Method and system for configuring lightning arrester based on simulation calculation of lightning intrusion waves

Abstract

The invention discloses a method and a system for configuring lightning arresters based on simulation calculation of lightning intrusion waves. The method comprises the following steps: determining initial arrangement and initial key parameters of lightning arresters at an alternating current side and a direct current side; adjusting the initial key parameter and the initial arrangement based on a temporary overvoltage and a slow wavefront overvoltage, and determining a first optimization key parameter and a first optimization arrangement; adjusting the first optimization key parameter and the first optimization arrangement based on the lightning overvoltage and the steep wavefront overvoltage, and determining a second optimization key parameter and a second optimization arrangement; based on the second optimization arrangement and the second optimization key parameter, determining the matching current and the protection level of the lightning arrester; and determining a dual selection principle of the lightning arrester based on the maximum overvoltage of the insulation position determined by the second optimization arrangement and the second optimization key parameter, and configuring the lightning arrester.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic transient simulation technology in high voltage technology, and more specifically, to a method and system for configuring surge arresters based on simulation calculations of lightning intrusion waves. Background Technology

[0002] Promoting the green energy transition and building a new power system with new energy sources as the mainstay is the only way for my country to achieve its dual-carbon goals. However, my country's new energy resources such as wind and solar power exhibit a significant east-west inverse distribution to load centers. The practical constraints of "source-load separation" and the randomness, volatility, and intermittency of wind and solar energy urgently require my country to vigorously develop large-capacity, long-distance, and flexible power transmission technologies.

[0003] Ultra-high voltage flexible direct current (VSC-HVDC) transmission technology, employing voltage source converters and fully controlled devices such as IGBTs as the main circuit power devices, does not rely on the self-commutation capability of the external AC grid and has broad application prospects in the field of large-capacity, long-distance renewable energy consumption. However, due to the limitations of IGBT device performance, the application of VSC technology in ultra-high voltage direct current transmission projects still suffers from prominent shortcomings such as high cost, high losses, and insufficient valve current-carrying capacity. The reliability of VSC multi-valve cascade technology in ±800kV ultra-high voltage projects still needs to be verified by the operation of the Wudongde project, and it cannot yet provide a safe and economical solution for high-proportion renewable energy DC transmission. The hybrid cascading technology of VSC converters and LCC (line commutated converter) allows UHVDC flexible DC systems to not only possess the strong adaptability and flexible control of VSC converters in weak network conditions, but also the large capacity, low loss, low cost, and strong short-term overcurrent withstand capability of LCC converters. Furthermore, it offers advantages such as autonomous DC fault clearing and improved short-circuit ratio in the receiving-end system. Therefore, by flexibly combining traditional DC transmission converters (LCC) with flexible DC transmission converters (VSC), a new hybrid DC transmission technology is formed that simultaneously leverages the advantages of low cost, low loss, and large capacity of LCC-HVDC, as well as the absence of commutation failure and flexible control of VSC-HVDC.

[0004] Ultra-high voltage direct current (UHVDC) converter stations typically employ a combination of lightning rods and conductors for lightning protection. However, based on past operational experience, the chance of lightning striking the transmission line is far greater than the chance of lightning bypassing the lightning rod or conductor and directly striking the converter station equipment. Lightning strikes to the ground wire or tower can cause insulation backflashover, allowing lightning current to enter the conductors. Alternatively, lightning can directly strike the conductors, creating lightning overvoltage traveling waves that intrude into the converter station along the line. These overvoltages can exceed the insulation levels of the equipment, posing a significant threat to the safe operation of the converter station. Therefore, lightning intrusion wave overvoltage protection is a key research focus.

[0005] When a converter station adopts a hybrid cascaded LCC-VSC arrangement, during valve group operation, when lightning traveling waves intrude from the pole line, they may enter the hybrid cascaded valve group area through the DC filter. The insulation level of this area is much lower than that of the DC pole line. It is necessary to adjust the arrangement of surge arresters in the DC field of the converter station through calculation to ensure the safe and reliable operation of the DC field. Summary of the Invention

[0006] The present invention provides a method and system for configuring surge arresters based on simulation calculations of lightning intrusion waves, in order to solve the problem of how to determine the corresponding suppression measures and insulation coordination design by calculating the overvoltage level.

[0007] To address the aforementioned problems, this invention provides a method for configuring surge arresters based on simulation calculations of lightning intrusion waves, the method comprising:

[0008] Determine the initial layout and key parameters of the surge arresters on the AC and DC sides;

[0009] Based on temporary overvoltage and slow-wave front overvoltage, the initial key parameters and the initial arrangement are adjusted to determine the first optimized key parameters and the first optimized arrangement;

[0010] Based on lightning overvoltage and steep wavefront overvoltage, the first optimized key parameters and the first optimized arrangement are adjusted to determine the second optimized key parameters and the second optimized arrangement.

[0011] Based on the second optimized arrangement and the second optimized key parameters, the coordination current and protection level of the surge arrester are determined;

[0012] Based on the dual selection principle of determining the surge arrester according to the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters, the surge arrester is configured.

[0013] Preferably, the determination of the initial arrangement and initial key parameters of the AC-side and DC-side surge arresters, wherein,

[0014] The initial key parameters for the communication side include:

[0015] Determine the rated voltage Ur to be ≥ 1.05~1.1×U 工频 ,max (safety margin), U 工频 = K × Un, where Un is the system's rated line voltage, K is the overvoltage multiple (1.3-1.5 for 220kV systems, 1.2-1.4 for 500kV systems), U 工频 ,max (safety margin) is the maximum value of the power frequency voltage; control the leakage current under rated voltage to ≤100μA, and control the distance between the surge arrester on the AC side and the protected equipment to ≤900m;

[0016] The initial key parameters on the DC side include:

[0017] The continuous operating voltage CCOV ≥ Uc,max and the temporary overvoltage withstand voltage PCOV ≥ Uch,max are satisfied. ch ,max is the maximum value of temporary overvoltage, and Uc,max is the maximum value of continuous operating voltage; combined with a charge rate of 65%-75%, the DC reference voltage Uref=CCOV / η is calculated, where η is the charge rate of the surge arrester; the distance between the surge arrester on the DC side and the protected equipment is controlled to be ≤900m.

[0018] Preferably, the step of adjusting the initial key parameters and initial arrangement based on temporary overvoltage and soft-front overvoltage to determine the first optimized key parameters and first optimized arrangement includes:

[0019] Typical fault conditions are identified, including the duration of the temporary overvoltage of 0.1s-10s and the wavefront time of the slow wavefront overvoltage of 50μs-1000μs.

[0020] Based on the typical fault conditions, the structural parameters of the surge arrester are determined, including: the number of series resistors in the surge arrester, the number of internal valve columns in parallel, and the number of external surge arresters in parallel.

[0021] When the initial key parameters or initial arrangement do not meet the structural parameters of the surge arrester, the initial key parameters or initial arrangement are adjusted to determine the first optimized key parameters and the first optimized arrangement.

