Photovoltaic array interference calculation method, device and system under lightning impulse

Abstract

The invention discloses a method, a device and a system for calculating photovoltaic array interference under lightning impulse. A proper lightning current waveform is selected, and key parameters of the lightning current waveform are determined, so that authenticity and accuracy of the simulated lightning environment are ensured; based on the attribute parameters of the photovoltaic module, establishing an electrical equivalent model of the photovoltaic array; calculating a transient induced voltage and a transient interference current in the lightning product photovoltaic array by using the electrical equivalent model and the lightning current waveform so as to evaluate the potential influence of lightning impulse on the photovoltaic array; the problem that the electromagnetic interference calculation method of the new energy cable under the lightning impulse is often too simplified and cannot accurately reflect the actual situation is solved, powerful support is provided for safety protection and performance optimization of a photovoltaic system, and the stability and reliability of the photovoltaic system in the lightning environment can be improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of safety protection of photovoltaic power generation systems, and relates to a method, device and system for calculating interference of photovoltaic arrays under lightning impulse. Background Art

[0002] As the world pays more and more attention to environmental protection and sustainable development, the new energy industry has ushered in unprecedented development opportunities. As a key component of power transmission, new energy cables play a vital role in the grid connection and distribution of renewable energy such as wind power and solar energy. New energy cables are not only required to have efficient and safe power transmission capabilities, but also need to adapt to complex and changing operating environments to ensure the stability and reliability of power supply.

[0003] However, in practical applications, new energy cables face various forms of impact challenges, which mainly come from mechanical stress and drastic changes in the electrical environment. Mechanical shocks may come from factors such as the rotation of wind turbine blades, seismic activity or human construction, while electrical shocks may include lightning strikes, short-circuit currents and other transient overvoltage events in the power system. These shocks may not only directly damage the physical structure of the cable, but more importantly, they will generate complex electromagnetic fields around and inside the cable, causing electromagnetic interference (EMI), which in turn affects the efficiency and quality of power transmission, and in severe cases even causes system failure or paralysis.

[0004] At present, the industry mainly relies on some simplified theoretical models and numerical methods to calculate the electromagnetic interference of new energy cables under impact conditions. Although these traditional methods can provide some qualitative analysis results to a certain extent, their calculation results often deviate greatly from the actual situation because they fail to fully consider the cable material characteristics, structural complexity and dynamic changes in the actual operating environment. For example, the simplified model may ignore the role of the cable shielding layer, the nonlinear effect of the insulation material and the electromagnetic compatibility of the surrounding environment, resulting in inaccurate prediction of electromagnetic interference, making it difficult to effectively guide the design and optimization of cables and formulate targeted protective measures. Summary of the invention

[0005] The purpose of the present invention is to solve the technical problem that the electromagnetic interference calculation method of new energy cables under lightning strikes in the prior art is often too simplified and cannot accurately reflect the actual situation, resulting in inaccurate cable design and protective measures, and to provide a method, device and system for calculating the interference of photovoltaic arrays under lightning strikes.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A first aspect of the present invention provides a method for calculating interference of a photovoltaic array under a lightning impulse, comprising the following steps: Select the lightning current waveform and determine the lightning current parameters; Based on the attribute parameters of the photovoltaic modules, establish the electrical equivalent model of the photovoltaic array; Based on the electrical equivalent model of the photovoltaic array and the lightning current parameters, calculate the transient induced voltage and transient interference current in the lightning-struck photovoltaic array.

[0007] Furthermore, the selection of the lightning current waveform and determination of the lightning current parameters are specifically as follows: Based on the selected lightning current waveform, describe the lightning current waveform using a double-exponential function; According to the lightning current waveform, determine the lightning current parameters, where the lightning current parameters include peak current, charge quantity, front time, and tail time.

[0008] Furthermore, the electrical equivalent model of the photovoltaic array includes a photovoltaic support model, a photovoltaic panel model, a junction box model, an inverter model, and a busbar model.

[0009] Furthermore, the electrical equivalent model of the photovoltaic array uses slender conductors to perform equivalent modeling on the photovoltaic system.

