A method, system, device and storage medium for wireless monitoring of a zinc oxide surge arrester

Abstract

The application discloses a zinc oxide lightning arrester wireless monitoring method, system, device and storage medium, and comprises the following steps: receiving an initial lightning arrester voltage signal and a leakage current signal of a zinc oxide lightning arrester to be monitored in real time; performing remote phase synchronization on the initial lightning arrester voltage signal to obtain an intermediate lightning arrester voltage signal corresponding to a preset operating voltage signal of the zinc oxide lightning arrester to be monitored and being in the same phase; determining a resistive current effective value and a total current effective value according to a lightning arrester voltage value corresponding to the intermediate lightning arrester voltage signal and a leakage current value corresponding to the leakage current signal; obtaining an insulation performance grade and an operating risk grade corresponding to the zinc oxide lightning arrester to be monitored according to a ratio between the resistive current effective value and the total current effective value; and solving the technical problem that existing online monitoring technology is prone to causing secondary short circuit of a voltage transformer, thereby causing a safety hazard. The application can monitor the operating condition of the zinc oxide lightning arrester in real time without power interruption.

Description

Technical Field

[0001] This invention relates to the field of zinc oxide surge arrester technology, and in particular to a wireless monitoring method, system, device and storage medium for zinc oxide surge arresters. Background Technology

[0002] Metal oxide surge arresters (MOAs) are crucial protective devices for ensuring the safe operation of power systems. Fluctuations in system voltage have a significant impact on the resistive leakage current of the MOA. Prolonged, uninterrupted operation of the MOA accelerates the aging of its zinc oxide varistors, leading to thermal breakdown and potentially causing a busbar or line circuit break in the substation—a very serious consequence. Furthermore, inadequate sealing can cause moisture to enter the arrester, or water may seep in during installation, increasing the power frequency current and potentially leading to internal flashover and even an explosion. These faults can all be detected by changes in the resistive leakage current; therefore, it is necessary to monitor changes in the MOA's resistive leakage current to predict potential faults.

[0003] In existing technologies, the resistive leakage current of MOA is usually detected by periodically shutting down the zinc oxide surge arrester for testing. However, the above method requires shutting down the main equipment during the power outage test, and the test cycle is long, resulting in significant economic losses.

[0004] Therefore, existing online detection systems analyze voltage and leakage current remotely. However, the voltage and current obtained by the above method are not in the same location, requiring long-distance wiring, which can easily cause secondary short circuits in the voltage transformer, leading to safety hazards. Summary of the Invention

[0005] This invention provides a wireless monitoring method, system, device, and storage medium for zinc oxide surge arresters. It solves the technical problem that existing online monitoring systems analyze voltage and leakage current remotely, but the voltage and current obtained in the above methods are not in the same location, requiring long-distance wiring, which can easily cause secondary short circuits in voltage transformers and lead to safety hazards.

[0006] The first aspect of this invention provides a wireless monitoring method for zinc oxide surge arresters, the method comprising:

[0007] Real-time reception of the initial arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored;

[0008] The initial surge arrester voltage signal is remotely phase synchronized to obtain an intermediate surge arrester voltage signal that is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored.

[0009] Based on the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal, determine the effective value of the resistive current and the effective value of the total current.

[0010] The insulation performance level and operational risk level of the zinc oxide surge arrester to be monitored are obtained based on the ratio between the effective value of the resistive current and the effective value of the total current.

[0011] Optionally, the step of receiving the initial arrester voltage signal and leakage current signal of the zinc oxide arrester to be monitored in real time includes:

[0012] The initial surge arrester voltage signal is collected in real time from the bus or line corresponding to the zinc oxide surge arrester to be monitored by a voltage transformer.

[0013] Leakage current signals are collected in real time from the zinc oxide surge arrester to be monitored;

[0014] The initial surge arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored are received in real time through the wireless communication unit.

[0015] Optionally, the step of remotely synchronizing the initial surge arrester voltage signal to obtain an intermediate surge arrester voltage signal that is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored includes:

[0016] The initial surge arrester voltage signal is subjected to low-pass filtering, DA conversion, and GPS timing to obtain the voltage zero-crossing time of the initial surge arrester voltage signal;

[0017] The phase angle is determined based on the zero-crossing time difference between the voltage zero-crossing time and the zero-crossing time of the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored;

[0018] The initial surge arrester voltage is remotely phase-synchronized according to the phase angle to obtain an intermediate surge arrester voltage that is in the same phase as the operating voltage.

[0019] Optionally, the step of determining the effective value of the resistive current and the effective value of the total current based on the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal includes:

[0020] The intermediate surge arrester voltage signal is phase-shifted until it is in the same phase as the capacitive current signal corresponding to the leakage current signal, thus obtaining the target surge arrester voltage signal.

[0021] Based on the surge arrester voltage value corresponding to the target surge arrester voltage signal and the leakage current value corresponding to the leakage current signal, determine the effective value of resistive current and the effective value of capacitive current.

[0022] The total effective current value is obtained by calculating the arithmetic square root of the sum of the squares of the effective values ​​of the resistive and capacitive currents.

