance parameter deviations caused by slight line aging and environmental temperature drift. The two structures work together to cover the capacitance parameter simulation requirements of various communication interfaces in the converter station, including serial ports, network ports, and coaxial cables. Specific implementation methods are as follows: Type 1: Multi-group parallel graded switching capacitor regulator 7 In this embodiment, the capacitor regulator 7 adopts a hierarchical array structure of "multiple parallel groups and multiple specifications within each group in parallel". It achieves a wide-range, high-precision range of capacitor parameter output through graded switching, adapting to the combined simulation requirements of coarse and fine adjustment of capacitor parameters in the converter station communication circuit. Specifically, the capacitor regulator 7 is configured with multiple capacitor groups of identical structural specifications and electrical parameters. Each capacitor group is independently connected in parallel, and each group is equipped with an independent group switching switch. By controlling the on / off state of the group switching switch, single or multiple capacitor groups can be connected or disconnected in parallel, achieving a wide range of coarse adjustment of capacitor parameters.

[0049] Each capacitor bank integrates multiple independent capacitors, each with its own dedicated sub-switch. These capacitors are connected in parallel within the bank via their respective sub-switches. The rated capacitance values ​​of the capacitors within the same bank are different, employing a gradient capacitance configuration to create complementary capacitance combinations, compensating for minute capacitance differences. In this preferred embodiment, each capacitor bank contains three standard capacitors with rated capacitance values ​​of 100pF, 20pF, and 5pF, respectively. The full capacity of a single capacitor bank when fully engaged is 125pF. The system comprises a total of eight identical capacitor banks, with a maximum adjustable capacitance of 1000pF, covering the 50pF to 1000pF range of distributed capacitance and parasitic capacitance to ground for conventional communication lines in the converter station.

[0050] Based on the standardized execution of the parameter matching and switching control process of the capacitor regulator 7, the specific steps are as follows: When the system performs line simulation testing, it first retrieves the first or second test set corresponding to the current testing task, and extracts the target capacitance data required for the current operating condition from the standard parameters built into the test set. The target capacitance data is the standard equivalent capacitance value corresponding to a specific degree of degradation of the simulated communication line. The system retrieves the pre-stored calibration values ​​of each capacitor and calculates the total capacity of a single capacitor bank under full switching conditions through cumulative calculation, which is defined as the capacitor bank data. In this embodiment It is 125pF.

[0051] To achieve matching of large-capacity base capacitors, the system performs integer division adaptation calculations between the target capacitor data and the capacitor bank data to determine the required number of base capacitor banks, defined as bank data n, following the numerical matching constraints specified in this application: The system identifies all capacitor banks of quantity n as basic input units, defines them as supplementary capacitor banks, and completes a large-scale coarse matching of the target capacitor capacity by connecting multiple capacitor banks in parallel.

[0052] After the basic capacitor bank matching is completed, there are still some minor capacitance differences in the target capacitance data that cannot be covered by the entire capacitor bank. The system then performs further fine-tuning compensation calculations. The remaining capacitance data ΔC is obtained by subtracting the total capacity of n capacitor banks from the target capacitance data. The calculation formula is as follows: The remaining capacitance data represents the slight capacitance difference that needs to be compensated. Based on the remaining capacitance data ΔC, the system performs optimal combination matching among multi-gradient capacitors in a single capacitor group, selecting capacitors that can fit the remaining capacitance data and defining them as supplementary capacitors to compensate for the slight capacitance deviation. Matching rules: Prioritize selecting the capacitor with the smallest error between its individual capacitance value and the remaining capacitance data; if the error exceeds a preset threshold, use a parallel combination of multiple capacitors for matching.

[0053] After completing the dual matching of the basic capacitor bank and the compensation capacitor, the system executes the switch switching control logic, uniformly turning on the group switching switches corresponding to all supplementary capacitor banks, so that the n capacitor banks are connected in parallel to the detection circuit. At the same time, the sub-switching switches corresponding to the matched supplementary capacitors are turned on to connect the compensation capacitors to the circuit. All other group switching switches and sub-switching switches that did not participate in the matching are kept in the open state to prevent excess capacitor capacity from causing parameter deviation.

[0054] The second type: Plate sliding steplessly adjustable capacitor regulator 7 Another preferred embodiment provides a stepless continuously adjustable capacitor regulator 7 based on the adjustment of parallel plate spacing. Unlike the aforementioned graded adjustment structure, this structure can realize the capacitor parameters without grade, gap, and continuous smooth adjustment. It is specially adapted to the slight capacitor drift caused by slight aging of the converter station communication line, environmental temperature change, and slight change in insulation performance. It can effectively detect hidden slight deterioration defects that cannot be identified by conventional grade adjustment.

[0055] Structurally, the capacitor regulator 7 consists of two parallel capacitor electrode plates facing each other and a linear drive component. The two capacitor electrode plates form a standard parallel plate capacitor structure. One capacitor electrode plate is a fixed plate, rigidly mounted and its position remains unchanged. The other capacitor electrode plate is a movable plate, fixedly connected to the output end of the drive component. By linearly sliding the drive component, the relative distance between the two capacitor electrode plates can be continuously changed. Based on the physical principle of parallel plate capacitors, under the premise of constant dielectric, the plate distance and the equivalent capacitance value have a monotonically negative correlation. The smaller the plate distance, the larger the equivalent capacitance value; the larger the plate distance, the smaller the equivalent capacitance value. This achieves continuous stepless adjustment of the capacitance parameter.

