A method and system for overvoltage protection of high-altitude mountain photovoltaic power stations

Abstract

The application provides a kind of overvoltage protection method and system for high altitude mountain photovoltaic station, the method comprises: real-time acquisition field area atmospheric electric field data and thunder signal, identify the invasion trend of thunderstorm and generate protection standby instruction;When lightning occurs, collect lightning current intensity and overvoltage amplitude parameter, match the corresponding working gear of four-stage discharge structure, conduct lightning energy through the layered conduction of step-by-step conduction discharge branch;Compare residual voltage value with preset safety threshold value, when residual voltage value exceeds preset safety threshold value, conduct auxiliary discharge branch to suppress residual overvoltage twice;According to the impedance parameter of potential distribution data dynamic adjustment each area grounding branch, balance the current distribution of global flow path;According to the operating parameter, generate device aging state evaluation result, and generate corresponding operation and maintenance early warning information.Overall, it can improve the comprehensiveness and reliability of lightning protection of high altitude mountain photovoltaic station, and ensure the long-term stable operation of station.

Description

Technical Field

[0001] This invention relates to the field of overvoltage protection technology for high-altitude mountain photovoltaic power stations, specifically to an overvoltage protection method and system for high-altitude mountain photovoltaic power stations. Background Technology

[0002] High-altitude mountainous areas are frequent sites of thunderstorm activity in my country. Compared to plains, these areas have lower cloud elevations, stronger electric fields to the ground, and higher lightning strike density, resulting in a particularly significant superimposed effect of lightning induction. Furthermore, the dramatic topography and complex geological structure of high-altitude mountainous regions, coupled with generally high soil resistivity, lead to uneven distribution of current dissipation paths in the grounding grid of photovoltaic (PV) power plants. Under lightning strike conditions, these plants are highly susceptible to localized potential concentration, causing excessive step voltage and contact voltage. This not only damages precision power electronic equipment such as PV modules, inverters, and combiner boxes but also seriously threatens the personal safety of maintenance personnel. Therefore, lightning protection for PV power plants in high-altitude mountainous areas is far more challenging than that for those in ordinary plains.

[0003] Currently, the lightning protection for high-altitude mountain photovoltaic power plants in the industry generally adopts a traditional fixed multi-stage surge protector combination protection scheme. This scheme has a simplistic overall technical approach, poor adaptability to various operating conditions, and is difficult to match the unique thunderstorm environment and complex terrain grounding conditions of high-altitude mountainous areas. This traditional scheme uses a simple multi-stage protection structure with fixed tap positions, relying on fixed action thresholds to discharge lightning. While it is currently the mainstream application technology for lightning protection of photovoltaic power plants, it has gradually revealed many inherent technical defects under complex high-altitude conditions, failing to meet the protection requirements for the long-term safe and stable operation of the power plants. Summary of the Invention

[0004] Based on this, and in response to the shortcomings of existing technologies, this invention provides an overvoltage protection method and system for high-altitude mountain photovoltaic power stations. This addresses the problems of existing high-altitude mountain photovoltaic lightning protection systems, such as chaotic hierarchical structure, insufficient current discharge capacity, lack of intelligent sensing, inability to predict device failures, uneven mountain potential, and excessive residual voltage leading to equipment breakdown, which result in the inability to meet the protection requirements for the long-term safe and stable operation of the power station.

[0005] To solve the above-mentioned technical problems, the first aspect of the present invention proposes: An overvoltage protection method for high-altitude mountain photovoltaic power stations, wherein the method includes: Real-time acquisition of atmospheric electric field data and lightning signals in the field area, identification of thunderstorm intrusion trends and generation of protection standby instructions, switching the system to the prevention and protection state and completing the preset discharge level; When a lightning strike occurs, the lightning current intensity and overvoltage amplitude parameters are collected, and the corresponding working position of the four-stage bleeder architecture is matched. The lightning energy is then conducted in layers through the bleeder branches that are connected in stages. The residual voltage values ​​at each level of protection are continuously collected and compared with the preset safety threshold. When the residual voltage value exceeds the preset safety threshold, the auxiliary discharge branch is activated to suppress the residual overvoltage for a second time. The potential distribution data of each branch of the grounding grid is collected synchronously, and the impedance parameters of each grounding branch in each area are dynamically adjusted according to the potential distribution data to balance the current distribution of the current dissipation path in the whole area. The system continuously collects the operating parameters of surge protection devices, generates device aging status assessment results based on the operating parameters, and generates corresponding operation and maintenance early warning information based on the assessment results.

[0006] The beneficial effects of this invention are as follows: This solution addresses the complex lightning conditions of high-altitude mountain photovoltaic power stations. Through a collaborative protection architecture of situational awareness, graded discharge, residual voltage suppression, potential balancing, and device monitoring, it effectively improves the shortcomings of traditional lightning protection systems, such as chaotic hierarchical coordination and insufficient discharge capacity. The four-level layered discharge architecture can adaptively match the working level according to the lightning strike intensity, covering the full intensity range from weak induced lightning to strong direct lightning, and realizing the orderly conduction of lightning energy step by step. Meanwhile, the forward-looking lightning situation awareness mechanism breaks through the limitations of traditional passive protection, enabling early prediction of lightning intrusion and pre-setting of protection measures, thus improving the system's response timeliness. The residual voltage closed-loop suppression mechanism can perform secondary clamping on residual overvoltages after each level of discharge, reducing the risk of power electronic equipment breakdown caused by excessive residual voltage. Mountain potential balancing control can dynamically adjust the impedance of grounding branches, improve the problem of local potential concentration caused by mountainous terrain, and reduce the potential difference across the entire area. Online device status monitoring can assess the aging degree of lightning protection devices in real time, identify potential failures in advance, and push early warnings, reducing the risk of devices operating with defects. Overall, it improves the comprehensiveness and reliability of lightning protection for high-altitude mountain photovoltaic power stations, ensuring the long-term stable operation of the stations.

[0007] Furthermore, the steps of real-time acquisition of atmospheric electric field data and lightning signals in the field area, identification of thunderstorm intrusion trends and generation of protection standby commands, switching the system to the prevention and protection state and completing the preset discharge level include: Atmospheric electric field intensity data at multiple points in the field area are collected using a distributed electric field sensor array, and lightning electromagnetic pulse signals are collected using a lightning detection antenna. Trend fitting analysis was performed on atmospheric electric field intensity data to extract the electric field change rate and amplitude characteristics; spectrum analysis was performed on lightning electromagnetic pulse signals to extract the lightning occurrence distance and intensity characteristics. The electric field change rate and amplitude characteristics are fused with the lightning distance and intensity characteristics to generate a thunderstorm intrusion risk level. Based on the risk level of thunderstorm intrusion, a corresponding level of protection standby command is generated, driving the bleedering architecture to complete the pre-switching preparation for the corresponding level.