[0023] Optionally, the step of determining the effective values ​​of the resistive current and capacitive current based on the surge arrester voltage value corresponding to the target surge arrester voltage signal and the leakage current value corresponding to the leakage current signal includes:

[0024] The voltage value of the surge arrester is adjusted according to a preset multiple to obtain the target voltage value of the surge arrester.

[0025] The target leakage current value is obtained by subtracting the target surge arrester voltage value from the leakage current value.

[0026] The voltage value of the surge arrester and the target leakage current value are orthogonally calculated to obtain an orthogonal result;

[0027] Determine whether the orthogonal result is the target threshold;

[0028] If the orthogonal result is not the target threshold, then proceed to the step of adjusting the surge arrester voltage value by a preset multiple to obtain the target surge arrester voltage value;

[0029] If the orthogonal result is the target threshold, then the target leakage current value is determined as a resistive current value, and the target surge arrester voltage value is determined as a capacitive current value;

[0030] The corresponding effective values ​​of resistive current and capacitive current are generated according to the resistive current value and the capacitive current value.

[0031] Optionally, the step of generating corresponding effective values ​​of resistive current and capacitive current according to the resistive current value and the capacitive current value includes:

[0032] By acquiring the resistive current signal corresponding to the resistive current value;

[0033] The resistive current signal is amplified, divided, and low-pass filtered to obtain the effective value of the resistive current corresponding to the resistive current signal.

[0034] By acquiring the capacitive current signal corresponding to the capacitive current value;

[0035] The capacitive current signal is amplified, divided, and low-pass filtered to obtain the effective value of the capacitive current corresponding to the capacitive current signal.

[0036] Optionally, the step of obtaining the insulation performance and operational risk of the zinc oxide surge arrester to be monitored based on the ratio of the effective value of the resistive current to the effective value of the total current includes:

[0037] Calculate the ratio between the effective value of the resistive current and the effective value of the total current;

[0038] Match the corresponding performance level and risk level from the preset key value table according to the risk threshold range in which the ratio is located;

[0039] The performance level is determined to be the insulation performance level corresponding to the zinc oxide surge arrester to be monitored;

[0040] The risk level is determined as the operational risk level corresponding to the zinc oxide surge arrester to be monitored.

[0041] A second aspect of the present invention provides a wireless monitoring system for zinc oxide surge arresters, the system comprising:

[0042] The surge arrester voltage acquisition module is used to receive the initial surge arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored in real time;

[0043] The first surge arrester voltage synchronization module is used to remotely synchronize the initial surge arrester voltage signal to obtain an intermediate surge arrester voltage signal that is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored.

[0044] The surge arrester full current analysis module is used to determine the effective value of resistive current and the effective value of full current based on the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal.

[0045] The second surge arrester voltage synchronization module is used to obtain the insulation performance level and operating risk level of the zinc oxide surge arrester to be monitored based on the ratio between the effective value of the resistive current and the effective value of the total current.

[0046] A third aspect of the present invention provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the wireless monitoring method for zinc oxide surge arresters as described in any of the preceding claims.

[0047] The fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed, implements the wireless monitoring method for zinc oxide surge arresters as described in any of the preceding claims.

[0048] As can be seen from the above technical solutions, the present invention has the following advantages:

[0049] This invention receives the initial arrester voltage signal and leakage current signal of the zinc oxide surge arrester under monitoring in real time. It analyzes the phase of the initial arrester voltage signal and performs remote phase synchronization until the phase of the initial arrester voltage signal is in the same phase as the preset operating signal of the zinc oxide surge arrester under monitoring, generating an intermediate arrester voltage signal. Based on the arrester voltage value corresponding to the intermediate arrester voltage signal and the leakage current value corresponding to the leakage current signal, it determines the effective value of the resistive current and the effective value of the total current. The ratio between the effective value of the resistive current and the effective value of the total current is calculated to obtain the insulation performance level and operational risk level of the zinc oxide surge arrester under monitoring. This invention solves the technical problem of existing online monitoring systems that analyze voltage and leakage current remotely. However, the voltage and current obtained in the above methods are not in the same location, requiring long-distance wiring, which can easily cause secondary short circuits in the voltage transformer, leading to safety hazards. This invention enables real-time wireless monitoring of the operating status of each zinc oxide surge arrester, allowing for timely assessment of the insulation performance level and operational risk level of the zinc oxide surge arrester without power interruption. This allows for early prediction of potential faults and the development of corresponding solutions based on the predicted results. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0051] Figure 1 A flowchart illustrating the steps of a wireless monitoring method for zinc oxide surge arresters provided in this embodiment of the invention;

[0052] Figure 2 A flowchart illustrating the steps of a wireless monitoring method for zinc oxide surge arresters provided in this embodiment of the invention;

[0053] Figure 3 A flowchart illustrating the steps of a wireless monitoring method for zinc oxide surge arresters provided in this embodiment of the invention;

[0054] Figure 4 A schematic diagram showing the phase relationship between the RMS values ​​of the total current, capacitive current, and resistive current provided for embodiments of the present invention;

[0055] Figure 5 This is a structural block diagram of a wireless monitoring system for zinc oxide surge arresters provided in an embodiment of the present invention. Detailed Implementation

[0056] This invention provides a wireless monitoring method, system, device, and storage medium for zinc oxide surge arresters. It addresses the technical problem that existing online monitoring systems analyze voltage and leakage current remotely, but the voltage and current obtained in the above method are not in the same location, requiring long-distance wiring, which can easily cause secondary short circuits in voltage transformers and lead to safety hazards.

