An intelligent control method and system for a power frequency series resonance device

Abstract

The present invention relates to the technical field of resonance test equipment, in particular to an intelligent control method and system for a power frequency series resonance device. Historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested is obtained, and the mutation probability of the voltage mutation point generated during the series circuit resonance test is calculated according to the historical partial discharge test data; if the topological node with a mutation probability greater than the preset mutation probability is not in the topological node area where the voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, the frequency drift generated when the frequency signal is adjusted to the adjusted frequency strategy is calibrated; if it is in, the gain control of the feedback network for the operational amplifier is calibrated according to the gain difference between the actual resonance point distribution diagram and the accurate resonance point distribution diagram, and the calibrated negative feedback network is optimized twice. The present invention can perform intelligent control on the power frequency series resonance device during the withstand voltage test, thereby ensuring the stability of the resonance state.

Description

Technical Field

[0001] The present invention relates to the technical field of resonance test equipment, and particularly to an intelligent control method and system for a power frequency series resonance device. Background Art

[0002] A power frequency series resonance device refers to a device that generates a resonance phenomenon in a circuit by adjusting circuit parameters and using appropriate power electronic devices under alternating current power frequency. In the power system, power frequency series resonance devices are usually used to test the insulation performance of high-voltage power equipment, such as transformers, cables, circuit breakers, etc. The power frequency series resonance device can simulate the voltage waveform under actual operating conditions to detect the partial discharge of the device and the insulation performance under overvoltage, and more accurately evaluate the insulation performance of the device. However, due to the long-term operation and performance degradation of the series resonance circuit and control system of the power frequency series resonance device, the accuracy of controlling the power frequency series resonance device has been greatly reduced, resulting in an increase in the bandwidth and poor frequency response when the power frequency series resonance device identifies the resonance point, causing situations such as omission and misidentification of the resonance point, making it difficult to maintain a stable resonance state, and ultimately causing sudden changes such as interruption or attenuation of the voltage during the withstand voltage test, reducing the accuracy of the withstand voltage test results, and easily leading to the occurrence of high-voltage test safety accidents, which is not conducive to the stable operation of the power frequency series resonance device. Summary of the Invention

[0003] The present invention overcomes the deficiencies of the prior art and provides an intelligent control method and system for a power frequency series resonance device.

[0004] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0005] The first aspect of the present invention provides an intelligent control method for a power frequency series resonance device, including the following steps:

[0006] Obtain the historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested, analyze the historical partial discharge test data to construct an output voltage topology diagram of the series resonance circuit, calculate the transition probability matrix of the historical voltage mutation points generated during the test of the series resonance circuit according to the output voltage topology diagram of the series resonance circuit, and obtain the mutation probability of the historical voltage mutation points in the output voltage topology diagram of the series resonance circuit;

[0007] If the abnormal control topology nodes of the series resonance circuit with a mutation probability greater than the preset mutation probability are not in the historical topology node area where the historical voltage mutation points are located in the output voltage topology diagram of the series resonance circuit, obtain the frequency signal of the resonance frequency point, and calibrate the frequency drift generated when the frequency adjustment strategy is adjusted to the frequency signal to obtain the first intelligent control scheme;

[0008] If the abnormal control topology node of the series resonant circuit with a mutation probability greater than the preset mutation probability is in the historical topological node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonant circuit, then calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonance point distribution diagram and the accurate resonance point distribution diagram, and perform secondary optimization on the calibrated negative feedback network to obtain a second intelligent control scheme;

[0009] After running the first intelligent control scheme or the second intelligent control scheme, obtain the actual partial discharge test data of the power equipment to be tested, construct a tree-shaped discharge dynamic model according to the actual partial discharge test data, predict and analyze the partial discharge amplitude based on the tree-shaped discharge dynamic model, generate an early warning signal and an instantaneous protection control signal to cut off the circuit, so as to improve the safety of the withstand voltage test of the power frequency series resonance device.

[0010] Further, in a preferred embodiment of the present invention, the method for obtaining the historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested, analyzing the historical partial discharge test data to construct an output voltage topology diagram of the series resonant circuit, and calculating the transition probability matrix of the historical voltage mutation point generated during the test of the series resonant circuit according to the output voltage topology diagram of the series resonant circuit to obtain the mutation probability of the historical voltage mutation point in the output voltage topology diagram of the series resonant circuit specifically includes the following steps:

[0011] Obtain the power equipment to be tested of the power frequency series resonance device and the test log, and retrieve the historical partial discharge test data of the power equipment to be tested through the test log;

[0012] Construct a cumulative distribution partial discharge map according to the historical partial discharge test data, and strip the historical output voltage adjustment map of the power equipment to be tested based on the cumulative distribution partial discharge map;

[0013] Obtain the initialization parameter configuration when the power frequency series resonance device generates the historical output voltage adjustment map, extract the normal output voltage waveform of the power equipment to be tested through the initialization parameter configuration, and preset the allowable adjustment fluctuation range of the output voltage according to the normal output voltage waveform;

[0014] Taking the allowable adjustment fluctuation range as a reference, calibrate the output voltage adjustment value outside the allowable adjustment fluctuation range as a historical voltage mutation point. If there is at least one or more historical voltage mutation points in the historical output voltage adjustment map, calculate the topological historical output voltage adjustment map according to Kirchhoff's law to obtain the output voltage topology diagram of the series resonant circuit of the power frequency series resonance device;

[0015] Obtain the voltage distribution input nodes of the output voltage topology diagram of the series resonance circuit, mark the historical topological node areas where the historical voltage mutation points are located in the output voltage topology diagram of the series resonance circuit, and obtain the voltage distribution of the historical topological node areas. Preset the restart probability according to the voltage distribution of the historical topological node areas;

[0016] Taking the voltage distribution input nodes as the initial nodes, calculate the probability vector of the initial nodes transferring to the historical topological node areas through the restart probability, obtain the transition probability matrix of the output voltage topology diagram of the series resonance circuit, and repeat the above steps to continuously update and iterate the transition probability matrix;

[0017] Preset the iteration frequency. When the update iteration reaches the iteration frequency, perform convergence processing to generate the final transition probability matrix of the output voltage topology diagram of the series resonance circuit, and obtain the mutation probability of the historical voltage mutation point in the output voltage topology diagram of the series resonance circuit according to the final transition probability matrix.

[0018] Further, in a preferred embodiment of the present invention, if the abnormal control topological nodes of the series resonance circuit with a mutation probability greater than the preset mutation probability are not in the historical topological node areas where the historical voltage mutation points are located in the output voltage topology diagram of the series resonance circuit, then obtain the frequency signal of the resonance frequency point, and calibrate the frequency drift generated when adjusting the frequency strategy to the frequency signal to obtain the first intelligent control scheme, which specifically includes the following steps:

[0019] Mark the topological nodes with a mutation probability greater than the preset mutation probability in the output voltage topology diagram of the series resonance circuit of the power frequency series resonance device, and define them as the abnormal control topological nodes of the series resonance circuit. Judge whether the abnormal control topological nodes of the series resonance circuit are in the historical topological node areas where the historical voltage mutation points are located in the output voltage topology diagram of the series resonance circuit;

[0020] If it is not in the historical topological node areas where the historical voltage mutation points are located in the output voltage topology diagram of the series resonance circuit, then extract the preset frequency step and the preset frequency range of the power frequency series resonance device for the power equipment to be tested through the initialization parameter configuration;

[0021] Obtain the voltage-current curve diagram scanned by the frequency scanning technology according to the preset frequency step in the preset frequency range, and mark the frequency points with the largest current value and the smallest voltage value according to the voltage-current curve diagram to obtain multiple resonance frequency points;

[0022] Obtain the current distribution and voltage distribution of each resonance frequency point in the output voltage topology diagram of the series resonance circuit, preset the search range of each resonance frequency point based on the current distribution and voltage distribution, and draw the frequency signals of each resonance frequency point;

