Photovoltaic short circuit and shadow fault identification method and system

Abstract

The present invention discloses a photovoltaic short circuit and shadow fault identification method and system, which relates to the field of photovoltaic array fault diagnosis. The method includes: obtaining a D-group current-voltage curve of a photovoltaic array; obtaining a downhill inflection point in the D-group current-voltage curve, and determining whether the photovoltaic array is in a fault state according to the number of downhill inflection points in the D-group current-voltage curve; when the photovoltaic array is in a fault state, obtaining the downhill inflection point coordinate point at the downhill inflection point in the current-voltage curve, and calculating the inflection point voltage distance according to the inflection point voltage of the downhill inflection point coordinate point; calculating the curve curvature according to the downhill inflection point coordinate point and the inflection point voltage distance, and determining the fault type as a short circuit fault or a shadow fault according to the relationship between the curve curvature and a preset threshold value. Compared with the prior art, the present invention does not require a large amount of computing resources and storage resources, has high recognition accuracy, and has low hardware computing power requirements, and is particularly suitable for distribution network areas with limited computing power resources.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic array fault diagnosis, and more specifically, to a photovoltaic short circuit and shadow fault identification method and system. Background Art

[0002] With the intensification of the global energy crisis and the increasing severity of environmental pollution, photovoltaic power generation, as a clean and renewable energy source, has received widespread attention and application. However, various faults may occur in the equipment of photovoltaic power generation system during operation, such as component aging, shading, short circuit, etc. These faults will affect the normal operation and power generation efficiency of photovoltaic power generation system. Therefore, it is of great significance to timely and accurately identify and handle the faults of photovoltaic power generation system.

[0003] At present, photovoltaic fault identification mainly relies on manual inspection and regular maintenance. This method is not only labor-intensive, but also has certain risks of misjudgment and missed judgment. In order to improve the accuracy and efficiency of photovoltaic fault identification, researchers have proposed some data-driven fault identification methods, such as expert system-based fault diagnosis and machine learning-based fault identification. However, these methods often require a large amount of training data and complex algorithms, need to be implemented based on a large amount of computing resources and storage resources, and have limited effects on different types of fault identification. Summary of the invention

[0004] In order to overcome the problems of the prior art described above, which require a large amount of computing resources and storage resources and have limited fault identification effect, the present invention provides a photovoltaic short circuit and shadow fault identification method and system.

[0005] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0006] In a first aspect, a photovoltaic short circuit and shadow fault identification method includes:

[0007] Obtain the D-group current-voltage curve of the photovoltaic array;

[0008] Obtaining downhill inflection points in the current-voltage curve of group D, and determining whether the photovoltaic array is in a fault state according to the number of downhill inflection points in the current-voltage curve of group D;

[0009] When the photovoltaic array is in a fault state, obtaining a downhill inflection point coordinate point at a downhill inflection point in the current-voltage curve, and calculating an inflection point voltage distance according to an inflection point voltage at the downhill inflection point coordinate point;

[0010] The curvature of the curve is calculated based on the downhill inflection point coordinate point and the inflection point voltage distance, and the fault type is determined based on the relationship between the curvature of the curve and a preset threshold value; the fault type is a short circuit fault or a shadow fault.

[0011] In a second aspect, a photovoltaic short circuit and shadow fault identification system is provided, applying the method described in the first aspect, comprising:

[0012] A curve acquisition module, used to acquire a current-voltage curve of group D of the photovoltaic array; and also used to acquire a downslope inflection point in the current-voltage curve of group D;

[0013] A fault state judgment module, used to determine whether the photovoltaic array is in a fault state according to the number of downhill inflection points in the current-voltage curve of group D; and also used to make the fault type identification module enter a working state when the photovoltaic array is in a fault state;

[0014] A fault type identification module is used to obtain the downhill inflection point coordinate point at the downhill inflection point in the current-voltage curve when the photovoltaic array is in a fault state, and calculate the inflection point voltage distance based on the inflection point voltage of the downhill inflection point coordinate point; it is also used to calculate the curve curvature based on the downhill inflection point coordinate point and the inflection point voltage distance, and determine the fault type based on the relationship between the curve curvature and a preset threshold value; the fault type is a short circuit fault or a shadow fault.

