Photovoltaic array fault detection method and apparatus, and computer device and storage medium

Abstract

The present application relates to the technical field of photovoltaic array fault detection. Disclosed are a photovoltaic array fault detection method and apparatus, and a computer device and a storage medium. The method comprises: acquiring a photovoltaic array state information base; using a signal transmission system to send a step signal to a photovoltaic array, and acquiring a state reflection signal of a photovoltaic module; and sending the state reflection signal to a filtering system for filtering to obtain a target state reflection signal waveform diagram, and performing fault detection on the photovoltaic array on the basis of the photovoltaic array state information base to obtain a fault detection result of the photovoltaic array. In the present application, a state reflection signal of each photovoltaic module in each state in a photovoltaic array is matched with a photovoltaic array state information base, so as to determine a fault state of each photovoltaic module in the photovoltaic array and obtain a fault detection result of the photovoltaic array, thereby realizing all-weather intelligent fault detection of the photovoltaic array, improving the fault detection efficiency and reducing fault detection costs.

Description

Photovoltaic array fault detection method, device, computer equipment and storage medium Technical Field

[0001] The present application relates to the technical field of photovoltaic array fault detection, and in particular to a photovoltaic array fault detection method, apparatus, computer equipment, and storage medium. Background Art

[0002] With the continuous improvement of living standards, photovoltaic power generation has become an important source of electricity for people's daily lives. Photovoltaic arrays are often installed in places with relatively harsh natural environments, such as deserts and wastelands. Therefore, the photovoltaic components and lines inside them are often exposed to solar radiation, rain, fog, rain and other extreme weather conditions, as well as line aging and wear. These problems reduce the reliability and safety of photovoltaic power generation systems. In addition, most of them are located in relatively remote areas with harsh environments, making maintenance difficult and costly.

[0003] Traditional photovoltaic array fault detection methods usually use output current and voltage signals to detect whether there are faults such as line breaks in photovoltaic modules within the photovoltaic array. However, this method may cause misdetection due to aging problems in the photovoltaic array lines, and the efficiency of this method is relatively low.

[0004] Summary of the Invention

[0005] In view of this, the present application provides a photovoltaic array fault detection method, apparatus, computer equipment and storage medium to solve the problems of low detection accuracy and detection efficiency of traditional photovoltaic array fault detection methods.

[0006] In a first aspect, the present application provides a photovoltaic array fault detection method, wherein the photovoltaic array includes at least one photovoltaic component, and the photovoltaic array is respectively connected to a signal transmission system and a filtering system, the signal transmission system includes a first signal transmission device connected to one end of the photovoltaic array, and a second signal transmission device connected to the other end of the photovoltaic array; the method includes: obtaining a photovoltaic array status information library; using the first signal transmission device and the second signal transmission device in the signal transmission system to send step signals to the photovoltaic array respectively; obtaining a status reflection signal of each photovoltaic component in the photovoltaic array based on the step signal; sending the status reflection signal of each photovoltaic component to the filtering system for filtering processing to obtain a target status reflection signal waveform diagram of each photovoltaic component; performing fault detection on the photovoltaic array based on the photovoltaic array status information library and the target status reflection signal waveform diagram of each photovoltaic component to obtain a fault detection result of the photovoltaic array.

[0007] The photovoltaic array fault detection method provided in the present application matches the state reflection signal of each photovoltaic component in the photovoltaic array in each state with the photovoltaic array state information library, thereby judging the fault state of each photovoltaic component in the photovoltaic array and obtaining the fault detection result of the photovoltaic array, thereby realizing all-weather intelligent fault detection of the photovoltaic array, improving the efficiency of fault detection, and reducing the cost of fault detection.

[0008] In an optional embodiment, obtaining a photovoltaic array state information library includes: using a signal transmission system to send a step signal to the photovoltaic array, and obtaining at least one state reflection signal of each photovoltaic component in the photovoltaic array based on the step signal; sending each state reflection signal of each photovoltaic component to a filtering system for filtering processing to obtain at least one state reflection signal waveform of each photovoltaic component; and establishing a photovoltaic array state information library based on each state reflection signal waveform of each photovoltaic component.

[0009] This application establishes a photovoltaic array status information library based on the state reflection signal waveform diagram of each photovoltaic component in the photovoltaic array under various states, which provides a detection basis for subsequent photovoltaic array fault detection. Further, it can improve the efficiency of fault detection and reduce the cost of fault detection.

[0010] In an optional embodiment, after using the signal transmission system to send a step signal to the photovoltaic array, and before obtaining the status reflection signal of each photovoltaic component in the photovoltaic array based on the step signal, the method also includes: when the first signal transmission device does not receive the status reflection signal within a preset unit time, sending a step signal to send a request instruction to the second signal transmission device; judging whether the first signal transmission device has received a response instruction sent by the second signal transmission device; when the first signal transmission device does not receive the response instruction, determining that the second signal transmission device has failed; when the first signal transmission device receives the response instruction and the first signal transmission device does not receive the status reflection signal within the preset unit time, determining that the second signal transmission device has failed.

[0011] The present application realizes fault detection of the signal transmission devices at the left and right ends of the photovoltaic array through the status of the reflected signals received by the signal transmission devices at the left and right ends of the photovoltaic array.

[0012] In an optional embodiment, the filtering system includes a first high-pass filter and a second high-pass filter; sending the state reflection signal of each photovoltaic component to the filtering system for filtering processing to obtain a target state reflection signal waveform of each photovoltaic component, including: sending the state reflection signal of each photovoltaic component to the first high-pass filter for filtering to obtain a first state reflection signal waveform and a first signal-to-noise ratio value; sending the state reflection signal of each photovoltaic component after filtering by the first high-pass filter to the second high-pass filter for filtering to obtain a second state reflection signal waveform and a second signal-to-noise ratio value; comparing the first signal-to-noise ratio value with a preset signal-to-noise ratio threshold, and comparing the second state reflection signal waveform to a preset signal-to-noise ratio threshold. The waveform diagram of the target state reflection signal is compared with the waveform diagram of the first state reflection signal to obtain a difference value; when the first signal-to-noise ratio value is less than a preset signal-to-noise ratio threshold, and the difference value is less than the preset difference threshold, the signal cutoff frequencies of the first high-pass filter and the second high-pass filter are adjusted respectively, and based on the adjusted first high-pass filter and the second high-pass filter, the state reflection signal of each photovoltaic component is processed until the second signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, the adjustment is stopped, and the target state reflection signal waveform diagram is obtained; when the first signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, and the difference value is less than the preset difference threshold, the second state reflection signal waveform diagram is used as the target state reflection signal waveform diagram.

[0013] The present application improves the efficiency and quality of filtering the state reflection signal by adjusting the signal cutoff frequencies of the first high-pass filter and the second high-pass filter in the filtering system.

[0014] In an optional embodiment, after comparing the second-state reflection signal waveform with the first-state reflection signal waveform to obtain a difference value, the method further includes: when the first signal-to-noise ratio value is less than a preset signal-to-noise ratio threshold and the difference value is greater than or equal to the preset difference threshold, determining that the first high-pass filter and the second high-pass filter have failed; when the first signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold and the difference value is greater than the preset difference threshold, determining that the first high-pass filter and the second high-pass filter have failed.

[0015] The present application realizes fault detection of the first high-pass filter and the second high-pass filter by comparing the filtering results of the first high-pass filter and the second high-pass filter on the state reflection signal.