[0008] Furthermore, when a lightning strike occurs, the steps of collecting lightning current intensity and overvoltage amplitude parameters, matching the corresponding operating level of the four-stage bleeder architecture, and conducting lightning energy in layers through the bleeder branches with progressively connected circuits include: The instantaneous value of the lightning current in the main circuit is collected by a current transformer, and the instantaneous value of the bus overvoltage is collected by a voltage sensor. The instantaneous value of the lightning current is compared with the preset four-level current threshold, and the instantaneous value of the overvoltage is compared with the preset four-level voltage threshold to determine the lightning energy level. According to the lightning strike energy level, the corresponding branch combinations in the first-level coarse discharge branch, the second-level fine discharge branch, the third-level fine discharge branch, and the fourth-level micro discharge branch are connected in sequence. Through the current-limiting elements and nonlinear varistor elements in each level of the discharge branch, lightning energy of different frequencies and amplitudes is distributed proportionally.

[0009] Furthermore, the step of sequentially activating the corresponding branch combinations in the first-stage coarse discharge branch, the second-stage fine discharge branch, the third-stage fine discharge branch, and the fourth-stage micro discharge branch according to the lightning strike energy level includes: When the lightning strike energy level reaches the first-level threshold, only the first-level coarse discharge branch is activated; When the lightning strike energy level reaches the second-level threshold, the first-level coarse discharge branch and the second-level fine discharge branch are simultaneously activated. When the lightning strike energy level reaches the third-level threshold, the first, second, and third-level discharge branches are simultaneously activated. When the lightning strike energy level reaches the fourth-level threshold, all fourth-level discharge branches are activated.

[0010] Furthermore, the step of continuously collecting residual voltage values ​​at each level of protection backend, comparing the residual voltage values ​​with a preset safety threshold, and when the residual voltage value exceeds the preset safety threshold, conducting the auxiliary bleed branch to perform secondary suppression of the residual overvoltage includes: Voltage sampling points are set at the rear end of each bleed branch to synchronously collect the residual voltage values ​​at the output terminals of each stage. The residual voltage value of each level is compared with the corresponding residual voltage safety threshold in real time. When the residual voltage value of any stage exceeds the corresponding safety threshold, the auxiliary suppression branch connected in parallel with the current discharge branch of that stage is turned on. The residual voltage exceeding the threshold is clamped and absorbed by the active clamping element in the auxiliary suppression branch until the residual voltage falls back to the safe threshold range.

[0011] Furthermore, the steps of synchronously acquiring potential distribution data of each branch of the grounding grid, dynamically adjusting the impedance parameters of each area's grounding branch based on the potential distribution data, and balancing the current distribution of the entire current dissipation path include: Potential acquisition points are set at different branch nodes of the grounding grid to collect the ground potential value of each node in real time. Calculate the difference between the ground potential values ​​of each node to generate a global potential distribution gradient map; Identify local areas where the potential gradient exceeds a preset threshold and locate high-potential concentrated branches; Adjusting the impedance value of the adjustable impedance element in the high-potential concentrated branch increases the current dissipation of the branch and reduces the local potential concentration.

[0012] Furthermore, the steps of continuously collecting the operating parameters of the surge protection devices, generating device aging status assessment results based on the operating parameters, and generating corresponding maintenance early warning information based on the assessment results include: Collect the leakage current value, surface temperature value, and cumulative number of operations of each surge protection device; The leakage current value is compared with the preset leakage current reference value, the surface temperature value is compared with the preset temperature reference value, and the device degradation score is generated by combining the cumulative value of the number of operations. When the device degradation score exceeds the preset warning threshold, a replacement warning message for the corresponding device is generated. Record the timing of each device's actions and energy tolerance data during each lightning strike to create a device operation history archive.

[0013] The second aspect of the present invention proposes: An overvoltage protection system for high-altitude mountain photovoltaic power stations, wherein the system comprises: The lightning situation awareness module is used to collect atmospheric electric field data and lightning signals in the field area in real time, identify the trend of thunderstorm intrusion and generate protection standby instructions, switch the system to the prevention and protection state and complete the preset of the discharge level. The graded discharge control module is used to collect lightning current intensity and overvoltage amplitude parameters when a lightning strike occurs, match the corresponding working position of the four-stage discharge architecture, and conduct lightning energy in layers through the discharge branches that are connected in stages. The residual voltage closed-loop suppression module is used to continuously collect the residual voltage values ​​at each level of protection backend, compare the residual voltage values ​​with the preset safety threshold, and when the residual voltage value exceeds the preset safety threshold, the auxiliary discharge branch is activated to suppress the residual overvoltage for a second time. The potential equalization control module is used to synchronously collect the potential distribution data of each branch of the grounding grid, and dynamically adjust the impedance parameters of each area's grounding branch according to the potential distribution data to equalize the current distribution of the entire current dissipation path. The device status monitoring module is used to continuously collect the operating parameters of the surge protection device, generate device aging status assessment results based on the operating parameters, and generate corresponding operation and maintenance early warning information based on the assessment results.

[0014] Furthermore, the lightning situation awareness module is specifically used for: Atmospheric electric field intensity data at multiple points in the field area are collected using a distributed electric field sensor array, and lightning electromagnetic pulse signals are collected using a lightning detection antenna. Trend fitting analysis was performed on atmospheric electric field intensity data to extract the electric field change rate and amplitude characteristics; spectrum analysis was performed on lightning electromagnetic pulse signals to extract the lightning occurrence distance and intensity characteristics. The electric field change rate and amplitude characteristics are fused with the lightning distance and intensity characteristics to generate a thunderstorm intrusion risk level. Based on the risk level of thunderstorm intrusion, a corresponding level of protection standby command is generated, driving the bleedering architecture to complete the pre-switching preparation for the corresponding level.