[0010] Furthermore, the calculation of the transient induced voltage and transient interference current in the lightning-struck photovoltaic array based on the electrical equivalent model of the photovoltaic array and the lightning current parameters is specifically as follows: Convert the lightning current waveform into a lightning current spectrum using Fourier transform while satisfying the sampling theorem; Select frequency points according to the lightning current spectrum; Calculate the unit frequency domain response of the transient induced voltage and transient interference current of each section of the conductor at each frequency point; Multiply the unit frequency domain response of the conductor at each frequency point by the lightning current spectrum, and at the same time use inverse Fourier transform to obtain the transient induced voltage and transient interference current of each section of the conductor; Based on the transient induced voltage and transient interference current of each section of the conductor, calculate the transient induced voltage and transient interference current in the lightning-struck photovoltaic array.

[0011] Furthermore, the calculation of the unit frequency domain response of the transient induced voltage and transient interference current of each section of the conductor at each frequency point is specifically as follows: Based on the electrical equivalent model of the photovoltaic array, divide the photovoltaic array into several sections of conductors; Calculate the unit frequency domain response of the transient induced voltage and transient interference current of each section of the conductor at each frequency point.

[0012] Furthermore, the transient interference current of each section of the conductor is described as:

[0013] where, is the transient induced voltage of the conductor, which is equal to the external electric field strength at the midpoint of the conductor segment equal; is the k internal self-impedance of the th

[0014] Furthermore, at the connection of conductors with different radii or at the intersection of multiple conductors, the transient interference current is described as:

[0015] wherein, is the conductor radius, is the Euler constant, is the total charge at the intersection, is the conductor length, and the current distribution on each conductor segment is approximated by trigonometric functions, specifically: ; By using the current continuity and charge continuity equations, the relationships among A , B , C and are obtained.

[0016] The second aspect of the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the above-mentioned lightning impulse interference calculation method for a photovoltaic array is implemented.

[0017] The third aspect of the present invention provides a lightning impulse interference calculation system for a photovoltaic array, including: A lightning current module, configured to select a lightning current waveform and determine lightning current parameters; An electrical equivalent module, configured to establish an electrical equivalent model of the photovoltaic array based on the attribute parameters of the photovoltaic modules; An interference calculation module, configured to calculate the transient induced voltage and transient interference current in the photovoltaic array under lightning impact based on the electrical equivalent model of the photovoltaic array and the lightning current waveform.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a method for calculating the interference of a photovoltaic array under lightning impulse. A representative lightning current waveform is selected, and its key parameters, such as peak current, waveform duration, etc., are accurately determined, ensuring the authenticity and accuracy of the simulated lightning strike event. Subsequently, based on the detailed attribute parameters of the photovoltaic modules, an electrical equivalent model of the photovoltaic array is constructed, which can truly reflect the electrical behavior of the photovoltaic array under lightning impulse. Through these precise data and models, this method can accurately calculate the transient induced voltage and transient interference current in the photovoltaic array under lightning strike, providing a reliable basis for evaluating the potential damage of lightning strikes to the photovoltaic array; through the calculation of the interference of the photovoltaic array under lightning impulse, the electrical response of the photovoltaic array under lightning impulse can be deeply understood, and then potential vulnerable links and safety hazards can be identified. This helps to take corresponding protective measures, such as adding lightning rods, optimizing the array layout, etc., in the design stage to effectively reduce the risk of damage to the photovoltaic system caused by lightning strikes. At the same time, this method can also provide valuable reference information for the operation and maintenance personnel of the photovoltaic system, helping the operation and maintenance personnel to discover and handle potential safety problems in a timely manner during daily operation and maintenance, thereby improving the overall safety and reliability of the photovoltaic system.

[0019] Furthermore, since a photovoltaic array is usually composed of a large number of slender photovoltaic modules and connecting wires, these modules and connecting wires will exhibit complex electromagnetic coupling effects under lightning impulse. By using slender conductor modeling, the electrical characteristics of these modules and connecting wires can be more finely described, thus more accurately predicting the impact of lightning impulse on the photovoltaic array. At the same time, the slender conductor model can simplify the electrical structure of the photovoltaic array, reduce the computational complexity, and maintain a high computational accuracy. It can quickly obtain key parameters such as the transient induced voltage and transient interference current of the photovoltaic array under lightning impulse with limited computational resources, providing timely and effective support for the safety protection and performance optimization of the photovoltaic system.