[0022] Preferably, the step of adjusting the first optimized key parameters and the first optimized arrangement based on lightning overvoltage and steep wavefront overvoltage to determine the second optimized key parameters and the second optimized arrangement includes:

[0023] The wavefront time of lightning overvoltage was determined to be 1μs-10μs, the steep wavefront overvoltage, and the target protection area.

[0024] Based on the target protection area and the determined wavefront time of the lightning overvoltage, simulation calculations are performed to determine the structural parameters of the surge arrester, including: the maximum residual lightning voltage and discharge current of the surge arrester.

[0025] When the first optimized key parameter or the first optimized arrangement does not meet the determined structural parameters of the surge arrester, the initial key parameter or the initial arrangement is adjusted to determine the second optimized key parameter and the second optimized arrangement.

[0026] Preferably, determining the surge arrester's coordination current and protection level based on the determined second optimized arrangement and second optimized key parameters of the surge arrester includes:

[0027] Based on temporary overvoltage, slow-wave front overvoltage, lightning overvoltage, and steep-wave front overvoltage, the coordination current, impulse protection level, and energy withstand requirements of the surge arrester are determined, wherein: the coordination current is not less than the maximum discharge current, the impulse protection level is not higher than the equipment insulation withstand reference parameter and a preset margin, and the energy withstand requirement is higher than the energy withstand baseline value.

[0028] Preferably, the dual selection principle for determining the surge arrester based on the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters includes:

[0029] Calculate the effective energy absorbed by the surge arrester based on the minimum VI protection characteristics;

[0030] Calculate the range of residual voltage difference values ​​for surge arresters based on the maximum residual voltage deviation characteristics;

[0031] The maximum protection level of the surge arrester is calculated based on the maximum VI protection characteristics.

[0032] According to another aspect of the present invention, the present invention provides a system for configuring surge arresters based on simulation calculations of lightning intrusion waves, the system comprising:

[0033] The initial unit is used to determine the initial arrangement and key parameters of the surge arresters on the AC and DC sides.

[0034] The first adjustment unit is used to adjust the initial key parameters and the initial arrangement based on the temporary overvoltage and the slow wave front overvoltage, and to determine the first optimized key parameters and the first optimized arrangement.

[0035] The second adjustment unit is used to adjust the first optimization key parameters and the first optimization arrangement based on lightning overvoltage and steep wavefront overvoltage, and to determine the second optimization key parameters and the second optimization arrangement.

[0036] The first determining unit is used to determine the coordination current and protection level of the surge arrester based on the second optimized arrangement and the second optimized key parameters;

[0037] The second determining unit is used to configure the surge arrester based on the dual selection principle of determining the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters.

[0038] Preferably, the initial unit is used to determine the initial arrangement and initial key parameters of the AC-side and DC-side surge arresters, wherein,

[0039] The initial key parameters for the communication side include:

[0040] Determine the rated voltage Ur to be ≥ 1.05~1.1×U 工频 ,max (safety margin), U 工频 = K × Un, where Un is the system's rated line voltage, K is the overvoltage multiple (1.3-1.5 for 220kV systems, 1.2-1.4 for 500kV systems), U 工频 ,max (safety margin) is the maximum value of the power frequency voltage; control the leakage current under rated voltage to ≤100μA, and control the distance between the surge arrester on the AC side and the protected equipment to ≤900m;

[0041] The initial key parameters on the DC side include:

[0042] The continuous operating voltage CCOV ≥ Uc,max and the temporary overvoltage withstand voltage PCOV ≥ Uch,max are satisfied. ch ,max is the maximum value of temporary overvoltage, and Uc,max is the maximum value of continuous operating voltage; combined with a charge rate of 65%-75%, the DC reference voltage Uref=CCOV / η is calculated, where η is the charge rate of the surge arrester; the distance between the surge arrester on the DC side and the protected equipment is controlled to be ≤900m.

[0043] Preferably, the first adjustment unit is used to adjust the initial key parameters and initial arrangement based on temporary overvoltage and soft-front overvoltage, and to determine the first optimized key parameters and first optimized arrangement, including:

[0044] Typical fault conditions are identified, including the duration of the temporary overvoltage of 0.1s-10s and the wavefront time of the slow wavefront overvoltage of 50μs-1000μs.

[0045] Based on the typical fault conditions, the structural parameters of the surge arrester are determined, including: the number of series resistors in the surge arrester, the number of internal valve columns in parallel, and the number of external surge arresters in parallel.

[0046] When the initial key parameters or initial arrangement do not meet the structural parameters of the surge arrester, the initial key parameters or initial arrangement are adjusted to determine the first optimized key parameters and the first optimized arrangement.

[0047] Preferably, the second adjustment unit is used to adjust the first optimization key parameters and the first optimization arrangement based on the lightning overvoltage and the steep wavefront overvoltage, and to determine the second optimization key parameters and the second optimization arrangement, including:

[0048] The wavefront time of lightning overvoltage was determined to be 1μs-10μs, the steep wavefront overvoltage, and the target protection area.

[0049] Based on the target protection area and the determined wavefront time of the lightning overvoltage, simulation calculations are performed to determine the structural parameters of the surge arrester, including: the maximum residual lightning voltage and discharge current of the surge arrester.

[0050] When the first optimized key parameter or the first optimized arrangement does not meet the determined structural parameters of the surge arrester, the initial key parameter or the initial arrangement is adjusted to determine the second optimized key parameter and the second optimized arrangement.

[0051] Preferably, the first determining unit is used to determine the coordination current and protection level of the surge arrester based on the determined second optimized arrangement and second optimized key parameters of the surge arrester, including:

[0052] Based on temporary overvoltage, slow-wave front overvoltage, lightning overvoltage, and steep-wave front overvoltage, the coordination current, impulse protection level, and energy withstand requirements of the surge arrester are determined, wherein: the coordination current is not less than the maximum discharge current, the impulse protection level is not higher than the equipment insulation withstand reference parameter and a preset margin, and the energy withstand requirement is higher than the energy withstand baseline value.

[0053] Preferably, the second determining unit is used to determine the dual selection principle of the surge arrester based on the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters, including:

[0054] Calculate the effective energy absorbed by the surge arrester based on the minimum VI protection characteristics;

[0055] Calculate the range of residual voltage difference values ​​for surge arresters based on the maximum residual voltage deviation characteristics;

[0056] The maximum protection level of the surge arrester is calculated based on the maximum VI protection characteristics.

[0057] According to another aspect of the present invention, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of a method for configuring a surge arrester based on a simulation calculation of a lightning intrusion wave.

[0058] According to another aspect of the present invention, the present invention provides an electronic device, comprising:

[0059] The aforementioned computer-readable storage medium; and

[0060] One or more processors for executing a program in the computer-readable storage medium.