[0023] Obtain the communication protocol and control technology of the power frequency series resonance device, determine the frequency adjustment mechanism of the power frequency series resonance device according to the communication protocol and control technology, and retrieve the frequency adjustment strategy of the frequency adjustment mechanism for the power frequency series resonance device;

[0024] Extract the adjusted frequency signal finally generated when adjusting the input voltage of the variable frequency power supply to the frequency signals of each resonance frequency point through the frequency adjustment strategy, and at this time, determine whether the adjusted frequency signal is within the search range corresponding to each resonance frequency point;

[0025] If not, perform Hilbert transform on the adjusted frequency signal that is not within the search range of the resonance frequency point and the corresponding frequency signal to obtain the envelope arctangent value of the adjusted frequency signal and the envelope arctangent value of the frequency signal, calculate the phase difference between the envelope arctangent value of the adjusted frequency signal and the envelope arctangent value of the frequency signal, and obtain the instantaneous phase difference;

[0026] Preset an unpacking phase interval, expand the instantaneous phase difference in the unpacking phase interval to solve the time derivative of the instantaneous phase difference, calculate the frequency offset according to the time derivative, and obtain the frequency drift amount of the adjusted frequency signal;

[0027] Based on the frequency drift amount, re-tune the frequency adjustment strategy of the frequency adjustment mechanism for the power frequency series resonance device to obtain the first intelligent control scheme.

[0028] Further, in a preferred embodiment of the present invention, if the abnormal control topology node of the series resonance circuit with a mutation probability greater than the preset mutation probability is in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, then calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonance point distribution diagram and the accurate resonance point distribution diagram, and perform secondary optimization on the calibrated negative feedback network to obtain the second intelligent control scheme, which specifically includes the following steps:

[0029] If the abnormal control topology node of the series resonance circuit is within the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, then obtain the preset frequency step and preset frequency range of the power frequency series resonance device for the power equipment to be tested through initial parameter configuration;

[0030] Obtain the layout information of all operational amplifiers set in the series resonance circuit by the power frequency series resonance device, divide the preset frequency range into several sub-frequency ranges based on the layout information, and perform precise step scanning on each sub-frequency range based on the preset frequency step to obtain the accurate resonance point distribution diagram;

[0031] Obtain the actual resonance point distribution maps corresponding to each sub - frequency range when the power - frequency series resonance device generates the historical output voltage regulation map. Taking the accurate resonance point distribution map as a reference benchmark, plan the frequency ranges where accurate resonance points are missing in the actual resonance point distribution maps of each sub - frequency range, and define them as low - frequency response regions;

[0032] Obtain the negative - feedback network of the operational amplifier. At the same time, obtain the actual gain adjustment values of the negative - feedback network in each low - frequency response region, calculate the deviation between each actual gain adjustment value and the accurate gain adjustment value to obtain the gain deviation, and determine the quality factor for the negative - feedback network to control the bandwidth of the series resonance circuit according to the gain deviation;

[0033] Preset an ideal quality factor, calibrate and initialize the gain control of the feedback network for the operational amplifier according to the quality factor until the quality factor approaches the ideal quality factor, and obtain the calibrated negative - feedback network;

[0034] Precisely control the power - frequency series resonance device by outputting new inductance reactance parameters and new capacitance reactance parameters through the calibrated negative - feedback network. If there are still missing accurate resonance points in the resonance point distribution map after calibration scanning, then construct an adjusted feedback - loop compensation network to improve the control accuracy of the operational amplifier, and obtain the second intelligent control scheme.

[0035] Further, in a preferred embodiment of the present invention, the step of precisely controlling the power - frequency series resonance device by outputting new inductance reactance parameters and new capacitance reactance parameters through the calibrated negative - feedback network, and if there are still missing accurate resonance points in the resonance point distribution map after calibration scanning, then constructing an adjusted feedback - loop compensation network to improve the control accuracy of the operational amplifier to obtain the second intelligent control scheme specifically includes the following steps:

[0036] Precisely control the power - frequency series resonance device to rescan the preset frequency range by outputting new inductance reactance parameters and new capacitance reactance parameters through the calibrated negative - feedback network, and obtain the resonance point distribution map after calibration scanning;

[0037] If there are still missing accurate resonance points in the resonance point distribution map after calibration scanning compared with the accurate resonance point distribution map, then obtain the model specifications of each operational amplifier used to control the series resonance circuit, and retrieve the preset gain - bandwidth product of each operational amplifier based on the model specifications in the big - data network;

[0038] Obtain the accurate resonance points at the current peak and voltage peak in the accurate resonance point distribution map, define them as peak resonance points, extract the target frequency response values of the negative - feedback network of the operational amplifier in response to the peak resonance points, and determine the preset feedback coefficient of the feedback - loop compensation network according to the target frequency response values and the preset gain - bandwidth product;

[0039] Introduce the pole analysis algorithm to analyze the change of the pole position of the series resonance circuit in the power frequency series resonance device when scanning the preset frequency range, so as to determine the change of the pole position of the series resonance circuit under the change of the scanning frequency range and the corresponding phase margin, and calculate the actual frequency response value of the series resonance circuit scanning the peak resonance point in the power frequency series resonance device according to the change of the pole position and the corresponding phase margin;

[0040] Obtain the series resonance knowledge graph based on the big data network, import the model specifications of the operational amplifier into the series resonance knowledge graph for identification, determine the feedback loop compensation network architecture, and initialize the feedback loop compensation network architecture through the preset feedback coefficient;

[0041] Adjust the phase delay between the actual frequency response value and the target frequency response value in the initialized feedback loop compensation network architecture until the feedback coefficient in the output voltage topology diagram of the series resonance circuit reaches the preset feedback coefficient, and obtain the adjusted feedback loop compensation network;

[0042] Upload the adjusted feedback loop compensation network to the series resonance circuit control terminal of the power frequency series resonance device to improve the frequency response performance of the amplifier adjusting the inductor and capacitor to scan different frequency ranges, and obtain the second intelligent control scheme.

[0043] Further, in a preferred embodiment of the present invention, after running the first intelligent control scheme or the second intelligent control scheme, obtain the actual partial discharge test data of the power equipment to be tested, construct a tree-shaped discharge dynamic model according to the actual partial discharge test data, predict and analyze the partial discharge amplitude based on the tree-shaped discharge dynamic model, generate a warning signal and an instantaneous protection control signal to cut off the circuit, so as to improve the safety of the withstand voltage test of the power frequency series resonance device, which specifically includes the following steps:

[0044] Conduct an actual test on the power equipment to be tested through the power frequency series resonance device, run the first intelligent control scheme or the second intelligent control scheme during the test process to adjust the resonance steady state of the power frequency series resonance device and record the test data, and obtain the actual partial discharge test data of the power equipment to be tested;

[0045] Preset several uniform time sequence test intervals, extract the actual partial discharge test data corresponding to each uniform time sequence test interval from the actual partial discharge test data, and define it as a sub-test data group;

[0046] Obtain the discharge signal intensity and discharge signal distribution applied by the power frequency series resonance device to the power equipment under test at each uniform time sequence test interval according to several groups of sub-test data groups, and perform model fitting based on the discharge signal intensity and discharge signal distribution to construct an electrical tree effect time sequence discharge model corresponding to each group of sub-test data groups;

[0047] Introduce the LSTM algorithm to perform time sequence dynamic calculation on the electrical tree effect time sequence discharge model corresponding to each group of sub-test data groups and construct a model to generate a tree-shaped discharge dynamic model;

[0048] Preset a future time sequence test interval, and predict the discharge state trend of the future time sequence test interval through the tree-shaped discharge dynamic model to determine the actual partial discharge amplitude of the power frequency series resonance device for the power equipment under test at the future time sequence test interval;

[0049] Obtain the historical withstand voltage evaluation information of the power equipment under test, preset the breakdown critical value of the partial discharge test according to the historical withstand voltage evaluation information, and at the same time obtain the lowest partial discharge amplitude required to reach the breakdown critical value, and judge whether the actual partial discharge amplitude exceeds the lowest partial discharge amplitude;

[0050] If it exceeds, control the warning mechanism of the power frequency series resonance device to send out an alarm signal. At this time, calculate the difference between the actual partial discharge amplitude and the lowest partial discharge amplitude to obtain the amplitude deviation rate;

[0051] When the amplitude deviation rate is greater than the preset amplitude deviation rate, generate an instantaneous protection control signal based on the amplitude deviation rate, and immediately cut off the power supply operation of the power frequency series resonance device through the instantaneous protection control signal when a breakdown phenomenon occurs, so as to improve the safety factor during the withstand voltage test of the power frequency series resonance device.

