A method and device for analyzing fire spread parameters of photovoltaic modules

Abstract

The present invention discloses a method and device for analyzing fire spread parameters of photovoltaic modules, belonging to the field of photovoltaic power generation technology, including: S1, obtaining basic data; including environmental parameters, material properties and combustion characteristics of photovoltaic modules; material properties including thermal conductivity, density and specific heat capacity; combustion characteristics including combustion heat and initial temperature; environmental parameters including wind speed, ambient temperature and humidity; S2, analyzing fire spread parameters through the basic data; S201, constructing a thermal diffusivity calculation model; S202, calculating flame spread speed based on the thermal diffusivity calculation model; S203, correcting the flame spread speed using environmental parameters; S204, calculating the fire spread distance based on the corrected flame spread speed. The present invention comprehensively considers the material properties, combustion characteristics and environmental factors of photovoltaic modules, can accurately predict the speed and range of fire spread, and thus provides a scientific basis for the fire protection design of photovoltaic power stations.

Description

Technical Field

[0001] The present invention belongs to the technical field of photovoltaic power generation, and in particular relates to a method and a device for analyzing fire spread parameters of photovoltaic modules. Background Art

[0002] Globally, energy demand is showing a continuous upward trend. At the same time, people's awareness of environmental protection is also awakening. As a green, clean and renewable energy source, photovoltaic power generation has gradually become more prominent and has received widespread attention and rapid development worldwide. Photovoltaic modules, as an important part of photovoltaic power generation systems, have been widely used in residential, commercial buildings, large photovoltaic power stations and other fields. However, when photovoltaic modules are affected by high temperature, mechanical damage, etc., they may cause fires, which not only threaten people's lives and safety, but also cause property losses. Therefore, it is of great significance to deeply study the spread of photovoltaic module fires and develop effective fire warning and prevention and control technologies.

[0003] Most traditional fire spread models are based on the fire characteristics of building materials, but this is not targeted at photovoltaic modules. Photovoltaic modules have their own unique material properties and combustion characteristics, which makes the fire spread behavior of photovoltaic modules particularly complex and special. Therefore, in order to accurately predict the spread speed and distance of photovoltaic module fires and formulate scientific and reasonable fire prevention measures, it is particularly important to develop an analysis method and device for photovoltaic module fire spread parameters. Summary of the invention

[0004] The purpose of the present invention is to meet practical needs and provide a method and device for analyzing the fire spread parameters of photovoltaic modules, which comprehensively considers the material properties, combustion characteristics and environmental factors of photovoltaic modules, and can accurately predict the speed and scope of fire spread, thereby providing a scientific basis for the fire protection design of photovoltaic power stations.

[0005] The first object of the present invention is to provide a method for analyzing fire spread parameters of photovoltaic modules, comprising:

[0006] S1. Obtain basic data; the basic data includes environmental parameters, material properties and combustion characteristics of photovoltaic modules; the material properties include thermal conductivity, density and specific heat capacity; the combustion characteristics include combustion heat and initial temperature; the environmental parameters include wind speed, ambient temperature and humidity;

[0007] S2. Analyze the fire spread parameters based on the basic data; specifically include:

[0008] S201, constructing a thermal diffusivity calculation model;

[0009] S202, calculating the flame spread speed based on the thermal diffusivity calculation model;

[0010] S203, using environmental parameters to correct the flame spread speed;

[0011] S204. Calculate the fire spread distance based on the corrected flame spread speed.

[0012] Preferably, in S201, the expression of the thermal diffusivity calculation model is:

[0013]

[0014] Where: T is the temperature of the photovoltaic module, t is the time, α is the thermal diffusivity, λ is the thermal conductivity, ρ is the density of the photovoltaic module, c p is the specific heat capacity of the photovoltaic module, is the Laplace operator.

[0015] Preferably, in S202, the flame spread speed calculation formula is:

[0016]

[0017] Where: S f is the flame spread speed, ΔH is the combustion heat of the photovoltaic module, and T0 is the initial temperature.