[0015] According to a third aspect, an electronic device includes:

[0016] A memory for storing computer executable instructions or computer programs;

[0017] The processor is used to implement the method described in the first aspect when executing the computer executable instructions or computer program stored in the memory.

[0018] In a fourth aspect, a computer-readable storage medium stores at least one instruction, at least one program, a code set or an instruction set, wherein the at least one instruction, at least one program, a code set or an instruction set is loaded and executed by a processor to implement the method described in the first aspect.

[0019] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0020] The present invention proposes a photovoltaic short circuit and shadow fault identification method. For photovoltaic arrays, by obtaining the downhill inflection points in the photovoltaic array current-voltage curve, judging whether the photovoltaic array is in a fault state according to the number of downhill inflection points, and calculating the curvature of the curve according to the downhill inflection points, the fault type is determined. Compared with traditional manual inspections, the present invention has high fault identification accuracy, low risk of misjudgment and missed judgment, can quickly and accurately identify photovoltaic array short circuit and shadow faults, and has low time cost; compared with artificial intelligence methods, the present invention does not require a large amount of computing resources and storage resources, has low requirements on hardware computing power, and has strong engineering practicality, and is particularly suitable for distribution network areas with limited computing power resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a flow chart of the photovoltaic short circuit and shadow fault identification method in Example 1 of the present application;

[0022] Figure 2 This is another schematic flow chart of the photovoltaic short circuit and shadow fault identification method in Example 1 of the present application;

[0023] Figure 3 This is an example diagram of the current-voltage curve during a short circuit fault in Example 2 of the present application;

[0024] Figure 4 This is an example diagram of the current-voltage curve during a shadow fault in Example 2 of the present application;

[0025] Figure 5 This is a structural schematic diagram of the photovoltaic short circuit and shadow fault identification system in Example 3 of the present application. DETAILED DESCRIPTION

[0026] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and need not be used to describe a specific order or sequential order. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, which is only to describe the distinction mode adopted by the objects of the same attributes when describing in the embodiments of the present application. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, so that the process, method, system, product or equipment comprising a series of units need not be limited to those units, but may include other units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0027] The drawings are for illustrative purposes only and should not be construed as limiting the present patent;

[0028] In order to better illustrate the present embodiment, some parts in the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product;

[0029] It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0030] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0031] Example 1

[0032] This embodiment provides a photovoltaic short circuit and shadow fault identification method, referring to FIG1, comprising:

[0033] Obtain the D-group current-voltage curve of the photovoltaic array;

[0034] Obtaining downhill inflection points in the current-voltage curve of group D, and determining whether the photovoltaic array is in a fault state according to the number of downhill inflection points in the current-voltage curve of group D;

[0035] When the photovoltaic array is in a fault state, obtaining a downhill inflection point coordinate point at a downhill inflection point in the current-voltage curve, and calculating an inflection point voltage distance according to an inflection point voltage at the downhill inflection point coordinate point;

[0036] The curvature of the curve is calculated based on the downhill inflection point coordinate point and the inflection point voltage distance, and the fault type is determined based on the relationship between the curvature of the curve and a preset threshold value; the fault type is a short circuit fault or a shadow fault.

[0037] The above embodiment obtains the downhill inflection points in the photovoltaic array current-voltage curve, determines whether the photovoltaic array is in a fault state according to the number of downhill inflection points, and calculates the curvature of the curve according to the downhill inflection points to determine the fault type. Compared with the existing technology, its computing cost and storage cost are low, and the recognition accuracy is high, which is particularly suitable for distribution network areas with limited computing resources.

[0038] In some preferred embodiments, referring to FIG. 2 , when the photovoltaic array is in a fault state, the downhill inflection point coordinate points in any group of the current-voltage curves include a first downhill inflection point coordinate point and a second downhill inflection point coordinate point; the curvature of the curve is calculated based on the downhill inflection point coordinate points and the inflection point voltage distance, including:

[0039] For The current-voltage curve of the group , according to the inflection point voltage of the first downslope inflection point coordinate point The distance from the knee voltage The voltage value is found on the current-voltage curve. The coordinate point of is recorded as the marked coordinate point; among them, ;

[0040] Connect the marked coordinate point with the second downhill turning point coordinate point to obtain a connecting line, and record the length of the connecting line , and establish a perpendicular line between it and the current-voltage curve on the connecting line;

[0041] Traverse all vertical lines and record the maximum vertical line distance , according to the maximum perpendicular distance And the length of the connection , the curvature of the curve is calculated .