[0016] In an optional embodiment, a photovoltaic array state information library is established based on each state reflection signal waveform of each photovoltaic component, including: based on each state reflection signal waveform, obtaining a first distance between each photovoltaic component and a first signal transmission device, and a second distance between each photovoltaic component and a second signal transmission device; based on each state reflection signal waveform, obtaining an initial three-dimensional image of each photovoltaic component through time domain reflection imaging processing; based on the first distance, second distance and initial three-dimensional image of each photovoltaic component, determining a target position and a target three-dimensional image of each photovoltaic component; based on each state reflection signal waveform and the target three-dimensional image of each photovoltaic component, establishing a photovoltaic array state information library.

[0017] The photovoltaic array status information library established in this application includes the state reflection signal waveform and three-dimensional image of each photovoltaic module in various states, which provides a detection basis for subsequent photovoltaic array fault detection.

[0018] In an optional embodiment, based on the photovoltaic array status information library and the status reflection signal of each photovoltaic module, fault detection is performed on the photovoltaic array to obtain a fault detection result of the photovoltaic array, including: determining the number of each photovoltaic module in the photovoltaic array status information library based on the target position of each photovoltaic module; based on the photovoltaic array status information library, the number of each photovoltaic module and the target status reflection signal waveform, fault detection is performed on each photovoltaic module to obtain a fault detection result of each photovoltaic module; based on the fault detection result of each photovoltaic module, the fault detection result of the photovoltaic array is determined.

[0019] The present application obtains the fault detection results of the photovoltaic array by matching the state reflection signals of each photovoltaic component in each state in the photovoltaic array with the photovoltaic array state information library, thereby realizing all-weather intelligent fault detection of the photovoltaic array, improving the efficiency of fault detection, and reducing the cost of fault detection.

[0020] In the second aspect, the present application provides a photovoltaic array fault detection device, wherein the photovoltaic array includes at least one photovoltaic component, and the photovoltaic array is respectively connected to a signal transmission system and a filtering system, the signal transmission system includes a first signal transmission device connected to one end of the photovoltaic array, and a second signal transmission device connected to the other end of the photovoltaic array; the device includes: a first acquisition module for acquiring a photovoltaic array status information library; a sending module for using the first signal transmission device and the second signal transmission device in the signal transmission system to send a step signal to the photovoltaic array respectively; a second acquisition module for acquiring a status reflection signal of each photovoltaic component in the photovoltaic array based on the step signal; a filtering processing module for sending the status reflection signal of each photovoltaic component to the filtering system for filtering processing to obtain a target status reflection signal waveform diagram of each photovoltaic component; a detection module for performing fault detection on the photovoltaic array based on the photovoltaic array status information library and the status reflection signal of each photovoltaic component to obtain a fault detection result of the photovoltaic array.

[0021] In a third aspect, the present application provides a computer device comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the photovoltaic array fault detection method of the first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0022] In a fourth aspect, the present application provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the photovoltaic array fault detection method of the first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] FIG1 is a schematic flow chart of a photovoltaic array fault detection method according to an embodiment of the present application;

[0025] FIG2 is a schematic flow chart of another photovoltaic array fault detection method according to an embodiment of the present application;

[0026] FIG3 is a flow chart of another photovoltaic array fault detection method according to an embodiment of the present application;

[0027] FIG4 is a flow chart of yet another photovoltaic array fault detection method according to an embodiment of the present application;

[0028] FIG5 is a flow chart of a photovoltaic array fault detection method based on time domain reflectometry according to an embodiment of the present application;

[0029] FIG6 is a structural block diagram of a photovoltaic array fault detection device according to an embodiment of the present application;

[0030] FIG. 7 is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present application. DETAILED DESCRIPTION

[0031] To make the purpose, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of this application.

[0032] Photovoltaic arrays are often installed in places with relatively harsh natural environments, such as deserts, wastelands and other areas. Therefore, the photovoltaic components and lines inside them are often exposed to solar radiation, rain, fog, rain and other extreme weather conditions, as well as line aging, wear and tear. Therefore, an embodiment of the present application provides a photovoltaic array fault detection method, which is combined with a signal transmission system and a filtering system connected to the photovoltaic array. By matching the state reflection signals of each photovoltaic component in the photovoltaic array in each state with the photovoltaic array state information library, the effect of all-weather intelligent fault detection of the photovoltaic array can be achieved.

[0033] According to an embodiment of the present application, an embodiment of a photovoltaic array fault detection method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0034] In this embodiment, a photovoltaic array fault detection method is provided, which combines a signal transmission system and a filtering system for fault detection. The signal transmission system includes a first signal transmission device connected to one end of the photovoltaic array and a second signal transmission device connected to the other end of the photovoltaic array. Figure 1 is a flow chart of the photovoltaic array fault detection method according to an embodiment of the present application. As shown in Figure 1, the process includes the following steps:

[0035] Step S101: Acquire a photovoltaic array status information database.

[0036] The photovoltaic array includes at least one photovoltaic component.

[0037] Specifically, the photovoltaic array status information library is a pre-built database containing relevant status information of each photovoltaic component in the photovoltaic array.

[0038] Step S102: using the first signal transmission device and the second signal transmission device in the signal transmission system to respectively send a step signal to the photovoltaic array.

[0039] The photovoltaic array is connected to the signal transmission system, and the signal transmission system sends step signals to the photovoltaic array in a cross-cycle manner.

[0040] Specifically, each signal transmission device includes a signal sending device and a signal receiving device.

[0041] A periodic step signal can be sent to the photovoltaic array through the first signal transmission device and the second signal transmission device at both ends of the photovoltaic array.

[0042] First, the signal sending devices in the signal transmission devices at both ends of the photovoltaic array initialize the periodic signal transmission instruction, and then the signal sending device in the first signal transmission device at the left end of the photovoltaic array sends a step signal to the photovoltaic array.

[0043] Secondly, when the signal receiving device in the second signal transmission device at the right end of the photovoltaic array receives the step signal output by the photovoltaic array, a periodic step signal sending instruction is generated according to the received step signal, and under the control of the periodic step signal sending instruction, the signal sending device in the second signal transmission device sends a step signal to the photovoltaic component.

[0044] Specifically, after the signal transmission device at both ends of the photovoltaic array receives the signal, it first determines the frequency of the received signal, and then determines whether it is a reflected signal of the step signal sent by the signal receiving end. If it is determined to be the step signal of the end where it is located, it is temporarily saved. If it is determined not to be the step signal of the end where it is located, a periodic step signal instruction is generated.

[0045] Optionally, a signal length threshold is set in the signal transmission device at both ends of the photovoltaic array. Therefore, upon receiving a signal of a specific signal frequency, the signal transmission device first determines whether the signal length is greater than the signal length threshold. If the signal length is determined to be less than or equal to the signal length threshold, the signal segment is automatically ignored. If the signal length is determined to be greater than the signal length threshold, the signal transmission device further determines, based on the signal frequency, whether it is a reflection of the step signal sent by the signal receiving device.

[0046] Step S103 : acquiring a status reflection signal of each photovoltaic component in the photovoltaic array based on the step signal.

[0047] Specifically, due to the various morphological defects of each photovoltaic module in the photovoltaic array, such as line loss defects, appearance defects or internal parts defects, the step signal is reflected in stages in the photovoltaic array, that is, when the step signal passes through a normal photovoltaic module or a defective photovoltaic module, a part of it will be reflected back to its sending end.

[0048] Therefore, by sending a step signal to the photovoltaic array through the signal transmission system, a state reflection signal of each photovoltaic component in the photovoltaic array in the current state can be obtained.