[0052] The second aspect of the present invention provides an intelligent control system for a power frequency series resonance device. The intelligent control system for a power frequency series resonance device includes a memory and a processor. A program for an intelligent control method of a power frequency series resonance device is stored in the memory. When the program for an intelligent control method of a power frequency series resonance device is executed by the processor, the following steps are implemented:

[0053] Obtain the historical partial discharge test data of the power frequency series resonance device for the power equipment under test, analyze the historical partial discharge test data to construct an output voltage topology diagram of the series resonance circuit, and calculate the transition probability matrix of the historical voltage mutation point generated during the test of the series resonance circuit according to the output voltage topology diagram of the series resonance circuit to obtain the mutation probability of the historical voltage mutation point in the output voltage topology diagram of the series resonance circuit;

[0054] If the abnormal control topology node of the series resonant circuit with a mutation probability greater than the preset mutation probability is not in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonant circuit, obtain the frequency signal of the resonant frequency point, and calibrate the frequency drift generated when the frequency adjustment strategy is adjusted to the frequency signal to obtain the first intelligent control scheme;

[0055] If the abnormal control topology node of the series resonant circuit with a mutation probability greater than the preset mutation probability is in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonant circuit, calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonant point distribution diagram and the accurate resonant point distribution diagram, and perform secondary optimization on the calibrated negative feedback network to obtain the second intelligent control scheme;

[0056] After running the first intelligent control scheme or the second intelligent control scheme, obtain the actual partial discharge test data of the power equipment to be tested, construct a tree-shaped discharge dynamic model according to the actual partial discharge test data, predict and analyze the partial discharge amplitude based on the tree-shaped discharge dynamic model, and generate an early warning signal and an instantaneous protection control signal to cut off the circuit, so as to improve the safety of the withstand voltage test of the power frequency series resonance device.

[0057] The present invention solves the technical defects existing in the background art, and the beneficial technical effects of the present invention are as follows:

[0058] Obtain the historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested, calculate the transition probability matrix of the voltage mutation point generated during the resonance test of the series resonant circuit according to the historical partial discharge test data, and obtain the mutation probability of the voltage mutation point in the output voltage topology diagram of the series resonant circuit; if the topology node with a mutation probability greater than the preset mutation probability is not in the topology node area where the voltage mutation point is located in the output voltage topology diagram of the series resonant circuit, calibrate the frequency drift generated when the frequency adjustment strategy is adjusted to the frequency signal; if it is in the topology node area where the voltage mutation point is located in the output voltage topology diagram of the series resonant circuit, calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonant point distribution diagram and the accurate resonant point distribution diagram, and perform secondary optimization on the calibrated negative feedback network; construct a tree-shaped discharge dynamic model according to the actual partial discharge test data, predict and analyze the partial discharge amplitude based on the tree-shaped discharge dynamic model, and generate an early warning signal and an instantaneous protection control signal to cut off the circuit. The present invention can perform intelligent control on the power frequency series resonance device during the withstand voltage test, thereby ensuring the stability of the resonance state and improving the safety factor of the withstand voltage test. Description of the Drawings

[0059] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0060] Figure 1 Shows a first method flow chart of an intelligent control method for a power frequency series resonance device;

[0061] Figure 2 Shows a second method flow chart of an intelligent control method for a power frequency series resonance device;

[0062] Figure 3 Shows a third method flow chart of an intelligent control method for a power frequency series resonance device;

[0063] Figure 4 Shows a system framework diagram of an intelligent control system for a power frequency series resonance device. Detailed implementation manners

[0064] In order to more clearly understand the above objects, features, and advantages of the present invention, the present invention will be further described in detail below in conjunction with the drawings and specific implementation manners. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0065] Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0066] The first aspect of the present invention provides an intelligent control method for a power frequency series resonance device, as Figure 1 shown, including the following steps:

[0067] S102: Obtain historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested, analyze the historical partial discharge test data to construct an output voltage topology diagram of the series resonance circuit, calculate a transition probability matrix of historical voltage mutation points during the test of the series resonance circuit according to the output voltage topology diagram of the series resonance circuit, and obtain the mutation probability of the historical voltage mutation points in the output voltage topology diagram of the series resonance circuit;

[0068] S104: If the abnormal control topology node of the series resonance circuit with a mutation probability greater than the preset mutation probability is not in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, obtain the frequency signal of the resonance frequency point, calibrate the frequency drift generated when adjusting the frequency strategy to the frequency signal, and obtain the first intelligent control scheme;

[0069] S106: If the abnormal control topology node of the series resonance circuit with a mutation probability greater than the preset mutation probability is in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonance point distribution diagram and the accurate resonance point distribution diagram, and perform secondary optimization on the calibrated negative feedback network to obtain the second intelligent control scheme;

[0070] S108: After running the first intelligent control scheme or the second intelligent control scheme, obtain the actual partial discharge test data of the power equipment to be tested, construct a tree-shaped discharge dynamic model according to the actual partial discharge test data, predict and analyze the partial discharge amplitude based on the tree-shaped discharge dynamic model, generate an early warning signal and an instantaneous protection control signal to cut off the circuit, so as to improve the safety of the withstand voltage test of the power frequency series resonance device.

[0071] Further, in a preferred embodiment of the present invention, the method for obtaining the historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested, analyzing the historical partial discharge test data to construct an output voltage topology diagram of the series resonance circuit, and calculating the transition probability matrix of the historical voltage mutation point generated during the test of the series resonance circuit according to the output voltage topology diagram of the series resonance circuit to obtain the mutation probability of the historical voltage mutation point in the output voltage topology diagram of the series resonance circuit specifically includes the following steps:

[0072] Obtain the power equipment to be tested of the power frequency series resonance device and the test log, and retrieve the historical partial discharge test data of the power equipment to be tested through the test log;

[0073] Construct a cumulative distribution partial discharge map according to the historical partial discharge test data, and strip the historical output voltage adjustment map of the power equipment to be tested based on the cumulative distribution partial discharge map;

[0074] Obtain the initial parameter configuration when the power frequency series resonance device generates the historical output voltage adjustment map, extract the normal output voltage waveform of the power equipment to be tested through the initial parameter configuration, and preset the allowable adjustment fluctuation range of the output voltage according to the normal output voltage waveform;

[0075] Based on the allowable adjustment fluctuation range, the output voltage adjustment value outside the allowable adjustment fluctuation range is calibrated as a historical voltage mutation point. If there is at least one or more historical voltage mutation points in the historical output voltage adjustment map, the topological historical output voltage adjustment map is calculated according to Kirchhoff's law to obtain the output voltage topology map of the series resonance circuit of the power frequency series resonance device;

[0076] Obtain the voltage distribution input node of the output voltage topology map of the series resonance circuit, mark the historical topological node area where the historical voltage mutation point is located in the output voltage topology map of the series resonance circuit, and obtain the voltage distribution of the historical topological node area. Preset the restart probability according to the voltage distribution of the historical topological node area;

[0077] Taking the voltage distribution input node as the initial node, calculate the probability vector of the initial node transferring to the historical topological node area through the restart probability to obtain the transition probability matrix of the output voltage topology map of the series resonance circuit, and repeat the above steps to continuously update and iterate the transition probability matrix;

[0078] Preset the iteration frequency. When the update iteration reaches the iteration frequency, perform convergence processing to generate the final transition probability matrix of the output voltage topology map of the series resonance circuit, and obtain the mutation probability of the historical voltage mutation point in the output voltage topology map of the series resonance circuit according to the final transition probability matrix.