[0015] Furthermore, the tiered discharge control module is specifically used for: The instantaneous value of the lightning current in the main circuit is collected by a current transformer, and the instantaneous value of the bus overvoltage is collected by a voltage sensor. The instantaneous value of the lightning current is compared with the preset four-level current threshold, and the instantaneous value of the overvoltage is compared with the preset four-level voltage threshold to determine the lightning energy level. According to the lightning strike energy level, the corresponding branch combinations in the first-level coarse discharge branch, the second-level fine discharge branch, the third-level fine discharge branch, and the fourth-level micro discharge branch are connected in sequence. Through the current-limiting elements and nonlinear varistor elements in each level of the discharge branch, lightning energy of different frequencies and amplitudes is distributed proportionally.

[0016] Furthermore, the tiered discharge control module is specifically used for: When the lightning strike energy level reaches the first-level threshold, only the first-level coarse discharge branch is activated; When the lightning strike energy level reaches the second-level threshold, the first-level coarse discharge branch and the second-level fine discharge branch are simultaneously activated. When the lightning strike energy level reaches the third-level threshold, the first, second, and third-level discharge branches are simultaneously activated. When the lightning strike energy level reaches the fourth-level threshold, all fourth-level discharge branches are activated.

[0017] Furthermore, the residual pressure closed-loop suppression module is specifically used for: Voltage sampling points are set at the rear end of each bleed branch to synchronously collect the residual voltage values ​​at the output terminals of each stage. The residual voltage value of each level is compared with the corresponding residual voltage safety threshold in real time. When the residual voltage value of any stage exceeds the corresponding safety threshold, the auxiliary suppression branch connected in parallel with the current discharge branch of that stage is turned on. The residual voltage exceeding the threshold is clamped and absorbed by the active clamping element in the auxiliary suppression branch until the residual voltage falls back to the safe threshold range.

[0018] Furthermore, the potential equalization control module is specifically used for: Potential acquisition points are set at different branch nodes of the grounding grid to collect the ground potential value of each node in real time. Calculate the difference between the ground potential values ​​of each node to generate a global potential distribution gradient map; Identify local areas where the potential gradient exceeds a preset threshold and locate high-potential concentrated branches; Adjusting the impedance value of the adjustable impedance element in the high-potential concentrated branch increases the current dissipation of the branch and reduces the local potential concentration.

[0019] Furthermore, the device status monitoring module is specifically used for: Collect the leakage current value, surface temperature value, and cumulative number of operations of each surge protection device; The leakage current value is compared with the preset leakage current reference value, the surface temperature value is compared with the preset temperature reference value, and the device degradation score is generated by combining the cumulative value of the number of operations. When the device degradation score exceeds the preset warning threshold, a replacement warning message for the corresponding device is generated. Record the timing of each device's actions and energy tolerance data during each lightning strike to create a device operation history archive.

[0020] The third aspect of the present invention proposes: A computer includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the overvoltage protection method for high-altitude mountain photovoltaic power stations as described above.

[0021] The fourth aspect of the present invention proposes: A readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the overvoltage protection method for high-altitude mountain photovoltaic power stations as described above. Attached Figure Description

[0022] Figure 1 A flowchart of an overvoltage protection method for a high-altitude mountain photovoltaic power station provided in the first embodiment of the present invention; Figure 2 This is a structural block diagram of an overvoltage protection system for high-altitude mountain photovoltaic power stations provided in the third embodiment of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0024] Please see Figure 1 The first embodiment of the present invention provides an overvoltage protection method for photovoltaic power stations in high-altitude mountainous areas. The method adopts a closed-loop protection logic integrating situation prediction, graded current discharge, residual voltage suppression, potential balancing and status monitoring. It achieves intelligent lightning protection for all operating conditions and the entire link, especially for special working conditions such as high intensity of thunderstorms, complex terrain and uneven soil resistivity in high-altitude mountainous areas.

[0025] Specifically, the first embodiment of the present invention provides: An overvoltage protection method for high-altitude mountain photovoltaic power stations, wherein the method includes: Step S10: Collect atmospheric electric field data and lightning signals in the field area in real time, identify the trend of thunderstorm intrusion and generate protection standby instructions, switch the system to the prevention and protection state and complete the preset of the discharge level. It should be noted that this step, by real-time monitoring of the atmospheric electric field and lightning signals in the photovoltaic power station area, identifies lightning intrusion trends in advance and adjusts the system to a standby state. Simultaneously, it pre-configures the discharge levels, solving the problem of traditional lightning protection systems being completely passive and lagging in response. Specifically, high-precision lightning electric field sensors, lightning strike counting sensors, and high-speed AC / DC overvoltage sampling units are distributed throughout the photovoltaic power station area, covering key nodes such as photovoltaic module arrays, string branches, combiner boxes, inverters, and grid-connected cabinets. This allows for 24-hour real-time monitoring of key parameters such as atmospheric electric field intensity, lightning movement, lightning strike frequency, instantaneous lightning current amplitude, surge overvoltage waveform, and voltage rise rate. At the same time, a high-altitude lightning characteristic database is established, combined with the activity patterns of thunderstorms on the plateau, to achieve early prediction of lightning intrusion. This provides accurate data support for the adaptive switching and pre-regulation of the downstream tiered discharge levels, completely changing the shortcomings of traditional passive lightning protection.

[0026] Step S20: Collect lightning current intensity and overvoltage amplitude parameters, match the corresponding working position of the four-stage bleeder architecture, and conduct lightning energy in layers through the bleeder branches that are connected in stages. It is worth noting that the four-level discharge architecture, with its matching and progressive conduction, effectively conducts and dissipates lightning energy of varying intensities in a layered manner, overcoming the shortcomings of traditional two-level fixed lightning protection architectures, such as chaotic hierarchical structure and insufficient discharge capacity. Specifically, in a four-level layered protection system adapted to high-altitude severe thunderstorm conditions—component-side pre-discharge, string-level buffer discharge, combiner box main discharge, and grid-connection point final clamping—each level of protection is precisely coordinated, with differentiated action timing. The discharge level can adaptively switch according to the real-time lightning intensity. For weak induced lightning strikes during cloudy or overcast weather, a low-level precise clamping mode is activated to avoid power loss and equipment malfunctions caused by over-protection. For direct lightning strikes and superimposed impacts of strong induced lightning strikes during thunderstorms, a full-channel high-current discharge mode is automatically activated, progressively diverting and reducing voltage to dissipate lightning energy in a layered manner. This completely solves the problems of insufficient discharge capacity, chaotic hierarchy, and large protection blind spots in traditional lightning protection systems, achieving efficient discharge of lightning energy of all intensities.