[0020] Furthermore, by converting the lightning current waveform into a spectrum and selecting key frequency points for calculation, this method can capture the high-frequency components of the transient induced voltage and transient interference current in the photovoltaic array under lightning impulse, thereby improving the calculation accuracy. At the same time, by using Fourier transform and inverse transform, the conversion from the frequency domain to the time domain is realized, making the calculation results more intuitive and easy to understand. Based on the electrical equivalent model of the photovoltaic array, this method divides the photovoltaic array into several sections of conductors and calculates the unit frequency domain response of the transient induced voltage and transient interference current of each section of conductor respectively. This way of segmented processing not only simplifies the calculation process but also improves the calculation efficiency, especially suitable for dealing with photovoltaic arrays with complex electrical structures. At the connection points of conductors with different radii or at the intersections of multiple conductors, by introducing the charge continuity and current continuity equations, the electromagnetic coupling effect between conductors is accurately described. This helps to more accurately evaluate the mutual influence between conductors in the photovoltaic array under lightning impulse.

[0021] Furthermore, the present invention proposes a photovoltaic array interference calculation system under lightning impulse. The lightning current module can accurately select the lightning current waveform and determine its key parameters, such as peak current, waveform duration, etc. This ensures the authenticity and accuracy of the simulated lightning environment and provides a reliable basis for subsequent calculations. The electrical equivalent module can quickly establish an electrical equivalent model of the photovoltaic array based on the attribute parameters of the photovoltaic modules. This model can truly reflect the electrical behavior of the photovoltaic array under lightning impulse and provides an accurate electrical structure for subsequent interference calculations. The interference calculation module can accurately calculate the transient induced voltage and transient interference current in the photovoltaic array using the electrical equivalent model and the lightning current waveform. These calculation results are of great significance for evaluating the potential damage of lightning impulse to the photovoltaic array and formulating protection measures. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0023] Figure 1 It is a block diagram of the photovoltaic array interference calculation method under lightning impulse of the present invention; Figure 2 It is a block diagram of the photovoltaic array interference calculation system under lightning impulse of the present invention; Figure 3 It is a typical lightning current waveform diagram; Figure 4 It is a model diagram of a photovoltaic support; Figure 5 It is a model diagram of a photovoltaic panel; Figure 6 It is a single diode equivalent model diagram of a photovoltaic cell; Figure 7 It is a transient model diagram of a photovoltaic cell; Figure 8 It is a model diagram of a busbar box; Figure 9 It is a model diagram of an inverter; Figure 10 It is a model diagram of a busbar line.

[0024] Among them: 1 - insulating layer; 2 - core wire; 3 - shielding layer; 4 - sheath. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and marked in the accompanying drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0027] It should be noted that: like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not require further definition and explanation in subsequent drawings.

[0028] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the inventive product is usually placed during use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive distinction and cannot be construed as indicating or implying relative importance.

[0029] In addition, if the term "horizontal" appears, it does not mean that the component is required to be absolutely horizontal, but it can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but it can be slightly inclined.

[0030] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "connected to" are understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] The following further describes the present invention in detail with reference to the accompanying drawings: See Figure 1, The present invention discloses a method for calculating the interference of a photovoltaic array under lightning impulse, which includes the following steps: S1, Select the lightning current waveform and determine the lightning current parameters; according to the specific application scenario and required accuracy, select the lightning current waveform, and at the same time use the double-exponential function to describe the lightning current waveform; the double-exponential function can better simulate the waveform characteristics of the actual lightning impulse, including the changes in the front time and the tail time; then the lightning current waveform is described as:

[0032] In the formula, is the peak value of the lightning current ， is the front attenuation coefficient ， is the tail attenuation coefficient, is the instantaneous value of the lightning current; The lightning current waveform parameters are selected according to the relevant IEC standards, as shown in the following table:

[0033] Through the above lightning current waveform, determine the lightning current parameters: Peak current: Set based on the common lightning impulse intensity.