[0061] This invention provides a method and system for configuring surge arresters based on simulation calculations of lightning surge waves. The method includes: determining the initial arrangement and initial key parameters of the AC and DC side surge arresters; adjusting the initial key parameters and initial arrangement based on temporary overvoltages and slow-wave front overvoltages to determine first optimized key parameters and a first optimized arrangement; adjusting the first optimized key parameters and the first optimized arrangement based on lightning overvoltages and steep-wave front overvoltages to determine second optimized key parameters and a second optimized arrangement; determining the surge arrester's coordination current and protection level based on the second optimized arrangement and the second optimized key parameters; and determining the surge arrester's dual selection principle based on the maximum overvoltage at the insulation location determined by the second optimized arrangement and the second optimized key parameters, and configuring the surge arrester accordingly. This invention calculates the overvoltage level to determine corresponding suppression measures and insulation coordination design schemes. The technical solution of this invention enables the acquisition of overvoltage levels of lightning intrusion waves under various operating conditions inside the DC field equipment of an UHVDC converter station, considering different operating modes, layout schemes, and lightning intrusion methods. Based on the calculation results, corresponding suppression measures and insulation coordination schemes are proposed. This simulation calculation method can guide engineering design and provide data support for the design of UHVDC converter stations. Attached Figure Description

[0062] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures:

[0063] Figure 1 This is a flowchart of a method for configuring a surge arrester based on simulation calculations of lightning intrusion waves according to a preferred embodiment of the present invention.

[0064] Figure 2 The flowchart below shows the insulation coordination method for simulation calculation of lightning intrusion wave overvoltage in an ultra-high voltage direct current converter station according to a preferred embodiment of the present invention.

[0065] Figure 3 This is a schematic diagram of a triangular lightning current waveform according to a preferred embodiment of the present invention;

[0066] Figure 4 This is a schematic diagram illustrating the relationship between the lightning current impedance and the lightning current amplitude according to a preferred embodiment of the present invention.

[0067] Figure 5 This is a schematic diagram of the grounding electrode impedance at the base of a tower according to a preferred embodiment of the present invention;

[0068] Figure 6 This is a schematic diagram of a smoothing reactor according to a preferred embodiment of the present invention;

[0069] Figure 7 This is a schematic diagram of a converter valve assembly according to a preferred embodiment of the present invention;

[0070] Figure 8 This is a schematic diagram of the equivalent circuit when the valve is closed according to a preferred embodiment of the present invention;

[0071] Figure 9 This is a schematic diagram of the equivalent circuit when the valve is turned on according to a preferred embodiment of the present invention;

[0072] Figure 10 The lightning arrester according to a preferred embodiment of the present invention is represented by a model of two nonlinear resistors connected in parallel.

[0073] Figure 11 This is a schematic diagram of a typical topology of a hybrid cascaded DC system according to a preferred embodiment of the present invention;

[0074] Figure 12 The above is a typical waveform diagram of lightning intrusion wave overvoltage in a wall bushing of an ultra-high voltage direct current converter station according to a preferred embodiment of the present invention.

[0075] Figure 13 The diagram shows the overvoltage at both ends of the smoothing reactor and the discharge current of the DR1 surge arrester, obtained by calculating the DC filter of the UHV converter station simultaneously shut down, the conductor of tower No. 3 with a negative polarity of 20kA' lightning current striking the P1 pole, and the calculation of the preferred embodiment of the present invention.

[0076] Figure 14 This is a system structure diagram of a surge arrester configured based on simulation calculation of lightning intrusion wave according to a preferred embodiment of the present invention. Detailed Implementation

[0077] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0078] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0079] Figure 1 This is a flowchart of a method for configuring a surge arrester based on simulation calculations of lightning intrusion waves according to a preferred embodiment of the present invention.

[0080] This invention provides a simulation calculation method for lightning intrusion wave overvoltage in an ultra-high voltage direct current converter station based on the ATP-EMTP electromagnetic transient simulation software.

[0081] This invention can obtain the overvoltage level of lightning intrusion waves under various operating conditions inside the DC field equipment of an UHVDC converter station, based on different operating modes, layout schemes, and lightning intrusion methods. According to the calculation results, corresponding suppression measures and insulation coordination schemes are proposed. This simulation calculation method can guide engineering design and provide data support for the design of UHVDC converter stations.

[0082] DC converter stations are core nodes in high-voltage direct current (HVDC) transmission systems, responsible for the conversion and transmission of AC and DC power. The insulation safety of their equipment directly determines the system's operational stability. Lightning surge waves, one of the main overvoltage threats faced by converter stations, are characterized by high amplitude (up to several thousand kilovolts), steep gradient (wavefront time often less than 10 μs), and strong destructive power. They can break down the insulation of critical equipment such as converter valves, main transformers, and DC reactors, causing major power outages. Therefore, accurately calculating lightning surge waves and scientifically determining the placement and parameters of surge arresters are core tasks in the converter station design phase.

[0083] The simulation tool used is ATP (Alternative Transient Program), one of the most widely used digital simulation software programs internationally for calculating electromagnetic transient phenomena and applying motor principles. It is a continuation and development of the BPAEMTP (Electromagnetic Transient Program) program, developed by Dommel-Bergler during his work at the Bernieville Power Authority (BPA) in the late 1950s. The frequency range needs to be matched according to the overvoltage type: lightning overvoltage frequencies can reach up to 1MHz, requiring consideration of distributed line parameters and high-frequency impedance of equipment (such as transformer input capacitance); transient overvoltage frequencies are lower (50Hz-1kHz), allowing for a simplified model while retaining the power frequency characteristics of the equipment. Modeling must comply with IEC 60071-4 standards; for example, the JMarti model should be used for the line model (considering frequency dependence), and a nonlinear resistance model should be used for the surge arrester model (simulating VI characteristics) to ensure that the simulation results are consistent with actual operating conditions.

[0084] like Figure 1 As shown, this invention provides a method for configuring surge arresters based on simulation calculations of lightning intrusion waves. The method includes:

[0085] Step 101: Determine the initial layout and key parameters of the surge arresters on the AC and DC sides;

[0086] Preferably, the initial arrangement and initial key parameters of the surge arresters on the AC and DC sides are determined, wherein,

[0087] The initial key parameters for the communication side include:

[0088] Determine the rated voltage Ur to be ≥ 1.05~1.1×U 工频 ,max (safety margin), U 工频 = K × Un, where Un is the system's rated line voltage, K is the overvoltage multiple (1.3-1.5 for 220kV systems, 1.2-1.4 for 500kV systems), U 工频 ,max (safety margin) is the maximum value of the power frequency voltage; control the leakage current under rated voltage to ≤100μA, and control the distance between the surge arrester on the AC side and the protected equipment to ≤900m;

[0089] The initial key parameters on the DC side include:

[0090] The continuous operating voltage CCOV ≥ Uc,max and the temporary overvoltage withstand voltage PCOV ≥ Uch,max are satisfied. ch ,max is the maximum value of temporary overvoltage, Uc,max is the maximum value of continuous operating voltage. Combined with a charge rate of 65%-75%, the DC reference voltage Uref = CCOV / η, where η is the charge rate of the surge arrester; the distance between the surge arrester on the DC side and the protected equipment should be ≤900m. For example... Figure 2 As shown.