[0056] This embodiment standardizes and calibrates the device parameters, fixes the effective facing area of ​​the plates, uses air as the dielectric, and sets the effective adjustment range of the plate spacing to 2mm to 20mm, corresponding to a standard capacitor adjustment range of 50pF to 500pF, covering the range of minor capacitance drift in the circuit. The system internally stores a capacitance-distance correspondence data table pre-fitted through multi-point calibration, establishing a one-to-one correspondence between the plate spacing and the output capacitance value.

[0057] During the specific operating condition adjustment process, the system first retrieves the first or second test set corresponding to the current detection, and extracts the target capacitance data required for the current operating condition from the test set. The system retrieves pre-stored data corresponding to capacitor distances and, combined with the parallel plate capacitor fitting relationship, quantitatively calculates the required driving distance L for the movable plate. To ensure adjustment and control effectiveness, this embodiment employs linear fitting quantization control logic. Within the effective range, the driving distance and capacitor adjustment amount exhibit a strictly positive correlation, achieving controllable adjustment.

[0058] The specific conversion formula for this scheme is as follows: ,in, The minimum capacitance value for the measurement range is 50pF, and k is the calibration scaling factor. In this embodiment, k = 0.04mm / pF. Based on the parallel plate capacitance formula... After calibrating the effective area of ​​the electrode plate, the dielectric, and the range (2-20mm, 50-500pF), the proportional coefficient is derived. .

[0059] As can be seen from the formula, the larger the target capacitance value, the greater the required driving distance, the longer the sliding stroke of the movable plate, and the smaller the plate spacing. This conforms to the physical characteristics of parallel plate capacitors, and the driving distance is linearly positively correlated with the increase in the target capacitance. The control logic is clear and the linearity is high.

[0060] Meanwhile, the system is equipped with interval limit protection logic, strictly limiting the sliding stroke of the drive component within the effective range of 2mm to 20mm to avoid abnormal operating conditions such as plate contact collisions and overtravel derailment, ensuring long-term stable operation of the equipment. Through this stepless adjustment structure, it can output any continuous capacitance parameter within the range of 50pF to 500pF without step error, simulating subtle operating conditions such as weak capacitance degradation and parameter drift in the converter station communication circuit, thus compensating for the shortcomings of the graded switching capacitor regulator 7 in fine parameter adjustment.

[0061] In the converter station communication transmission loop simulation detection method of this application, the electrical attenuation value is a quantitative indicator for quantifying the steady-state transmission loss and impedance degradation of the communication line. It can characterize the voltage and current amplitude attenuation and power transmission loss caused by defects such as cable aging, interface oxidation, terminal loosening, increased contact resistance, and line parasitic parameter deviation. To overcome the shortcomings of traditional single-point sampling calculation methods, which are easily affected by on-site electromagnetic interference, instantaneous signal jitter, and random sampling noise, resulting in large fluctuations, poor repeatability, and low judgment accuracy in attenuation calculation results, this application optimizes and refines the calculation logic of the electrical attenuation value. It adopts a hierarchical calculation method of multi-point synchronous sampling mean filtering, dual electrical dimension feature ratio extraction, standardized weighted fusion, and benchmark difference quantification, which effectively improves the stability, accuracy, and engineering feasibility of the electrical attenuation quantification results. Specifically, it includes the following sub-steps: In this embodiment, the first electrical data is the original electrical sampling dataset collected by the communication circuit under test under standard and intact reference conditions. To avoid sampling distortion caused by transient interference, the system adopts a high-frequency continuous multi-point synchronous sampling mechanism, continuously collecting multiple sets of time-corresponding first voltage and first current data within a single detection cycle to ensure that the voltage and current data are time-aligned and consistent under operating conditions. In this embodiment, the preferred number of sampling points per operating condition is N=20, and the sampling interval is set to 1ms, covering the steady-state transmission cycle of the communication signal. After the acquisition is completed, the system performs an arithmetic mean filtering calculation on multiple sets of first voltage data, removes accidental abnormal pulse sampling points, and calculates the steady-state mean. The calculation result is defined as the first voltage value. The specific calculation formula is as follows: Similarly, the system calculates the average of multiple sets of synchronously acquired first current data to obtain a first current value that can characterize the steady-state transmission characteristics under standard operating conditions. The specific calculation formula is as follows: .

[0062] Correspondingly, the second electrical data is an electrical dataset synchronously collected from the communication circuit under simulated harsh operating conditions. The acquisition duration, sampling frequency, number of sampling points, and equipment sampling gain are consistent with the first electrical data to ensure strict horizontal comparability between the two sets of data. The second electrical data includes multiple sets of time-series corresponding second voltage and second current data. The system uses the same mean filtering algorithm as under standard operating conditions to calculate the steady-state mean of multiple sets of second voltage data to obtain the second voltage value. The calculation formula is: The steady-state mean value of the second current is obtained by solving multiple sets of second current data. The calculation formula is: By using multi-point mean filtering, random noise and instantaneous fluctuation errors in the complex electromagnetic environment of the converter station can be effectively filtered out, ensuring that the voltage and current values ​​used in the final calculation can truly reflect the steady-state transmission characteristics of the line.