[0049] Step S104 : sending the state reflection signal of each photovoltaic module to a filtering system for filtering processing to obtain a waveform diagram of the target state reflection signal of each photovoltaic module.

[0050] Here, the filter system refers to a filtering device used to remove unnecessary frequencies from a signal.

[0051] Specifically, the state reflection signal is filtered by the filtering system to obtain a waveform diagram of the reflection signal reflecting the current state of each photovoltaic component in the current photovoltaic array, that is, a target state reflection signal waveform diagram.

[0052] Step S105 : Based on the photovoltaic array state information library and the target state reflection signal waveform of each photovoltaic module, fault detection is performed on the photovoltaic array to obtain a fault detection result of the photovoltaic array.

[0053] Specifically, the target state reflection signal waveform of each photovoltaic component in the photovoltaic array is matched with the photovoltaic array state information library, and whether the corresponding photovoltaic component has a fault is determined based on the matching result. Further, the fault detection result of the photovoltaic array can be obtained.

[0054] The photovoltaic array fault detection method provided in this embodiment matches the state reflection signal of each photovoltaic module in the photovoltaic array with the photovoltaic array state information database, thereby determining the fault state of each photovoltaic module in the photovoltaic array and obtaining the photovoltaic array fault detection results. This method realizes all-weather intelligent fault detection for the photovoltaic array, improves the efficiency of fault detection, and reduces the cost of fault detection. Furthermore, signal transmission devices at the left and right ends of the photovoltaic array transmit step signals to the photovoltaic array in a cross-wise manner, thereby realizing uninterrupted fault detection of photovoltaic modules in the photovoltaic array. Because signal transmission devices are provided at both ends of the photovoltaic array, the photovoltaic modules in the photovoltaic array are fully detected at both ends, which to a certain extent improves the accuracy of fault detection.

[0055] In this embodiment, a photovoltaic array fault detection method is provided, which combines a signal transmission system and a filtering system for fault detection. The signal transmission system includes a first signal transmission device connected to one end of the photovoltaic array and a second signal transmission device connected to the other end of the photovoltaic array. Figure 2 is a flow chart of the photovoltaic array fault detection method according to an embodiment of the present application. As shown in Figure 2, the flow chart includes the following steps:

[0056] Step S201: Acquire a photovoltaic array status information database.

[0057] Specifically, the above step S201 includes:

[0058] Step S2011: sending a step signal to the photovoltaic array using a signal transmission system, and acquiring at least one state reflection signal of each photovoltaic module in the photovoltaic array based on the step signal.

[0059] Specifically, referring to the description in step S102 of the embodiment shown in FIG. 1 , the state reflection signal of each photovoltaic component in the photovoltaic array in different states can be obtained.

[0060] Step S2012: Send each state reflection signal of each photovoltaic module to a filtering system for filtering processing to obtain at least one state reflection signal waveform of each photovoltaic module.

[0061] Specifically, referring to the description of step S103 in the embodiment shown in FIG. 1 , a waveform diagram reflecting the reflection signal of each photovoltaic component in the photovoltaic array in different states can be obtained.

[0062] The different states of the photovoltaic module may include a complete photovoltaic module state, a line missing state, a parts missing state, and a shell damaged state, and each state has at least one corresponding reflection signal waveform diagram.

[0063] Step S2013: establishing a photovoltaic array state information library based on each state reflection signal waveform of each photovoltaic module.

[0064] Specifically, the state reflection signal waveforms of each photovoltaic component in different states are stored in the photovoltaic array state information library, which provides a detection basis for subsequent photovoltaic array detection.

[0065] In some optional implementations, the above step S2013 includes:

[0066] Step a1: Based on the waveform diagram of the reflection signal in each state, a first distance between each photovoltaic component and the first signal transmission device and a second distance between each photovoltaic component and the second signal transmission device are obtained.

[0067] Step a2: Based on the waveform of the reflection signal of each state, an initial three-dimensional image of each photovoltaic module is obtained by processing it using a time domain reflection imaging method.

[0068] Step a3: determining a target position and a target three-dimensional image of each photovoltaic component based on the first distance, the second distance, and the initial three-dimensional image of each photovoltaic component.

[0069] Step a4: establishing a photovoltaic array state information library based on the reflection signal waveform diagram of each state of each photovoltaic module and the target three-dimensional image.

[0070] First, the physical position of the photovoltaic module in the photovoltaic array is located according to the state reflection signal waveform.

[0071] Specifically, the propagation speed of the step signal and the time point when the signal transmission devices at both ends of the photovoltaic array send the step signal can be obtained according to the state reflection signal waveform diagram.

[0072] Optionally, the first distance between the photovoltaic assembly and the first signal transmission device and the second distance between the photovoltaic assembly and the second signal transmission device are calculated using the following equations (1) and (2), respectively:

[0073] Where: H L,k Indicates the number is g k A first distance between the photovoltaic assembly and the first signal transmission device; H R,k Indicates the number is g k The second distance between the photovoltaic component and the second signal transmission device; v represents the propagation speed of the step signal in the photovoltaic array ； t i,L represents the state reflection signal received by the first signal transmission device at time i; t i , R represents the state reflection signal received by the second signal transmission device at time i; t 0,L represents the time point when the first signal transmission device sends the step signal; t 0,R Indicates the time point when the second signal transmission device sends the step signal.

[0074] Optionally, an initial three-dimensional image of the corresponding photovoltaic component is acquired according to the state reflection signal waveform diagram and a time domain reflection imaging method.

[0075] Optionally, based on the initial three-dimensional images of the photovoltaic components with the same number obtained at the left and right ends in adjacent cycles, and their physical positions (first distance and second distances) relative to the signal receiving devices at the left and right ends, the position of the corresponding photovoltaic component in the photovoltaic array, i.e., the target position, and the real-time three-dimensional image, i.e., the target three-dimensional image, are determined.

[0076] Finally, a photovoltaic array state information library is established based on the state reflection signal waveforms of each photovoltaic module in the photovoltaic array under various states and the target three-dimensional image.

[0077] The photovoltaic array status information library may include the number of each photovoltaic component in the photovoltaic array, its physical position in the photovoltaic array, the time point when the signal receiving devices at the left and right ends receive the corresponding reflected signal, and three-dimensional images in various states and corresponding reflected signal waveforms. The number of each photovoltaic component in the photovoltaic array is pre-set, such as g1, g2, ..., g k , k can be a natural number greater than 0.

[0078] In step S202, the first signal transmission device and the second signal transmission device in the signal transmission system are used to send a step signal to the photovoltaic array. For details, please refer to step S102 of the embodiment shown in FIG1 , which will not be described in detail here.

[0079] Step S203: Acquire a state reflection signal of each photovoltaic module in the photovoltaic array based on the step signal. For details, please refer to step S103 of the embodiment shown in FIG1 , which will not be described in detail here.

[0080] In step S204, the state reflection signal of each photovoltaic module is sent to the filtering system for filtering processing to obtain the target state reflection signal waveform of each photovoltaic module. For details, please refer to step S104 of the embodiment shown in Figure 1, which will not be repeated here.

[0081] Step S205: Based on the PV array state information library and the target state reflection signal waveform of each PV module, the PV array is fault-detected to obtain a PV array fault detection result. For details, please refer to step S105 of the embodiment shown in FIG1 , which will not be described in detail here.