[0057] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0058] Please see Figure 1 , Figure 1 A flowchart illustrating the steps of a wireless monitoring method for zinc oxide surge arresters provided in an embodiment of the present invention.

[0059] This invention provides a wireless monitoring method for zinc oxide surge arresters, which includes the following steps:

[0060] Step 101: Receive the initial arrester voltage signal and leakage current signal of the zinc oxide arrester to be monitored in real time.

[0061] It should be noted that zinc oxide surge arresters are devices used to protect electrical equipment. Due to their nonlinear characteristics, only microamperes of current flow under normal voltage. When a lightning strike or system circuit fault occurs, the voltage at the arrester terminals rises sharply, and the internal dynamic insulation resistance drops rapidly, discharging excess voltage to the ground, thereby protecting the safety of the electrical equipment.

[0062] Surge arrester voltage refers to the voltage on the secondary side of the voltage transformer corresponding to the phase line of the zinc oxide surge arrester to be monitored;

[0063] Leakage current refers to the current flowing through the insulation of a surge arrester when there is no fault and voltage is applied. Therefore, leakage current is one of the important indicators for measuring the insulation performance of zinc oxide surge arresters and is an important indicator of product safety performance.

[0064] In this embodiment of the invention, it is necessary to collect and receive the initial surge arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored in real time, so as to predict in advance whether there is a fault in the zinc oxide surge arrester, and then make a corresponding handling plan based on the prediction result.

[0065] Step 102: Perform remote phase synchronization on the initial surge arrester voltage signal to obtain an intermediate surge arrester voltage signal that is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored.

[0066] It should be noted that the preset operating voltage refers to the preset operating voltage corresponding to the zinc oxide surge arrester to be monitored. Under normal circumstances, the phase difference between the bus operating voltage and the capacitive current of the zinc oxide surge arrester is 90°, while the resistive current and the operating voltage are in phase.

[0067] In this embodiment of the invention, since the phase of the initial surge arrester voltage signal of each zinc oxide surge arrester to be monitored may be inconsistent with the phase of the preset operating voltage signal, the initial surge arrester voltage signal is first remotely phase synchronized until it is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored, so that the phase difference between the intermediate surge arrester voltage signal and the capacitive current signal obtained after remote phase synchronization is 90°, and the phase of the intermediate surge arrester voltage signal and the resistive current signal is the same.

[0068] Step 103: Determine the effective value of the resistive current and the effective value of the total current based on the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal.

[0069] It should be noted that leakage current consists of capacitive current and resistive current, and the sum of the two is called the total current. The effective value refers to the value of the DC current or voltage when a DC current and an AC current are passed through the same resistor, respectively, and the electrical energy consumed by them after one AC cycle is equal.

[0070] In this embodiment of the invention, the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal are obtained. The surge arrester voltage value is adjusted by a factor, and the surge arrester voltage value after adjustment and the leakage current value corresponding to the leakage current signal are subtracted to obtain the subtraction result. The surge arrester voltage value and the subtraction result are then orthogonally calculated to obtain the effective value of resistive current and the effective value of total current.

[0071] Step 104: Based on the ratio between the effective value of resistive current and the effective value of total current, obtain the insulation performance level and operational risk level of the zinc oxide surge arrester to be monitored.

[0072] It should be noted that, according to the preventive testing regulations for power equipment, the ratio of the effective value of resistive current to the effective value of the total current can be used to determine the insulation performance of the surge arrester. Since the metal oxide zinc surge arrester is capacitive, theoretically, the leakage current of a normal surge arrester is capacitive. However, due to the stray resistance inside the surge arrester, a small portion of resistive current will pass through. Often, the resistive current only accounts for 10% to 20% of the total current. When the resistive current increases, the total current will also increase, and the insulation performance of the surge arrester will also decrease accordingly, resulting in adverse effects such as internal moisture absorption or insulation damage.

[0073] In a specific embodiment, the ratio between the effective value of resistive current and the effective value of total current is calculated to obtain the proportion between the effective value of resistive current and the effective value of total current. Based on the performance level and risk level corresponding to the proportion, the insulation performance level and operational risk level of the zinc oxide surge arrester to be monitored are obtained.