[0091] DC converter stations are core nodes in high-voltage direct current (HVDC) transmission systems, responsible for the conversion and transmission of AC and DC power. The insulation safety of their equipment directly determines the system's operational stability. Lightning surge waves, one of the main overvoltage threats faced by converter stations, are characterized by high amplitude (up to several thousand kilovolts), steep gradient (wavefront time often less than 10 μs), and strong destructive power. They can break down the insulation of critical equipment such as converter valves, main transformers, and DC reactors, causing major power outages. Therefore, accurately calculating lightning surge waves and scientifically determining the placement and parameters of surge arresters are core tasks in the converter station design phase.

[0092] The simulation tool used is ATP (Alternative Transient Program). This invention requires matching the frequency range according to the overvoltage type: lightning overvoltage frequencies can reach up to 1MHz, necessitating consideration of distributed line parameters and high-frequency impedance of equipment (such as the transformer's input capacitance); transient overvoltage frequencies are lower (50Hz-1kHz), allowing for a simplified model while retaining the equipment's power frequency characteristics. Modeling must comply with the IEC 60071-4 standard. For example, the line model may use the JMarti model (considering frequency dependence), and the surge arrester model may use a nonlinear resistance model (simulating VI characteristics) to ensure that the simulation results are consistent with actual operating conditions.

[0093] The parameter settings for the calculation model of lightning intrusion wave in this invention are as follows:

[0094] (1) Lightning current waveform

[0095] Lightning waveforms widely employ a 2.6 / 50μs triangular current waveform. For example... Figure 3 As shown, Figure 3 middle, I f It is the current amplitude, t f It is the wave head time, t h It is the wave tail time.

[0096] (2) Lightning channel impedance

[0097] The lightning leader channel can be approximated as a conductive channel with uniformly distributed parameters such as inductance and capacitance; that is, the main discharge can be considered to occur along an equal wave impedance of Z. M The lightning channel impedance Z propagates through an infinitely long conductor. M =300~3000Ω.

[0098] The lightning current impedance is related to the main discharge channel lightning current, and decreases as the lightning current amplitude increases. (See...) Figure 4 Among them, the lightning withstand level of ±800kV lines is about 15 to 25kA, and the corresponding lightning surge impedance is relatively large, about 225 to 500Ω. The lightning surge impedance can be used for lightning strike calculation; the lightning surge impedance can be approximated as 300Ω for backflash calculation.

[0099] (3) Grounding resistance of the tower

[0100] The physical phenomena involved when lightning-struck tower current flows through the grounding electrode are extremely complex. Therefore, accurately representing both conduction and ionization simultaneously is very difficult. One approach is to... Figure 5 The model shown is a grounding electrode model for the tower, but its effectiveness is difficult to assess.

[0101] Simplified model: According to IEC 60071-4, the impedance at the tower root can also be represented by resistance alone. An impedance model can also be used, with typical values ​​for L and C being a few μH and a few pF, respectively.

[0102] Ionization model: Due to the high amplitude grounding current flowing through the grounding resistance during a lightning strike, the ionization effect can be considered and the grounding resistance can be expressed as a nonlinear resistance, the value of which can be calculated according to the following formula (see IEC60071-2-2002).

[0103] According to IEC60071-4, this model is only valid if the resistance at the base of the tower is within a radius of 30m.

[0104] If I < I g Then R = R0

[0105] If I > I g but

[0106] Here:

[0107]

[0108] In the formula:

[0109] R0 is the resistance (Ω) when the current is small and the frequency is low;

[0110] I is the lightning current (A) flowing through the root impedance;

[0111] I g It is the current limiting value (A);

[0112] ρ is the soil resistivity (Ω×m)

[0113] E0 is the soil ionization gradient (recommended value: E0≈400kV×m) -1 )

[0114] (4) Smoothing reactor model

[0115] Each pole of the converter station has two 75mH smoothing reactors connected in series with the neutral bus, each with an inductance of 150mH. An example of a high-frequency model for a single smoothing reactor considering inductance, post insulator-to-ground capacitance, inter-turn capacitance, and stray capacitance can be found in [link to high-frequency model]. Figure 6 The ground capacitance value related to the number of post insulators needs to be determined based on the CAD drawing of the smoothing reactor.

[0116] (5) Smoothing reactor model

[0117] A single converter valve consists of two components connected in series. Each component is the smallest complete structural unit of the converter valve, including multiple high-voltage thyristors connected in series, and auxiliary circuitry for the high-voltage thyristors. Figure 7An example of a single-valve model is given. Each thyristor requires a buffer circuit in parallel to dampen commutation overshoot and to even out the series voltage distribution. To protect the thyristors from the high inrush current generated by the discharge of the buffer circuit and external distributed capacitor during conduction, a saturated reactor is connected in series with the thyristor to improve the thyristor's ability to suppress di / dt. Another voltage-equalizing capacitor is connected in parallel to the assembly to even out the voltage between the assemblies. The value of the saturated reactor is a nonlinear characteristic related to the frequency and amplitude of the lightning current and can be provided by the valve manufacturer.

[0118] Based on the on / off state of the converter valve, the valve circuit is simplified.

[0119] When lightning enters the valve hall, a simplified high-frequency model of the converter valve can be used to calculate the lightning overvoltage to ground of the uppermost valve or the lightning overvoltage entering the side bushing end of the converter transformer valve through the conducting valve.

[0120] Figure 8 In option 9, L` = 30mH, C1` = 20000pF, C2` = 1000pF, and R1` = 5400Ω.

[0121] To calculate the lightning overvoltage distribution of the valve body, a detailed simulation of the parasitic capacitances of the valve modules, shielding plates, and each valve tower is required. This includes: the capacitance between two valve modules on the same floor; the capacitance between valve modules on different floors; the capacitance of each valve module to ground; and the capacitance of the first-floor valve module to the shielding plate. The capacitance of the valve module to ground consists of three parts: capacitance to the valve hall floor, capacitance to the walls, and capacitance to the ceiling.

[0122] (6) Metal oxide surge arresters

[0123] The surge arrester can be characterized by an 8 / 20 μs volt-ampere characteristic, provided by the manufacturer, and includes stray capacitance (required only for GIS) and grounding inductance (linear inductance approximately 1 μH / m). An additional inductance can be added to represent the time delay. A more accurate model can be found in the IEEE documentation, which represents the surge arrester as two nonlinear resistors in parallel. Parameter selection for the surge arrester model is detailed in [link to relevant documentation]. Figure 10 .