[0082] The photovoltaic array fault detection method provided in this embodiment establishes a photovoltaic array state information library based on the reflection signal waveforms of each photovoltaic component in each state within the photovoltaic array, and then matches the target state reflection signal waveform of each photovoltaic component in each state with the photovoltaic array state information library. The current state of the corresponding photovoltaic array can be determined and corresponding maintenance measures can be generated. If the corresponding reflection signal waveform is not matched, the reflection signal waveform is recorded, thereby implementing all-weather intelligent fault detection for the photovoltaic array, improving the efficiency of fault detection, and reducing the cost of fault detection.

[0083] In this embodiment, a photovoltaic array fault detection method is provided, which combines a signal transmission system and a filtering system for fault detection. The signal transmission system includes a first signal transmission device connected to one end of the photovoltaic array and a second signal transmission device connected to the other end of the photovoltaic array. Figure 3 is a flow chart of the photovoltaic array fault detection method according to an embodiment of the present application. As shown in Figure 3, the flow chart includes the following steps:

[0084] Step S301: Acquire a photovoltaic array status information database. For details, please refer to step S201 of the embodiment shown in FIG2 , which will not be described in detail here.

[0085] In step S302, the first signal transmission device and the second signal transmission device in the signal transmission system are used to send a step signal to the photovoltaic array. For details, please refer to step S102 of the embodiment shown in FIG1 , which will not be described in detail here.

[0086] Step S303: Acquire the state reflection signal of each photovoltaic module in the photovoltaic array based on the step signal. Please refer to step S103 of the embodiment shown in FIG1 for details, which will not be repeated here.

[0087] Step S304 : sending the state reflection signal of each photovoltaic module to a filtering system for filtering processing to obtain a waveform diagram of the target state reflection signal of each photovoltaic module.

[0088] Specifically, the above step S304 includes:

[0089] Step S3041: Send the state reflection signal of each photovoltaic module to a first high-pass filter for filtering to obtain a first state reflection signal waveform and a first signal-to-noise ratio value.

[0090] The signal-to-noise ratio value represents the ratio of the strength of the received useful signal to the strength of the received interference signal (noise and interference).

[0091] Specifically, the filtering system includes a first high-pass filter and a second high-pass filter, and the first high-pass filter and the second high-pass filter are provided with the same transfer function.

[0092] The state reflection signal of each photovoltaic module is sent to the first high-pass filter for filtering, so as to obtain a corresponding first state reflection signal waveform and a first signal-to-noise ratio value.

[0093] Step S3042 : Sending the state reflection signal of each photovoltaic module filtered by the first high-pass filter to a second high-pass filter for filtering to obtain a second state reflection signal waveform and a second signal-to-noise ratio value.

[0094] Specifically, the state reflection signal filtered by the first high-pass filter is sent to the second high-pass filter for filtering, and a second state reflection signal waveform and a second signal-to-noise ratio value corresponding to the state reflection signal filtered by the second high-pass filter are obtained.

[0095] Step S3043 : Compare the first signal-to-noise ratio value with a preset signal-to-noise ratio threshold, and compare the second state reflection signal waveform with the first state reflection signal waveform to obtain a difference value.

[0096] Specifically, the first signal-to-noise ratio value is compared with a preset signal-to-noise ratio threshold, and at the same time, the second state reflection signal waveform is compared with the first state reflection signal waveform to obtain a corresponding difference value.

[0097] Step S3044: When the first signal-to-noise ratio value is less than the preset signal-to-noise ratio threshold and the difference value is less than the preset difference threshold, the signal cutoff frequencies of the first high-pass filter and the second high-pass filter are adjusted respectively, and based on the adjusted first high-pass filter and the second high-pass filter, the state reflection signal of each photovoltaic component is processed until the second signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, and the adjustment is stopped, and the target state reflection signal waveform is obtained.

[0098] In this example, the preset difference threshold is 3%.

[0099] Specifically, if the first signal-to-noise ratio value is less than a preset signal-to-noise ratio threshold, and the difference between the second-state reflection signal waveform and the first-state reflection signal waveform is less than 3%, the filtering state of the first high-pass filter and the second high-pass filter is determined to be normal. Optionally, the signal cutoff frequencies of the first and second high-pass filters are adjusted, and the original state reflection signal of each photovoltaic module is filtered again through the two high-pass filters. Adjustment is stopped until the second signal-to-noise ratio value obtained is greater than or equal to the preset signal-to-noise ratio threshold, and the corresponding target state reflection signal waveform is obtained.

[0100] Step S3045 : When the first signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold and the difference value is less than the preset difference threshold, the second-state reflection signal waveform is used as the target-state reflection signal waveform.

[0101] Specifically, if the first signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, and the difference between the second-state reflection signal waveform and the first-state reflection signal waveform is less than 3%, the filtering is judged to be completed at this time, and the obtained second-state reflection signal waveform is directly used as the target state reflection signal waveform.

[0102] By adjusting the signal cutoff frequencies of the first high-pass filter and the second high-pass filter in the filtering system, the efficiency and quality of filtering the state reflection signal are improved.

[0103] In some optional implementations, after step S3043, the above step S304 further includes:

[0104] Step S3046 : When the first signal-to-noise ratio value is less than the preset signal-to-noise ratio threshold and the difference value is greater than or equal to the preset difference threshold, it is determined that the first high-pass filter and the second high-pass filter are faulty.

[0105] Specifically, if the first signal-to-noise ratio value is less than the preset signal-to-noise ratio threshold, and the difference between the second state reflection signal waveform and the first state reflection signal waveform is greater than 3%, it means that the filtered state reflection signals do not meet the requirements. At this time, it is judged that the states of the first high-pass filter and the second high-pass filter are abnormal and need to be repaired.

[0106] Step S3047: When the first signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, and the difference value is greater than the preset difference threshold, it is determined that the first high-pass filter and the second high-pass filter are faulty.

[0107] Specifically, if the first signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, and the difference between the second state reflection signal waveform and the first state reflection signal waveform is greater than 3%, it means that the filtered state reflection signals do not meet the requirements. At this time, it is judged that the states of the first high-pass filter and the second high-pass filter are abnormal and need to be repaired.

[0108] Optionally, the reflected signal is re-filtered using the first high-pass filter and the second high-pass filter after the maintenance process until a target state reflected signal waveform diagram that meets the conditions is obtained.

[0109] Specifically, when the difference between the second state reflection signal waveform and the first state reflection signal waveform is greater than 3%, it is determined that the first high-pass filter and the second high-pass filter are abnormal and need to be repaired.

[0110] Step S305: Based on the PV array state information library and the target state reflection signal waveform of each PV module, the PV array is fault-detected to obtain a PV array fault detection result. For details, please refer to step S105 of the embodiment shown in FIG1 , which will not be described in detail here.

[0111] The photovoltaic array fault detection method provided in this embodiment determines whether an abnormality occurs in the high-pass filter by setting up two high-pass filters with the same transfer function, passing the reflected signal of the step signal through the two high-pass filters in sequence, and then comparing the reflected signal waveforms obtained from the two. At the same time, a signal-to-noise ratio threshold is set, and the signal-to-noise ratio value of the obtained reflected signal waveform is compared with the signal-to-noise ratio threshold, and then the signal cutoff frequency of the high-pass filter is adjusted multiple times until the optimal signal cutoff frequency is found, thereby improving the efficiency and quality of the reflected signal filtering to a certain extent.

[0112] In this embodiment, a photovoltaic array fault detection method is provided, which combines a signal transmission system and a filtering system for fault detection. The signal transmission system includes a first signal transmission device connected to one end of the photovoltaic array and a second signal transmission device connected to the other end of the photovoltaic array. FIG4 is a flow chart of the photovoltaic array fault detection method according to an embodiment of the present application. As shown in FIG4, the flow chart includes the following steps:

[0113] Step S401: Acquire a photovoltaic array status information database. For details, please refer to step S201 of the embodiment shown in FIG2 , which will not be described in detail here.