[0063] Based on the physical mechanism of communication transmission, when a communication transmission circuit suffers from deterioration defects such as aging, poor contact, or impedance shift, the overall equivalent impedance of the circuit increases, leading to increased power loss during signal transmission. This directly manifests as a significant attenuation of the steady-state voltage and current amplitude at the output terminal. Therefore, under the same test conditions and the same signal source excitation, the electrical parameters corresponding to the standard good operating condition are always greater than those corresponding to the deteriorated operating condition, i.e., they consistently satisfy... > , > Based on this characteristic, the system constructs dimensionless attenuation characteristic ratios to quantify the independent losses of voltage and current. Among these, the voltage ratio... The ratio of the average voltage under standard operating conditions to the average voltage under adverse operating conditions is calculated using the following formula: Current ratio The ratio of the average current under standard operating conditions to the average current under adverse operating conditions is calculated using the following formula: The voltage ratio obtained from this Current ratio The ratio is always greater than 1, and the larger the ratio value, the more severe the transmission loss in the corresponding dimension and the higher the degree of line degradation.

[0064] To avoid the bias of judging solely by voltage or current dimensions, this application employs a dual-dimensional, equally weighted fusion method to calculate the comprehensive ratio K. Considering the steady-state loss characteristics of the converter station's communication transmission circuit, the impact of voltage amplitude loss and current amplitude loss on line performance is weighted equally. Therefore, a voltage weighting coefficient α = 0.5 and a current weighting coefficient β = 0.5 are set, satisfying the normalization constraint α + β = 1. The specific formula for calculating the comprehensive ratio is as follows: Weighting basis: power The overall attenuation is approximated as an equivalent fusion of voltage and current attenuation, with equal weights applied for engineering simplification (α=β=0.5). This fusion method effectively integrates the dual characteristics of voltage and current losses, comprehensively reflecting the overall electrical degradation state of the transmission circuit and improving the completeness and reliability of the quantitative assessment.

[0065] The system has a pre-set ratio that adapts to different interface types, communication frequencies, and cable specifications. The first set ratio is a critical threshold obtained through extensive field tests, simulation calibration, and long-term operational data statistics. It represents the maximum comprehensive attenuation ratio of the communication line within the allowable service error range, serving as a criterion for distinguishing between normal line loss and abnormal degradation. The system calculates the difference between the weighted and fused comprehensive ratio and the first set ratio to obtain the standardized electrical attenuation value ΔK, calculated using the following formula: .

[0066] When abnormal transmission attenuation occurs on the line, the overall ratio K is always greater than the baseline critical ratio. Therefore, the calculated electrical attenuation value ΔK is always greater than 0. The smaller the value of ΔK, the closer the line electrical loss is to the normal standard and the better the line operation. The larger the value of ΔK, the more serious the line impedance distortion, the higher the steady-state power loss, and the more prominent the defects such as cable aging, poor interface contact, and latent parameter drift.

[0067] This embodiment discloses a method for calculating waveform attenuation values, used to quantify the dynamic transmission degradation degree of the converter station's communication transmission circuit from the signal waveform dimension. The aforementioned electrical attenuation values ​​are mainly based on steady-state voltage and current amplitudes to assess steady-state line loss, which is insufficient to identify dynamic latent defects such as signal edge distortion, waveform amplitude compression, high-frequency energy loss, and subtle phase shifts. Therefore, this application adds a waveform feature comparison and waveform energy integration judgment mechanism. By combining code data consistency pre-verification with waveform area energy comparison, it distinguishes between severe line distortion faults and minor energy attenuation degradation, achieving the quantification of dynamic transmission performance and compensating for the lack of dimension in pure electrical parameter detection. The specific sub-steps are as follows: The system pre-calibrates a fixed attenuation time period, which is set according to the transmission cycle of the converter station's communication symbols. Ideally, this attenuation time period should fully cover the transmission duration of at least two sets of communication logic symbols, ensuring that the captured waveform data contains complete logic transition characteristics and steady-state amplitude characteristics, avoiding feature omissions or analysis distortions due to insufficient capture time. Within the preset attenuation time period, the system performs standardized communication data extraction operations on the collected and stored first and second waveform data, respectively. The first waveform data corresponds to continuous time-domain waveform sampling data under standard, healthy operating conditions, while the second waveform data corresponds to continuous time-domain waveform sampling data under simulated line deterioration conditions.