[0079] It should be noted that the power frequency series resonance device is mainly composed of resistors, inductors, and capacitors connected in a specific manner. When the AC voltage frequency in the circuit matches the inherent resonance frequency of the circuit, the inductive reactance of the inductor and the capacitive reactance of the capacitor can be exactly equal to cause resonance. From this, it can be known that when the power frequency series resonance device conducts a partial discharge test on electrical equipment, if there are phenomena such as intermittent supply and instability in its test voltage, it may be due to the circuit control error of frequency response delay caused by the relatively high bandwidth of the inductor and capacitor in the series circuit after the power frequency series resonance device controls the variable-frequency power supply to boost the voltage. It may also be that there is a frequency deviation when the control system of the power frequency series resonance device adjusts the variable-frequency power supply to the resonance frequency. The above two situations both result in the situation where the power frequency series resonance device can never reach the resonance steady state and generate an output voltage mutation, affecting the quality and result accuracy of the withstand voltage test of electrical equipment. Therefore, this method calculates the mutation probability of the historical voltage mutation data of the electrical equipment in the series circuit of the power frequency series resonance device; if the mutation probability is greater than the preset mutation probability, it indicates that there may be an abnormal series control at a certain specific circuit node in the series resonance circuit. Then, in combination with judging whether the circuit node with abnormal series control is in the circuit topology area where the historical voltage mutation data is located, if it is, it indicates that the reason for the unstable output voltage of the power frequency series resonance device is related to the control error of the series resonance circuit. Otherwise, the possibility of the control error of the series circuit is excluded, and the frequency adjustment error factor of the control system is further considered to accurately determine and trace the source of the behavior that affects the abnormal voltage output of the power frequency series resonance device, optimize the intelligent ability of the power frequency series resonance device to solve the resonance steady state anomaly, and improve the test stability of the power frequency series resonance device.

[0080] Further, in a preferred embodiment of the present invention, if the abnormal control topology node of the series resonance circuit with a mutation probability greater than the preset mutation probability is not in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, then the frequency signal at the resonance frequency point is obtained, and the frequency drift generated when the frequency adjustment strategy is adjusted to the frequency signal is calibrated to obtain the first intelligent control scheme, which specifically includes the following steps:

[0081] Mark the topology node with a mutation probability greater than the preset mutation probability in the output voltage topology diagram of the series resonance circuit of the power frequency series resonance device, define it as the abnormal control topology node of the series resonance circuit, and judge whether the abnormal control topology node of the series resonance circuit is in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit;

[0082] If it is not in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, then the preset frequency step and the preset frequency range of the power frequency series resonance device for the electrical equipment to be tested are extracted through initial parameter configuration;

[0083] Obtain the voltage-current curve graph after scanning by frequency scanning technology within a preset frequency range according to a preset frequency step, mark the frequency points with the maximum current value and the minimum voltage value based on the voltage-current curve graph, and obtain multiple resonant frequency points;

[0084] Obtain the current distribution and voltage distribution of each resonant frequency point in the output voltage topology diagram of the series resonant circuit, preset the search range of each resonant frequency point based on the current distribution and voltage distribution, and plot the frequency signals of each resonant frequency point;

[0085] Obtain the communication protocol and control technology of the power frequency series resonant device, determine the frequency adjustment mechanism of the power frequency series resonant device according to the communication protocol and control technology, and retrieve the frequency adjustment strategy of the frequency adjustment mechanism for the power frequency series resonant device;

[0086] Extract the final generated adjustment frequency signal when adjusting the input voltage of the variable frequency power supply to the frequency signals of each resonant frequency point through the frequency adjustment strategy, and at this time, determine whether the adjustment frequency signal is within the search range corresponding to each resonant frequency point;

[0087] If not, perform Hilbert transform on the adjustment frequency signal that is not within the search range of the resonant frequency point and the corresponding frequency signal to obtain the envelope arctangent value of the adjustment frequency signal and the envelope arctangent value of the frequency signal, and calculate the phase difference between the envelope arctangent value of the adjustment frequency signal and the envelope arctangent value of the frequency signal to obtain the instantaneous phase difference;

[0088] Preset the unpacking phase interval, expand the instantaneous phase difference within the unpacking phase interval to solve the time derivative of the instantaneous phase difference, and calculate the frequency offset according to the time derivative to obtain the frequency drift amount of the adjustment frequency signal;

[0089] Based on the frequency drift amount, re-tune the frequency adjustment strategy of the frequency adjustment mechanism for the power frequency series resonant device to obtain the first intelligent control scheme.

[0090] It should be noted that through the analysis of the previous step, it can be seen that if the circuit node with abnormal series control is not within the topological node area where the voltage mutation point is located in the output voltage topology diagram of the series circuit, it indicates that the reason for the unstable output voltage of the power frequency series resonance device may be due to errors in the frequency adjustment strategy pre-established by the control system. Some incorrect frequency adjustment parameters cause a deviation between the adjustment frequency signal finally generated when the power frequency series resonance device increases the frequency of the variable-frequency voltage at a certain node and the resonance frequency, so it cannot match the resonance frequency, resulting in the phenomenon that it is difficult to always maintain a stable resonance state, thus making the output voltage of the power frequency series resonance device unstable when testing power equipment, and greatly reducing the test accuracy of the power frequency series resonance device. This method can determine the frequency signal of the resonance frequency point and the search range of the resonance frequency point, where the search range of the resonance frequency point is the allowable range within which the resonance frequency point can be searched; by analyzing whether the adjustment frequency signal finally generated after frequency modulation of the variable-frequency power supply in the frequency adjustment strategy is within the search range of the corresponding resonance frequency point. If it is not, it indicates that a deviation, that is, a drift phenomenon, has occurred between the actually frequency-modulated adjustment frequency signal and the predetermined frequency signal of the corresponding resonance frequency point. Therefore, the instantaneous phase difference between the two is calculated through Hilbert transform, and the frequency drift amount between the two can be further determined according to the instantaneous phase difference, so as to adjust and repair the boost control error of the frequency adjustment strategy of the power frequency series resonance device for the variable-frequency power supply, thereby achieving a high degree of consistency between the power supply boost frequency and the resonance frequency, improving the resonance matching quality, making the power frequency series resonance device always in a stable resonance state, greatly enhancing the test stability, and having high reliability.