[0124] α = 11

[0125] L1 = 1(μH)

[0126] R2 = 31Ω

[0127] L2 = 7.4 (μH)

[0128] C = 170pF

[0129] MOA surge arrester lightning discharge volt-ampere characteristic curve

[0130] (7) Disconnecting switches and post insulators

[0131] The capacitance between poles and neutral bus disconnect switches is represented by the capacitance between the contacts and between the contacts and ground. Generally, the capacitance to ground of the posts at both ends of a DC high-voltage disconnect switch is 150pF, the capacitance between the contacts and the break points is 100pF, and the capacitance to ground of the post insulator is generally 150pF.

[0132] This invention first preliminarily determines the arrangement and key parameters of AC and DC surge arresters.

[0133] Surge arresters are the core equipment for suppressing lightning surge waves. Their initial layout and parameter selection need to be combined with the converter station topology, equipment distribution and AC / DC system characteristics to lay the foundation for subsequent calculations.

[0134] The core parameter of an AC-side surge arrester is its rated voltage, which needs to be determined based on the volt-second characteristics of AC power frequency overvoltages. AC-side power frequency overvoltages originate from conditions such as no-load line closing and fault clearing; their waveform is close to a sine wave, and their duration ranges from 0.1 seconds to several seconds. Calculations can be performed using ATP-EMTP software to construct a system model, simulating the overvoltage amplitude under different operating conditions, or by employing simplified engineering formulas (such as U...). 工频 = K × Un, where Un is the system's rated line voltage, and K is the overvoltage multiple (1.3-1.5 for 220kV systems and 1.2-1.4 for 500kV systems) for quick estimation. When selecting a system, Ur ≥ 1.05~1.1 × U 工频 ,max (reserve safety margin), and at the same time control the leakage current under rated voltage to ≤100μA to avoid aging of the surge arrester.

[0135] The parameters of the DC-side surge arrester need to be considered in conjunction with the continuous operating voltage (Uc) and temporary overvoltage (U) at the installation location. ch Confirmed. c It is the DC voltage that exists continuously during normal operation, such as the DC bus U of a ±800kV system. c Approximately 800kV, with fluctuations not exceeding ±5%; U ch This refers to a short-term overvoltage that occurs during a fault (such as a voltage surge due to commutation failure), lasting 0.1s-10s. Based on this, the continuous operating voltage (CCOV ≥ Uc,max) and temporary overvoltage withstand voltage (PCOV ≥ Uch,max) are selected, and the DC reference voltage Uref = CCOV / η is calculated in conjunction with the charge rate (65%-75%). The arrangement must cover lightning intrusion paths, such as AC busbars and DC line outlets, ensuring that the distance between the surge arrester and the protected equipment does not exceed the protection distance (based on a surge velocity of 3×10⁻⁶). 8 m / s, the difference between the surge arrester's operating time and the equipment's breakdown time is calculated, typically ≤900m).

[0136] Step 102: Based on temporary overvoltage and slow-wave front overvoltage, adjust the initial key parameters and initial layout to determine the first optimized key parameters and the first optimized layout;

[0137] Preferably, based on temporary overvoltage and soft-front overvoltage, the initial key parameters and initial layout are adjusted to determine the first optimized key parameters and the first optimized layout, including:

[0138] Typical fault conditions were identified, including temporary overvoltage duration of 0.1s-10s and pre-wave overvoltage wavefront time of 50μs-1000μs.

[0139] Based on typical fault conditions, determine the structural parameters of the surge arrester, including: the number of series resistors in the surge arrester, the number of internal valve columns connected in parallel, and the number of external surge arresters connected in parallel.

[0140] When the initial key parameters or initial arrangement do not meet the structural parameters of the surge arrester, the initial key parameters or initial arrangement are adjusted to determine the first optimized key parameters and the first optimized arrangement.

[0141] This invention studies temporary and mitigating wavefront overvoltages and optimizes surge arrester structural parameters:

[0142] Temporary overvoltages (lasting 0.1s-10s) and slow-wave front overvoltages (50μs-1000μs before the wavefront) have low amplitudes but high energy, easily leading to overheating of the surge arrester varistor. It is necessary to first identify typical fault conditions, such as single-phase grounding on the AC side and DC line fault clearing, and then determine the maximum slow-wave front residual voltage, discharge current, and absorbed energy of the surge arrester through simulation.

[0143] The structural parameters of the surge arrester are determined based on the probability of operating conditions (e.g., the annual occurrence rate of severe operating conditions ≤ 0.01): the number of series resistors must meet the requirement that the withstand voltage of a single column is ≥ PCOV, which can be calculated by superimposing the rated voltages of the valves; the number of internal parallel columns must ensure uniform distribution of discharge current to avoid overload of a single column; the number of external parallel arresters is determined based on the total energy demand, such as 5 arresters needing to be connected in parallel when the energy withstand capacity of a single arrester is 10kJ and the total energy demand is 50kJ. If the parameters do not meet the requirements, it is necessary to return to step 1 to adjust the arrester arrangement or rated voltage, such as by adding intermediate arresters or increasing the CCOV level.

[0144] Step 103: Based on lightning overvoltage and steep wavefront overvoltage, adjust the first optimization key parameters and the first optimization arrangement, and determine the second optimization key parameters and the second optimization arrangement;

[0145] Preferably, based on lightning overvoltage and steep wavefront overvoltage, the first optimized key parameters and the first optimized arrangement are adjusted to determine the second optimized key parameters and the second optimized arrangement, including:

[0146] The wavefront time of lightning overvoltage was determined to be 1μs-10μs, the steep wavefront overvoltage, and the target protection area.

[0147] Based on the target protection area and the wavefront time of the lightning overvoltage, simulation calculations are performed to determine the structural parameters of the surge arrester, including the maximum lightning residual voltage and discharge current of the surge arrester.

[0148] When the first optimized key parameters or the first optimized arrangement do not meet the determined structural parameters of the surge arrester, the initial key parameters or the initial arrangement are adjusted to determine the second optimized key parameters and the second optimized arrangement.

[0149] This invention studies lightning and steep wavefront overvoltage, and verifies and improves the arrangement.

[0150] Lightning overvoltage (1-10μs before the wavefront) and steep wavefront overvoltage are the core of the intrusion wave calculation, and it is necessary to verify whether the parameters determined in the first two steps are effective. By simulating direct lightning strikes or induced intrusion scenarios, such as a DC line being subjected to a 200kA lightning current impact, the maximum lightning residual voltage and discharge current of the surge arrester are calculated to determine whether they meet the equipment insulation withstand requirements (the equipment insulation level must be 10%-15% higher than the surge arrester residual voltage).

[0151] Different methods should be used to study lightning and steep-front overvoltages in different areas of a high-voltage direct current converter station. These areas include:

[0152] AC switchyard area: from the AC line inlet to the converter transformer grid-side line end;

[0153] DC switch field area: from the DC line inlet to the line-side end of the smoothing reactor;

[0154] Converter bridge area (valve hall): from the valve side of the converter transformer to the valve side of the smoothing reactor.