[0027] Step S30: Continuously collect the residual voltage values ​​at each level of protection backend, compare the residual voltage values ​​with the preset safety threshold, and when the residual voltage value exceeds the preset safety threshold, conduct the auxiliary discharge branch to suppress the residual overvoltage for a second time. It should be noted that this step is a residual voltage closed-loop suppression, which is executed synchronously with the tiered discharge. By monitoring the residual voltage at the downstream end of each discharge stage in real time, it performs secondary suppression of excessive residual voltage, ensuring that the downstream equipment is always within a safe voltage range. This fills the technical gap in traditional lightning protection that only discharges but does not control residual voltage. Specifically, a residual voltage closed-loop feedback control unit is added at the downstream end of the four-stage discharge architecture. This unit samples the residual voltage values ​​and voltage fluctuation waveforms at the downstream end of each lightning protection device in real time at high speed, establishing a closed-loop judgment logic for the residual voltage threshold. When the lightning strike residual voltage is detected to be close to or exceed the safe tolerance threshold of the photovoltaic equipment, the system instantly activates the auxiliary flexible discharge branch, dynamically optimizes the loop impedance, and quickly dissipates the residual overvoltage, strictly limiting the lightning strike residual voltage of the entire station within the safe range of the equipment. This fundamentally prevents the breakdown and damage of inverter IGBTs, module chips, and communication ports caused by excessive residual voltage, filling the technical gap of precise residual voltage suppression in high-altitude photovoltaic lightning protection.

[0028] Step S40: Synchronously collect the potential distribution data of each branch of the grounding grid, and dynamically adjust the impedance parameters of each area's grounding branch according to the potential distribution data to balance the current distribution of the entire current dissipation path.

[0029] It should be noted that this step is performed simultaneously with the lightning strike. By dynamically adjusting the impedance parameters of each grounding branch, the overall current dissipation effect under complex mountainous terrain is balanced, eliminating local potential concentration and reducing the risk of excessive step voltage and contact voltage. For high-altitude mountainous terrain with undulating terrain, uneven soil, and large differences in grounding current dissipation, the traditional fixed impedance grounding structure is abandoned in favor of a dynamically adjustable grounding branch design. Based on the grounding current dissipation data and ground potential gradient distribution in each area at the moment of lightning strike, the conduction impedance of each grounding branch is dynamically adjusted to balance the grounding current dissipation velocity and discharge capacity across the entire station, eliminating local potential concentration and excessive ground potential difference. This effectively suppresses excessive step voltage and contact voltage during lightning strikes, achieving equipotential protection across the entire mountainous photovoltaic station and significantly improving the uniformity and safety of lightning protection under complex terrain.

[0030] Step S50: Continuously collect the operating parameters of the surge protection device, generate the device aging status assessment result based on the operating parameters, and generate corresponding operation and maintenance early warning information based on the assessment result.

[0031] It's worth noting that by continuously collecting device operating parameters to assess aging status, potential failures can be identified in advance, and maintenance warnings can be pushed out, upgrading the maintenance model from reactive emergency repairs to proactive predictive maintenance. Addressing the pain points of easily aging, failing, and thermally breaking down surge protection devices in high-altitude areas, an online monitoring system covering the entire lifecycle of surge protection devices has been established. This system collects leakage current, static residual voltage, dynamic response time, casing temperature, and thermal stability parameters of surge protectors at all levels in real time. Big data algorithms determine the degree of device aging, degradation trends, and failure risks in real time, distinguishing between three fault levels: slight aging, severe degradation, and complete failure. Through dual warnings via a cloud platform and local terminals, it accurately prompts maintenance personnel to replace failed devices at designated locations, eliminating the need for manual disassembly and point-by-point inspection. This upgrades the surge protection system from "post-failure emergency repairs" to "pre-failure predictive maintenance," eliminating the potential for surge protection devices to operate with defects.

[0032] Second Embodiment Furthermore, the steps of real-time acquisition of atmospheric electric field data and lightning signals in the field area, identification of thunderstorm intrusion trends and generation of protection standby commands, switching the system to the prevention and protection state and completing the preset discharge level include: Atmospheric electric field intensity data at multiple points in the field area are collected using a distributed electric field sensor array, and lightning electromagnetic pulse signals are collected using a lightning detection antenna. Trend fitting analysis was performed on atmospheric electric field intensity data to extract the electric field change rate and amplitude characteristics; spectrum analysis was performed on lightning electromagnetic pulse signals to extract the lightning occurrence distance and intensity characteristics. The electric field change rate and amplitude characteristics are fused with the lightning distance and intensity characteristics to generate a thunderstorm intrusion risk level. Based on the risk level of thunderstorm intrusion, a corresponding level of protection standby command is generated, driving the bleedering architecture to complete the pre-switching preparation for the corresponding level.

[0033] It should be noted that a sensing network is formed by a distributed array of electric field sensors and a lightning detection antenna. The distributed electric field sensor array is deployed in a grid pattern across the photovoltaic power station area, covering key areas such as the module array, combiner box area, and inverter room. It simultaneously collects atmospheric electric field intensity data from multiple points, eliminating monitoring blind spots caused by local terrain obstruction. The lightning detection antenna is a broadband electromagnetic pulse receiving antenna used to capture electromagnetic radiation signals generated by lightning discharges. Feature parameters are extracted, and algorithms are applied to the two types of raw data: time series trend fitting is performed on the atmospheric electric field intensity data to calculate the rate of change of the electric field and the instantaneous amplitude; these two parameters reflect the approach speed and charge intensity of thunderstorm clouds. Fourier spectrum analysis is performed on the lightning electromagnetic pulse signal, and the distance and intensity of the lightning strike are calculated by combining the signal propagation attenuation model, enabling a preliminary determination of the lightning strike location and energy. Risk level fusion calculation is performed by fusing multi-dimensional data of electric field change characteristics and lightning distance characteristics. A weighted scoring model is used to generate a lightning intrusion risk level, typically divided into four levels: low risk, medium risk, high risk, and extremely high risk. Fusion calculation avoids misjudgment from a single data source and improves prediction accuracy. The fourth step is the generation of protection preset commands. Based on different risk levels, corresponding standby commands are output to drive the switching elements of the current-discharge architecture to complete pre-charging and level pre-switching. A large current-discharge level is preset for high-risk levels, and a small current-discharge level is preset for low-risk levels, ensuring the system can respond instantly and shorten action delays when a lightning strike occurs.