[0091] Further, in a preferred embodiment of the present invention, if the abnormal control topological node of the series resonance circuit with a mutation probability greater than the preset mutation probability is within the historical topological node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, then calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonance point distribution diagram and the accurate resonance point distribution diagram, and perform secondary optimization on the calibrated negative feedback network to obtain a second intelligent control scheme, which specifically includes the following steps:

[0092] S202: If the abnormal control topological node of the series resonance circuit is within the historical topological node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, then obtain the preset frequency step and the preset frequency range of the power frequency series resonance device for the power equipment to be tested through initial parameter configuration;

[0093] S204: Obtain the layout information of all operational amplifiers in the power-frequency series resonance device arranged in the series resonance circuit, divide the preset frequency range into several sub-frequency ranges based on the layout information, and perform precise step-by-step scanning on each sub-frequency range based on the preset frequency step to obtain an accurate resonance point distribution map;

[0094] S206: Obtain the actual resonance point distribution map corresponding to each sub-frequency range when the power-frequency series resonance device generates the historical output voltage regulation map. Taking the accurate resonance point distribution map as a reference benchmark, plan the frequency range where accurate resonance points are missing in the actual resonance point distribution map of each sub-frequency range, and define it as the low-frequency response area;

[0095] S208: Obtain the negative feedback network of the operational amplifier, and at the same time obtain the actual gain adjustment value of the negative feedback network in each low-frequency response area. Calculate the deviation between each actual gain adjustment value and the accurate gain adjustment value to obtain the gain deviation, and determine the quality factor for the negative feedback network to control the bandwidth of the series resonance circuit according to the gain deviation;

[0096] S210: Preset an ideal quality factor, calibrate and initialize the gain control of the feedback network for the operational amplifier according to the quality factor until the quality factor approaches the ideal quality factor, and obtain the calibrated negative feedback network;

[0097] S212: Precisely control the power-frequency series resonance device through the calibrated negative feedback network to output new inductance reactance parameters and new capacitance reactance parameters. If there is still a phenomenon of missing accurate resonance points in the resonance point distribution map after calibration scanning, then construct an adjusted feedback loop compensation network to improve the control accuracy of the operational amplifier, and obtain the second intelligent control scheme.

[0098] It should be noted that the power frequency series resonance device adjusts the parameters of the inductor and capacitor so that the loop resonates at the power frequency, thereby generating a high voltage on the device under test. When the abnormal circuit node in the series control is not within the topological node region where the voltage mutation point is located in the output voltage topology diagram of the series circuit, it indicates that the adjusted parameters of the inductor and capacitor increase the bandwidth of the series circuit, thereby reducing the selection accuracy and high transmission efficiency near the resonance frequency point, resulting in poor frequency response ability of the series resonance circuit and unstable output voltage of the power frequency series resonance device. This method analyzes the missing situation of accurate resonance points in the actual resonance point distribution diagram with the accurate resonance point distribution diagram as the reference benchmark, so as to determine the resonance point region with low frequency response during the historical test of power equipment, that is, the bandwidth increase region; from the frequency transmission characteristics of the series resonance circuit, it can be seen that in order to improve the recognition and passing ability of the resonance frequency, the bandwidth in the series resonance circuit should be kept narrow; therefore, this method determines the quality factor of the negative feedback network controlling the series circuit bandwidth according to the gain deviation between the actual gain adjustment value and the accurate gain adjustment value output by the negative feedback network of the operational amplifier in the series resonance circuit; among them, the quality factor is an important parameter representing the selectivity and bandwidth of the series circuit, and the quality factor can often be controlled by adjusting the component parameters of the inductor, capacitor and resistor. A high-quality factor circuit has a narrow bandwidth, while a low-quality factor circuit has a wide bandwidth. Adjust the gain control of the feedback network for the operational amplifier according to the quality factor, that is, increase the gain to reversely reduce the bandwidth, so as to calibrate the feedback network. The calibrated feedback network can adaptively calibrate the control parameters of the capacitor and inductor according to the accurate gain of the operational amplifier, so as to achieve the precise control effect of the output parameters of each component of the series circuit, greatly improving the frequency response ability of the series resonance circuit to identify the selected resonance point, avoiding the phenomenon of resonance point omission and misjudgment, and further improving the resonance stability of the power frequency series resonance device.

[0099] Further, in a preferred embodiment of the present invention, the calibrated negative feedback network outputs new inductive reactance parameters of the inductor and new capacitive reactance parameters of the capacitor to precisely control the power frequency series resonance device. If there are still missing accurate resonance points in the resonance point distribution diagram after calibration scanning, a adjusted feedback loop compensation network is constructed to improve the control accuracy of the operational amplifier, and a second intelligent control scheme is obtained, which specifically includes the following steps:

[0100] S302: The power frequency series resonance device precisely controlled by the calibrated negative feedback network outputting new inductive reactance parameters of the inductor and new capacitive reactance parameters of the capacitor re-scans the preset frequency range to obtain the resonance point distribution diagram after calibration scanning;

[0101] S304: If there is still a phenomenon that accurate resonance points are missing in the resonance point distribution map after calibration scanning, obtain the model specifications for controlling each operational amplifier in the series resonance circuit, and retrieve the preset gain-bandwidth product of each operational amplifier based on the model specifications in the big data network;

[0102] S306: Obtain the accurate resonance points at the current peak and voltage peak in the accurate resonance point distribution map, defined as peak resonance points, extract the target frequency response value of the negative feedback network of the operational amplifier in response to the peak resonance points, and determine the preset feedback coefficient of the feedback loop compensation network according to the target frequency response value and the preset gain-bandwidth product;

[0103] S308: Introduce the pole analysis algorithm to analyze the change of the pole position of the series resonance circuit in the power frequency series resonance device when scanning the preset frequency range, so as to determine the change of the pole position of the series resonance circuit under the change of the scanning frequency range and the corresponding phase margin, and calculate the actual frequency response value of the series resonance circuit in the power frequency series resonance device when scanning the peak resonance points according to the change of the pole position and the corresponding phase margin;

[0104] S310: Obtain the series resonance knowledge graph based on the big data network, import the model specifications of the operational amplifier into the series resonance knowledge graph for identification, determine the feedback loop compensation network architecture, and initialize the feedback loop compensation network architecture with the preset feedback coefficient;

[0105] S312: Adjust the phase delay between the actual frequency response value and the target frequency response value in the initialized feedback loop compensation network architecture until the feedback coefficient in the output voltage topology map of the series resonance circuit reaches the preset feedback coefficient, and obtain the adjusted feedback loop compensation network;

[0106] S314: Upload the adjusted feedback loop compensation network to the series resonance circuit control terminal of the power frequency series resonance device to improve the frequency response performance of the amplifier for adjusting the inductor and capacitor to scan different frequency ranges, and obtain the second intelligent control scheme.

[0107] It should be noted that the calibrated negative feedback network outputs new inductance reactance parameters and new capacitance reactance parameters to precisely and stably control the bandwidth limit of the series resonance circuit in the power frequency series resonance device. However, when there are still missing accurate resonance points in the resonance point distribution map after being adjusted and scanned by the calibrated negative feedback network, it indicates that it is still difficult to meet the actual frequency response requirements of the inductor and capacitor in the current series resonance circuit after the precise adjustment of the calibrated negative feedback network. This proves that the calibrated negative feedback network may have certain applicability defects for the operational amplifier in the current series resonance circuit, reducing the adaptability of the negative feedback network to adjust the series resonance circuit with different frequency response requirements. This method evaluates whether the series resonance circuit has sufficient phase margin within the target operating frequency range by analyzing the actual frequency response and phase margin of the series resonance circuit in the current power frequency series resonance device when scanning the peak resonance point, so as to avoid oscillation and instability; and adjusts the phase delay between the actual frequency response value and the target frequency response value of the series resonance circuit scanning the peak resonance point until the feedback coefficient reaches the preset feedback coefficient. Among them, the feedback coefficient determines the influence degree of the feedback loop on the gain of the operational amplifier, and a lower feedback coefficient can improve the frequency response and reduce the non-linear distortion; thus, a feedback loop compensation network can be constructed to compensate for the deficiencies and variations of the operational amplifier in different frequency response requirements, improve the frequency response performance of the amplifier to adjust the inductance and capacitance scanning different frequency ranges, further optimize the adaptability of the negative feedback network to adjust the series resonance circuit with different frequency response requirements, so as to maintain the reliability of bandwidth control and improve the resonance stability of the power frequency series resonance device.