[0042] In some optional embodiments, the connection length is obtained by the following formula:

[0043]

[0044] In the formula, , , , Respectively represent the inflection point voltage corresponding to the first downslope inflection point coordinate point in the current-voltage curves of groups 1, 2, ..., and D; , , , Respectively represent the currents corresponding to the marked coordinate points in the current-voltage curves of groups 1, 2, ..., and D; represent the inflection point voltages corresponding to the coordinate points of the second downslope inflection points in the current-voltage curves of groups 1, 2, ..., and D, respectively, , , , Indicates the inflection point current corresponding to the coordinate point of the second downslope inflection point; Respectively represent the inflection point voltage distances in the current-voltage curves of the 1st, 2nd, ..., and D groups.

[0045] In some optional embodiments, the curvature of the curve is obtained by the following formula:

[0046]

[0047] In the formula, Respectively represent the curvature of the current-voltage curves of the 1st, 2nd, ..., and D groups; Respectively represent the maximum vertical distances of the current-voltage curves of groups 1, 2, ..., and D; Respectively represent the connection lengths in the current-voltage curves of groups 1, 2, ..., and D.

[0048] In some examples, the current-voltage curve of group D of the photovoltaic array is obtained. , ,…, ; Wherein, D is an integer greater than 2, the The ranges are , , , …, , is the open circuit voltage of the photovoltaic array;

[0049] Assuming that the PV array is in a fault state, obtain the voltage value corresponding to the first downslope inflection point of the current-voltage curve of group D , , , and the voltage value of the second downslope inflection point , respectively calculate the inflection point voltage distance ;in, ;

[0050] Extract the current-voltage curve of photovoltaic array group D Respectively The voltage and current corresponding coordinates ;

[0051] Extract the current-voltage curve of photovoltaic array group D The voltage and current corresponding coordinates at the corresponding second downslope inflection point are ;

[0052] Connecting coordinate points and , and ,……, and , get the connection ;

[0053] Get the maximum vertical distance between each connection line and the corresponding current-voltage curve , respectively calculate the corresponding curve curvature .

[0054] In some preferred embodiments, referring to FIG. 2 , the step of determining whether the photovoltaic array is in a fault state according to the number of downhill inflection points in the current-voltage curve of group D includes:

[0055] When the current-voltage curve of group D When there is only one downhill inflection point, the photovoltaic array is considered to be in a non-fault state; otherwise, the photovoltaic array is considered to be in a fault state.

[0056] In some preferred embodiments, referring to FIG. 2 , the determining of the fault type according to the relationship between the curvature of the curve and the preset threshold value includes:

[0057] When the curvature of the curves of all the current-voltage curves is greater than or equal to the preset threshold value, it is considered that a short circuit fault occurs in the photovoltaic array;

[0058] When the curvature of at least one set of the current-voltage curves is less than the preset threshold value, and the curvatures of the remaining current-voltage curves are greater than or equal to the preset threshold value, it is considered that a shadow fault occurs in the photovoltaic array.

[0059] In some preferred embodiments, obtaining the downslope inflection point in the current-voltage curve includes:

[0060] For The current-voltage curve of the group is:

[0061] conduct Synchronous sampling at each moment to obtain the timing data of the voltage And the corresponding timing data about current , recorded as a time series data pair ( );in, ;in, , , represents the open circuit voltage of the photovoltaic array;

[0062] Traverse the time series data pairs of the second group to the The time series data pairs are grouped to obtain time series data pairs that satisfy the following formula:

[0063]

[0064] The corresponding coordinate points of all time series data pairs that satisfy the above formula are recorded as the downhill turning points.

[0065] Example 2

[0066] This embodiment conducts a simulation experiment on the method provided in Embodiment 1.