[0018] Preferably, in S203, the correction formula is:

[0019] S corr =S f ×f(v,T a , H)

[0020] f(v,T a , H)=1+a v v+a T (T a -T0)-a H H

[0021] S corr is the corrected flame spread speed, v is the wind speed, T a is the ambient temperature, H is the humidity, f is the correction function, a v is the wind speed coefficient, a T is the temperature coefficient, a H is the humidity coefficient.

[0022] Preferably, in S204, the calculation formula for the fire spread distance is:

[0023] D is the flame spread distance.

[0024] A second object of the present invention is to provide a device for analyzing fire spread parameters of photovoltaic modules, comprising:

[0025] Data collection module: obtaining basic data; the basic data includes environmental parameters, material properties of photovoltaic modules and combustion characteristics; the material properties include thermal conductivity, density and specific heat capacity; the combustion characteristics include combustion heat and initial temperature; the environmental parameters include wind speed, ambient temperature and humidity;

[0026] Data analysis module: analyzes fire spread parameters through the basic data; specifically includes:

[0027] Model building unit: building a thermal diffusivity calculation model;

[0028] Speed ​​analysis unit: calculates the flame spread speed based on the thermal diffusivity calculation model;

[0029] Speed ​​correction unit: Use environmental parameters to correct the flame spread speed;

[0030] Distance analysis unit: Calculates the fire spread distance based on the corrected flame spread speed.

[0031] Preferably, the thermal diffusivity calculation model is expressed as:

[0032]

[0033] Where: T is the temperature of the photovoltaic module, t is the time, α is the thermal diffusivity, λ is the thermal conductivity, ρ is the density of the photovoltaic module, c p is the specific heat capacity of the photovoltaic module, is the Laplace operator;

[0034] Flame spread speed calculation formula:

[0035]

[0036] Where: S f is the flame spread speed, ΔH is the combustion heat of the photovoltaic module, and T0 is the initial temperature;

[0037] The correction formula for flame spread speed is:

[0038] S corr =S f ×f(v,T a , H)

[0039] f(v,T a , H)=1+a v v+a T (T a -T0)-a H H

[0040] S corr is the corrected flame spread speed, v is the wind speed, T a is the ambient temperature, H is the humidity, f is the correction function, a v is the wind speed coefficient, a T is the temperature coefficient, a H is the humidity coefficient;

[0041] The formula for calculating the fire spread distance is:

[0042]

[0043] D is the flame spread distance.

[0044] A third object of the present invention is to provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-mentioned method for analyzing fire spread parameters of photovoltaic modules.

[0045] A fourth object of the present invention is to provide a computer program product, comprising a computer program, which, when executed by a processor, implements the above-mentioned method for analyzing fire spread parameters of photovoltaic modules.

[0046] The advantages and positive effects of this application are:

[0047] The present invention can accurately predict the spread speed and distance of a photovoltaic module fire, thereby providing an effective fire isolation zone and fire extinguishing system for the design of a photovoltaic power station, so as to reduce the impact of the fire on the normal operation of the power station and ensure the safe operation of the power station. Based on the technical solution of the present invention, a scientific basis can be provided for the fire prevention design of a photovoltaic power station, making the fire prevention measures more targeted and effective.

[0048] By preventing and controlling the spread of fires in advance, the economic losses caused by fires in photovoltaic power plants can be effectively reduced and the economic benefits of power plants can be improved. The safe and reliable operation of photovoltaic power plants is the cornerstone of the healthy development of the photovoltaic industry. By improving the fire prevention and control capabilities of photovoltaic power plants, industry confidence can be enhanced and the sustainable development of the photovoltaic industry can be promoted. Specifically:

[0049] The present invention comprehensively considers the material properties of photovoltaic modules and establishes a thermal diffusivity calculation model based on the material properties of photovoltaic modules, which can accurately simulate the heat transfer behavior of photovoltaic modules under fire conditions. Traditional methods usually ignore the specific material properties of photovoltaic modules, while the present invention introduces the thermal conductivity, density and specific heat capacity of photovoltaic modules to construct a more accurate heat conduction equation and improve the calculation accuracy.