[0108] Further, in a preferred embodiment of the present invention, after running the first intelligent control scheme or the second intelligent control scheme, the actual partial discharge test data of the power equipment to be tested is obtained, a tree-shaped discharge dynamic model is constructed based on the actual partial discharge test data, and the partial discharge amplitude is predicted and analyzed based on the tree-shaped discharge dynamic model to generate an early warning signal and an instantaneous protection control signal to cut off the circuit, so as to improve the safety of the withstand voltage test of the power frequency series resonance device. The specific steps are as follows:

[0109] The power equipment to be tested is actually tested by the power frequency series resonance device. During the test, the first intelligent control scheme or the second intelligent control scheme is run to adjust the resonance steady state of the power frequency series resonance device and record the test data to obtain the actual partial discharge test data of the power equipment to be tested;

[0110] A number of uniform time-sequence test intervals are preset, and the actual partial discharge test data corresponding to each uniform time-sequence test interval is extracted from the actual partial discharge test data and defined as a sub-test data group;

[0111] Obtain the discharge signal intensity and discharge signal distribution applied by the power frequency series resonance device to the power equipment under test at each uniform time sequence test interval according to several groups of sub-test data groups, and construct an electrical tree effect time sequence discharge model corresponding to each group of sub-test data groups through model fitting based on the discharge signal intensity and discharge signal distribution;

[0112] Introduce the LSTM algorithm to perform time sequence dynamic calculation on the electrical tree effect time sequence discharge model corresponding to each group of sub-test data groups and construct a model to generate a tree-shaped discharge dynamic model;

[0113] Preset a future time sequence test interval, and predict the discharge state trend of the future time sequence test interval through the tree-shaped discharge dynamic model to determine the actual partial discharge amplitude of the power frequency series resonance device for the power equipment under test at the future time sequence test interval;

[0114] Obtain the historical withstand voltage evaluation information of the power equipment under test, preset the breakdown critical value of the partial discharge test according to the historical withstand voltage evaluation information, and at the same time obtain the lowest partial discharge amplitude required to reach the breakdown critical value, and judge whether the actual partial discharge amplitude exceeds the lowest partial discharge amplitude;

[0115] If it exceeds, control the warning mechanism of the power frequency series resonance device to send out an alarm signal. At this time, calculate the difference between the actual partial discharge amplitude and the lowest partial discharge amplitude to obtain the amplitude deviation rate;

[0116] When the amplitude deviation rate is greater than the preset amplitude deviation rate, generate an instantaneous protection control signal based on the amplitude deviation rate, and immediately cut off the power operation of the power frequency series resonance device through the instantaneous protection control signal when a breakdown phenomenon occurs, so as to improve the safety factor during the withstand voltage test of the power frequency series resonance device.

[0117] It should be noted that when using a power frequency series resonance device to conduct partial discharge tests on electrical equipment, when the voltage output by the power frequency series resonance device exceeds the withstand voltage limit of the electrical equipment, local discharges inside it may cause electrical breakdown of the electrical equipment. Continuous electrical breakdown phenomena are somewhat dangerous and may cause a certain degree of damage to nearby test personnel and electrical equipment. Therefore, it is necessary to promptly cut off the circuit of the power frequency series resonance device to eliminate continuous electrical breakdown phenomena. When an electrical breakdown phenomenon occurs, tree-shaped discharges will appear in the local discharges inside the electrical equipment, which is a precursor to the electrical breakdown phenomenon. Therefore, this method constructs a tree-shaped discharge dynamic model based on the actual partial discharge test data of the power equipment to be tested at a uniform time series test interval, and then predicts the partial discharge trend in the future time series test interval, that is, the actual partial discharge amplitude, according to the tree-shaped discharge dynamic model. If the actual partial discharge amplitude exceeds the minimum partial discharge amplitude required to reach the breakdown critical value, it indicates that the partial discharge in the future time series test interval will cause an electrical breakdown phenomenon. At this time, the warning mechanism of the power frequency series resonance device can be controlled to send out an alarm signal in advance to alert nearby test personnel to stay away and take corresponding defensive measures, and generate an instantaneous protection control signal according to the amplitude deviation rate to cut off the power operation of the power frequency series resonance device, avoiding damage to test personnel and electrical equipment caused by electrical breakdown phenomena, improving the safety factor during the withstand voltage test of the power frequency series resonance device, and preventing fault phenomena caused by too high operating voltage or current of the power frequency series resonance device, ensuring the service life and high safety and reliability.

[0118] In addition, the intelligent control method for a power frequency series resonance device further includes the following steps:

[0119] Obtain the frequency modulation strategy of the power frequency series resonance device, and extract the resonance steady-state values of the power frequency series resonance device at multiple preset time nodes based on the frequency modulation strategy to obtain multiple resonance steady-state values;

[0120] Calculate the resonance frequency matching rate of the power frequency series resonance device at the resonance point according to the multiple resonance steady-state values. If the resonance frequency matching rate is lower than the preset resonance frequency matching rate, obtain the actual frequency modulation error rate of the power frequency series resonance device;

[0121] Obtain the operating parameters corresponding to each control mechanism in the power frequency series resonance device under different preset frequency modulation error rates through the big data network, and calculate the correlation degree between the actual frequency modulation error rate and different preset frequency modulation error rates through the Pearson correlation coefficient to obtain multiple correlation degrees;

[0122] Extract the preset frequency modulation error rate corresponding to the maximum correlation degree among the multiple correlation degrees, and determine the actual operating parameters corresponding to each control mechanism in the power frequency series resonance device under the actual frequency modulation error rate according to the preset frequency modulation error rate corresponding to the maximum correlation degree;

[0123] Obtain the reference operating parameters of each control mechanism, calculate the deviation between the actual operating parameters corresponding to each control mechanism and the reference operating parameters corresponding to each control mechanism, obtain the deviation values of each control mechanism, and regulate the frequency modulation strategy of the power frequency series resonance device based on the deviation values of each control mechanism to eliminate the frequency modulation error of the power frequency series resonance device.

[0124] It should be noted that due to the long-term operation of the power frequency series resonance device under different environmental conditions, certain faults such as aging, wear, or poor contact occur in its internal control mechanisms, resulting in a frequency modulation error when the power frequency series resonance device executes the frequency modulation strategy during the actual test, causing an error rate in the final test result, which is not conducive to the efficient and accurate test of the power frequency series resonance device. This method can precisely regulate the operating parameter errors generated by each control mechanism in the power frequency series resonance device when executing the frequency modulation strategy one by one, thereby eliminating the frequency modulation error of the power frequency series resonance device, improving the accuracy and reliability of the withstand voltage test result, and ensuring the test control quality of the power frequency series resonance device.

[0125] The second aspect of the present invention provides an intelligent control system for a power frequency series resonance device. The intelligent control system for a power frequency series resonance device includes a memory 41 and a processor 42. An intelligent control method program for a power frequency series resonance device is stored in the memory 41. When the intelligent control method program for a power frequency series resonance device is executed by the processor 42, as Figure 4 shown, the following steps are implemented:

[0126] Obtain the historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested, analyze the historical partial discharge test data to construct an output voltage topology diagram of the series resonance circuit, calculate the transition probability matrix of the historical voltage mutation points generated during the test of the series resonance circuit according to the output voltage topology diagram of the series resonance circuit, and obtain the mutation probability of the historical voltage mutation points in the output voltage topology diagram of the series resonance circuit;

[0127] If the abnormal control topology nodes of the series resonance circuit with a mutation probability greater than the preset mutation probability are not in the historical topology node area where the historical voltage mutation points are located in the output voltage topology diagram of the series resonance circuit, obtain the frequency signal of the resonance frequency point, and calibrate the frequency drift generated when the frequency modulation strategy is adjusted to the frequency signal to obtain the first intelligent control scheme;

[0128] If the abnormal control topological node of the series resonant circuit with a mutation probability greater than the preset mutation probability is in the historical topological node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonant circuit, then calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonance point distribution diagram and the accurate resonance point distribution diagram, and perform secondary optimization on the calibrated negative feedback network to obtain a second intelligent control scheme;

[0129] After running the first intelligent control scheme or the second intelligent control scheme, obtain the actual partial discharge test data of the power equipment to be tested, construct a tree-shaped discharge dynamic model based on the actual partial discharge test data, predict and analyze the partial discharge amplitude based on the tree-shaped discharge dynamic model, generate an early warning signal and an instantaneous protection control signal to cut off the circuit, so as to improve the safety of the withstand voltage test of the power frequency series resonance device.