[0034] Furthermore, when a lightning strike occurs, the steps of collecting lightning current intensity and overvoltage amplitude parameters, matching the corresponding operating level of the four-stage bleeder architecture, and conducting lightning energy in layers through the bleeder branches with progressively connected current include: The instantaneous value of the lightning current in the main circuit is collected by a current transformer, and the instantaneous value of the bus overvoltage is collected by a voltage sensor. The instantaneous value of the lightning current is compared with the preset four-level current threshold, and the instantaneous value of the overvoltage is compared with the preset four-level voltage threshold to determine the lightning energy level. According to the lightning strike energy level, the corresponding branch combinations in the first-level coarse discharge branch, the second-level fine discharge branch, the third-level fine discharge branch, and the fourth-level micro discharge branch are connected in sequence. Through the current-limiting elements and nonlinear varistor elements in each level of the discharge branch, lightning energy of different frequencies and amplitudes is distributed proportionally.

[0035] It should be noted that a high-precision current transformer is connected in series with the main circuit to collect the instantaneous current value at the moment of lightning strike, with a sampling frequency of no less than megahertz, to capture the steep leading edge of the lightning current. A high-voltage sensor is connected in parallel with the bus side to collect the instantaneous amplitude and waveform of the overvoltage, providing a two-dimensional basis for subsequent level determination. For lightning strike energy level determination, four current thresholds and four voltage thresholds are preset to form a two-dimensional determination matrix. The measured current and voltage values ​​are compared with the corresponding thresholds, and the higher of the two determinations is taken as the final lightning strike energy level, avoiding mismatch caused by relying on a single parameter. The four-level branch combinations are activated, with the first-level coarse current branch, the second-level fine current branch, the third-level fine current branch, and the fourth-level micro current branch set in descending order of energy. The corresponding number of branch combinations are activated according to the determined lightning strike energy level; the higher the energy level, the more branches are activated, and the greater the total leakage current. Layered energy dissipation is implemented, with current-limiting elements and nonlinear varistor elements configured within each branch. The coarse current discharge branch uses a large-current graphite gap element to handle most of the high current discharge; the fine current discharge branch and the micro current discharge branch use metal oxide varistors to absorb mid-frequency energy; and the micro current discharge branch uses transient suppression diodes to clamp residual peak voltages. The components at each level cooperate according to frequency band and amplitude to achieve layered and orderly dissipation of lightning strike energy.

[0036] Furthermore, the step of sequentially activating the corresponding branch combinations in the first-stage coarse discharge branch, the second-stage fine discharge branch, the third-stage fine discharge branch, and the fourth-stage micro discharge branch according to the lightning strike energy level includes: When the lightning strike energy level reaches the first-level threshold, only the first-level coarse discharge branch is activated; When the lightning strike energy level reaches the second-level threshold, the first-level coarse discharge branch and the second-level fine discharge branch are simultaneously activated. When the lightning strike energy level reaches the third-level threshold, the first, second, and third-level discharge branches are simultaneously activated. When the lightning strike energy level reaches the fourth-level threshold, all fourth-level discharge branches are activated.

[0037] It should be noted that when the lightning energy level only reaches the first-level threshold, it is determined to be a weak induced lightning condition. In this case, only the first-level coarse current discharge branch needs to be activated to complete the energy discharge, while the other branches remain disconnected. This mode has a small discharge current and low operating loss, which can avoid power loss and equipment malfunction caused by over-protection. It is suitable for weak induced lightning scenarios in cloudy or overcast weather. When the lightning energy level reaches the second-level threshold, it is determined to be a medium induced lightning condition. At the same time, the first-level coarse current discharge branch and the second-level fine current discharge branch are activated. The two branches work together. The coarse current discharge branch undertakes the main current discharge, and the fine current discharge branch performs secondary voltage reduction on the remaining voltage, forming a two-stage voltage reduction structure. When the lightning energy level reaches the third-level threshold, it is determined to be a strong induced lightning condition. At the same time, the first three discharge branches are activated. On the basis of the two-stage voltage reduction, a third-level fine current discharge branch is added to further refine the energy stratification and reduce the energy carrying pressure of each stage. When the lightning strike energy level reaches the fourth-level threshold, it is determined to be a direct lightning strike or a superposition of strong induced lightning. All four-level discharge branches are activated, forming a full-channel high-current discharge mode. The four-level branches progressively shunt and reduce voltage, maximizing the total discharge capacity and ensuring that the strong lightning strike energy can be fully dissipated, avoiding overload damage to single-level branches. This progressively advancing activation logic can achieve adaptive matching across the entire range of lightning strike intensities, solving the problem of poor adaptability to varying lightning strike strengths in traditional fixed-level lightning protection systems.

[0038] Furthermore, the step of continuously collecting residual voltage values ​​at each level of protection backend, comparing the residual voltage values ​​with a preset safety threshold, and when the residual voltage value exceeds the preset safety threshold, conducting the auxiliary bleed branch to perform secondary suppression of the residual overvoltage includes: Voltage sampling points are set at the rear end of each bleed branch to synchronously collect the residual voltage values ​​at the output terminals of each stage. The residual voltage value of each level is compared with the corresponding residual voltage safety threshold in real time. When the residual voltage value of any stage exceeds the corresponding safety threshold, the auxiliary suppression branch connected in parallel with the current discharge branch of that stage is turned on. The residual voltage exceeding the threshold is clamped and absorbed by the active clamping element in the auxiliary suppression branch until the residual voltage falls back to the safe threshold range.

[0039] It should be noted that an independent high-speed voltage sampling point is set at the output end of each leakage branch, with the sampling frequency matching the lightning waveform frequency to ensure the capture of nanosecond-level residual voltage spikes. Each sampling point is triggered and collected synchronously to ensure data timing consistency. Furthermore, a corresponding residual voltage safety threshold is preset for each leakage branch. This threshold is determined based on the voltage tolerance level of the downstream connected equipment; the closer the branch is to the downstream equipment, the stricter the residual voltage safety threshold setting. The real-time collected residual voltage values ​​at each stage are continuously compared with the corresponding thresholds. If the value approaches or exceeds the threshold, subsequent actions are immediately triggered. The auxiliary branch is activated. When any stage detects an excessive residual voltage, the auxiliary suppression branch connected in parallel with the main leakage branch at that stage is instantaneously activated. The auxiliary branch uses an independent fast-switching element, with the activation time controlled at the nanosecond level to ensure timely response to residual voltage spikes. The auxiliary suppression branch is equipped with an active clamping element that dynamically adjusts its own impedance to clamp and absorb excessive residual voltage, suppressing the residual overvoltage to below the safe threshold. Once the residual voltage stabilizes and falls back within a safe range, the auxiliary branch automatically disconnects, restoring normal operation. This closed-loop suppression mechanism can perform secondary regulation of the residual voltage after current leakage, fundamentally reducing the risk of downstream power electronic equipment being damaged by residual voltage.