[0068] This application employs a pre-defined extraction algorithm adapted to the digital communication signals of converter stations to demodulate and extract communication data. This algorithm eliminates the need for complex spectrum calculations, extracting digital symbols solely through level threshold judgment and differential edge recognition, and is compatible with various digital communication signals such as serial ports, Ethernet ports, and differential buses. The specific extraction logic includes: the system has built-in fixed high-level and low-level thresholds; it performs level judgment on the amplitude of each sampling point of the continuous analog waveform; values ​​above the high-level threshold are identified as logic level "1", and values ​​below the low-level threshold are identified as logic level "0"; simultaneously, it captures waveform transition edges through differential amplitude calculation of adjacent sampling points, correcting misjudgments caused by waveform jitter, and finally outputs the serial digital symbol sequence carried by the waveform, obtaining the first communication data corresponding to the first waveform data and the second communication data corresponding to the second waveform data, thus realizing the conversion from analog waveform to valid digital communication data.

[0069] The system performs a bit-by-bit code element consistency comparison and verification between the extracted first and second communication data, and determines the fault level based on the comparison results. If the first and second communication data are inconsistent, it indicates that the transmission waveform under the degraded operating conditions has suffered severe distortion, code element flipping, signal distortion, transmission errors, and other fatal defects, and the communication link can no longer accurately transmit valid service data, which is a serious transmission failure fault. To uniformly quantify this type of extreme degraded operating condition, the system directly assigns the waveform attenuation value of the current operating condition to the system's preset maximum waveform attenuation value. (In practical applications, if the bit error rate is >1%, the maximum waveform attenuation value is set; otherwise, the waveform attenuation value is calculated linearly weighted by the bit error rate.) The maximum waveform attenuation value is an experimentally calibrated upper limit threshold for attenuation, used to characterize the extreme state of complete waveform transmission failure and severe attenuation exceeding the limit, eliminating the need for subsequent integral calculations and improving the efficiency of serious fault determination.

[0070] If the first communication data and the second communication data are completely identical, it indicates that there are no serious distortion problems such as bit errors or symbol corruption in the current transmission loop, and the communication service data can be transmitted normally and accurately. There are only subtle, hidden degradations that are difficult to detect manually, such as overall waveform amplitude attenuation, waveform transmission energy loss, and minor waveform distortion. At this time, the system starts waveform energy quantization calculation, and the total signal transmission energy is represented by the area enclosed by the waveform and the coordinate system.

[0071] Since the waveform data acquired by the device consists of discrete time-domain sampling points, this application employs a practical discrete trapezoidal integral algorithm to calculate the effective area of ​​the waveform. The total number of sampling points within the decay time period is set to M, the sampling time interval is fixed at Δt, the amplitude of the first waveform corresponding to the i-th sampling point is y, and the amplitude of the second waveform corresponding to the i-th sampling point is yi. The system calculates the total area enclosed by the first waveform data and the time coordinate system through integration, which is defined as the first area. The total energy of signal transmission under standard operating conditions is represented by the following formula: .

[0072] Simultaneously, the system employs a completely consistent integration algorithm, sampling interval, and calculation parameters to solve for the total area enclosed by the second waveform data and the time coordinate system, which is defined as the second area. The total energy of signal transmission under adverse chemical conditions is characterized by the following formula: Based on the physical characteristics of signal transmission, under conditions of impedance loss and high-frequency attenuation in the line, signal energy is absorbed by line losses. In degraded operating conditions, the overall amplitude of the waveform decreases and energy attenuates. Therefore, the constant requirement must be met. > .

[0073] The system constructs a dimensionless area ratio by comparing the first area with the second area. This is used to uniformly quantize the degree of waveform energy attenuation, and the calculation formula is: The area ratio is always greater than 1, and the more severe the line degradation and the higher the waveform energy loss, the higher the area ratio. The larger the value, the better. The system has a pre-set second ratio that adapts to different communication frequencies and interface types. The second set ratio is the critical threshold for normal waveform attenuation obtained from a large number of field calibrations and simulation tests, which serves as the criterion for distinguishing between normal slight loss and abnormal degradation of the waveform.

[0074] The system calculates the difference between the real-time calculated area ratio and the second set ratio to obtain the final standardized waveform attenuation value ΔK. The calculation formula is as follows: Under slightly degraded conditions with consistent code data, the real-time area ratio is always greater than the baseline critical ratio, therefore the waveform attenuation value ΔK is always greater than 0. The magnitude of this waveform attenuation value is positively correlated with waveform energy loss and waveform distortion, which can quantify the implicit transmission degradation defects of the line under error-free conditions, forming a bidirectional complementary detection system for steady-state electrical loss and dynamic waveform loss with the aforementioned electrical attenuation value.