[0155] The converter bridge area is separated from the other two areas by series reactors on both sides. One side has smoothing reactor reactance, and the other side has converter transformer leakage reactance. Lightning intrusion waves from the AC side of the converter transformer and the DC side outside the smoothing reactor, under the combined attenuation of the series reactors and ground capacitance on both sides (and possibly transmitted through capacitance), reach the converter bridge area with a waveform similar to a soft-front overvoltage. Therefore, it can be used for insulation coordination as a soft-front overvoltage.

[0156] The lightning overvoltage in the converter station's DC switchyard mainly originates from the lightning intrusion wave overvoltage in the incoming section of the 2km DC pole line and grounding line connected to the DC switchyard, as well as the direct lightning strike overvoltage in the converter station's DC field. The DC switchyard pole lines and grounding lines are equipped with equipment such as smoothing reactors and DC filters to dampen lightning waves. Multiple sets of surge arresters are present at the DC pole line entrance, metallic return line, grounding line entrance, and neutral busbar, so the lightning overvoltage is generally not particularly severe.

[0157] Simultaneously consider the distance effect of surge arrester protection: when the distance between the equipment and the surge arrester exceeds the protection distance, the wave propagation time is prolonged, which may cause the equipment to break down first. In this case, an additional surge arrester is required. If the simulation shows that the residual voltage exceeds the standard, the surge arrester parameters need to be adjusted, such as reducing the charge rate to reduce the residual voltage, or increasing the number of parallel columns to improve the current withstand capability.

[0158] Step 104: Based on the second optimized layout and the second optimized key parameters, determine the matching current and protection level of the surge arrester;

[0159] Preferably, based on the determined second optimized arrangement and second optimized key parameters of the surge arrester, the coordination current and protection level of the surge arrester are determined, including:

[0160] Based on temporary overvoltage, slow-wave front overvoltage, lightning overvoltage, and steep-wave front overvoltage, determine the surge arrester's coordination current, impulse protection level, and energy withstand requirements. Among these requirements, the coordination current shall not be less than the maximum discharge current, the impulse protection level shall not be higher than the equipment insulation withstand reference parameter with a preset margin, and the energy withstand requirement shall be higher than the energy withstand baseline value.

[0161] This invention determines the surge arrester's matching current and protection level, and establishes standards.

[0162] Based on the overvoltage calculation results from the first two steps, determine the surge arrester's coordination current, impulse protection level, and energy requirements. The coordination current must be greater than the maximum discharge current to ensure the surge arrester is not damaged under extreme conditions. The impulse protection level is determined by combining the lightning residual voltage and the steep wave front residual voltage, and must be less than the equipment's basic insulation level (BIL). For example, if the equipment's BIL is 2200kV, the surge arrester's impulse protection level must be ≤1980kV (with a 10% margin).

[0163] Based on the above parameters, surge arrester specifications should be formulated, specifying indicators such as rated voltage, CCOV, PCOV, and energy withstand value.

[0164] Step 105: Based on the dual selection principle of determining the maximum overvoltage of the insulation position determined by the second optimized layout and the second optimized key parameters, the surge arrester is configured.

[0165] Preferably, the dual selection principle for surge arresters, based on the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters, includes:

[0166] Calculate the effective energy absorbed by the surge arrester based on the minimum VI protection characteristics;

[0167] Calculate the range of residual voltage difference values ​​for surge arresters based on the maximum residual voltage deviation characteristics;

[0168] The maximum protection level of the surge arrester is calculated based on the maximum VI protection characteristics.

[0169] This invention identifies overvoltage at insulation locations and clarifies the selection principles for surge arresters:

[0170] First, simulations are used to determine the maximum representative overvoltages at different insulation locations, such as the maximum lightning overvoltage of 2100kV on the converter valve side and the maximum switching overvoltage of 1500kV on the DC bus. When selecting surge arresters, a dual principle must be followed: When calculating energy absorption, the minimum (VI) protection characteristic is used to ensure the arrester can effectively absorb energy (the minimum characteristic results in the lowest residual voltage and the maximum energy absorption); to avoid current shunting, the maximum residual voltage deviation characteristic is used for parallel surge arresters (the maximum residual voltage is higher than the main surge arrester, reducing current shunting); when determining the protection level, the maximum (VI) protection characteristic is used to ensure equipment insulation safety (the maximum residual voltage corresponds to the most stringent protection scenario).

[0171] By dynamically correcting the charge rate, the error caused by the fixed charge rate value in traditional methods is reduced to within ±5%. For example, in ±800kV UHV projects, for surge arresters with CCOV=100kV, the Uref calculation result is corrected from 133.3kV (η=0.75) in the traditional method to 142.9kV (η=0.7), with a deviation of less than 3% from the measured value, significantly improving the reliability of equipment selection. Based on the accurate calculation results of lightning surge voltage, the installation location and number of surge arresters can be optimized. In a certain UHV hybrid cascade converter station, this method limits the valve-side overvoltage to within 1.2 times the rated voltage, a 15% reduction compared to the traditional design, effectively avoiding the risk of lightning strike failures in the station's equipment.

[0172] A typical topology diagram of the hybrid cascaded DC system of the present invention is shown below. Figure 11 As shown in the figure. A typical waveform diagram of the lightning intrusion wave overvoltage of the through-wall bushing in the UHVDC converter station of this invention is shown in the figure. Figure 12 As shown in the figure. This invention calculates the overvoltage across the smoothing reactor and the discharge current of the DR1 surge arrester when the DC filter of the UHV converter station simultaneously shuts down, a negative 20kA lightning current strikes the conductor of tower 3 at pole P1, and is illustrated in the figure. Figure 13 As shown.

[0173] This invention addresses the insufficient accuracy of traditional methods in calculating lightning intrusion waves at ultra-high voltage converter stations through dynamic charge rate correction and numerical calculation, providing reliable technical support for the safe operation of the power grid. This method not only improves calculation accuracy but also optimizes insulation coordination, strengthens thermal stability verification, and reduces engineering costs, demonstrating significant economic and social benefits.

[0174] Figure 14 This is a system structure diagram of a surge arrester configured based on simulation calculation of lightning intrusion wave according to a preferred embodiment of the present invention.

[0175] like Figure 14 As shown, this invention provides a system for configuring surge arresters based on simulation calculations of lightning intrusion waves. The system includes:

[0176] Initial unit 201 is used to determine the initial arrangement and initial key parameters of the surge arresters on the AC and DC sides;

[0177] Preferably, the initial unit 201 is used to determine the initial arrangement and initial key parameters of the AC and DC side surge arresters, wherein,

[0178] The initial key parameters for the communication side include:

[0179] Determine the rated voltage Ur to be ≥ 1.05~1.1×U 工频 ,max (safety margin), U 工频 = K × Un, where Un is the system's rated line voltage, K is the overvoltage multiple (1.3-1.5 for 220kV systems, 1.2-1.4 for 500kV systems), U 工频 ,max (safety margin) is the maximum value of the power frequency voltage; control the leakage current under rated voltage to ≤100μA, and control the distance between the surge arrester on the AC side and the protected equipment to ≤900m;

[0180] The initial key parameters on the DC side include:

[0181] The following conditions must be met: continuous operating voltage CCOV ≥ Uc,max; temporary overvoltage withstand voltage PCOV ≥ Uch,max; where Uch,max is the maximum value of temporary overvoltage and Uc,max is the maximum value of continuous operating voltage; the DC reference voltage Uref = CCOV / η is calculated based on a charge rate of 65%-75%, where η is the charge rate of the surge arrester; the distance between the surge arrester on the DC side and the protected equipment must be ≤900m.