[0067] In this simulation experiment, two groups of short circuit faults and two groups of shadow fault simulation scenarios were set, where the shadow fault was simulated by reducing the original light intensity. The standard light intensity set in the experiment is , the ambient temperature is 25℃, the short circuit fault is simulated under the standard parameter setting, and the illumination intensity of the two groups of shadow fault simulation is , The simulation is performed under the following settings, and 7 different scenarios are shown in the following table:

[0068] Table 1 Simulation scenario settings

[0069] Scenario Light intensity temperature Branch settings Ⅰ 1000 W / m2 25 No short circuit fault Ⅱ 600 W / m2 25 No short circuit fault Ⅲ 1000 W / m2 25 A component is short-circuited Ⅳ 1000 W / m2 25 Two components short circuit Ⅴ One branch 600 W / m2 25 No short circuit fault Ⅵ One branch 200 W / m2, the other branch 400 W / m2 25 No short circuit fault Ⅶ One branch 200 W / m2, the other two branches 400 W / m2 25 No short circuit fault

[0070] Figures 3 and 4 show the first set of current-voltage curves for short circuit fault and shadow fault, respectively. ; Open circuit voltage ; Among them, the horizontal axis represents voltage and the vertical axis represents current.

[0071] The curvature of the curve for short-circuit fault scenario III is calculated as follows: , the shadow failure scenario V is It can be seen that there is a big difference in the curvature of the curves under short-circuit fault and shadow fault. This indicator can be used to effectively identify whether the photovoltaic array has a shadow fault or a short-circuit fault.

[0072] Example 3

[0073] This embodiment provides a photovoltaic short circuit and shadow fault identification system. Referring to FIG. 5 , the method in the application embodiment 1 includes:

[0074] A curve acquisition module, used to acquire a current-voltage curve of group D of the photovoltaic array; and also used to acquire a downslope inflection point in the current-voltage curve of group D;

[0075] A fault state judgment module, used to determine whether the photovoltaic array is in a fault state according to the number of downhill inflection points in the current-voltage curve of group D; and also used to make the fault type identification module enter a working state when the photovoltaic array is in a fault state;

[0076] A fault type identification module is used to obtain the downhill inflection point coordinate point at the downhill inflection point in the current-voltage curve when the photovoltaic array is in a fault state, and calculate the inflection point voltage distance based on the inflection point voltage of the downhill inflection point coordinate point; it is also used to calculate the curve curvature based on the downhill inflection point coordinate point and the inflection point voltage distance, and determine the fault type based on the relationship between the curve curvature and a preset threshold value; the fault type is a short circuit fault or a shadow fault.

[0077] It can be understood that the system / device of this embodiment corresponds to the method of the above-mentioned embodiment 1, and the options in the above-mentioned embodiment 1 are also applicable to this embodiment, so they are not described repeatedly here.

[0078] Example 4

[0079] This embodiment provides a computer-readable storage medium, on which is stored at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by a processor, so that the processor executes part or all of the steps of the method provided in Example 1 of the present application.

[0080] It is understood that the storage medium may be transient or non-transient. Exemplarily, the storage medium includes, but is not limited to, a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0081] Exemplarily, the processor may be a central processing unit (CPU), a microprocessor (MPU), a digital signal processor (DSP), or a field programmable gate array (FPGA).

[0082] In some examples, a computer program product is provided, which can be implemented in hardware, software or a combination thereof. As a non-limiting example, the computer program product can be embodied as the storage medium, or as a software product, such as an SDK (Software Development Kit).

[0083] As a non-limiting example, a computer program product is provided, the computer program product includes a computer program or a computer executable instruction, the computer program or the computer executable instruction is stored in a computer-readable storage medium. A processor of an electronic device reads the computer program or the computer executable instruction from the computer-readable storage medium, and the processor executes the computer executable instruction, so that the electronic device performs some or all steps of the method described in the embodiment of the present application.

[0084] In some examples, a computer program is provided, comprising a computer-readable code, and when the computer-readable code is run in a computer device, a processor in the computer device executes a part or all of the steps in the method.

[0085] This embodiment also proposes an electronic device, including a memory and a processor, wherein the memory stores at least one instruction, at least one program, a code set or an instruction set, and when the processor executes the at least one instruction, at least one program, a code set or an instruction set, it implements part or all of the steps of the method described in Example 1.