[0114] In step S402, the first signal transmission device and the second signal transmission device in the signal transmission system are used to send a step signal to the photovoltaic array. For details, please refer to step S102 of the embodiment shown in FIG1 , which will not be described in detail here.

[0115] Step S403 : When the first signal transmission device does not receive the status reflection signal within a preset unit time, the first signal transmission device sends a step signal sending request instruction to the second signal transmission device.

[0116] Specifically, a signal reception early warning mechanism is provided in the first signal transmission device and the second signal transmission device at both ends of the photovoltaic array.

[0117] If the first signal transmission device does not receive the status reflection signal within the preset unit time, a step signal sending request instruction is sent to the second signal transmission device.

[0118] Optionally, if the second signal transmission device does not receive the status reflection signal within a preset unit time, it may also send a step signal sending request instruction to the first signal transmission device.

[0119] Optionally, whether to send a step signal sending request instruction to the other end may also be determined based on whether a step signal sent by the signal transmission device at the other end is received.

[0120] Step S404: determining whether the first signal transmission device has received a response instruction sent by the second signal transmission device.

[0121] Specifically, after the first signal transmission device sends the step signal sending request instruction, it is further determined whether the second signal transmission device sends a response instruction to the first signal transmission device.

[0122] Step S405: When the first signal transmission device does not receive the response instruction, it is determined that the second signal transmission device fails.

[0123] Specifically, if the first signal transmission device does not receive the response instruction, it means that the second signal transmission device has not received the step signal sending request instruction sent by the first signal transmission device. Further, it can be determined that the second signal transmission device has failed.

[0124] In step S406 , when the first signal transmission device receives the response instruction and the first signal transmission device does not receive the status reflection signal within the preset unit time, it is determined that the second signal transmission device fails.

[0125] Specifically, if the first signal transmission device receives a response instruction, it means that the second signal transmission device has received the step signal sending request instruction sent by the first signal transmission device. At this time, if the first signal transmission device still does not receive the status reflection signal within the preset unit time, it can be determined that the second signal transmission device has failed.

[0126] Optionally, if the first signal transmission device receives the status reflection signal sent by the second signal transmission device, it indicates that the status of the second signal transmission device is normal, and no operation is performed at this time.

[0127] Step S407: Acquire the state reflection signal of each photovoltaic module in the photovoltaic array based on the step signal. For details, please refer to step S103 of the embodiment shown in FIG1 , which will not be described in detail here.

[0128] In step S408, the state reflection signal of each photovoltaic module is sent to the filtering system for filtering processing to obtain the target state reflection signal waveform of each photovoltaic module. For details, please refer to step S304 of the embodiment shown in Figure 3, which will not be repeated here.

[0129] Step S409 : Based on the photovoltaic array state information library and the target state reflection signal waveform of each photovoltaic module, fault detection is performed on the photovoltaic array to obtain a fault detection result of the photovoltaic array.

[0130] Specifically, the above step S409 includes:

[0131] S4091: Based on the target position of each photovoltaic component, determine the serial number of each photovoltaic component in the photovoltaic array state information library.

[0132] The photovoltaic array status information database includes the serial number of each photovoltaic module in the photovoltaic array and its physical position in the photovoltaic array.

[0133] Specifically, by matching the target position of each photovoltaic component in the photovoltaic array with the target position of each photovoltaic component included in the photovoltaic array status information library, the corresponding photovoltaic component can be determined. Further, the number of the determined photovoltaic component can be obtained in the photovoltaic array status information library.

[0134] S4092 : Based on the photovoltaic array state information library, the number of each photovoltaic module and the target state reflection signal waveform, perform fault detection on each photovoltaic module to obtain a fault detection result for each photovoltaic module.

[0135] Specifically, the number and target state reflection signal waveform of each photovoltaic module are matched with the number and state reflection signal waveform of the photovoltaic modules included in the photovoltaic array state information library, and then the current state of the corresponding photovoltaic module can be determined according to the comparison result.

[0136] If it is determined that the current state of the PV module is normal, no operation is performed;

[0137] If it is determined that the current state of the photovoltaic component is any state other than the normal state, a maintenance request is generated and sent to the relevant maintenance personnel, where the maintenance request includes the number of the photovoltaic component, the physical location in the photovoltaic array, the current state, and a three-dimensional image in the current state.

[0138] Optionally, when using the target state reflection signal waveform to match the photovoltaic array state information library, if there is a reflection signal waveform whose difference from the reflection signal waveform to be matched is within 5%, it is judged that the two are consistent. If there is no reflection signal waveform whose difference from the reflection signal waveform to be matched is within 5%, a three-dimensional image is first generated based on the reflection signal waveform to be matched, and then its current state type is determined and a maintenance request is generated, and the reflection signal waveform is recorded in the photovoltaic array state information library.

[0139] S4093: Determine a fault detection result of the photovoltaic array based on the fault detection result of each photovoltaic component.

[0140] Specifically, the photovoltaic array is composed of at least one photovoltaic component. Therefore, the fault detection result of the photovoltaic array can be obtained according to the fault detection result of each photovoltaic component.

[0141] The photovoltaic array fault detection method provided in this embodiment matches the target state reflection signal waveform with the photovoltaic array state information library, thereby determining the current state of the corresponding photovoltaic array and generating corresponding maintenance measures. If the corresponding reflection signal waveform is not matched, the reflection signal waveform is recorded, thereby implementing all-weather intelligent fault detection for the photovoltaic array, improving the efficiency of fault detection, and reducing the cost of fault detection.

[0142] In one embodiment, a photovoltaic array fault detection method based on time domain reflectometry is provided, as shown in FIG5 , including the following steps:

[0143] Step 1: The signal sending device periodically sends a step signal to the photovoltaic array, thereby obtaining the reflection signal of each photovoltaic module in the photovoltaic array in various states;

[0144] Specifically, the signal sending device is provided with a periodic signal transmission instruction, and then the signal sending device periodically sends a step signal to the photovoltaic array;

[0145] It should be noted that a signal transmitter and a signal receiver are provided at both ends of the photovoltaic array, and the step signal transmission cycles of the signal transmitters at both ends of the photovoltaic array are cross-linked, that is, when the step signal sent by the signal transmitter at one end reaches the signal receiver at the other end, the signal transmitter at the other end starts to send a step signal, and the signal frequencies of the step signals sent by the signal transmitters at the two ends are different;

[0146] The following describes the cross-sending of step signals by a signal sending device through an embodiment:

[0147] The signal sending devices at both ends of the photovoltaic array initialize the periodic signal transmission instruction, and then the signal sending device at the left end sends a step signal to the photovoltaic array;

[0148] Since each photovoltaic module in the photovoltaic array has various defects, such as line loss defects, appearance defects or internal parts defects, the step signal is reflected in stages in the photovoltaic array, that is, when the step signal passes through a normal photovoltaic module or a defective photovoltaic module, a part of it will be reflected back to its sending end until the step signal reaches the right end of the photovoltaic array and is received by the signal receiving device at the right end;

[0149] The signal receiving device at the right end first determines the frequency of the received step signal, and then determines whether it is a reflection signal of the step signal sent by the right end. If it is determined to be a reflection signal of the step signal sent by the right end, it passes it through the filter;

[0150] If it is determined that the reflected signal is not the step signal sent from the right end, that is, it is a step signal from the left end, a periodic step signal sending instruction is generated according to the step signal from the left end, and then the signal sending device at the right end sends a step signal to the photovoltaic module;