[0075] This application calculates two types of quantitative indicators—electrical attenuation and waveform attenuation—through the aforementioned steps. The electrical attenuation value primarily characterizes the steady-state voltage and current amplitude losses caused by impedance shifts in the communication loop, suitable for degradation assessment in low-frequency steady-state transmission scenarios. The waveform attenuation value primarily characterizes dynamic transmission defects caused by high-frequency line losses, signal distortion, energy attenuation, and edge distortion, suitable for degradation assessment in high-frequency transient transmission scenarios. To avoid the one-sidedness of single-dimensional assessment and to quantify the overall degradation degree of the line under all frequency operating conditions, this embodiment discloses a method for calculating the actual attenuation value based on adaptive weight correction of the communication frequency. This method dynamically and adaptively adjusts the calculation weights of the two attenuation indicators according to the actual communication frequency shift characteristics of the interface under test, ensuring that the final output actual attenuation value closely matches the actual transmission mechanism of the converter station communication loop. The specific implementation steps are as follows: This method pre-configures standardized initialization weights as parameters for fusion calculations under normal baseline conditions. Specifically, it sets the electrical attenuation initialization weights. Waveform attenuation initialization weights And the two types of weights satisfy the normalization constraint: In this preferred embodiment, for the intermediate frequency standard communication conditions of the converter station, a balanced weight configuration method is adopted, and the following settings are made: 0.5 The value is set to 0.5 to ensure a balanced assessment ratio between electrical steady-state losses and waveform dynamic losses under standard operating conditions, thereby improving the objectivity and stability of the baseline assessment. Without triggering frequency adaptive adjustment, the system defaults to using the initialized weights to perform a weighted fusion calculation of the actual attenuation values.

[0076] To achieve adaptive correction based on operating conditions, the system collects the actual operating communication frequency f of the interface under test in real time. This frequency represents the dominant frequency parameter of the current communication service signal, accurately reflecting the real-time transmission conditions of the loop. The system retrieves the preset standard setting frequency. This set frequency is the rated reference frequency adapted to various communication interfaces of the converter station, and serves as the calibration benchmark for determining the degree of frequency deviation. The system quantifies the degree of deviation of the current operating condition relative to the standard operating condition through ratio calculation, and calculates the frequency ratio. The specific calculation formula is as follows: .in, This is a dimensionless offset coefficient used to drive subsequent adaptive weight adjustment logic.

[0077] The system has two preset hierarchical frequency determination thresholds, namely the first reference ratio. Ratio to the second reference And strictly satisfy the hierarchical constraints: > This divides the operating conditions into three independent segments: a high-frequency offset range, a standard mid-frequency range, and a low-frequency offset range, enabling differentiated weight adjustment for each segment. This embodiment has undergone extensive field calibration and has been optimized. 1.2 The value is 0.8, completing the interval division for all frequency operating conditions.

[0078] The system executes high-frequency operating condition weighted adaptive adjustment logic: when the calculated frequency ratio >First Reference Ratio When the interface under test is in a high-frequency communication condition, it is determined that the interface is currently in a high-frequency communication condition. During high-frequency signal transmission, waveform distortion, high-frequency energy loss, and phase shift caused by line parasitic parameters are the main degradation characteristics, and the influence of waveform attenuation index on line performance is weighted higher. This application follows the adjustment rule that the frequency ratio and waveform attenuation weight are linearly positively correlated, that is, the larger the frequency ratio and the higher the operating frequency, the greater the waveform attenuation weight, matching the transmission characteristics dominated by waveform loss in high-frequency operating conditions.

[0079] The specific linear positive adjustment formula is as follows: Where γ is the high-frequency weight adjustment coefficient, and in this embodiment, γ = 0.6 is used to control the weight correction amplitude; based on the weight normalization constraint, the electrical attenuation weight synchronously and adaptively adapts: This adjustment method ensures that the more significant the high-frequency offset, the more the system focuses on evaluating the waveform attenuation dimension, thus adapting to the degradation patterns of high-frequency communication loops. If ≤ If the non-high-frequency offset condition is determined, there is no need to perform high-frequency weight correction. The system is reset and the initial weight remains unchanged.

[0080] The system executes low-frequency operating condition weighted adaptive adjustment logic: when the calculated frequency ratio <Second Reference Ratio When the interface under test is in a low-frequency communication condition, it is determined that the current interface is in a low-frequency communication condition. During low-frequency signal transmission, high-frequency signal distortion is negligible, and the steady-state voltage and current amplitude loss caused by line impedance is the core degradation characteristic, making the evaluation value of electrical attenuation indicators higher. This application follows the adjustment rule that the frequency ratio and electrical attenuation weight are linearly positively correlated, that is, the smaller the frequency ratio and the lower the operating frequency, the greater the electrical attenuation weight, which is suitable for the transmission characteristics dominated by electrical loss in low-frequency operating conditions.

[0081] The specific linear positive adjustment formula is as follows: Where η is the low-frequency weight adjustment coefficient, and in this embodiment, η = 0.6 is used to ensure a balanced and uniform weight correction amplitude; based on the weight normalization constraint, the waveform attenuation weight is synchronously and adaptively adapted. This adjustment method ensures that the more significant the low-frequency offset, the more the system focuses on the evaluation results of the electrical attenuation dimension, which aligns with the degradation mechanism of steady-state loss in low-frequency communication circuits. If ≥ If the non-low-frequency offset condition is determined, there is no need to perform low-frequency weight correction. The system is reset and the initial weight remains unchanged.

[0082] For the intermediate frequency standard range, i.e. ≤ ≤ The system determines that the current communication frequency is within the rated allowable range, and the impact of waveform loss and electrical loss on line performance is balanced. No adaptive weight correction is required. The weights are directly reset and initialized to participate in the calculation, ensuring that the evaluation benchmark is consistent and the judgment result is stable under standard operating conditions.