[0086] In some examples, a hardware entity of the electronic device is provided, including: a processor, a memory and a communication interface; wherein the processor generally controls the overall operation of the electronic device; the communication interface is used to enable the electronic device to communicate with other terminals or servers through a network; the memory is configured to store instructions and applications executable by the processor, and can also cache data to be processed or processed by the processor and various modules in the electronic device (including but not limited to image data, audio data, voice communication data and video communication data), which can be implemented through flash memory (FLASH) or random access memory (RAM).

[0087] Furthermore, data may be transmitted between the processor, the communication interface and the memory via a bus, which may include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors and memories together.

[0088] It can be understood that the options in the above-mentioned embodiment 1 are also applicable to this embodiment, so they will not be described again here.

[0089] The same or similar reference numerals correspond to the same or similar components;

[0090] The terms used to describe the positional relationship in the drawings are only used for illustrative purposes and should not be construed as limiting the present application;

[0091] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0092] Obviously, the above-mentioned embodiments of the present application are merely examples for clearly illustrating the present application, and are not intended to limit the implementation methods of the present application, and are not intended to limit the present application. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above descriptions. Each functional module or unit can be integrated together to form an independent part, or each module can exist separately, or two or more modules can be integrated to form an independent part. It is not necessary and impossible to enumerate all the implementation methods here. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the claims of the present application.

Claims

1. A photovoltaic short circuit and shadow fault identification method, characterized in that: include: Obtain the D-group current-voltage curve of the photovoltaic array; Obtaining downhill inflection points in the current-voltage curve of group D, and determining whether the photovoltaic array is in a fault state according to the number of downhill inflection points in the current-voltage curve of group D; When the photovoltaic array is in a fault state, a downhill inflection point coordinate point at the downhill inflection point in the current-voltage curve is obtained, and the inflection point voltage distance is calculated according to the inflection point voltage of the downhill inflection point coordinate point; wherein, when the photovoltaic array is in a fault state, any group of the downhill inflection point coordinate points in the current-voltage curve includes a first downhill inflection point coordinate point and a second downhill inflection point coordinate point; The curvature of the curve is calculated according to the downhill inflection point coordinate point and the inflection point voltage distance, and the fault type is determined according to the relationship between the curvature of the curve and the preset threshold value; the fault type is a short circuit fault or a shadow fault; wherein the curvature of the curve is calculated according to the downhill inflection point coordinate point and the inflection point voltage distance, including: For the jth group of current-voltage curves I j =f(V j ), according to the inflection point voltage of the first downslope inflection point coordinate point The distance ΔV from the knee voltage j The voltage value is found on the current-voltage curve. The coordinate point is recorded as the marked coordinate point; where j = 1, 2, ..., D; Connect the marked coordinate point and the second downhill turning point coordinate point to obtain a connecting line, and record the length of the connecting line l j , and establish a perpendicular line between it and the current-voltage curve on the connecting line; Traverse all vertical lines and record the maximum vertical line distance According to the maximum vertical distance And the connection length l j , calculate the curvature k of the curve j .

2. A photovoltaic short circuit and shadow fault identification method according to claim 1, characterized in that: The connection length is obtained by the following formula: In the formula, I respectively represent the inflection point voltage corresponding to the first downslope inflection point coordinate point in the current-voltage curves of the 1st, 2nd, ..., Dth groups; 1，f ,I 2，f ,…,I D，f Respectively represent the currents corresponding to the marked coordinate points in the current-voltage curves of groups 1, 2, ..., and D; I respectively represent the inflection point voltage corresponding to the coordinate point of the second downslope inflection point in the current-voltage curve of the first, second, ..., and D groups, I 1，t ,I 2，t ,…,I D，t represents the inflection point current corresponding to the coordinate point of the second downslope inflection point; ΔV1, ΔV2, ..., ΔV D Respectively represent the inflection point voltage distances in the current-voltage curves of the 1st, 2nd, ..., and D groups.

3. A photovoltaic short circuit and shadow fault identification method according to claim 1, characterized in that: The curvature of the curve is obtained by the following formula: In the formula, k1, k2, …, k D Respectively represent the curvature of the current-voltage curves of the 1st, 2nd, ..., and D groups; Respectively represent the maximum vertical distances of the current-voltage curves of the 1st, 2nd, ..., Dth groups; l1, l2, ..., l D Respectively represent the connection lengths in the current-voltage curves of groups 1, 2, ..., and D.