[0074] This invention receives the initial arrester voltage signal and leakage current signal of the zinc oxide surge arrester under monitoring in real time. It analyzes the phase of the initial arrester voltage signal and performs remote phase synchronization until the phase of the initial arrester voltage signal is in the same phase as the preset operating signal of the zinc oxide surge arrester under monitoring, generating an intermediate arrester voltage signal. Based on the arrester voltage value corresponding to the intermediate arrester voltage signal and the leakage current value corresponding to the leakage current signal, it determines the effective value of the resistive current and the effective value of the total current. The ratio between the effective value of the resistive current and the effective value of the total current is calculated to obtain the insulation performance level and operational risk level of the zinc oxide surge arrester under monitoring. This invention solves the technical problem of existing online monitoring systems that analyze voltage and leakage current remotely. However, the voltage and current obtained in the above methods are not in the same location, requiring long-distance wiring, which can easily cause secondary short circuits in the voltage transformer, leading to safety hazards. This invention enables real-time wireless monitoring of the operating status of each zinc oxide surge arrester, allowing for timely assessment of the insulation performance level and operational risk level of the zinc oxide surge arrester without power interruption. This allows for early prediction of potential faults and the development of corresponding solutions based on the predicted results.

[0075] Please see Figure 2-4 , Figure 2 A flowchart illustrating the steps of a wireless monitoring method for zinc oxide surge arresters provided in an embodiment of the present invention.

[0076] This invention provides a wireless monitoring method for zinc oxide surge arresters, which includes the following steps:

[0077] Step 201: Collect the initial surge arrester voltage signal in real time from the bus or line corresponding to the zinc oxide surge arrester to be monitored through a voltage transformer.

[0078] It should be noted that a voltage transformer is an instrument used to transform voltage. The main purpose of a voltage transformer is to supply power to measuring instruments and relay protection devices, to measure the voltage, power and energy of a line, or to protect valuable equipment, motors and transformers in the line when a fault occurs.

[0079] In a specific embodiment, the initial surge arrester voltage is mainly collected from the bus or line through a voltage transformer. The amplitude of the initial surge arrester voltage is generally a fixed value, which is only related to the voltage level. For example, for a 110kV surge arrester, its voltage is 110 / 1.732 = 63.5kV, and it is 100 / 1.732 = 57.7V on the secondary side of the voltage transformer. Since this voltage is almost constant, the amplitude is not important when collecting the voltage signal; only the phase needs to be collected.

[0080] Step 202: Collect leakage current signals from the zinc oxide surge arrester to be monitored in real time.

[0081] In a specific embodiment, a leakage current signal is collected from the zinc oxide surge arrester to be monitored using a current transformer.

[0082] Step 203: Receive the initial surge arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored in real time through the wireless communication unit.

[0083] It should be noted that the initial surge arrester voltage signal and leakage current signal acquired at the beginning are both real-time signals, with phase and amplitude, and are respectively analog signals of the initial surge arrester voltage signal and leakage current signal, such as... Figure 3 As shown, the initial surge arrester voltage signal analog signal and leakage current analog signal need to be filtered by low-pass filter, and then converted by AD into initial surge arrester voltage signal digital signal and leakage current digital signal before entering the MCU for effective value calculation.

[0084] In this embodiment of the invention, the initial surge arrester voltage signal is mainly collected from the bus or line through a voltage transformer, while the leakage current signal is directly collected at the zinc oxide surge arrester to be monitored. Since the two locations are far apart, the wireless communication unit is divided into two parts, which are respectively set at the initial surge arrester voltage collection point and the leakage current collection point. The two parts are connected by a wireless communication unit to receive the initial surge arrester voltage digital signal and the leakage current digital signal in real time. Specifically, the wireless communication unit can adopt industrial WiFi, mobile WiFi, etc., depending on the specific situation. Preferably, this invention uses industrial WiFi, which can basically cover the substation site area.

[0085] Step 204: Perform remote phase synchronization on the initial surge arrester voltage signal to obtain an intermediate surge arrester voltage signal that is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored.

[0086] Optionally, step 204 may include the following steps S11-S13:

[0087] S11. Perform low-pass filtering, DA conversion, and GPS timing on the initial surge arrester voltage signal to obtain the voltage zero-crossing time of the initial surge arrester voltage signal;

[0088] S12. Determine the phase angle based on the zero-crossing time difference between the voltage zero-crossing time and the zero-crossing time of the preset operating voltage signal corresponding to the zinc oxide arrester to be monitored;

[0089] S13. Perform remote phase synchronization of the initial surge arrester voltage according to the phase angle to obtain the intermediate surge arrester voltage that is in the same phase as the operating voltage.

[0090] It should be noted that the initial surge arrester voltage signal is the initial surge arrester voltage digital signal; the present invention uses a GPS chip for timing, the GPS output is 1PPS, with the pulse leading edge as the reference timing edge, and the accuracy is generally between tens of ns and 1μs, while the fundamental frequency of the surge arrester in operation is the power frequency signal, that is, a cycle of 20ms. The GPS accuracy can meet the application requirements of the scenario.

[0091] In this embodiment of the invention, the initial surge arrester voltage digital signal is low-pass filtered and then converted into an analog signal by a DA converter. The initial surge arrester voltage waveform can be plotted according to the analog signal, and GPS timing is applied to the waveform. When the initial surge arrester voltage signal crosses zero from negative to positive or from positive to negative according to the waveform, the zero-crossing time is recorded as T1. At the same time, the zero-crossing time of the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored is obtained, and the phase angle is determined based on the difference between the two zero-crossing time. Thus, the initial surge arrester voltage signal is remotely phase synchronized until it is in the same phase as the operating voltage, generating an intermediate surge arrester voltage.