[0040] Furthermore, the steps of synchronously acquiring potential distribution data of each branch of the grounding grid, dynamically adjusting the impedance parameters of each area's grounding branch based on the potential distribution data, and balancing the current distribution of the entire current dissipation path include: Potential acquisition points are set at different branch nodes of the grounding grid to collect the ground potential value of each node in real time. Calculate the difference between the ground potential values ​​of each node to generate a global potential distribution gradient map; Identify local areas where the potential gradient exceeds a preset threshold and locate high-potential concentrated branches; Adjusting the impedance value of the adjustable impedance element in the high-potential concentrated branch increases the current dissipation of the branch and reduces the local potential concentration.

[0041] It should be noted that potential acquisition electrodes are deployed at various branch nodes of the grounding grid, covering areas with different altitudes and soil types within the site. Real-time acquisition of ground potential values ​​at each node provides multi-point baseline data for global potential analysis. The second step is potential gradient calculation. Based on the spatial location and corresponding potential values ​​of each node, a spatial interpolation algorithm is used to calculate the potential distribution across the entire site, generating a global potential gradient map. This gradient map visually presents the potential differences between regions and clearly identifies areas of potential abrupt changes. The third step is high-potential area identification. A preset potential gradient safety threshold is used. The potential difference values ​​of each region in the gradient map are compared with the threshold to identify local areas where the potential gradient exceeds the threshold. The corresponding grounding branch is then identified as a high-potential concentrated branch. These branches are typically located in mountainous areas with high soil resistivity and poor current dissipation conditions. The fourth step is dynamic impedance adjustment. An adjustable impedance element is connected in series in the high-potential concentrated branch. After identifying local potential concentration, the resistance value of the adjustable impedance element is adjusted to reduce the total impedance of the branch, thereby increasing the current dissipation of the branch and guiding more lightning current to the ground through the branch. This gradually lowers the local area's ground potential, reduces the potential difference with the surrounding area, and ultimately achieves a balanced current distribution across the entire current dissipation path. This dynamic adjustment mechanism can effectively improve the current dissipation differences caused by undulating mountainous terrain and uneven soil, and suppress excessive step voltage and contact voltage caused by local potential rise.

[0042] Furthermore, the steps of continuously collecting the operating parameters of the surge protection devices, generating device aging status assessment results based on the operating parameters, and generating corresponding maintenance early warning information based on the assessment results include: Collect the leakage current value, surface temperature value, and cumulative number of operations of each surge protection device; The leakage current value is compared with the preset leakage current reference value, the surface temperature value is compared with the preset temperature reference value, and the device degradation score is generated by combining the cumulative value of the number of operations. When the device degradation score exceeds the preset warning threshold, a replacement warning message for the corresponding device is generated. Record the timing of each device's actions and energy tolerance data during each lightning strike to create a device operation history archive.

[0043] It should be noted that for surge protectors and other lightning protection devices at all levels, three core parameters are collected: leakage current, surface temperature, and number of trips. Leakage current reflects the degree of internal insulation degradation, surface temperature reflects the thermal stability, and the number of trips reflects the cumulative energy tolerance. These three parameters comprehensively characterize the device's health status. A degradation score is calculated by pre-setting benchmark values ​​for leakage current and temperature. The deviations between the measured leakage current and temperature values ​​are calculated, and then weighted and summed with the cumulative number of trips to generate a degradation score ranging from 0 to 100. Higher scores indicate more severe degradation. A tiered early warning system is generated with preset thresholds. When the device degradation score exceeds the threshold, a replacement warning is generated for the corresponding device. This warning includes the device location number, degradation level, and recommended replacement cycle, and can be directly pushed to maintenance personnel's terminals to guide targeted replacement. An operational record is established, automatically recording data such as the action sequence, peak withstand current, and energy absorption of each device after each lightning strike, forming a complete lifecycle operational history record for each device. This record data can be used to retrospectively analyze device degradation patterns, providing data support for subsequent threshold optimization and device selection. This full lifecycle monitoring mechanism can promptly identify aging and failing lightning protection devices, avoiding the risk of protection failure due to faulty devices operating.

[0044] Please see Figure 2 The third embodiment of the present invention provides: An overvoltage protection system for high-altitude mountain photovoltaic power stations, wherein the system comprises: The lightning situation awareness module is used to collect atmospheric electric field data and lightning signals in the field area in real time, identify the trend of thunderstorm intrusion and generate protection standby instructions, switch the system to the prevention and protection state and complete the preset of the discharge level. The graded discharge control module is used to collect lightning current intensity and overvoltage amplitude parameters when a lightning strike occurs, match the corresponding working level of the four-stage discharge architecture, and conduct lightning energy in layers through the discharge branches that are connected in stages. The residual voltage closed-loop suppression module is used to continuously collect the residual voltage values ​​at each level of protection backend, compare the residual voltage values ​​with the preset safety threshold, and when the residual voltage value exceeds the preset safety threshold, the auxiliary discharge branch is activated to suppress the residual overvoltage for a second time. The potential equalization control module is used to synchronously collect the potential distribution data of each branch of the grounding grid, and dynamically adjust the impedance parameters of each area's grounding branch according to the potential distribution data to equalize the current distribution of the entire current dissipation path. The device status monitoring module is used to continuously collect the operating parameters of the surge protection device, generate device aging status assessment results based on the operating parameters, and generate corresponding operation and maintenance early warning information based on the assessment results.

[0045] Furthermore, the lightning situation awareness module is specifically used for: Atmospheric electric field intensity data at multiple points in the field area are collected using a distributed electric field sensor array, and lightning electromagnetic pulse signals are collected using a lightning detection antenna. Trend fitting analysis was performed on atmospheric electric field intensity data to extract the electric field change rate and amplitude characteristics; spectrum analysis was performed on lightning electromagnetic pulse signals to extract the lightning occurrence distance and intensity characteristics. The electric field change rate and amplitude characteristics are fused with the lightning distance and intensity characteristics to generate a thunderstorm intrusion risk level. Based on the risk level of thunderstorm intrusion, a corresponding level of protection standby command is generated, driving the bleedering architecture to complete the pre-switching preparation for the corresponding level.