4. A photovoltaic short circuit and shadow fault identification method according to claim 1, characterized in that: The determining whether the photovoltaic array is in a fault state according to the number of downhill inflection points in the current-voltage curve of group D includes: When the current-voltage curve of group D is I1=f(V1), I2=f(V2),…,I D =f(V D ) have only one downhill inflection point, the photovoltaic array is deemed not to be in a fault state; otherwise, the photovoltaic array is deemed to be in a fault state.

5. A photovoltaic short circuit and shadow fault identification method according to claim 1, characterized in that: Determining the fault type according to the relationship between the curvature of the curve and the preset threshold value includes: When the curvature of the curves of all the current-voltage curves is greater than or equal to the preset threshold value, it is considered that a short circuit fault occurs in the photovoltaic array; When the curvature of at least one set of the current-voltage curves is less than the preset threshold value, and the curvatures of the remaining current-voltage curves are greater than or equal to the preset threshold value, it is considered that a shadow fault occurs in the photovoltaic array.

6. A photovoltaic short circuit and shadow fault identification method according to claim 1, characterized in that: Acquiring the downslope inflection point in the current-voltage curve includes: For the current-voltage curve of group j: Perform synchronous sampling at N moments to obtain the timing data V about the voltage (1) ,V (2) ,…,V (N) And the corresponding time series data about the current I (1) ,I (3) ,…,I (N) , recorded as a time series data pair (V (i) ,I (i) ), where j = 1, 2, ..., D, where V (1) <V (2) <… <V (N) , V (N) =V oc , V oc represents the open circuit voltage of the photovoltaic array; Traverse the time series data pairs from the second group to the N-1th group to obtain the time series data pairs that satisfy the following formula: ((V (i) ·I (i) )-((V (i-1) ·I (i-1) )))((V (i+1) ·I (i+1) )-((V (i) ·I (i) )))<0 The corresponding coordinate points of all time series data pairs that satisfy the above formula are recorded as the downhill turning points.

7. A photovoltaic short circuit and shadow fault identification system, applying the method according to any one of claims 1 to 6, characterized in that: include: A curve acquisition module, used to acquire a current-voltage curve of group D of the photovoltaic array; and also used to acquire a downslope inflection point in the current-voltage curve of group D; A fault state judgment module, used to determine whether the photovoltaic array is in a fault state according to the number of downhill inflection points in the current-voltage curve of group D; It is also used to make the fault type identification module enter the working state when the photovoltaic array is in a fault state; wherein, when the photovoltaic array is in a fault state, the downhill inflection point coordinate points in any group of the current-voltage curves include a first downhill inflection point coordinate point and a second downhill inflection point coordinate point; A fault type identification module is used for obtaining the downhill inflection point coordinate point at the downhill inflection point in the current-voltage curve when the photovoltaic array is in a fault state, and calculating the inflection point voltage distance according to the inflection point voltage of the downhill inflection point coordinate point; and is also used for calculating the curve curvature according to the downhill inflection point coordinate point and the inflection point voltage distance, and determining the fault type according to the relationship between the curve curvature and a preset threshold value; the fault type is a short circuit fault or a shadow fault; wherein, the curve curvature is calculated according to the downhill inflection point coordinate point and the inflection point voltage distance, including: For the jth group of current-voltage curves I j =f(V j ), according to the inflection point voltage of the first downslope inflection point coordinate point The distance ΔV from the knee voltage j The voltage value is found on the current-voltage curve. The coordinate point is recorded as the marked coordinate point; where j = 1, 2, ..., D; Connect the marked coordinate point and the second downhill turning point coordinate point to obtain a connecting line, and record the length of the connecting line l j , and establish a perpendicular line between it and the current-voltage curve on the connecting line; Traverse all vertical lines and record the maximum vertical line distance According to the maximum vertical distance And the connection length l j , calculate the curvature k of the curve j .

8. An electronic device, characterized in that: include: A memory for storing computer executable instructions or computer programs; The processor is used to implement the method according to any one of claims 1 to 6 when executing the computer executable instructions or computer program stored in the memory.

9. A computer-readable storage medium, characterized in that: The storage medium stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, at least one program, a code set or an instruction set is loaded and executed by a processor to implement the method as described in any one of claims 1-6.

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