[0182] The first adjustment unit 202 is used to adjust the initial key parameters and initial arrangement based on the temporary overvoltage and the slow wave front overvoltage, and to determine the first optimized key parameters and the first optimized arrangement.

[0183] Preferably, the first adjustment unit 202 is used to adjust the initial key parameters and initial arrangement based on the temporary overvoltage and the soft wavefront overvoltage, and to determine the first optimized key parameters and the first optimized arrangement, including:

[0184] Typical fault conditions were identified, including temporary overvoltage duration of 0.1s-10s and pre-wave overvoltage wavefront time of 50μs-1000μs.

[0185] Based on typical fault conditions, determine the structural parameters of the surge arrester, including: the number of series resistors in the surge arrester, the number of internal valve columns connected in parallel, and the number of external surge arresters connected in parallel.

[0186] When the initial key parameters or initial arrangement do not meet the structural parameters of the surge arrester, the initial key parameters or initial arrangement are adjusted to determine the first optimized key parameters and the first optimized arrangement.

[0187] The second adjustment unit 203 is used to adjust the first optimization key parameters and the first optimization arrangement based on lightning overvoltage and steep wavefront overvoltage, and to determine the second optimization key parameters and the second optimization arrangement.

[0188] Preferably, the second adjustment unit 203 is used to adjust the first optimization key parameters and the first optimization arrangement based on the lightning overvoltage and the steep wavefront overvoltage, and to determine the second optimization key parameters and the second optimization arrangement, including:

[0189] The wavefront time of lightning overvoltage was determined to be 1μs-10μs, the steep wavefront overvoltage, and the target protection area.

[0190] Based on the target protection area and the wavefront time of the lightning overvoltage, simulation calculations are performed to determine the structural parameters of the surge arrester, including the maximum lightning residual voltage and discharge current of the surge arrester.

[0191] When the first optimized key parameters or the first optimized arrangement do not meet the determined structural parameters of the surge arrester, the initial key parameters or the initial arrangement are adjusted to determine the second optimized key parameters and the second optimized arrangement.

[0192] The first determining unit 204 is used to determine the coordination current and protection level of the surge arrester based on the second optimized arrangement and the second optimized key parameters;

[0193] Preferably, the first determining unit 204 is used to determine the coordination current and protection level of the surge arrester based on the determined second optimized arrangement and second optimized key parameters of the surge arrester, including:

[0194] Based on temporary overvoltage, slow-wave front overvoltage, lightning overvoltage, and steep-wave front overvoltage, determine the surge arrester's coordination current, impulse protection level, and energy withstand requirements. Among these requirements, the coordination current shall not be less than the maximum discharge current, the impulse protection level shall not be higher than the equipment insulation withstand reference parameter with a preset margin, and the energy withstand requirement shall be higher than the energy withstand baseline value.

[0195] The second determining unit 205 is used to determine the surge arrester based on the dual selection principle of the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters, and to configure the surge arrester.

[0196] Preferably, the second determining unit 205 is used to determine the dual selection principle of the surge arrester based on the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters, including:

[0197] Calculate the effective energy absorbed by the surge arrester based on the minimum VI protection characteristics;

[0198] Calculate the range of residual voltage difference values ​​for surge arresters based on the maximum residual voltage deviation characteristics;

[0199] The maximum protection level of the surge arrester is calculated based on the maximum VI protection characteristics.

[0200] The present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements steps such as a method for configuring a surge arrester based on a simulation calculation of a lightning intrusion wave.

[0201] This invention provides an electronic device, comprising:

[0202] The aforementioned computer-readable storage medium; and

[0203] One or more processors for executing a program in a computer-readable storage medium.

[0204] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present invention can be implemented using various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0205] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0206] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0207] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0208] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0209] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

[0210] The invention has been described with reference to a few embodiments. However, as will be known to those skilled in the art, and as defined in the appended claims, other embodiments besides those disclosed above fall equivalently within the scope of the invention.

[0211] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the art, unless otherwise expressly defined herein. All references to “a / the / the [device, component, etc.]” ​​are openly interpreted as at least one instance of said device, component, etc., unless otherwise expressly stated. The steps of any method disclosed herein need not be performed in the exact order disclosed unless explicitly stated otherwise.

Claims

1. A method for configuring surge arresters based on simulation calculations of lightning intrusion waves, the method comprising: Determine the initial layout and key parameters of the surge arresters on the AC and DC sides; Based on temporary overvoltage and slow-wave front overvoltage, the initial key parameters and the initial arrangement are adjusted to determine the first optimized key parameters and the first optimized arrangement; Based on lightning overvoltage and steep wavefront overvoltage, the first optimized key parameters and the first optimized arrangement are adjusted to determine the second optimized key parameters and the second optimized arrangement. Based on the second optimized arrangement and the second optimized key parameters, the coordination current and protection level of the surge arrester are determined; Based on the dual selection principle of determining the surge arrester according to the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters, the surge arrester is configured.

2. The method according to claim 1, wherein determining the initial arrangement and initial key parameters of the AC-side and DC-side surge arresters, wherein, The initial key parameters for the communication side include: Determine the rated voltage Ur to be ≥ 1.05~1.1×U 工频 ,max (safety margin), U 工频 = K × Un, where Un is the system's rated line voltage, K is the overvoltage multiple (1.3-1.5 for 220kV systems, 1.2-1.4 for 500kV systems), U 工频 ,max (safety margin) is the maximum value of the power frequency voltage; control the leakage current under rated voltage to ≤100μA, and control the distance between the surge arrester on the AC side and the protected equipment to ≤900m; The initial key parameters on the DC side include: The continuous operating voltage CCOV ≥ Uc,max and the temporary overvoltage withstand voltage PCOV ≥ Uch,max are satisfied. ch ,max is the maximum value of temporary overvoltage, and Uc,max is the maximum value of continuous operating voltage; combined with a charge rate of 65%-75%, the DC reference voltage Uref=CCOV / η is calculated, where η is the charge rate of the surge arrester; the distance between the surge arrester on the DC side and the protected equipment is ≤900m.