[0092] A sine wave U0 corresponding to the intermediate surge arrester voltage can be emitted after T1+N*T, where T is the surge arrester voltage period, i.e., the power frequency period of 20ms, and N is an integer.

[0093] Step 205: Determine the effective value of the resistive current and the effective value of the total current based on the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal.

[0094] Optionally, step 205 further includes the following steps S21-S23:

[0095] S21. Phase shift the intermediate surge arrester voltage signal until it is in the same phase as the capacitive current signal corresponding to the leakage current signal to obtain the target surge arrester voltage signal.

[0096] S22. Determine the effective values ​​of resistive current and capacitive current based on the surge arrester voltage value corresponding to the target surge arrester voltage signal and the leakage current value corresponding to the leakage current signal.

[0097] S23. Calculate the arithmetic square root of the sum of the squares of the effective values ​​of the resistive current and the effective values ​​of the capacitive current to obtain the effective value of the total current.

[0098] It should be noted that leakage current consists of capacitive current and resistive current, and the sum of the two is called the total current. Under normal circumstances, the phase difference between the bus operating voltage and the capacitive current of a zinc oxide surge arrester is 90°, while the resistive current and the operating voltage are in phase.

[0099] In embodiments of the present invention, such as Figure 3 As shown, the intermediate surge arrester voltage signal is remotely phase-synchronized until it is in the same phase as the operating voltage signal corresponding to the zinc oxide surge arrester under monitoring. That is, after remote phase synchronization, the phase difference between the target surge arrester voltage signal U∠90° and the capacitive current signal is 90°, and the target surge arrester voltage signal U∠90° is in phase with the resistive current signal. The surge arrester voltage value corresponding to the target surge arrester voltage signal is adjusted by a factor. The adjusted surge arrester voltage value is subtracted from the leakage current value corresponding to the leakage current signal. The result is then orthogonally calculated by the surge arrester voltage value and the subtraction result to obtain the effective values ​​of the resistive and capacitive currents. Specifically, as shown... Figure 4 As shown, In the formula, I, I C I R These are the RMS values ​​of the total current, capacitive current, and resistive current, respectively, from which the RMS value of the total current is obtained.

[0100] Optionally, step S22 may also include the following steps S221-S227:

[0101] S221. Adjust the surge arrester voltage value according to the preset multiple to obtain the target surge arrester voltage value;

[0102] S222. Subtract the voltage value of the target surge arrester from the leakage current value to obtain the target leakage current value.

[0103] S223. Perform orthogonal calculations on the surge arrester voltage value and the target leakage current value to obtain orthogonal results;

[0104] S224. Determine whether the orthogonal result is the target threshold;

[0105] S225. If the orthogonal result is not the target threshold, then proceed to the step of adjusting the surge arrester voltage value according to the preset multiple to obtain the target surge arrester voltage value.

[0106] S226. If the orthogonal result is the target threshold, then the target leakage current value is determined as the resistive current value, and the target surge arrester voltage value is determined as the capacitive current value.

[0107] S227. Generate the corresponding effective values ​​of resistive current and capacitive current according to the resistive current value and the capacitive current value.

[0108] It should be noted that the surge arrester voltage value is adjusted according to a preset multiple. Preferably, the surge arrester voltage value can be increased by K times or decreased by K times. The specific preset multiple can be adjusted according to the actual situation and is not limited here. The orthogonality result of the resistive current value and the surge arrester voltage value is 0, so the target threshold is 0.

[0109] In a specific embodiment, such as Figure 3 As shown, after adjusting the surge arrester voltage value by a factor of K, the target surge arrester voltage value KU∠90° is obtained. The target surge arrester voltage value KU∠90° and the leakage current value I are subtracted by a subtractor, KU∠90°-I, to obtain the target leakage current value. Specifically, the target leakage current value is the difference between the capacitive current and the resistive current, or only the resistive current.

[0110] The target leakage current value and the surge arrester voltage value are orthogonally multiplied. The result of the orthogonal operation is used to determine if there is any remaining capacitive current value after subtraction. If the orthogonal result is not zero, the process of adjusting the surge arrester voltage value by a factor of K and then subtracting the target surge arrester voltage value from the target leakage current value is repeated until the orthogonal result of the surge arrester voltage value and the target leakage current value is zero. When the orthogonal result is zero, it means that the subtractor has subtracted all the capacitive current value, leaving only the resistive current value. This indicates that the target leakage current value is determined to be a resistive current value, and the target surge arrester voltage value is determined to be a capacitive current value.

[0111] The effective value of the resistive current is obtained by dividing the analog resistive current signal corresponding to the resistive current value, low-pass filtering it, and then converting it into a digital resistive current signal by an analog-to-digital converter (ADC). Similarly, the effective value of the capacitive current is obtained by dividing the analog capacitive current signal corresponding to the capacitive current value, low-pass filtering it, and then converting it into a digital capacitive current signal by an ADC.