[0034] Charge quantity: Obtained by integrating the lightning current waveform, representing the total charge transmitted during the lightning impulse process.

[0035] Front time: Represents the time required for the lightning current to rise from 0 to the peak value.

[0036] Tail time: Represents the time required for the lightning current to decay from the peak value to half of it.

[0037] S2, Based on the attribute parameters of the photovoltaic module, establish an electrical equivalent model of the photovoltaic array; the electrical equivalent model of the photovoltaic array includes a photovoltaic support model, a photovoltaic panel model, a junction box model, an inverter model, and a busbar model; the electrical equivalent model of the photovoltaic array uses slender conductors to equivalently model the photovoltaic system.

[0038] The photovoltaic support usually uses C-shaped steel as the support material. Since the C-shaped steel structure is irregular and the thickness of the C-shaped steel is very small, the influence on the propagation of electromagnetic waves can be ignored. In the present invention, the conductors in the photovoltaic support are all regarded as cylindrical conductors, and a photovoltaic support model is constructed, as Figure 4 shown. Therefore, in the photovoltaic support model, the equivalent radius is mainly affected by its edge width, and the expression is as follows:

[0039] Among them, is the width of the C-shaped steel. In this embodiment, the width of the C-shaped steel is 40 mm.

[0040] A photovoltaic panel model, as Figure 5 shown, is used to simulate the electrical characteristics of a photovoltaic panel based on the attribute parameters of the photovoltaic module (such as open-circuit voltage, short-circuit current, internal resistance, and parallel resistance).

[0041] A single photovoltaic panel is composed of multiple photovoltaic cells connected in series by soldering tapes. The circuit model of a photovoltaic cell is usually represented by a single-diode model, a double-diode model, and an improved three-diode equivalent circuit model. In this embodiment, the single-diode model is used to represent the equivalent circuit of the photovoltaic cell, as Figure 6 shown; where represents the photocurrent, where represents the contact resistance between the battery cells and the connecting wires of the battery cells, and represents the diffusion resistance of the semiconductor.

[0042] When a lightning current invades the photovoltaic panel, the photocurrent can be ignored compared with the lightning current amplitude, and the branch where it is located is regarded as an open circuit; the semiconductor diode is regarded as a short circuit under lightning transient; the inductance of the connecting busbar between the battery cell units cannot be ignored under high-frequency transient, and a series inductor is added to the equivalent circuit to represent the inductance of the soldering tape; the resistance is retained to represent the contact resistance between the battery cells and the connecting wires of the battery cells. Then, the lightning transient model of the photovoltaic cell is as Figure 7 shown.

[0043] In this embodiment, the photovoltaic cells in the photovoltaic panel are generally connected by galvanized copper. The selected parameters of the soldering tape are shown in the following table:

[0044] Since the thickness of the soldering tape is relatively thin, the skin effect can be ignored in the modeling of the soldering tape. The resistance of the wire is approximately the DC resistance and can be described as:

[0045] where is the resistivity, is the length; is the area; The inductance is almost equal to the DC inductance and can be calculated using the Hall formula:

[0046]

[0047] where w is the width of the soldering tape, l is the length of the soldering tape,μ 0 is the magnetic permeability in vacuum.

[0048] The combiner box model, a key component in the photovoltaic system of the combiner box, is used to collect the output currents of multiple photovoltaic modules and, through protection devices and control equipment, deliver the current to the inverter for processing, playing a role of centralized connection, protection, and control in the photovoltaic system. In this embodiment, a 16-in-1 type combiner box is adopted, and the model diagram is as Figure 8 shown. The inverter model is used to convert direct current into alternating current and simulate the output characteristics of the photovoltaic system. After multiple paths of electric energy return through the combiner box, they are then sent into the inverter for inversion. After converting the direct current into alternating current, it is sent to the booster station for boosting and then grid-connected. What this invention mainly concerns is the lightning overvoltage level invading the inverter, and the focus of the research is not on the transient response of the power electronic devices in the inverter under lightning strikes. Therefore, the inverter model is similar to the combiner box model and is also composed of a housing, busbars, and outgoing cables, as Figure 9 shown.