[0083] This scheme follows the threshold-level constraint logic. Regardless of whether high-frequency or low-frequency adaptive adjustment is triggered, it always ensures that the first reference ratio is always greater than the second reference ratio. The frequency partitions are free from overlap, intersection, and disorder, ensuring that the weight adjustment logic is executed in an orderly, hierarchical, and stable manner.

[0084] After completing the adaptive weight configuration, the system calculates the final actual attenuation value ΔK using a standardized weighted fusion formula. The specific calculation formula is as follows: Wherein, ΔK is the electrical attenuation value calculated above, and ΔK is the waveform attenuation value calculated above. , These are the real-time effective weights after adaptive adjustment or initialization reset, and they always satisfy the normalization condition.

[0085] In the actual operation of the communication transmission loop of the converter station, in addition to the communication master frequency changing the dominant dimension of signal attenuation, the volume of data transmitted by the communication service can equivalently characterize the effective continuous communication duration and the degree of long-term operating load accumulation, which are operating condition parameters affecting the benchmark for judging line degradation. In the aforementioned frequency adaptive weight adjustment mechanism, the first reference ratio and the second reference ratio used to divide the high-frequency, medium-frequency, and low-frequency operating conditions are fixed benchmark thresholds, which only adapt to the rated operating conditions of standard data throughput. However, in actual engineering scenarios, large data volumes and long-term continuous communication will lead to cable heat accumulation, slight changes in interface contact resistance, and increased steady-state losses of the line, passively increasing the proportion of electrical attenuation's impact on line performance; under small data volumes and short-term intermittent communication conditions, the line has no obvious heat accumulation loss, and subtle waveform distortion defects are more easily exposed. Therefore, fixed thresholds cannot adapt to the differentiated detection requirements of different communication durations and different load volumes. This embodiment discloses a frequency partitioning threshold adaptive correction method based on communication data volume, which dynamically corrects the frequency judgment threshold by the data volume ratio, realizing the judgment interval adaptively shifting with the operating load, further improving the attenuation quantification accuracy across all scenarios. The specific steps are as follows: During the testing process, the communication data volume D of the interface under test is acquired in real time. This communication data volume represents the total amount of service data effectively transmitted by the interface within the current testing cycle. It can be used to characterize the continuous communication duration and operating load intensity of the line. The larger the communication data volume, the longer the line can withstand continuous pressure and the more significant the heat accumulation loss. The system has a pre-stored standard set data volume. The set data volume is the standard communication data volume per unit cycle calibrated under the rated standard operating conditions of the converter station, serving as a unified benchmark for threshold correction. The system quantifies the load deviation of the current operating condition relative to the standard operating condition through ratio calculation, and calculates the dimensionless data volume ratio. The calculation formula is: .in, >1 represents heavy-load, long-duration communication conditions. =1 represents the standard rated operating condition. <1 represents a light-load, short-term communication condition.

[0086] The system has a pre-set hierarchical control threshold, which is the first control ratio. Ratio to the second control And strictly satisfy the hierarchical constraints: > This embodiment has been calibrated through field testing, and the preferred settings are... =1.1、 =0.9, based on which the communication data volume operating conditions are divided into high load range, standard load range and low load range, to realize the interval threshold correction and adapt to the line degradation judgment requirements of different communication durations.

[0087] When the data volume ratio Greater than the first control ratio ,Right now When the ratio is greater than 1.1, the interface under test is determined to be under high load conditions with large data volume and long-term continuous communication. The heat accumulation effect of the line is significant, and the weight of electrical steady-state loss on the line transmission performance is greatly increased, requiring adaptive widening of the low-frequency electrical evaluation range. This application follows the adjustment rule that the data volume ratio and the second reference ratio are linearly positively correlated. That is, the larger the data volume ratio, the higher the load intensity, and the longer the communication duration, the larger the corrected second reference ratio, and the lower the low-frequency judgment range is correspondingly widened to adapt to the degradation characteristics dominated by electrical loss under heavy load conditions.

[0088] The specific positive linear adjustment formula is as follows: .in, This is the corrected real-time second reference ratio. The initial baseline value for the second reference ratio is 0.8, which is fixed in this embodiment; μ is the positive adjustment coefficient for data volume, with a value of 0.6, used to control the threshold correction amplitude and ensure adjustment linearity and stability. A larger data volume ratio results in a larger correction increment, a higher second reference ratio, and a wider low-frequency electrical weight evaluation range, matching the line loss patterns of long-term communication and large-volume data transmission. ≤ When a non-high load condition is determined, no correction of the low-frequency threshold is required, and the system initializes and resets the second reference ratio to the baseline value. .

[0089] When the data volume ratio Less than the second control ratio ,Right now When the ratio is less than 0.9, the interface under test is determined to be in a low-load condition with small data volume and short-intermittent communication. There is no significant heat accumulation loss in the line, and the impact of electrical steady-state loss is negligible. High-frequency waveform distortion and minute energy loss become the main indicators of line degradation, requiring adaptive expansion of the high-frequency waveform evaluation range. This application follows the adjustment rule that the data volume ratio and the first reference ratio are linearly positively correlated; that is, the smaller the data volume ratio, the smaller the first reference ratio; and the larger the data volume ratio, the larger the first reference ratio.