[0112] Step 206: Based on the ratio between the effective value of resistive current and the effective value of total current, obtain the insulation performance level and operational risk level of the zinc oxide surge arrester to be monitored.

[0113] Optionally, step 206 may also include the following steps S31-S34:

[0114] S31. Calculate the ratio between the effective value of the resistive current and the effective value of the total current;

[0115] S32. Match the corresponding performance level and risk level from the preset key value table according to the risk threshold range in which the ratio is located;

[0116] S33. The performance level is determined to be the insulation performance level corresponding to the zinc oxide surge arrester to be monitored;

[0117] S34. Determine the risk level as the operational risk level corresponding to the zinc oxide surge arrester to be monitored.

[0118] It should be noted that the preset key-value table is as shown in Table 1 below:

[0119] Percentage (%) Insulation performance class Operational risk level 0～10 excellent No abnormalities 10～20 middle There may be an anomaly. 20～30 Difference Mild abnormality

[0120] Table 1

[0121] In a specific embodiment, the ratio between the effective value of resistive current and the effective value of total current is calculated to obtain the percentage of the effective value of resistive current to the effective value of total current. Table 1 shows the performance level and risk level corresponding to the risk threshold range of the ratio. When the percentage is within 10%, it indicates that the insulation performance level of the zinc oxide surge arrester under monitoring is excellent, and the operation risk level shows no abnormality. When the percentage is within 20%, it indicates that the insulation performance level of the zinc oxide surge arrester under monitoring is medium, and the operation risk level shows that there may be an abnormality, requiring close attention from operators. It can be determined whether an investigation is needed based on the actual situation. When the percentage reaches 20-30%, it indicates that the insulation performance level of the zinc oxide surge arrester under monitoring is poor, and the operation risk level shows a slight abnormality. Once a slight abnormality is reached, it is necessary to investigate the zinc oxide surge arrester under monitoring and make corresponding handling plans based on the investigation results.

[0122] This invention receives the initial arrester voltage signal and leakage current signal of the zinc oxide surge arrester under monitoring in real time. It analyzes the phase of the initial arrester voltage signal and performs remote phase synchronization until the phase of the initial arrester voltage signal is in the same phase as the preset operating signal of the zinc oxide surge arrester under monitoring, generating an intermediate arrester voltage signal. Based on the arrester voltage value corresponding to the intermediate arrester voltage signal and the leakage current value corresponding to the leakage current signal, it determines the effective value of the resistive current and the effective value of the total current. The ratio between the effective value of the resistive current and the effective value of the total current is calculated to obtain the insulation performance level and operational risk level of the zinc oxide surge arrester under monitoring. This invention solves the technical problem of existing online monitoring systems that analyze voltage and leakage current remotely. However, the voltage and current obtained in the above methods are not in the same location, requiring long-distance wiring, which can easily cause secondary short circuits in the voltage transformer, leading to safety hazards. This invention enables real-time wireless monitoring of the operating status of each zinc oxide surge arrester, allowing for timely assessment of the insulation performance level and operational risk level of the zinc oxide surge arrester without power interruption. This allows for early prediction of potential faults and the development of corresponding solutions based on the predicted results.

[0123] Please see Figures 3-5 , Figure 5 This is a structural block diagram of a wireless monitoring system for zinc oxide surge arresters provided in an embodiment of the present invention.

[0124] This invention provides a wireless monitoring system for zinc oxide surge arresters, the system comprising:

[0125] The surge arrester voltage acquisition module 501 is used to receive the initial surge arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored in real time.

[0126] The first surge arrester voltage synchronization module 502 is used to remotely synchronize the initial surge arrester voltage signal to obtain an intermediate surge arrester voltage signal that is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored.

[0127] The surge arrester full current analysis module 503 is used to determine the effective value of resistive current and the effective value of full current based on the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal.

[0128] The second surge arrester voltage synchronization module 504 is used to obtain the insulation performance level and operating risk level of the zinc oxide surge arrester to be monitored based on the ratio between the effective value of resistive current and the effective value of total current.

[0129] Optionally, the surge arrester voltage acquisition module 501 may include:

[0130] The initial surge arrester voltage signal submodule is used to collect the initial surge arrester voltage signal in real time from the bus or line corresponding to the zinc oxide surge arrester to be monitored through a voltage transformer.

[0131] The leakage current signal submodule is used to acquire leakage current signals from the zinc oxide surge arrester under monitoring in real time.

[0132] The wireless communication submodule is used to receive the initial arrester voltage signal and leakage current signal of the zinc oxide arrester to be monitored in real time through the wireless communication unit.

[0133] Optionally, the first surge arrester voltage synchronization module 502 may include:

[0134] The voltage zero-crossing time submodule is used to perform low-pass filtering, DA conversion, and GPS timing on the initial surge arrester voltage signal to obtain the voltage zero-crossing time of the initial surge arrester voltage signal.