[0049] The busbar line model is used to simulate the wire for current transmission in the photovoltaic array. The busbar cable of the photovoltaic mainly consists of a core wire, an insulating layer, a shielding layer, and a cable sheath. When the lightning current invades the photovoltaic system through the lightning rod, a large transient potential will be generated on the bracket. The busbar cable is relatively close to the bracket, which may cause discharge and damage the insulation of the cable. When modeling the busbar cable, the cable is equivalent to a long straight conductor. At the same time, according to the actual physical structure of the cable, the conductor is divided into four layers: the core wire, the insulating layer, the shielding layer, and the sheath, and the structure is as Figure 10 shown.

[0050] S3. Based on the electrical equivalent model of the photovoltaic array and the lightning current waveform, calculate the transient induced voltage and transient interference current in the lightning-struck photovoltaic array.

[0051] S301. Convert the lightning current waveform into a lightning current spectrum using Fourier transform while satisfying the sampling theorem; select a lightning current waveform according to actual needs, and this waveform usually has characteristics of high peak current and rapid decay. To satisfy the sampling theorem, ensure that the sampling frequency is at least twice the highest frequency component of the lightning current waveform. Then, use Fourier transform to convert the lightning current waveform from the time domain to the frequency domain to obtain the lightning current spectrum.

[0052] S302. Select frequency points according to the lightning current spectrum; in the obtained lightning current spectrum, select a series of frequency points for analysis, and the selection of these frequency points should cover the main energy distribution range of the lightning current spectrum to ensure the accuracy of the calculation.

[0053] S303. Calculate the unit frequency domain response of the transient induced voltage and transient interference current of each section of the conductor at each frequency point; Based on the electrical equivalent model of the photovoltaic array, the photovoltaic array is divided into several segments of conductors; Calculate the unit frequency domain response of the transient induced voltage and transient interference current of each segment of conductor at each frequency point. The transient interference current of each segment of conductor is described as:

[0054] Among them, is the transient induced voltage of the conductor, which is equal to the external electric field strength at the midpoint of the conductor segment ; is the internal self-impedance of the k th segment of conductor;

[0055] Among them, is the axial direction of the axis of the cylindrical conductor line current; is the axial current; represents the vector magnetic potential generated by the gradient of the current when the conductor axis length is used as a variable; is the magnetic permeability of the space where the conductor is located; is the permittivity of the space where the conductor is located; k is the wave number.

[0056] At the connection of conductors with different radii or at the intersection of multiple conductors, the transient interference current is described as:

[0057] Among them, is the conductor radius, is the Euler constant, is the total charge at the intersection, is the conductor length, and the current distribution on each segment of conductor is approximated by a trigonometric function and described as: ; By using the current continuity and charge continuity equations, the relationship between A , B , C and is obtained.

[0058] The entire conductor structure is segmented into N segments of conductors, and thus the transient interference voltage of the entire conductor can be obtained:

[0059] Among them is the transfer impedance between the i th segment of conductor and the k th segment of conductor; Based on the transient interference voltage of the entire conductor, the transient interference current of the entire conductor can be obtained:

[0060] The photovoltaic external excitation source usually adopts a current source. When a conductor is connected to the current source, the current at one end of the conductor is a known quantity, that is, the left side of the above formula I Part of the current in is known. By moving the known partial current term to the right side of the equation, other unknown currents (the transient interference current of the entire conductor) can be obtained.

[0061] S304, multiply the unit frequency domain response of the conductor at each frequency point by the lightning current spectrum, and at the same time use the inverse Fourier transform to obtain the time domain responses of the transient induced voltage and transient interference current of each section of the conductor.

[0062] See Figure 2 , the present invention provides a photovoltaic array interference calculation system under lightning impulse, including: A lightning current module, configured to select a lightning current waveform and determine lightning current parameters; An electrical equivalent module, configured to establish an electrical equivalent model of a photovoltaic array based on the attribute parameters of photovoltaic modules; An interference calculation module, configured to calculate the transient induced voltage and transient interference current in the lightning-struck photovoltaic array based on the electrical equivalent model of the photovoltaic array and the lightning current waveform.