[0090] The specific positive linear adjustment formula is as follows: .in, This is the corrected real-time first reference ratio. The initial reference value for the first reference ratio is 1.2, which is fixed in this embodiment; σ is the low-load positive adjustment coefficient, with a value of 0.6, consistent with the aforementioned adjustment coefficient. < Within the interval, The smaller, ( - The smaller the calculation result, the smaller the corrected first reference ratio, effectively widening the high-frequency waveform weight evaluation range and adapting to the waveform degradation characteristics of light-load, short-time communication conditions. ≥ When a non-low load condition is determined, no correction of the high-frequency threshold is required, and the system initializes and resets the first reference ratio to the baseline value. .

[0091] For the standard load range, i.e. ≤ ≤ That is, 0.9≤ If the current communication data volume and communication duration are within the standard rated range, the line has no obvious thermal accumulation deviation, and the operating conditions are consistent with the initial calibration reference operating conditions, the system will turn off all threshold adaptive correction logic, initialize and reset the first reference ratio and the second reference ratio, and ensure that the frequency partition judgment reference is unified, stable and without offset under the standard operating conditions.

[0092] This embodiment uses mandatory hierarchical constraint logic throughout the process. Regardless of whether high-load or low-load threshold corrections are triggered, it always ensures that the adjusted real-time first reference ratio is always greater than the adjusted real-time second reference ratio. > This ensures that the high-frequency judgment interval, mid-frequency equalization interval, and low-frequency judgment interval remain independently layered, without overlap, intersection, or disorder, thus guaranteeing the orderly and stable operation of the aforementioned frequency adaptive weight adjustment logic. In this embodiment, all threshold or parameter settings were obtained from statistical analysis of measured data from over 100 interfaces of the converter station, and the coefficients were optimized through orthogonal experiments.

[0093] This application also discloses a simulation testing device for a converter station communication transmission loop, including a processor, wherein the processor executes the steps of the simulation testing method for the converter station communication transmission loop as described in any of the above embodiments.

[0094] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A simulation detection method for a converter station communication transmission loop, characterized in that, Based on at least one communication test interface for connecting to the interface under test, the method includes: setting up a multi-stage positive switch and a multi-stage negative switch at the communication test interface; setting up an inductor regulator and a capacitor regulator in series between the multi-stage positive switch and the multi-stage negative switch; and connecting a terminating analog resistor in parallel with the capacitor regulator; acquiring a first test set and a second test set of the same type; setting up the inductor regulator, capacitor regulator and terminating analog resistor according to the first test set; connecting the interface under test to the communication test interface; acquiring first electrical data and first waveform data of the terminating analog resistor; obtaining second electrical data and second waveform data based on the second test set; calculating an electrical attenuation value based on the first electrical data and the second electrical data; calculating a waveform attenuation value based on the first waveform data and the second waveform data; calculating an actual attenuation value based on the electrical attenuation value and the waveform attenuation value; matching a target attenuation value from a preset attenuation database according to the first test set and the second test set; and issuing a line abnormality prompt if the actual attenuation value > the target attenuation value.

2. The simulation detection method for the communication transmission loop of a converter station according to claim 1, characterized in that, The inductor regulator includes a housing, which is filled with a magnetic fluid liquid. The magnetic fluid liquid is a paramagnetic iron oxide particle magnetic fluid. A single-wire spiral wire immersed in the magnetic fluid liquid passes through the housing. A temperature sensor, a semiconductor cooling chip, two end point heat-conducting plates, and a switching drive are disposed on the housing. The system acquires the actual temperature generated by the temperature sensor and the target temperature of the inductor regulator. It calculates the ratio between the actual temperature and the target temperature as the temperature ratio, and calculates the absolute value of the difference between the temperature ratio and the preset temperature reference value as the temperature control value. If the temperature control value is greater than the preset basic control value, the temperature control mode is entered and the driver is enabled; otherwise, the temperature control mode is exited and the driver is reset. In the reset state, the driver drives the heat-conducting plates at both ends to not contact the semiconductor cooling plate. The cooling power of the thermoelectric cooler is adjusted according to the temperature control value. If the temperature ratio is greater than the preset temperature reference value, the control switching drive will switch the heat-conducting plates at both ends to the cooling contact surface of the thermoelectric cooler; otherwise, the control switching drive will switch the heat-conducting plates at both ends to the heat-conducting contact surface of the thermoelectric cooler.

3. The simulation detection method for the communication transmission loop of a converter station according to claim 1, characterized in that, The inductor regulator includes multiple series-connected helical wires and an adjustment slider that short-circuits the helical wires; Obtain the first test set or the second test set, extract inductance data from the first test set or the second test set, obtain the basic inductance data corresponding to the spiral wire, and calculate the total inductance data based on the basic inductance data and the number of spiral wires; The inductance difference is calculated from the total inductance data and the difference between the inductance data. The ratio of the inductance difference to the total inductance data is used as the inductance adjustment value. The distance of the adjustment slider from the initial position on multiple spiral wires is controlled according to the positive correlation of the inductance adjustment value. When the adjustment slider is at the initial position, the inductance value of the inductance regulator is the total inductance data.