[0135] The phase angle submodule is used to determine the phase angle based on the zero-crossing time difference between the voltage zero-crossing time and the zero-crossing time of the preset operating voltage signal corresponding to the zinc oxide arrester to be monitored;

[0136] The intermediate surge arrester voltage submodule is used to remotely synchronize the initial surge arrester voltage according to the phase angle, so as to obtain an intermediate surge arrester voltage that is in the same phase as the operating voltage.

[0137] Optionally, the surge arrester full current analysis module 503 may include:

[0138] The target surge arrester voltage signal submodule is used to phase-shift the intermediate surge arrester voltage signal until it is in the same phase as the capacitive current signal corresponding to the leakage current signal, so as to obtain the target surge arrester voltage signal.

[0139] The effective value determination submodule is used to determine the effective values ​​of resistive current and capacitive current based on the arrester voltage value corresponding to the target arrester voltage signal and the leakage current value corresponding to the leakage current signal.

[0140] The total current RMS value submodule is used to calculate the arithmetic square root of the sum of squares between the RMS values ​​of resistive and capacitive currents to obtain the total current RMS value.

[0141] Optionally, the submodule for determining valid values ​​may also include:

[0142] The target surge arrester voltage value submodule is used to adjust the surge arrester voltage value according to a preset multiple to obtain the target surge arrester voltage value;

[0143] The target leakage current value submodule is used to subtract the target surge arrester voltage value from the leakage current value to obtain the target leakage current value.

[0144] The orthogonal results submodule is used to perform orthogonal calculations on the surge arrester voltage value and the target leakage current value to obtain orthogonal results.

[0145] The threshold determination submodule is used to determine whether the orthogonal result is the target threshold;

[0146] The jump execution submodule is used to jump to the step of adjusting the surge arrester voltage value by a preset multiple to obtain the target surge arrester voltage value if the orthogonal result is not the target threshold.

[0147] The capacitive current value submodule is used to determine the target leakage current value as a resistive current value and the target surge arrester voltage value as a capacitive current value if the orthogonal result is the target threshold.

[0148] The effective value generation submodule is used to generate the corresponding effective values ​​of resistive current and capacitive current based on the resistive current value and the capacitive current value.

[0149] Optionally, the second surge arrester voltage synchronization module 504 may further include:

[0150] The ratio calculation submodule is used to calculate the ratio between the effective value of the resistive current and the effective value of the total current;

[0151] The matching level submodule is used to match the corresponding performance level and risk level from a preset key-value table according to the risk threshold range in which the ratio is located;

[0152] The insulation performance level submodule is used to determine the performance level as the insulation performance level corresponding to the zinc oxide surge arrester to be monitored.

[0153] The risk level submodule is used to determine the risk level as the operational risk level corresponding to the zinc oxide surge arrester to be monitored.

[0154] In a specific embodiment, the first surge arrester voltage synchronization module and the second surge arrester voltage synchronization module can be the same physical surge arrester voltage synchronization module.

[0155] This invention receives the initial arrester voltage signal and leakage current signal of the zinc oxide surge arrester under monitoring in real time. It analyzes the phase of the initial arrester voltage signal and performs remote phase synchronization until the phase of the initial arrester voltage signal is in the same phase as the preset operating signal of the zinc oxide surge arrester under monitoring, generating an intermediate arrester voltage signal. Based on the arrester voltage value corresponding to the intermediate arrester voltage signal and the leakage current value corresponding to the leakage current signal, it determines the effective value of the resistive current and the effective value of the total current. The ratio between the effective value of the resistive current and the effective value of the total current is calculated to obtain the insulation performance level and operational risk level of the zinc oxide surge arrester under monitoring. This invention solves the technical problem of existing online monitoring systems that analyze voltage and leakage current remotely. However, the voltage and current obtained in the above methods are not in the same location, requiring long-distance wiring, which can easily cause secondary short circuits in the voltage transformer, leading to safety hazards. This invention enables real-time wireless monitoring of the operating status of each zinc oxide surge arrester, allowing for timely assessment of the insulation performance level and operational risk level of the zinc oxide surge arrester without power interruption. This allows for early prediction of potential faults and the development of corresponding solutions based on the predicted results.

[0156] This invention also provides an electronic device, which includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the processor performs the wireless monitoring method for zinc oxide surge arresters as described in any of the above embodiments.

[0157] This invention also provides a computer-readable storage medium storing a computer program, which, when executed, implements the wireless monitoring method for zinc oxide surge arresters as described in any embodiment of this invention.

[0158] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0159] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection between devices or units, and may be electrical, mechanical, or other forms.

[0160] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0161] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0162] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0163] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wireless monitoring method for zinc oxide surge arresters, characterized in that, The method includes: Real-time reception of the initial arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored; The initial surge arrester voltage signal is remotely phase synchronized to obtain an intermediate surge arrester voltage signal that is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored. Based on the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal, determine the effective value of the resistive current and the effective value of the total current. The insulation performance level and operational risk level of the zinc oxide surge arrester to be monitored are obtained based on the ratio between the effective value of the resistive current and the effective value of the total current.