[0151] It should be noted that the signal receiving devices at both ends of the photovoltaic array are equipped with a signal reception early warning mechanism, that is, if the signal receiving device at any end of the photovoltaic array does not receive the step signal from the other end, or the reflected signal of the step signal at its end within a unit time, then a step signal sending request is sent to the signal sending device at the other end or its end. If the signal receiving device receives a response from the signal sending device but still does not receive the step signal or reflected signal within a unit time, or still does not receive a response from the signal transmitting device, then it is determined that the corresponding signal transmitting device is damaged and a maintenance instruction is sent to the maintenance personnel; if the signal receiving device receives a step signal or reflected signal within a unit time, no operation is performed;

[0152] By cross-sending step signals through the signal sending devices on the left and right ends, uninterrupted fault detection of the photovoltaic components in the photovoltaic array is achieved. Moreover, since signal sending devices and signal receiving devices are provided on the left and right sides of the photovoltaic array, the photovoltaic components in the photovoltaic array can be fully detected at both ends, thereby improving the fault detection accuracy to a certain extent.

[0153] Step 2: Pass the reflected signal through a high-pass filter to obtain a filtered reflected signal waveform;

[0154] Specifically, after receiving the signal, the signal receiving devices at both ends of the photovoltaic array first determine the frequency of the received signal, and then determine whether it is a reflected signal of the step signal sent by the signal receiving end. If it is determined to be the step signal of the end where it is located, it is temporarily stored. If it is determined not to be the step signal of the end where it is located, a periodic step signal instruction is generated.

[0155] It should be noted that the signal receiving devices at both ends of the photovoltaic array are equipped with a signal length threshold. After receiving a signal of a specific signal frequency, the signal receiving device first determines whether its signal length is greater than the signal length threshold. If it is determined that the signal length is less than or equal to the signal length threshold, the signal segment will be automatically ignored. If it is determined that the signal length is greater than the signal length threshold, the signal receiving device will further determine whether it is a reflected signal of the step signal sent by one end of the signal receiving device based on its signal frequency.

[0156] Optionally, for the reflected signal of the step signal sent by one end of the judgment signal receiving device, pass it through two high-pass filters with the same transfer function, and set a signal-to-noise ratio threshold;

[0157] After the reflected signal passes through the first high-pass filter, a reflected signal waveform is obtained, and a first signal-to-noise ratio value thereof is obtained. The first signal-to-noise ratio value is compared with a signal-to-noise ratio threshold value. If the first signal-to-noise ratio value is less than the signal-to-noise ratio threshold value, the reflected signal that has passed through the first high-pass filter is passed through a second high-pass filter. If the difference between the reflected signal waveform obtained by the first high-pass filter and the reflected signal waveform obtained by the second high-pass filter is less than 3%, it is determined that the filtering state of the high-pass filter is normal, and the signal cutoff frequency of the high-pass filter is adjusted and the original reflected signal is passed through the two high-pass filters again until the signal-to-noise ratio value of the obtained reflected signal waveform is greater than or equal to the signal-to-noise ratio threshold value. If the difference is greater than 3%, it is determined that the state of the high-pass filter is abnormal and needs to be repaired.

[0158] If it is determined that the signal-to-noise ratio of the reflected signal waveform obtained by the first high-pass filter is greater than or equal to the signal-to-noise ratio threshold, the reflected signal obtained by the first high-pass filter is passed through the second high-pass filter. If the difference between the two reflected signal waveforms is less than 3%, the filtering is determined to be complete and the reflected signal waveform is saved. If the difference is greater than 3%, the two high-pass filters are repaired and the reflected signal is filtered again.

[0159] By setting up two high-pass filters with the same transfer function, and passing the reflected signal of the step signal through the two high-pass filters in turn, and then comparing the reflected signal waveforms obtained by the two, it is possible to determine whether there is any abnormality in the high-pass filter; at the same time, a signal-to-noise ratio threshold is set, and the signal-to-noise ratio value of the obtained reflected signal waveform is compared with the signal-to-noise ratio threshold, and then the signal cutoff frequency of the high-pass filter is adjusted multiple times until the optimal signal cutoff frequency is found, which improves the efficiency and quality of filtering the reflected signal to a certain extent.

[0160] Step 3: Establishing a photovoltaic array state information database based on the reflection signal waveforms of the photovoltaic modules in each state in the photovoltaic array;

[0161] Specifically, a three-dimensional image of the corresponding photovoltaic module is obtained based on the reflection signal waveform and the time domain reflection imaging method, and the photovoltaic modules are numbered, such as g1, g2, ..., gk, where k can be a natural number greater than 0. The physical position of the photovoltaic module in the photovoltaic array is located based on the reflection signal waveform. The process of obtaining the physical position of the photovoltaic module includes:

[0162] First, calculate the distance between the photovoltaic modules and the left and right ends. The calculation formula refers to the above equations (1) and (2).

[0163] Based on the three-dimensional images of the photovoltaic components with the same number obtained at the left and right ends in adjacent cycles, and their physical positions relative to the signal receiving devices at the left and right ends, the position of the corresponding photovoltaic components in the photovoltaic array and the real-time three-dimensional image are determined;

[0164] Optionally, a photovoltaic array state information library is established based on the reflection signal waveforms and three-dimensional graphics of each photovoltaic module in each state in the photovoltaic array;

[0165] Among them, the photovoltaic array status information library includes the number of each photovoltaic module in the photovoltaic array, its physical position in the photovoltaic array, the time point when the signal receiving devices at the left and right ends receive the corresponding reflected signal, and the three-dimensional images under various states and the corresponding reflected signal waveforms. The various states of the photovoltaic modules include the complete state of the photovoltaic module, the line missing state, the parts missing state and the shell damaged state, and each state has corresponding several reflected signal waveforms.

[0166] Step 4: Pass the new reflected signal through a high-pass filter to obtain the corresponding reflected signal waveform, and match it with the photovoltaic array state information library to obtain the current state of the photovoltaic component corresponding to the reflected signal;

[0167] Specifically, the signal sending devices at the left and right ends periodically send step signals to the photovoltaic array in sequence, thereby obtaining reflection signals based on each photovoltaic component in the photovoltaic array, and then passing the reflection signals through two high-pass filters in sequence to obtain corresponding reflection signal waveforms;

[0168] At the same time, according to the time when the signal receiving unit receives the reflected signal, the distance of the corresponding photovoltaic module relative to the left and right ends is obtained, and then its physical position in the photovoltaic array is determined. The number of the corresponding photovoltaic module is obtained from the photovoltaic array status information library according to the physical position;

[0169] According to the number of the photovoltaic module and the reflected signal waveform obtained by the high-pass filter, the photovoltaic array status information database is matched to determine the current status of the corresponding photovoltaic module;

[0170] If the current status of the PV module is judged to be normal, no operation is performed;

[0171] If the current state of the PV module is determined to be any state other than the normal state, a maintenance request is generated and sent to the relevant maintenance personnel, where the maintenance request includes the number of the PV module, the physical location in the PV array, the current state, and a three-dimensional image of the current state;

[0172] It should be noted that when matching the photovoltaic array status information library through the reflection signal waveform, if there is a reflection signal waveform with a difference of less than 5% from the reflection signal waveform to be matched, it is judged that the two are consistent. If there is no reflection signal waveform with a difference of less than 5% from the reflection signal waveform to be matched, a three-dimensional image is first generated based on the reflection signal waveform to be matched, and then its current status type is determined and a maintenance request is generated. At the same time, the reflection signal waveform is recorded in the photovoltaic array status information library.