3. The method according to claim 2, wherein adjusting the initial key parameters and initial arrangement based on temporary overvoltage and soft-front overvoltage to determine the first optimized key parameters and first optimized arrangement includes: Typical fault conditions are identified, including the duration of the temporary overvoltage of 0.1s-10s and the wavefront time of the slow wavefront overvoltage of 50μs-1000μs. Based on the typical fault conditions, the structural parameters of the surge arrester are determined, including: the number of series resistors in the surge arrester, the number of internal valve columns in parallel, and the number of external surge arresters in parallel. When the initial key parameters or initial arrangement do not meet the structural parameters of the surge arrester, the initial key parameters or initial arrangement are adjusted to determine the first optimized key parameters and the first optimized arrangement.

4. The method according to claim 1, wherein adjusting the first optimized key parameters and the first optimized arrangement based on lightning overvoltage and steep wavefront overvoltage, and determining the second optimized key parameters and the second optimized arrangement, includes: The wavefront time of lightning overvoltage was determined to be 1μs-10μs, the steep wavefront overvoltage, and the target protection area. Based on the target protection area and the determined wavefront time of the lightning overvoltage, simulation calculations are performed to determine the structural parameters of the surge arrester, including: the maximum residual lightning voltage and discharge current of the surge arrester. When the first optimized key parameter or the first optimized arrangement does not meet the determined structural parameters of the surge arrester, the initial key parameter or the initial arrangement is adjusted to determine the second optimized key parameter and the second optimized arrangement.

5. The method according to claim 1, wherein determining the coordination current and protection level of the surge arrester based on the determined second optimized arrangement and second optimized key parameters of the surge arrester includes: Based on temporary overvoltage, slow-wave front overvoltage, lightning overvoltage, and steep-wave front overvoltage, the coordination current, impulse protection level, and energy withstand requirements of the surge arrester are determined, wherein: the coordination current is not less than the maximum discharge current, the impulse protection level is not higher than the equipment insulation withstand reference parameter and a preset margin, and the energy withstand requirement is higher than the energy withstand baseline value.

6. The method according to claim 1, wherein the dual selection principle for determining the surge arrester based on the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters includes: Calculate the effective energy absorbed by the surge arrester based on the minimum VI protection characteristics; Calculate the range of residual voltage difference values ​​for surge arresters based on the maximum residual voltage deviation characteristics; The maximum protection level of the surge arrester is calculated based on the maximum VI protection characteristics.

7. A system for configuring surge arresters based on simulation calculations of lightning intrusion waves, the system comprising: The initial unit is used to determine the initial arrangement and key parameters of the surge arresters on the AC and DC sides. The first adjustment unit is used to adjust the initial key parameters and the initial arrangement based on the temporary overvoltage and the slow wave front overvoltage, and to determine the first optimized key parameters and the first optimized arrangement. The second adjustment unit is used to adjust the first optimization key parameters and the first optimization arrangement based on lightning overvoltage and steep wavefront overvoltage, and to determine the second optimization key parameters and the second optimization arrangement. The first determining unit is used to determine the coordination current and protection level of the surge arrester based on the second optimized arrangement and the second optimized key parameters; The second determining unit is used to configure the surge arrester based on the dual selection principle of determining the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters.

8. The system according to claim 7, wherein the initial unit is used to determine the initial arrangement and initial key parameters of the AC-side and DC-side surge arresters, wherein, The initial key parameters for the communication side include: Determine the rated voltage Ur to be ≥ 1.05~1.1×U 工频 ,max (safety margin), U 工频 = K × Un, where Un is the system's rated line voltage, K is the overvoltage multiple (1.3-1.5 for 220kV systems, 1.2-1.4 for 500kV systems), U 工频 ,max (safety margin) is the maximum value of the power frequency voltage; control the leakage current under rated voltage to ≤100μA, and control the distance between the surge arrester on the AC side and the protected equipment to ≤900m; The initial key parameters on the DC side include: The following conditions must be met: continuous operating voltage CCOV ≥ Uc,max, temporary overvoltage withstand voltage PCOV ≥ Uch,max, and U ch ,max is the maximum value of temporary overvoltage, and Uc,max is the maximum value of continuous operating voltage; combined with a charge rate of 65%-75%, the DC reference voltage Uref=CCOV / η is calculated, where η is the charge rate of the surge arrester; the distance between the surge arrester on the DC side and the protected equipment is controlled to be ≤900m.

9. The system according to claim 8, wherein the first adjustment unit is configured to adjust the initial key parameters and initial arrangement based on temporary overvoltage and soft-front overvoltage, and determine the first optimized key parameters and first optimized arrangement, comprising: Typical fault conditions are identified, including the duration of the temporary overvoltage of 0.1s-10s and the wavefront time of the slow wavefront overvoltage of 50μs-1000μs. Based on the typical fault conditions, the structural parameters of the surge arrester are determined, including: the number of series resistors in the surge arrester, the number of internal valve columns in parallel, and the number of external surge arresters in parallel. When the initial key parameters or initial arrangement do not meet the structural parameters of the surge arrester, the initial key parameters or initial arrangement are adjusted to determine the first optimized key parameters and the first optimized arrangement.

10. The system according to claim 9, wherein the second adjustment unit is configured to adjust the first optimization key parameters and the first optimization arrangement based on lightning overvoltage and steep wavefront overvoltage, and determine the second optimization key parameters and the second optimization arrangement, comprising: The wavefront time of lightning overvoltage was determined to be 1μs-10μs, the steep wavefront overvoltage, and the target protection area. Based on the target protection area and the determined wavefront time of the lightning overvoltage, simulation calculations are performed to determine the structural parameters of the surge arrester, including: the maximum residual lightning voltage and discharge current of the surge arrester. When the first optimized key parameter or the first optimized arrangement does not meet the determined structural parameters of the surge arrester, the initial key parameter or the initial arrangement is adjusted to determine the second optimized key parameter and the second optimized arrangement.

11. The method according to claim 10, wherein the first determining unit is configured to determine the coordination current and protection level of the surge arrester based on the determined second optimized arrangement and second optimized key parameters of the surge arrester, comprising: Based on temporary overvoltage, slow-wave front overvoltage, lightning overvoltage, and steep-wave front overvoltage, the coordination current, impulse protection level, and energy withstand requirements of the surge arrester are determined, wherein: the coordination current is not less than the maximum discharge current, the impulse protection level is not higher than the equipment insulation withstand reference parameter and a preset margin, and the energy withstand requirement is higher than the energy withstand baseline value.

12. The system according to claim 10, wherein the second determining unit is configured to determine a dual selection principle for the surge arrester based on the maximum overvoltage of the insulation position determined by the second optimized arrangement and the second optimized key parameters, comprising: Calculate the effective energy absorbed by the surge arrester based on the minimum VI protection characteristics; Calculate the range of residual voltage difference values ​​for surge arresters based on the maximum residual voltage deviation characteristics; The maximum protection level of the surge arrester is calculated based on the maximum VI protection characteristics.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the method as described in any one of claims 1-6.

14. An electronic device, characterized in that, include: The computer-readable storage medium as described in claim 13; as well as One or more processors for executing a program in the computer-readable storage medium.

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