[0050] The present invention uses the combustion heat and initial temperature in combustion theory to calculate the flame spread speed on the surface of the photovoltaic module. Unlike existing methods, the present invention incorporates the combustion characteristics of the photovoltaic module into the calculation model, and by calculating the flame spread speed, it is closer to the combustion process in the actual fire scene.

[0051] The present invention considers the correction method of environmental factors (wind speed, temperature, humidity) on the flame spread speed, and forms a dynamic flame spread speed calculation model. Traditional fire spread models usually ignore environmental influences, but the present invention establishes an environmental correction function through experimental data fitting, so that the model can be dynamically adjusted according to actual environmental conditions, improving the adaptability and practicality of the model.

[0052] The present invention uses a method for calculating the fire spread distance by time integration to predict the spread range of a fire within a given time. Specifically, the present invention proposes a simple and effective time integration method to calculate the spread distance of a fire within a specific time period based on the corrected flame spread speed, providing a scientific basis for the formulation of fire prevention measures.

[0053] The present invention integrates the thermal diffusion rate calculation model and environmental factor correction to form a high-precision fire spread speed and distance prediction algorithm. Compared with the existing simple prediction model, the present invention can provide a higher-precision fire spread prediction, which is suitable for fire risk assessment and prevention and control in actual photovoltaic power plants and has significant practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0055] Figure 1 shows an overall flow chart provided by an embodiment of the present invention;

[0056] Figure 2 A flow chart of the S2 part provided in an embodiment of the present invention is shown;

[0057] Figure 3 A structural block diagram of a device provided by an embodiment of the present invention is shown;

[0058] Figure 4 The structure block diagram of the data analysis module provided by the embodiment of the present invention is shown. DETAILED DESCRIPTION

[0059] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0060] First embodiment

[0061] The present invention provides a method for analyzing fire spread parameters of photovoltaic modules, such as Figure 1 and Figure 2 As shown, the following steps are included:

[0062] S1. Obtain basic data;

[0063] The basic data include both the material properties and combustion characteristics of the photovoltaic modules and the environmental parameters; among which:

[0064] The material properties mainly include thermal conductivity, density and specific heat capacity;

[0065] The combustion characteristics mainly include combustion heat and initial temperature;

[0066] The environmental parameters mainly include wind speed, ambient temperature and humidity;

[0067] S2. Analyze the fire spread parameters based on the basic data; specifically include:

[0068] S201, construct a thermal diffusivity calculation model; substitute the Fourier heat conduction model into the energy conservation equation to determine the heat conduction formula, and at the same time obtain the thermal diffusion coefficient solution model.

[0069]

[0070] The thermal diffusivity calculation model is as follows:

[0071]

[0072] Where: T is the temperature of the photovoltaic module (K), t is the time (s), α is the thermal diffusivity (m 2 / s), λ is the thermal conductivity (W / m·K), ρ is the density of the photovoltaic module (kg / m 3 ), c p is the specific heat capacity of the photovoltaic module (J / kg·K), is the Laplace operator.

[0073] S202, calculating the flame spread speed based on the thermal diffusivity calculation model;

[0074] Flame spread speed calculation formula:

[0075]

[0076] Where: S f is the flame spread speed (m / s), ΔH is the combustion heat of the PV module (J / kg), and T0 is the initial temperature (K).

[0077] S203. Correct the flame spread speed using environmental parameters; the correction formula is:

[0078] S corr =S f ×f(v,T a , H)

[0079] f(v,T a , H)=1+a v v+a T (T a -T0)-a H H

[0080] S corr is the corrected flame spread speed (m / s), v is the wind speed (m / s), T a is the ambient temperature (K), H is the humidity (%). f is the correction function, a v is the wind speed coefficient (value is 0.1), a T is the temperature coefficient (value is 0.05), a H is the humidity coefficient (the value is 0.02).

[0081] S204, calculating the fire spread distance based on the corrected flame spread speed;

[0082] The fire spread distance formula is:

[0083]

[0084] Where D is the flame spread distance (m) and t is the time (s).