[0173] This embodiment also provides a photovoltaic array fault detection device for implementing the aforementioned embodiments and alternative implementations. Details already described will not be repeated. As used below, the term "module" may refer to a combination of software and / or hardware that implements a predetermined function. While the devices described in the following embodiments are preferably implemented using software, implementation using hardware, or a combination of software and hardware, is also possible and contemplated.

[0174] This embodiment provides a photovoltaic array fault detection device. The photovoltaic array includes at least one photovoltaic module, and the photovoltaic array is connected to a signal transmission system and a filtering system respectively. The signal transmission system includes a first signal transmission device connected to one end of the photovoltaic array, and a second signal transmission device connected to the other end of the photovoltaic array, as shown in FIG6 , including:

[0175] The first acquisition module 601 is used to acquire a photovoltaic array status information database.

[0176] The sending module 602 is configured to send a step signal to the photovoltaic array using the first signal transmission device and the second signal transmission device in the signal transmission system respectively.

[0177] The second acquisition module 603 is configured to acquire a status reflection signal of each photovoltaic component in the photovoltaic array based on the step signal.

[0178] The filtering processing module 604 is configured to send the state reflection signal of each photovoltaic module to the filtering system for filtering processing to obtain a target state reflection signal waveform of each photovoltaic module.

[0179] The detection module 605 performs fault detection on the photovoltaic array based on the photovoltaic array state information library and the target state reflection signal waveform of each photovoltaic module to obtain a fault detection result of the photovoltaic array.

[0180] In some optional implementations, the photovoltaic array fault detection device further includes:

[0181] A first sending module is configured to send a step signal sending request instruction to the second signal transmission device when the first signal transmission device does not receive a status reflection signal within a preset unit time;

[0182] a determination module, configured to determine whether the first signal transmission device has received a response instruction to the step signal transmission request instruction sent by the second signal transmission device;

[0183] a first determining module, configured to determine that a failure occurs in the second signal transmission device when the first signal transmission device does not receive a response instruction;

[0184] The second determining module is configured to determine that a fault occurs in the second signal transmission device when the first signal transmission device receives a response instruction and the first signal transmission device does not receive a status reflection signal within a preset unit time.

[0185] In some optional implementations, the first acquisition module 601 includes:

[0186] The sending and acquiring unit is configured to send a step signal to the photovoltaic array using a signal transmission system, and acquire at least one state reflection signal of each photovoltaic component in the photovoltaic array based on the step signal.

[0187] The first sending unit is configured to send each state reflection signal of each photovoltaic module to the filtering system for filtering processing to obtain at least one state reflection signal waveform diagram of each photovoltaic module.

[0188] The establishing unit is used to establish a photovoltaic array state information library based on each state reflection signal waveform diagram of each photovoltaic component.

[0189] In some optional implementations, the filtering processing module 604 includes:

[0190] A second sending unit is configured to send the state reflection signal of each photovoltaic module to a first high-pass filter for filtering to obtain a first state reflection signal waveform and a first signal-to-noise ratio value;

[0191] a third sending unit, configured to send the state reflection signal of each photovoltaic module filtered by the first high-pass filter to a second high-pass filter for filtering, to obtain a second state reflection signal waveform and a second signal-to-noise ratio value;

[0192] a comparing unit, configured to compare the first signal-to-noise ratio value with a preset signal-to-noise ratio threshold, and compare the second-state reflection signal waveform with the first-state reflection signal waveform to obtain a difference value;

[0193] a processing unit, configured to adjust the signal cutoff frequencies of the first high-pass filter and the second high-pass filter, respectively, when the first signal-to-noise ratio value is less than a preset signal-to-noise ratio threshold and the difference value is less than a preset difference threshold, and process the state reflection signal of each photovoltaic module based on the adjusted first high-pass filter and the second high-pass filter, stopping the adjustment until the second signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, and obtaining a target state reflection signal waveform;

[0194] The first determining unit is configured to use the second-state reflection signal waveform as the target-state reflection signal waveform when the first signal-to-noise ratio value is greater than or equal to a preset signal-to-noise ratio threshold and the difference value is less than the preset difference threshold.

[0195] In some optional implementations, the filtering processing module 604 further includes:

[0196] a second determining unit, configured to determine that a failure occurs in the first high-pass filter and the second high-pass filter when the first signal-to-noise ratio value is less than a preset signal-to-noise ratio threshold and the difference value is greater than or equal to the preset difference threshold;

[0197] The third determining unit is configured to determine that a failure occurs in the first high-pass filter and the second high-pass filter when the first signal-to-noise ratio value is greater than or equal to a preset signal-to-noise ratio threshold and the difference value is greater than a preset difference threshold.

[0198] In some optional embodiments, the establishing unit includes:

[0199] an acquisition subunit, configured to acquire a first distance between each photovoltaic assembly and the first signal transmission device and a second distance between each photovoltaic assembly and the second signal transmission device based on the waveform diagram of the reflection signal in each state;

[0200] A processing subunit is used to obtain an initial three-dimensional image of each photovoltaic module based on the waveform of the reflection signal of each state through time domain reflection imaging;

[0201] a determination subunit, configured to determine a target position and a target three-dimensional image of each photovoltaic component based on the first distance, the second distance, and the initial three-dimensional image of each photovoltaic component;

[0202] A subunit is established for establishing a photovoltaic array state information library based on the reflection signal waveform diagram of each state of each photovoltaic component and the target three-dimensional image.

[0203] In some optional implementations, the detection module 605 includes:

[0204] a fourth determining unit, configured to determine a serial number of each photovoltaic component in a photovoltaic array state information database based on a target position of each photovoltaic component;

[0205] A detection unit is used to perform fault detection on each photovoltaic module based on the photovoltaic array state information library, the number of each photovoltaic module and the target state reflection signal waveform diagram to obtain a fault detection result for each photovoltaic module;

[0206] The fifth determining unit is configured to determine a fault detection result of the photovoltaic array based on the fault detection result of each photovoltaic component.

[0207] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0208] The photovoltaic array fault detection device in this embodiment is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0209] An embodiment of the present application further provides a computer device having the photovoltaic array fault detection device shown in FIG6 .

[0210] Please refer to Figure 7, which is a structural diagram of a computer device provided by an optional embodiment of the present application. As shown in Figure 7, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. The various components are connected to each other using different buses and can be installed on a common motherboard or installed in other ways as needed. The processor can process instructions executed within the computer device, including instructions stored in or on the memory to display graphical information of a GUI on an external input / output device (such as a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 7 takes a processor 10 as an example.

[0211] The processor 10 may be a central processing unit (CPU), a network processor (NPU), or a combination thereof. The processor 10 may also include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device (PLD) may be a complex programmable logic device (CPLD), a field programmable gate array (FPGA), a general purpose array logic (GAL), or any combination thereof.

[0212] The memory 20 stores instructions that can be executed by at least one processor 10, so as to enable at least one processor 10 to execute the method shown in the above embodiment.

[0213] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and application programs required for at least one function; the data storage area may store data created based on the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely located relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0214] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid-state drive; the memory 20 may also include a combination of the above types of memory.

[0215] The computer device further includes a communication interface 30 for the computer device to communicate with other devices or a communication network.