[0046] Furthermore, the tiered discharge control module is specifically used for: The instantaneous value of the lightning current in the main circuit is collected by a current transformer, and the instantaneous value of the bus overvoltage is collected by a voltage sensor. The instantaneous value of the lightning current is compared with the preset four-level current threshold, and the instantaneous value of the overvoltage is compared with the preset four-level voltage threshold to determine the lightning energy level. According to the lightning strike energy level, the corresponding branch combinations in the first-level coarse discharge branch, the second-level fine discharge branch, the third-level fine discharge branch, and the fourth-level micro discharge branch are connected in sequence. Through the current-limiting elements and nonlinear varistor elements in each level of the discharge branch, lightning energy of different frequencies and amplitudes is distributed proportionally.

[0047] Furthermore, the tiered discharge control module is specifically used for: When the lightning strike energy level reaches the first-level threshold, only the first-level coarse discharge branch is activated; When the lightning strike energy level reaches the second-level threshold, the first-level coarse discharge branch and the second-level fine discharge branch are simultaneously activated. When the lightning strike energy level reaches the third-level threshold, the first, second, and third-level discharge branches are simultaneously activated. When the lightning strike energy level reaches the fourth-level threshold, all fourth-level discharge branches are activated.

[0048] Furthermore, the residual pressure closed-loop suppression module is specifically used for: Voltage sampling points are set at the rear end of each bleed branch to synchronously collect the residual voltage values ​​at the output terminals of each stage. The residual voltage value of each level is compared with the corresponding residual voltage safety threshold in real time. When the residual voltage value of any stage exceeds the corresponding safety threshold, the auxiliary suppression branch connected in parallel with the current discharge branch of that stage is turned on. The residual voltage exceeding the threshold is clamped and absorbed by the active clamping element in the auxiliary suppression branch until the residual voltage falls back to the safe threshold range.

[0049] Furthermore, the potential equalization control module is specifically used for: Potential acquisition points are set at different branch nodes of the grounding grid to collect the ground potential value of each node in real time. Calculate the difference between the ground potential values ​​of each node to generate a global potential distribution gradient map; Identify local areas where the potential gradient exceeds a preset threshold and locate high-potential concentrated branches; Adjusting the impedance value of the adjustable impedance element in the high-potential concentrated branch increases the current dissipation of the branch and reduces the local potential concentration.

[0050] Furthermore, the device status monitoring module is specifically used for: Collect the leakage current value, surface temperature value, and cumulative number of operations of each surge protection device; The leakage current value is compared with the preset leakage current reference value, the surface temperature value is compared with the preset temperature reference value, and the device degradation score is generated by combining the cumulative value of the number of operations. When the device degradation score exceeds the preset warning threshold, a replacement warning message for the corresponding device is generated. Record the timing of each device's actions and energy tolerance data during each lightning strike to create a device operation history archive.

[0051] The fourth embodiment of the present invention provides a computer, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the overvoltage protection method for high-altitude mountain photovoltaic power stations as described above.

[0052] The fifth embodiment of the present invention provides a readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the overvoltage protection method for high-altitude mountain photovoltaic power stations as described above.

[0053] In summary, the overvoltage protection method and system for high-altitude mountain photovoltaic power stations provided by this invention addresses the complex lightning conditions of such power stations. Through a collaborative protection architecture of situational awareness, graded current discharge, residual voltage suppression, potential balancing, and device monitoring, it effectively improves the shortcomings of traditional lightning protection systems, such as chaotic hierarchical coordination and insufficient discharge capacity. The four-level layered current discharge architecture can adaptively match the working level according to the lightning strike intensity, covering the full range of intensity from weak induced lightning to strong direct lightning strikes, and realizing the orderly conduction of lightning energy step by step. Meanwhile, the forward-looking lightning situation awareness mechanism breaks through the limitations of traditional passive protection, enabling early prediction of lightning intrusion and pre-setting of protection measures, thus improving the system's response timeliness. The residual voltage closed-loop suppression mechanism can perform secondary clamping on residual overvoltages after each level of discharge, reducing the risk of power electronic equipment breakdown caused by excessive residual voltage. Mountain potential balancing control can dynamically adjust the impedance of grounding branches, improve the problem of local potential concentration caused by mountainous terrain, and reduce the potential difference across the entire area. Online device status monitoring can assess the aging degree of lightning protection devices in real time, identify potential failures in advance, and push early warnings, reducing the risk of devices operating with defects. Overall, it improves the comprehensiveness and reliability of lightning protection for high-altitude mountain photovoltaic power stations, ensuring the long-term stable operation of the stations.

[0054] Although the present invention has been described above with reference to embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, as long as there is no structural conflict, the features in the disclosed embodiments can be combined with each other in any manner. The lack of an exhaustive description of these combinations in this specification is merely for the sake of brevity and resource conservation. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An overvoltage protection method for high-altitude mountain photovoltaic power stations, characterized in that, The method includes: Real-time acquisition of atmospheric electric field data and lightning signals in the field area, identification of thunderstorm intrusion trends and generation of protection standby instructions, switching the system to the prevention and protection state and completing the preset discharge level; When a lightning strike occurs, the lightning current intensity and overvoltage amplitude parameters are collected, and the corresponding working position of the four-stage bleeder architecture is matched. The lightning energy is then conducted in layers through the bleeder branches that are connected in stages. The residual voltage values ​​at each level of protection are continuously collected and compared with the preset safety threshold. When the residual voltage value exceeds the preset safety threshold, the auxiliary discharge branch is activated to suppress the residual overvoltage for a second time. The potential distribution data of each branch of the grounding grid is collected synchronously, and the impedance parameters of each grounding branch in each area are dynamically adjusted according to the potential distribution data to balance the current distribution of the current dissipation path in the whole area. The system continuously collects the operating parameters of surge protection devices, generates device aging status assessment results based on the operating parameters, and generates corresponding operation and maintenance early warning information based on the assessment results.