[0130] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. An intelligent control method for a power frequency series resonance device, characterized in that, Including the following steps: Obtain the historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested, analyze the historical partial discharge test data to construct the output voltage topology diagram of the series resonance circuit, calculate the transition probability matrix of the historical voltage mutation points generated during the test of the series resonance circuit according to the output voltage topology diagram of the series resonance circuit, and obtain the mutation probability of the historical voltage mutation points in the output voltage topology diagram of the series resonance circuit; If the abnormal control topology node of the series resonance circuit with a mutation probability greater than the preset mutation probability is not in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, obtain the frequency signal of the resonance frequency point, and calibrate the frequency drift generated when adjusting the frequency strategy to the frequency signal to obtain the first intelligent control scheme; If the abnormal control topology node of the series resonance circuit with a mutation probability greater than the preset mutation probability is in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonance point distribution diagram and the accurate resonance point distribution diagram, and perform secondary optimization on the calibrated negative feedback network to obtain the second intelligent control scheme; After running the first intelligent control scheme or the second intelligent control scheme, obtain the actual partial discharge test data of the power equipment to be tested, construct a tree-shaped discharge dynamic model according to the actual partial discharge test data, predict and analyze the partial discharge amplitude based on the tree-shaped discharge dynamic model, generate a warning signal and an instantaneous protection control signal to cut off the circuit, so as to improve the safety of the withstand voltage test of the power frequency series resonance device.

2. The intelligent control method of a power frequency series resonance device according to claim 1, wherein The steps of obtaining the historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested, analyzing the historical partial discharge test data to construct the output voltage topology diagram of the series resonance circuit, calculating the transition probability matrix of the historical voltage mutation points generated during the test of the series resonance circuit according to the output voltage topology diagram of the series resonance circuit, and obtaining the mutation probability of the historical voltage mutation points in the output voltage topology diagram of the series resonance circuit specifically include the following steps: Obtain the power equipment to be tested of the power frequency series resonance device and the test log, and retrieve the historical partial discharge test data of the power equipment to be tested through the test log; Construct a cumulative distribution partial discharge map according to the historical partial discharge test data, and strip the historical output voltage adjustment map of the power equipment to be tested based on the cumulative distribution partial discharge map; Obtain the initialization parameter configuration when the power frequency series resonance device generates the historical output voltage adjustment map, extract the normal output voltage waveform of the power equipment to be tested through the initialization parameter configuration, and preset the allowable adjustment fluctuation range of the output voltage according to the normal output voltage waveform; Based on the allowable adjustment fluctuation range, the output voltage adjustment value outside the allowable adjustment fluctuation range is calibrated as a historical voltage mutation point. If there is at least one or more historical voltage mutation points in the historical output voltage adjustment map, the topological historical output voltage adjustment map is calculated according to Kirchhoff's law to obtain the output voltage topology map of the series resonance circuit of the power frequency series resonance device; Obtain the voltage distribution input nodes of the output voltage topology map of the series resonance circuit, mark the historical topological node area where the historical voltage mutation point is located in the output voltage topology map of the series resonance circuit, and obtain the voltage distribution of the historical topological node area. Preset the restart probability according to the voltage distribution of the historical topological node area; Taking the voltage distribution input node as the initial node, calculate the probability vector of the initial node transferring to the historical topological node area through the restart probability to obtain the transition probability matrix of the output voltage topology map of the series resonance circuit, and repeat the above steps to continuously update and iterate the transition probability matrix; Preset the iteration frequency. When the update iteration reaches the iteration frequency, perform convergence processing to generate the final transition probability matrix of the output voltage topology map of the series resonance circuit, and obtain the mutation probability of the historical voltage mutation point in the output voltage topology map of the series resonance circuit according to the final transition probability matrix.

3. An intelligent control method for a power frequency series resonance device according to claim 1, characterized in that, If the abnormal control topological node of the series resonance circuit with a mutation probability greater than the preset mutation probability is not in the historical topological node area where the historical voltage mutation point is located in the output voltage topology map of the series resonance circuit, obtain the frequency signal of the resonance frequency point, and calibrate the frequency drift generated when the adjustment frequency strategy is adjusted to the frequency signal to obtain the first intelligent control scheme, which specifically includes the following steps: Mark the topological nodes with a mutation probability greater than the preset mutation probability in the output voltage topology map of the series resonance circuit of the power frequency series resonance device, define them as the abnormal control topological nodes of the series resonance circuit, and judge whether the abnormal control topological nodes of the series resonance circuit are in the historical topological node area where the historical voltage mutation point is located in the output voltage topology map of the series resonance circuit; If it is not in the historical topological node area where the historical voltage mutation point is located in the output voltage topology map of the series resonance circuit, extract the preset frequency step and preset frequency range of the power frequency series resonance device for the power equipment to be tested through initialization parameter configuration; Obtain the voltage-current curve graph after scanning the preset frequency range according to the preset frequency step by frequency scanning technology, and mark the frequency points with the largest current value and the smallest voltage value according to the voltage-current curve graph to obtain multiple resonance frequency points; Obtain the current distribution and voltage distribution of each resonance frequency point in the output voltage topology map of the series resonance circuit, preset the search range of each resonance frequency point based on the current distribution and voltage distribution, and draw the frequency signal of each resonance frequency point; Obtain the communication protocol and control technology of the power frequency series resonance device, determine the frequency adjustment mechanism of the power frequency series resonance device according to the communication protocol and control technology, and retrieve the frequency adjustment strategy of the frequency adjustment mechanism for the power frequency series resonance device; Extract the final generated adjustment frequency signal when adjusting the input voltage of the variable-frequency power supply to each resonant frequency point through the frequency adjustment strategy. At this time, determine whether the adjustment frequency signal is within the search range corresponding to each resonant frequency point; If not, perform Hilbert transform on the adjustment frequency signal that is not within the resonant frequency point search range and the corresponding frequency signal to obtain the envelope arctangent value of the adjustment frequency signal and the envelope arctangent value of the frequency signal, calculate the phase difference between the envelope arctangent value of the adjustment frequency signal and the envelope arctangent value of the frequency signal, and obtain the instantaneous phase difference; Preset the unpacking phase interval, and expand the instantaneous phase difference in the unpacking phase interval to solve the time derivative of the instantaneous phase difference, and calculate the frequency offset according to the time derivative to obtain the frequency drift amount of the adjustment frequency signal; Based on the frequency drift amount, re-tune the frequency adjustment strategy of the frequency adjustment mechanism for the power frequency series resonance device to obtain the first intelligent control scheme.

4. The intelligent control method of a power frequency series resonance device according to claim 1, characterized in that, If the abnormal control topology node of the series resonance circuit with a mutation probability greater than the preset mutation probability is in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, then calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonance point distribution diagram and the accurate resonance point distribution diagram, and perform secondary optimization on the calibrated negative feedback network to obtain the second intelligent control scheme, which specifically includes the following steps: If the abnormal control topology node of the series resonance circuit is within the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, then obtain the preset frequency step and preset frequency range of the power frequency series resonance device for the power equipment to be tested through initial parameter configuration; Obtain the layout information of all operational amplifiers set in the series resonance circuit by the power frequency series resonance device, divide the preset frequency range into several sub-frequency ranges based on the layout information, and perform precise step scanning on each sub-frequency range based on the preset frequency step to obtain the accurate resonance point distribution diagram; Obtain the actual resonance point distribution diagram corresponding to each sub-frequency range when the power frequency series resonance device generates the historical output voltage adjustment map. Taking the accurate resonance point distribution diagram as the reference benchmark, plan the frequency range where the accurate resonance points are missing in the actual resonance point distribution diagram of each sub-frequency range, which is defined as the low-frequency response area; Obtain the negative feedback network of the operational amplifier, and at the same time obtain the actual gain adjustment value of the negative feedback network in each low-frequency response area, calculate the deviation between each actual gain adjustment value and the accurate gain adjustment value to obtain the gain deviation, and determine the quality factor of the negative feedback network controlling the bandwidth of the series resonance circuit according to the gain deviation; Preset the ideal quality factor, calibrate and initialize the gain control of the feedback network for the operational amplifier according to the quality factor until the quality factor approaches the ideal quality factor to obtain the calibrated negative feedback network; The negative feedback network completed by calibration outputs new inductance reactance parameters and new capacitance reactance parameters to precisely control the power frequency series resonance device. If there are still missing accurate resonance points in the resonance point distribution map after calibration scanning, then construct an adjusted feedback loop compensation network to improve the control accuracy of the operational amplifier, and obtain the second intelligent control scheme.