[0216] The embodiments of the present application also provide a computer-readable storage medium. The above-mentioned method according to the embodiment of the present application can be implemented in hardware, firmware, or implemented as a computer code that can be recorded in a storage medium, or implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and downloaded through a network and will be stored in a local storage medium, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state drive, etc.; optionally, the storage medium can also include a combination of the above-mentioned types of memory. It can be understood that a computer, a processor, a microprocessor controller or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor or hardware, the method shown in the above embodiment is implemented.

[0217] Although the embodiments of the present application have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations shall fall within the scope defined by the appended claims.

Claims

1. A method for detecting photovoltaic array faults, characterized in that: The photovoltaic array includes at least one photovoltaic component, and the photovoltaic array is connected to a signal transmission system and a filtering system respectively, the signal transmission system includes a first signal transmission device connected to one end of the photovoltaic array, and a second signal transmission device connected to the other end of the photovoltaic array; the method includes: Acquire a photovoltaic array state information library, wherein the photovoltaic array state information library includes a state reflection signal waveform diagram of each photovoltaic component in each state; Utilize the first signal transmission device and the second signal transmission device in the signal transmission system to send step signals to the photovoltaic array respectively; Acquire a state reflection signal of each photovoltaic component in the photovoltaic array based on the step signal; Sending the state reflection signal of each photovoltaic component to the filtering system for filtering processing to obtain a target state reflection signal waveform diagram of each photovoltaic component; Based on the photovoltaic array state information library and the target state reflection signal waveform of each photovoltaic component, the photovoltaic array is fault detected to obtain the fault detection result of the photovoltaic array, including: matching the state reflection signal of each photovoltaic component in each state in the photovoltaic array with the photovoltaic array state information library to obtain the fault detection result of the photovoltaic array.

2. The method according to claim 1, characterized in that Obtain the PV array status information library, including: Using the signal transmission system to send the step signal to the photovoltaic array, and acquiring at least one state reflection signal of each photovoltaic component in the photovoltaic array based on the step signal; Sending each state reflection signal of each photovoltaic component to the filtering system for filtering processing to obtain at least one state reflection signal waveform diagram of each photovoltaic component; The photovoltaic array state information library is established based on each state reflection signal waveform diagram of each photovoltaic component.

3. The method according to claim 2, characterized in that After using the signal transmission system to send a step signal to the photovoltaic array, and before acquiring a state reflection signal of each photovoltaic component in the photovoltaic array based on the step signal, the method further includes: When the first signal transmission device does not receive the state reflection signal within a preset unit time, sending a step signal to send a request instruction to the second signal transmission device; determining whether the first signal transmission device receives a response instruction sent by the second signal transmission device; When the first signal transmission device does not receive the response instruction, it is determined that the second signal transmission device fails; When the first signal transmission device receives the response instruction and the first signal transmission device does not receive the status reflection signal within the preset unit time, it is determined that the second signal transmission device fails.

4. The method according to claim 1, characterized in that: The filtering system includes a first high-pass filter and a second high-pass filter; the state reflection signal of each photovoltaic component is sent to the filtering system for filtering processing to obtain a target state reflection signal waveform of each photovoltaic component, including: Sending the state reflection signal of each photovoltaic module to the first high-pass filter for filtering to obtain a first state reflection signal waveform diagram and a first signal-to-noise ratio value; Sending the state reflection signal of each photovoltaic module filtered by the first high-pass filter to the second high-pass filter for filtering to obtain a second state reflection signal waveform diagram and a second signal-to-noise ratio value; Comparing the first signal-to-noise ratio value with a preset signal-to-noise ratio threshold, and comparing the second state reflection signal waveform with the first state reflection signal waveform to obtain a difference value; When the first signal-to-noise ratio value is less than the preset signal-to-noise ratio threshold, and the difference value is less than the preset difference threshold, respectively adjust the signal cutoff frequencies of the first high-pass filter and the second high-pass filter, and based on the adjusted first high-pass filter and the second high-pass filter, process the state reflection signal of each of the photovoltaic components until the second signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, then stop adjusting, and obtain the target state reflection signal waveform diagram; When the first signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, and the difference value is less than the preset difference threshold, the second state reflection signal waveform diagram is used as the target state reflection signal waveform diagram.

5. The method according to claim 4, characterized in that After comparing the second state reflection signal waveform diagram with the first state reflection signal waveform diagram to obtain a difference value, the method further includes: When the first signal-to-noise ratio value is less than the preset signal-to-noise ratio threshold, and the difference value is greater than or equal to the preset difference threshold, determining that the first high-pass filter and the second high-pass filter are faulty; When the first signal-to-noise ratio value is greater than or equal to the preset signal-to-noise ratio threshold, and the difference value is greater than the preset difference threshold, it is determined that the first high-pass filter and the second high-pass filter fail.

6. The method according to claim 3, characterized in that The photovoltaic array state information library is established based on each state reflection signal waveform diagram of each photovoltaic component, including: Based on each state reflection signal waveform diagram, obtaining a first distance between each photovoltaic component and the first signal transmission device and a second distance between each photovoltaic component and the second signal transmission device; Based on each state reflection signal waveform diagram, an initial three-dimensional image of each photovoltaic module is obtained by processing with a time domain reflection imaging method; Determine a target position and a target three-dimensional image of each photovoltaic component based on the first distance, the second distance and the initial three-dimensional image of each photovoltaic component; The photovoltaic array state information library is established based on each state reflection signal waveform diagram of each photovoltaic component and the target three-dimensional image.

7. The method according to claim 6, characterized in that Based on the photovoltaic array state information library and the target state reflection signal waveform diagram of each photovoltaic component, the photovoltaic array is subjected to fault detection to obtain a fault detection result of the photovoltaic array, including: Based on the target position of each photovoltaic component, determining the serial number of each photovoltaic component in the photovoltaic array state information library; Based on the photovoltaic array state information library, the number of each photovoltaic component and the target state reflection signal waveform diagram, each photovoltaic component is subjected to fault detection to obtain a fault detection result of each photovoltaic component, including: matching the number of each photovoltaic component and the target state reflection signal waveform diagram with the number and state reflection signal waveform diagram of the photovoltaic component included in the photovoltaic array state information library, and then determining the current state of the corresponding photovoltaic component according to the matching result; Based on the fault detection result of each of the photovoltaic components, the fault detection result of the photovoltaic array is determined.

8. A photovoltaic array fault detection device, characterized in that: The photovoltaic array includes at least one photovoltaic component, and the photovoltaic array is connected to a signal transmission system and a filtering system respectively, the signal transmission system includes a first signal transmission device connected to one end of the photovoltaic array, and a second signal transmission device connected to the other end of the photovoltaic array; the device includes: A first acquisition module is used to acquire a photovoltaic array state information library, wherein the photovoltaic array state information library includes a state reflection signal waveform diagram of each photovoltaic component in each state; A sending module, used for sending a step signal to the photovoltaic array by using the first signal transmission device and the second signal transmission device in the signal transmission system respectively; A second acquisition module, configured to acquire a state reflection signal of each photovoltaic component in the photovoltaic array based on the step signal; A filtering processing module, used for sending the state reflection signal of each photovoltaic component to the filtering system for filtering processing to obtain a target state reflection signal waveform of each photovoltaic component; The detection module performs fault detection on the photovoltaic array based on the photovoltaic array state information library and the target state reflection signal waveform of each photovoltaic component to obtain the fault detection result of the photovoltaic array, including: matching the state reflection signal of each photovoltaic component in each state in the photovoltaic array with the photovoltaic array state information library to obtain the fault detection result of the photovoltaic array.

9. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the photovoltaic array fault detection method according to any one of claims 1 to 7 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the photovoltaic array fault detection method according to any one of claims 1 to 7.

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