[0085] An analysis device for fire spread parameters of photovoltaic modules, such as Figure 3 and Figure 4 As shown, including:

[0086] Data collection module: obtain basic data;

[0087] The basic data include both the material properties and combustion characteristics of the photovoltaic modules and the environmental parameters; among which:

[0088] The material properties mainly include thermal conductivity, density and specific heat capacity;

[0089] The combustion characteristics mainly include combustion heat and initial temperature;

[0090] The environmental parameters mainly include wind speed, ambient temperature and humidity;

[0091] Data analysis module: analyzes fire spread parameters through the basic data; specifically includes:

[0092] Model building unit: building a thermal diffusivity calculation model;

[0093]

[0094] Where: T is the temperature of the photovoltaic module (K), t is the time (s), α is the thermal diffusivity (m 2 / s), λ is the thermal conductivity (W / m·K), ρ is the density of the photovoltaic module (kg / m 3 ), c p is the specific heat capacity of the photovoltaic module (J / kg·K), is the Laplace operator.

[0095] Speed ​​analysis unit: calculates the flame spread speed based on the thermal diffusivity calculation model;

[0096] Flame spread speed calculation formula:

[0097]

[0098] Where: S f is the flame spread speed (m / s), ΔH is the combustion heat of the PV module (J / kg), and T0 is the initial temperature (K).

[0099] Speed ​​correction unit: Use environmental parameters to correct the flame spread speed;

[0100] The correction formula is:

[0101] S corr =S f ×f(v,T a , H)

[0102] f(v,T a , H)=1+a v v+a T (T a -T0)-a H H

[0103] S corr is the corrected flame spread speed (m / s), v is the wind speed (m / s), T a is the ambient temperature (K), H is the humidity (%). f is the correction function, a v is the wind speed coefficient (value is 0.1), aT is the temperature coefficient (value is 0.05), a H is the humidity coefficient (the value is 0.02).

[0104] Distance analysis unit: Calculates the fire spread distance based on the corrected flame spread speed;

[0105] The fire spread distance formula is:

[0106]

[0107] Where D is the flame spread distance (m) and t is the time (s).

[0108] Specific implementation cases:

[0109] A photovoltaic power station is located in a tropical area, and the photovoltaic modules are made of monocrystalline silicon. The local climate characteristics include high temperature, high humidity and strong wind. When conducting a fire risk assessment, it is necessary to calculate the speed and distance of the fire spread of the photovoltaic modules in order to formulate corresponding fire prevention measures.

[0110] First, collect the following basic data:

[0111] Material properties of photovoltaic modules

[0112] Thermal conductivity (λ): 130W / m·K

[0113] Photovoltaic module density (ρ): 2330kg / m 3

[0114] Specific heat capacity of photovoltaic modules (c p ); 700 J / kg·K

[0115] Combustion characteristic parameters

[0116] Photovoltaic module combustion heat ΔH: 25000J / kg

[0117] Initial temperature T0: 3000K

[0118] Environmental parameters

[0119] Wind speed v: 5m / s

[0120] Ambient temperature Ta: 310K

[0121] Humidity H: 60%

[0122] The basic data is then used to analyze the fire spread parameters:

[0123] Heat conduction calculation

[0124] The finite difference method or finite element method is used to solve the heat conduction equation and obtain the temperature field distribution.

[0125]

[0126] Flame spread rate calculation

[0127] The flame spread speed is calculated based on the thermal diffusivity calculation model. The flame spread speed calculation formula is:

[0128]

[0129] Environmental Modification

[0130] Correction of flame spread rate using correction formula

[0131] f(v,T a , H)=1+0.1v+0.05(T a -300)-0.02H

[0132] S corr =S f ×(1+0.1×5+0.05×10-0.02×60)=1.2m / s

[0133] Fire spread distance calculation

[0134] Assuming the fire spread time is 10 minutes (600 seconds), the fire spread distance is:

[0135]

[0136] Result Output

[0137] Through the above calculations, it was found that the fire spread speed of the photovoltaic modules of the photovoltaic power station was 1.2m / s, and the fire spread distance was 720 meters within 10 minutes.

[0138] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above-mentioned method for analyzing fire spread parameters of photovoltaic modules.