2. The wireless monitoring method for zinc oxide surge arresters according to claim 1, characterized in that, The step of receiving the initial arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored in real time includes: The initial surge arrester voltage signal is collected in real time from the bus or line corresponding to the zinc oxide surge arrester to be monitored by a voltage transformer. Leakage current signals are collected in real time from the zinc oxide surge arrester to be monitored; The initial surge arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored are received in real time through the wireless communication unit.

3. The wireless monitoring method for zinc oxide surge arresters according to claim 1, characterized in that, The step of remotely synchronizing the initial surge arrester voltage signal to obtain an intermediate surge arrester voltage signal that is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored includes: The initial surge arrester voltage signal is subjected to low-pass filtering, DA conversion, and GPS timing to obtain the voltage zero-crossing time of the initial surge arrester voltage signal; The phase angle is determined based on the zero-crossing time difference between the voltage zero-crossing time and the zero-crossing time of the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored; The initial surge arrester voltage is remotely phase-synchronized according to the phase angle to obtain an intermediate surge arrester voltage that is in the same phase as the operating voltage.

4. The wireless monitoring method for zinc oxide surge arresters according to claim 1, characterized in that, The step of determining the effective value of resistive current and the effective value of total current based on the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal includes: The intermediate surge arrester voltage signal is phase-shifted until it is in the same phase as the capacitive current signal corresponding to the leakage current signal, thus obtaining the target surge arrester voltage signal. Based on the surge arrester voltage value corresponding to the target surge arrester voltage signal and the leakage current value corresponding to the leakage current signal, determine the effective value of resistive current and the effective value of capacitive current. The total effective current value is obtained by calculating the arithmetic square root of the sum of the squares of the effective values ​​of the resistive and capacitive currents.

5. The wireless monitoring method for zinc oxide surge arresters according to claim 4, characterized in that, The step of determining the effective values ​​of resistive current and capacitive current based on the surge arrester voltage value corresponding to the target surge arrester voltage signal and the leakage current value corresponding to the leakage current signal includes: The voltage value of the surge arrester is adjusted according to a preset multiple to obtain the target voltage value of the surge arrester. The target leakage current value is obtained by subtracting the target surge arrester voltage value from the leakage current value. The voltage value of the surge arrester and the target leakage current value are orthogonally calculated to obtain an orthogonal result; Determine whether the orthogonal result is the target threshold; If the orthogonal result is not the target threshold, then proceed to the step of adjusting the surge arrester voltage value by a preset multiple to obtain the target surge arrester voltage value; If the orthogonal result is the target threshold, then the target leakage current value is determined as a resistive current value, and the target surge arrester voltage value is determined as a capacitive current value; The corresponding effective values ​​of resistive current and capacitive current are generated according to the resistive current value and the capacitive current value.

6. The wireless monitoring method for zinc oxide surge arresters according to claim 5, characterized in that, The step of generating corresponding effective values ​​of resistive current and capacitive current according to the resistive current value and the capacitive current value includes: By acquiring the resistive current signal corresponding to the resistive current value; The resistive current signal is amplified, divided, and low-pass filtered to obtain the effective value of the resistive current corresponding to the resistive current signal. By acquiring the capacitive current signal corresponding to the capacitive current value; The capacitive current signal is amplified, divided, and low-pass filtered to obtain the effective value of the capacitive current corresponding to the capacitive current signal.

7. The wireless monitoring method for zinc oxide surge arresters according to claim 1, characterized in that, The step of obtaining the insulation performance and operational risk of the zinc oxide surge arrester to be monitored based on the ratio of the effective value of the resistive current to the effective value of the total current includes: Calculate the ratio between the effective value of the resistive current and the effective value of the total current; Match the corresponding performance level and risk level from the preset key value table according to the risk threshold range in which the ratio is located; The performance level is determined to be the insulation performance level corresponding to the zinc oxide surge arrester to be monitored; The risk level is determined as the operational risk level corresponding to the zinc oxide surge arrester to be monitored.

8. A wireless monitoring system for zinc oxide surge arresters, characterized in that, The system includes: The surge arrester voltage acquisition module is used to receive the initial surge arrester voltage signal and leakage current signal of the zinc oxide surge arrester to be monitored in real time; The first surge arrester voltage synchronization module is used to remotely synchronize the initial surge arrester voltage signal to obtain an intermediate surge arrester voltage signal that is in the same phase as the preset operating voltage signal corresponding to the zinc oxide surge arrester to be monitored. The surge arrester full current analysis module is used to determine the effective value of resistive current and the effective value of full current based on the surge arrester voltage value corresponding to the intermediate surge arrester voltage signal and the leakage current value corresponding to the leakage current signal. The second surge arrester voltage synchronization module is used to obtain the insulation performance level and operating risk level of the zinc oxide surge arrester to be monitored based on the ratio between the effective value of the resistive current and the effective value of the total current.

9. An electronic device, characterized in that, The device includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor causes the processor to perform the steps of the wireless monitoring method for zinc oxide surge arresters as described in any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed, it implements the wireless monitoring method for zinc oxide surge arresters as described in any one of claims 1-7.

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