4. The simulation detection method for the communication transmission loop of a converter station according to claim 1, characterized in that, The capacitor regulator includes multiple capacitor banks connected in parallel via a bank switching switch. The multiple capacitor banks have the same structure. Each capacitor bank has multiple capacitors connected in parallel via a sub-switching switch. The capacitance values ​​of the capacitors in the bank are different. Obtain either the first test set or the second test set, extract capacitance data from the first test set or the second test set, and obtain the capacitance value corresponding to the capacitor. The capacitance value of a single capacitor bank is calculated based on the capacitance value corresponding to the capacitor bank; The number of capacitor groups is calculated based on the capacitance data and capacitor group data. The product of the capacitor group data and the group data is less than the capacitance data and less than (capacitor group data + 1) and the product of the group data. The capacitor group corresponding to the group data is used as the supplementary capacitor group. The difference between the capacitance data and the product of the capacitor group data is used as the remaining capacitance data. The corresponding capacitor is matched in the capacitor group based on the remaining capacitance data as the supplementary capacitor. Turn on the group switching switch corresponding to the supplementary capacitor group and the sub-switching switch corresponding to the supplementary capacitor.

5. The simulation detection method for the communication transmission loop of a converter station according to claim 2, characterized in that, The capacitor regulator includes two capacitor electrode plates facing each other and a drive unit that drives one of the capacitor electrode plates to slide, and the drive unit changes the distance between the two capacitor electrode plates after it is activated. Obtain either the first test set or the second test set, extract capacitance data from the first test set or the second test set, and obtain the data corresponding to the capacitance distance to the capacitor electrode plate. The driving distance is calculated based on the capacitance data and the corresponding capacitance distance data, and the driving position of the driving component is controlled based on the positive correlation of the driving distance.

6. The simulation detection method for the communication transmission loop of a converter station according to claim 1, characterized in that, The step of calculating the electrical attenuation value based on the first electrical data and the second electrical data also includes the following sub-steps: The first electrical data includes multiple first voltage data and multiple first current data that correspond one-to-one. The average value of the multiple first voltage data is calculated as the first voltage value, and the average value of the multiple first current data is calculated as the first current value. The second electrical data includes multiple corresponding second voltage data and multiple second current data. The average value of the multiple second voltage data is calculated as the second voltage value, and the average value of the multiple second current data is calculated as the second current value. The ratio of the first voltage value to the second voltage value is calculated as the voltage ratio, and the ratio of the first current value to the second current value is calculated as the current ratio. The overall ratio is calculated by weighting the voltage ratio and the current ratio, and the difference between the overall ratio and the preset first set ratio is used as the electrical attenuation value.

7. The simulation detection method for the communication transmission loop of a converter station according to claim 6, characterized in that, The step of calculating the waveform attenuation value based on the first waveform data and the second waveform data also includes the following sub-steps: Within a preset attenuation time period, first communication data is extracted based on the first waveform data using a preset extraction algorithm, and second communication data is extracted based on the second waveform data using the extraction algorithm. If the first communication data is consistent with the second communication data, the area enclosed by the first waveform data and the coordinate system is calculated as the first area, the area enclosed by the second waveform data and the coordinate system is calculated as the second area, the ratio of the first area and the second area is calculated as the area ratio, and the difference between the area ratio and the preset second set ratio is calculated as the waveform attenuation value. Otherwise, set the waveform attenuation value to the preset maximum waveform attenuation value.

8. The simulation detection method for the communication transmission loop of a converter station according to claim 7, characterized in that, The steps for calculating the actual attenuation value based on the electrical attenuation value and the waveform attenuation value also include the following steps: The electrical attenuation value and the waveform attenuation value are weighted by the initialized weights to calculate the actual attenuation value; Obtain the communication frequency of the interface to be tested, and calculate the ratio between the communication frequency and the preset setting frequency as the frequency ratio. If the frequency ratio is greater than the preset first reference ratio, the weight of the waveform attenuation value is adjusted according to the positive correlation of the frequency ratio. Otherwise, initialize the weights; If the frequency ratio is less than the preset second reference ratio, the weight of the electrical attenuation value is adjusted according to the positive correlation of the frequency ratio. Otherwise, initialize the weights; The first reference ratio is greater than the second reference ratio.

9. The simulation detection method for the communication transmission loop of a converter station according to claim 8, characterized in that, The method also includes the following steps: Obtain the communication data volume of the interface to be tested, and calculate the ratio between the communication data volume and the preset data volume as the data volume ratio; If the data volume ratio is greater than the preset first reference ratio, the second reference ratio will be adjusted according to the positive correlation between the data volume ratio and the reference ratio. Otherwise, initialize the second reference ratio; If the data volume ratio is less than the preset second control ratio, the first reference ratio is adjusted according to the positive correlation of the data volume ratio. Otherwise, initialize the first reference ratio; Among them, the first control ratio is greater than the second control ratio, and the adjusted first reference ratio is greater than the adjusted second reference ratio.

10. A simulation testing device for a converter station communication transmission loop, characterized in that, Includes a processor, wherein the processor performs the steps of the simulation detection method for the converter station communication transmission loop as described in any one of claims 1-9.

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