[0139] A computer program product comprises a computer program, which implements the above-mentioned method for analyzing fire spread parameters of photovoltaic modules when executed by a processor.

[0140] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When the use is implemented in whole or in part in the form of a computer program product, the computer program product includes one or more computer instructions. When the computer program instructions are loaded or executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL) or wireless (e.g., infrared, wireless, microwave, etc.) mode) to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state hard disk SolidState Disk (SSD)), etc.

[0141] The above is only a preferred embodiment of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for analyzing fire spread parameters of photovoltaic modules, characterized in that: include: S1. Obtain basic data; the basic data includes environmental parameters, material properties and combustion characteristics of photovoltaic modules; the material properties include thermal conductivity, density and specific heat capacity; the combustion characteristics include combustion heat and initial temperature; the environmental parameters include wind speed, ambient temperature and humidity; S2. Analyze the fire spread parameters based on the basic data; specifically include: S201, constructing a thermal diffusivity calculation model; S202, calculating the flame spread speed based on the thermal diffusivity calculation model; Flame spread speed calculation formula: ； in: is the flame spread speed, To burn heat for photovoltaic panels, is the initial temperature, is the thermal diffusivity, is the specific heat capacity of the photovoltaic module; S203. Correct the flame spread speed using environmental parameters; the correction formula is: ； is the corrected flame spread speed, v is the wind speed, T a is the ambient temperature, H is the humidity, f is the correction function, a v is the wind speed coefficient, a T is the temperature coefficient, a H is the humidity coefficient; S204. Calculate the fire spread distance based on the corrected flame spread speed.

2. The method for analyzing fire spread parameters of photovoltaic modules according to claim 1, characterized in that: In S201, the expression of the thermal diffusivity calculation model is: ； Where: T is the temperature of the photovoltaic module, t is the time, is the thermal diffusivity, is the thermal conductivity, is the density of photovoltaic modules, is the specific heat capacity of the photovoltaic module, is the Laplace operator.

3. The method for analyzing fire spread parameters of photovoltaic modules according to claim 2, characterized in that: In S204, the calculation formula for fire spread distance is: , D is the flame spread distance.

4. A device for analyzing fire spread parameters of photovoltaic modules, characterized in that: include: Data collection module: obtaining basic data; the basic data includes environmental parameters, material properties of photovoltaic modules and combustion characteristics; the material properties include thermal conductivity, density and specific heat capacity; the combustion characteristics include combustion heat and initial temperature; the environmental parameters include wind speed, ambient temperature and humidity; Data analysis module: analyzes fire spread parameters through the basic data; specifically includes: Model building unit: building a thermal diffusivity calculation model; Speed ​​analysis unit: calculates the flame spread speed based on the thermal diffusivity calculation model; Speed ​​correction unit: Use environmental parameters to correct the flame spread speed; Distance analysis unit: calculates the fire spread distance based on the corrected flame spread speed; Flame spread speed calculation formula: ； in: is the flame spread speed, To burn heat for photovoltaic panels, is the initial temperature, is the thermal diffusivity, is the specific heat capacity of the photovoltaic module; The correction formula for flame spread speed is: ； is the corrected flame spread speed, v is the wind speed, T a is the ambient temperature, H is the humidity, f is the correction function, a v is the wind speed coefficient, a T is the temperature coefficient, a H is the humidity coefficient.

5. The photovoltaic module fire spread parameter analysis device according to claim 4, characterized in that: The expression of the thermal diffusivity calculation model is: ； Where: T is the temperature of the photovoltaic module, t is the time, is the thermal diffusivity, is the thermal conductivity, is the density of photovoltaic modules, is the specific heat capacity of the photovoltaic module, is the Laplace operator; The calculation formula for fire spread distance is: , D is the flame spread distance.

6. A computer-readable storage medium storing a computer program, wherein the program, when executed by a processor, implements the method for analyzing fire spread parameters of a photovoltaic module according to any one of claims 1 to 3.

7. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method for analyzing the fire spread parameters of a photovoltaic module as claimed in any one of claims 1 to 3 is implemented.

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