5. The intelligent control method of a power frequency series resonance device according to claim 4, characterized in that, The negative feedback network completed by calibration outputs new inductance reactance parameters and new capacitance reactance parameters to precisely control the power frequency series resonance device. If there are still missing accurate resonance points in the resonance point distribution map after calibration scanning, then construct an adjusted feedback loop compensation network to improve the control accuracy of the operational amplifier, and obtain the second intelligent control scheme, which specifically includes the following steps: The negative feedback network completed by calibration outputs new inductance reactance parameters and new capacitance reactance parameters to precisely control the power frequency series resonance device to re-scan the preset frequency range, and obtain the resonance point distribution map after calibration scanning; If there are still missing accurate resonance points in the resonance point distribution map after calibration scanning compared with the accurate resonance point distribution map, then obtain the model specifications for controlling each operational amplifier in the series resonance circuit, and retrieve the preset gain-bandwidth product of each operational amplifier based on the model specifications in the big data network; Obtain the accurate resonance points at the current peak and voltage peak in the accurate resonance point distribution map, define them as peak resonance points, extract the target frequency response value of the negative feedback network of the operational amplifier in response to the peak resonance points, and determine the preset feedback coefficient of the feedback loop compensation network according to the target frequency response value and the preset gain-bandwidth product; Introduce the pole analysis algorithm to analyze the change of the pole position of the series resonance circuit in the power frequency series resonance device when scanning the preset frequency range, so as to determine the change of the pole position of the series resonance circuit under the change of the scanning frequency range and the corresponding phase margin, and calculate the actual frequency response value of the series resonance circuit in the power frequency series resonance device scanning the peak resonance point according to the change of the pole position and the corresponding phase margin; Obtain the series resonance knowledge graph based on the big data network, import the model specifications of the operational amplifier into the series resonance knowledge graph for identification, determine the feedback loop compensation network architecture, and initialize the feedback loop compensation network architecture with the preset feedback coefficient; Adjust the phase delay between the actual frequency response value and the target frequency response value in the initialized feedback loop compensation network architecture until the feedback coefficient in the output voltage topology diagram of the series resonance circuit reaches the preset feedback coefficient, and obtain the adjusted feedback loop compensation network; Upload the adjusted feedback loop compensation network to the series resonance circuit control terminal of the power frequency series resonance device to improve the frequency response performance of the amplifier for adjusting the inductance and capacitance to scan different frequency ranges, and obtain the second intelligent control scheme.

6. The intelligent control method of a power frequency series resonance device according to claim 1, characterized in that After running the first intelligent control scheme or the second intelligent control scheme, obtain the actual partial discharge test data of the power equipment to be tested, construct a tree-shaped discharge dynamic model according to the actual partial discharge test data, predict and analyze the partial discharge amplitude based on the tree-shaped discharge dynamic model, generate a warning signal and an instantaneous protection control signal to cut off the circuit, so as to improve the safety of the withstand voltage test of the power frequency series resonance device, specifically including the following steps: Perform an actual test on the power equipment to be tested through a power frequency series resonance device. During the test, run the first intelligent control scheme or the second intelligent control scheme to adjust the resonance steady state of the power frequency series resonance device and record the test data, so as to obtain the actual partial discharge test data of the power equipment to be tested; Preset several uniform time series test intervals, extract the actual partial discharge test data corresponding to each uniform time series test interval from the actual partial discharge test data, and define it as a sub-test data group; Obtain the discharge signal intensity and discharge signal distribution applied to the power equipment to be tested by the power frequency series resonance device at each uniform time series test interval according to several groups of sub-test data groups, and perform model fitting based on the discharge signal intensity and discharge signal distribution to construct an electrical tree-shaped effect time series discharge model corresponding to each group of sub-test data groups; Introduce the LSTM algorithm to perform time series dynamic calculation on the electrical tree-shaped effect time series discharge model corresponding to each group of sub-test data groups and construct a model to generate a tree-shaped discharge dynamic model; Preset a future time series test interval, and predict the discharge state trend of the future time series test interval through the tree-shaped discharge dynamic model to determine the actual partial discharge amplitude of the power equipment to be tested when the power frequency series resonance device is in the future time series test interval; Obtain the historical withstand voltage evaluation information of the power equipment to be tested, preset the breakdown critical value of the partial discharge test according to the historical withstand voltage evaluation information, and at the same time obtain the lowest partial discharge amplitude required to reach the breakdown critical value, and judge whether the actual partial discharge amplitude exceeds the lowest partial discharge amplitude; If it exceeds, control the warning mechanism of the power frequency series resonance device to send out an alarm signal. At this time, calculate the difference between the actual partial discharge amplitude and the lowest partial discharge amplitude to obtain the amplitude deviation rate; When the amplitude deviation rate is greater than the preset amplitude deviation rate, generate an instantaneous protection control signal based on the amplitude deviation rate, and immediately cut off the power operation of the power frequency series resonance device through the instantaneous protection control signal when a breakdown phenomenon occurs, so as to improve the safety factor during the withstand voltage test of the power frequency series resonance device.

7. An intelligent control system for a power frequency series resonance device, characterized in that, The intelligent control system of a power frequency series resonance device includes a memory and a processor. A program of an intelligent control method for a power frequency series resonance device is stored in the memory. When the program of the intelligent control method for a power frequency series resonance device is executed by the processor, the following steps are implemented: Obtain the historical partial discharge test data of the power frequency series resonance device for the power equipment to be tested, analyze the historical partial discharge test data to construct the output voltage topology diagram of the series resonance circuit, calculate the transition probability matrix of the historical voltage mutation points generated during the test of the series resonance circuit according to the output voltage topology diagram of the series resonance circuit, and obtain the mutation probability of the historical voltage mutation points in the output voltage topology diagram of the series resonance circuit; If the abnormal control topology node of the series resonance circuit with a mutation probability greater than the preset mutation probability is not in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, obtain the frequency signal of the resonance frequency point, and calibrate the frequency drift generated when the frequency adjustment strategy is adjusted to the frequency signal to obtain the first intelligent control scheme; If the abnormal control topology node of the series resonance circuit with a mutation probability greater than the preset mutation probability is in the historical topology node area where the historical voltage mutation point is located in the output voltage topology diagram of the series resonance circuit, calibrate the gain control of the feedback network for the operational amplifier according to the gain difference between the actual resonance point distribution diagram and the accurate resonance point distribution diagram, and perform secondary optimization on the calibrated negative feedback network to obtain the second intelligent control scheme; After running the first intelligent control scheme or the second intelligent control scheme, obtain the actual partial discharge test data of the power equipment to be tested, construct a tree-shaped discharge dynamic model according to the actual partial discharge test data, predict and analyze the partial discharge amplitude based on the tree-shaped discharge dynamic model, generate an early warning signal and an instantaneous protection control signal to cut off the circuit, so as to improve the safety of the withstand voltage test of the power frequency series resonance device.

Images