[0063] An embodiment of the present invention provides an electronic device, including a processor and a memory. The memory is used to store a computer program, and the computer program includes program instructions. The processor is used to execute the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, and is suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions to implement the process of the method for calculating the interference of a photovoltaic array under lightning impulse or the corresponding function.

[0064] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for calculating the interference of a photovoltaic array under lightning impulse, characterized in that, It includes the following steps: Select a lightning current waveform and determine lightning current parameters; Based on the attribute parameters of photovoltaic modules, establish an electrical equivalent model of the photovoltaic array; Based on the electrical equivalent model of the photovoltaic array and the lightning current parameters, calculate the transient induced voltage and transient interference current in the photovoltaic array under lightning strike.

2. The lightning impulse interference calculation method for a photovoltaic array according to claim 1, wherein The selection of the lightning current waveform and determination of the lightning current parameters are specifically as follows: Based on the selected lightning current waveform, describe the lightning current waveform using a double-exponential function; According to the lightning current waveform, determine the lightning current parameters, where the lightning current parameters include peak current, charge quantity, front time, and tail time.

3. The lightning impulse interference calculation method for a photovoltaic array according to claim 1, wherein The electrical equivalent model of the photovoltaic array includes a photovoltaic support model, a photovoltaic panel model, a busbar box model, an inverter model, and a busbar line model.

4. The method for calculating the interference of a photovoltaic array under lightning impulse according to claim 1, wherein The electrical equivalent model of the photovoltaic array uses a slender conductor to perform equivalent modeling on the photovoltaic system.

5. The lightning impact photovoltaic array interference calculation method according to claim 1, characterized in that, The calculation of the transient induced voltage and transient interference current in the photovoltaic array under lightning strike based on the electrical equivalent model of the photovoltaic array and the lightning current parameters is specifically as follows: Convert the lightning current waveform into a lightning current spectrum using Fourier transform while satisfying the sampling theorem; Select frequency points according to the lightning current spectrum; Calculate the unit frequency domain response of the transient induced voltage and transient interference current of each section of the conductor at each frequency point; Multiply the unit frequency domain response of the conductor at each frequency point by the lightning current spectrum, and at the same time use inverse Fourier transform to obtain the transient induced voltage and transient interference current of each section of the conductor; According to the transient induced voltage and transient interference current of each section of the conductor, calculate the transient induced voltage and transient interference current in the photovoltaic array under lightning strike.

6. The lightning impulse interference calculation method for a photovoltaic array according to claim 5, wherein The calculation of the unit frequency domain response of the transient induced voltage and transient interference current of each section of the conductor at each frequency point is specifically as follows: Based on the electrical equivalent model of the photovoltaic array, divide the photovoltaic array into several sections of conductors; Calculate the unit frequency domain response of the transient induced voltage and transient interference current of each section of the conductor at each frequency point.

7. The lightning impulse interference calculation method for a photovoltaic array according to claim 6, wherein The transient interference current of each section of the conductor is described as: Wherein, is the transient induced voltage of the conductor, which is equal to the external electric field strength at the midpoint of the conductor segment ; is the internal self-impedance of the k th conductor segment.

8. The lightning impulse interference calculation method for a photovoltaic array according to claim 6, characterized in that, At the connection of conductors with different radii or the intersection of multiple conductors, the transient interference current is described as: wherein, is the conductor radius, is the Euler's constant, is the total charge at the intersection point, is the conductor length, and the current distribution on each conductor segment is approximated by trigonometric functions, specifically: ; by using the current continuity and charge continuity equations, the relationships among A , B , C and are obtained.

9. An electronic device, characterized in that, It includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the method for calculating interference in a photovoltaic array under lightning strike according to any one of claims 1-7.

10. A photovoltaic array interference calculation system under lightning impulse, characterized in that, It includes: A lightning current module for selecting a lightning current waveform and determining lightning current parameters; An electrical equivalent module for establishing an electrical equivalent model of the photovoltaic array based on the attribute parameters of photovoltaic modules; An interference calculation module for calculating the transient induced voltage and transient interference current in the photovoltaic array under lightning strike based on the electrical equivalent model of the photovoltaic array and the lightning current waveform.

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