2. The overvoltage protection method for high-altitude mountain photovoltaic power stations according to claim 1, characterized in that, The steps of real-time acquisition of atmospheric electric field data and lightning signals in the field area, identification of thunderstorm intrusion trends and generation of protection standby commands, switching the system to the prevention and protection state and completing the preset discharge level include: Atmospheric electric field intensity data at multiple points in the field area are collected using a distributed electric field sensor array, and lightning electromagnetic pulse signals are collected using a lightning detection antenna. Trend fitting analysis was performed on atmospheric electric field intensity data to extract the electric field change rate and amplitude characteristics; spectrum analysis was performed on lightning electromagnetic pulse signals to extract the lightning occurrence distance and intensity characteristics. The electric field change rate and amplitude characteristics are fused with the lightning distance and intensity characteristics to generate a thunderstorm intrusion risk level. Based on the risk level of thunderstorm intrusion, a corresponding level of protection standby command is generated, driving the bleedering architecture to complete the pre-switching preparation for the corresponding level.

3. The overvoltage protection method for high-altitude mountain photovoltaic power stations according to claim 1, characterized in that, When a lightning strike occurs, the steps of collecting lightning current intensity and overvoltage amplitude parameters, matching the corresponding operating level of the four-stage bleeder architecture, and conducting lightning energy in layers through the bleeder branches with progressively connected current include: The instantaneous value of the lightning current in the main circuit is collected by a current transformer, and the instantaneous value of the bus overvoltage is collected by a voltage sensor. The instantaneous value of the lightning current is compared with the preset four-level current threshold, and the instantaneous value of the overvoltage is compared with the preset four-level voltage threshold to determine the lightning energy level. According to the lightning strike energy level, the corresponding branch combinations in the first-level coarse discharge branch, the second-level fine discharge branch, the third-level fine discharge branch, and the fourth-level micro discharge branch are connected in sequence. Through the current-limiting elements and nonlinear varistor elements in each level of the discharge branch, lightning energy of different frequencies and amplitudes is distributed proportionally.

4. The overvoltage protection method for high-altitude mountain photovoltaic power stations according to claim 3, characterized in that, The step of sequentially activating the corresponding branch combinations in the first-stage coarse discharge branch, the second-stage fine discharge branch, the third-stage delicate discharge branch, and the fourth-stage micro discharge branch according to the lightning strike energy level includes: When the lightning strike energy level reaches the first-level threshold, only the first-level coarse discharge branch is activated; When the lightning strike energy level reaches the second-level threshold, the first-level coarse discharge branch and the second-level fine discharge branch are simultaneously activated. When the lightning strike energy level reaches the third-level threshold, the first, second, and third-level discharge branches are simultaneously activated. When the lightning strike energy level reaches the fourth-level threshold, all fourth-level discharge branches are activated.

5. The overvoltage protection method for high-altitude mountain photovoltaic power stations according to claim 1, characterized in that, The step of continuously collecting residual voltage values ​​at each level of protection backend, comparing the residual voltage values ​​with preset safety thresholds, and then, when the residual voltage value exceeds the preset safety threshold, activating the auxiliary bleed branch to perform secondary suppression of the residual overvoltage includes: Voltage sampling points are set at the rear end of each bleed branch to synchronously collect the residual voltage values ​​at the output terminals of each stage. The residual voltage value of each level is compared with the corresponding residual voltage safety threshold in real time. When the residual voltage value of any stage exceeds the corresponding safety threshold, the auxiliary suppression branch connected in parallel with the current discharge branch of that stage is turned on. The residual voltage exceeding the threshold is clamped and absorbed by the active clamping element in the auxiliary suppression branch until the residual voltage falls back to the safe threshold range.

6. The overvoltage protection method for high-altitude mountain photovoltaic power stations according to claim 1, characterized in that, The steps of synchronously acquiring potential distribution data of each branch of the grounding grid, dynamically adjusting the impedance parameters of each area's grounding branch based on the potential distribution data, and balancing the current distribution of the entire current dissipation path include: Potential acquisition points are set at different branch nodes of the grounding grid to collect the ground potential value of each node in real time. Calculate the difference between the ground potential values ​​of each node to generate a global potential distribution gradient map; Identify local areas where the potential gradient exceeds a preset threshold and locate high-potential concentrated branches; Adjusting the impedance value of the adjustable impedance element in the high-potential concentrated branch increases the current dissipation of the branch and reduces the local potential concentration.

7. The overvoltage protection method for high-altitude mountain photovoltaic power stations according to claim 1, characterized in that, The steps of continuously collecting operating parameters of surge protection devices, generating device aging status assessment results based on operating parameters, and generating corresponding maintenance early warning information based on assessment results include: Collect the leakage current value, surface temperature value, and cumulative number of operations of each surge protection device; The leakage current value is compared with the preset leakage current reference value, the surface temperature value is compared with the preset temperature reference value, and the device degradation score is generated by combining the cumulative value of the number of operations. When the device degradation score exceeds the preset warning threshold, a replacement warning message for the corresponding device is generated. Record the timing of each device's actions and energy tolerance data during each lightning strike to create a device operation history archive.

8. An overvoltage protection system for high-altitude mountain photovoltaic power stations, characterized in that, The system includes: The lightning situation awareness module is used to collect atmospheric electric field data and lightning signals in the field area in real time, identify the trend of thunderstorm intrusion and generate protection standby instructions, switch the system to the prevention and protection state and complete the preset of the discharge level. The graded discharge control module is used to collect lightning current intensity and overvoltage amplitude parameters when a lightning strike occurs, match the corresponding working level of the four-stage discharge architecture, and conduct lightning energy in layers through the discharge branches that are connected in stages. The residual voltage closed-loop suppression module is used to continuously collect the residual voltage values ​​at each level of protection backend, compare the residual voltage values ​​with the preset safety threshold, and when the residual voltage value exceeds the preset safety threshold, the auxiliary discharge branch is activated to suppress the residual overvoltage for a second time. The potential equalization control module is used to synchronously collect the potential distribution data of each branch of the grounding grid, and dynamically adjust the impedance parameters of each area's grounding branch according to the potential distribution data to equalize the current distribution of the entire current dissipation path. The device status monitoring module is used to continuously collect the operating parameters of the surge protection device, generate device aging status assessment results based on the operating parameters, and generate corresponding operation and maintenance early warning information based on the assessment results.

9. A computer comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the overvoltage protection method for high-altitude mountain photovoltaic power stations as described in any one of claims 1 to 7.

10. A readable storage medium having a computer program stored thereon, characterized in that, When executed by the processor, the program implements the overvoltage protection method for high-altitude mountain photovoltaic power stations as described in any one of claims 1 to 7.

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