Photovoltaic module subfissure detection system and method

Abstract

The invention relates to the field of photovoltaic technology, and discloses a photovoltaic module subfissure detection system and method.The system comprises a photovoltaic module, energy storage equipment electrically connected with the photovoltaic module, a remote control platform in communication connection with the energy storage equipment and an inverter electrically connected with the energy storage equipment, and the inverter is used for being electrically connected with a power grid. The problems that in the prior art, equipment cost is high, operation is relatively complex, and time and labor are wasted are solved.

Description

Technical Field

[0001] The invention relates to the field of photovoltaic technology, and in particular to a photovoltaic component hidden crack detection system and method. Background Art

[0002] Hidden cracks (micro cracks) in photovoltaic modules refer to fine cracks that are difficult to detect with the naked eye. These cracks may occur during production, transportation, installation or use. Hidden cracks will reduce the performance of photovoltaic modules and may cause long-term reliability problems. Therefore, timely detection and treatment of hidden cracks are essential to ensure the stable operation of photovoltaic systems. Electroluminescence (EL) is commonly used on-site in photovoltaic power stations to detect hidden cracks in modules. However, this method currently requires special equipment, and the equipment cost is high, the operation is relatively complex, time-consuming and labor-intensive. It is extremely difficult to detect hidden cracks in large photovoltaic power stations. Summary of the invention

[0003] In order to overcome the deficiencies of the prior art, the present invention provides a photovoltaic module hidden crack detection system and method, which solves the problems of high equipment cost, relatively complex operation, time-consuming and labor-intensive, etc. in the prior art.

[0004] The technical solution adopted by the present invention to solve the above problems is:

[0005] A photovoltaic component hidden crack detection system comprises a photovoltaic component, an energy storage device electrically connected to the photovoltaic component, a remote control platform communicatively connected to the energy storage device, and an inverter electrically connected to the energy storage device, wherein the inverter is used to be electrically connected to a power grid.

[0006] As a preferred technical solution, the energy storage device includes an input terminal and an output terminal. The input terminal is used to be electrically connected to the photovoltaic module, and the output terminal is used to be electrically connected to other energy storage devices.

[0007] As a preferred technical solution, the input terminal includes an input terminal positive pole In+ and an input terminal negative pole In-, and the output terminal includes an output terminal positive pole Out+ and an output terminal negative pole Out-.

[0008] As a preferred technical solution, the energy storage device includes a DC-DC circuit, an energy storage battery, and an energy storage controller, and the DC-DC circuit is electrically connected to the energy storage battery and the energy storage controller respectively.

[0009] As a preferred technical solution, it includes a current sampling circuit, which is electrically connected to the DC-DC circuit and the energy storage controller respectively.

[0010] As a preferred technical solution, the current sampling circuit is electrically connected to the positive electrode In+ of the input terminal.

[0011] As a preferred technical solution, it includes a voltage sampling circuit, and the voltage sampling circuit is electrically connected to the DC-DC circuit and the energy storage controller respectively.

[0012] As a preferred technical solution, the voltage sampling circuit is electrically connected to the positive input terminal In+ and the negative input terminal In- respectively.

[0013] A photovoltaic component hidden crack detection method uses the photovoltaic component hidden crack detection system to perform hidden crack detection on the photovoltaic component.

[0014] As a preferred technical solution, the following steps are included:

[0015] S1, control the inverter to stop working through the control platform, so that the inverter no longer outputs electric energy to the grid;

[0016] S2, the energy storage device discharges to the PV module under test;

[0017] S3, taking photos of the photovoltaic module to be tested;

[0018] S4, control the energy storage device through the control platform to stop outputting power to the photovoltaic module, and then perform hidden crack analysis based on infrared photos.

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

[0020] (1) No need for workers to go to the site to power on each PV module one by one, which improves efficiency;

[0021] (2) Not limited by scale, all photovoltaic modules to be tested in the photovoltaic station can be tested simultaneously;

[0022] (3) No need for professional EL testing equipment, reducing testing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of energy storage device discharging to photovoltaic panels;

[0024] Figure 2 This is a schematic diagram of the discharge of photovoltaic string energy storage equipment;

[0025] Figure 3 It is a schematic diagram of the circuit structure of the energy storage device;

[0026] Figure 4 It is the schematic diagram of the discharge control loop;

[0027] Figure 5 This is the workflow diagram for hidden crack detection. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0029] Example 1

[0030] like Figures 1 to 5 As shown, a photovoltaic module hidden crack detection system includes a control platform, an inverter electrically connected to the control platform, and an energy storage device electrically connected to the inverter. The control platform is electrically connected to the energy storage device, and the energy storage device is used to be electrically connected to the photovoltaic module.

[0031] The present invention does not require any specialized equipment, but uses energy storage equipment to provide electrical energy, and uses the EL principle to detect hidden cracks in photovoltaic modules, and can simultaneously detect all photovoltaic modules in a photovoltaic power station. It can greatly improve the efficiency of hidden crack detection and is applicable to large photovoltaic power stations.

[0032] As a preferred technical solution, the energy storage device includes an input terminal and an output terminal. The input terminal is used to be electrically connected to the photovoltaic module, and the output terminal is used to be electrically connected to other energy storage devices.

[0033] As a preferred technical solution, the input terminal includes an input terminal positive pole In+ and an input terminal negative pole In-, and the output terminal includes an output terminal positive pole Out+ and an output terminal negative pole Out-.

[0034] The energy storage device is electrically connected to the photovoltaic module and other energy storage devices through input terminals and output terminals.

[0035] As a preferred technical solution, the energy storage device includes a DC-DC circuit, an energy storage battery, and an energy storage controller, and the DC-DC circuit is electrically connected to the energy storage battery and the energy storage controller respectively.

[0036] This facilitates charge and discharge control.

[0037] As a preferred technical solution, it includes a current sampling circuit, which is electrically connected to the DC-DC circuit and the energy storage controller respectively.

[0038] As a preferred technical solution, the current sampling circuit is electrically connected to the positive electrode In+ of the input terminal.

[0039] Its function is: the current sampling result is used for negative feedback control.

[0040] As a preferred technical solution, it includes a voltage sampling circuit, and the voltage sampling circuit is electrically connected to the DC-DC circuit and the energy storage controller respectively.

[0041] As a preferred technical solution, the voltage sampling circuit is electrically connected to the positive input terminal In+ and the negative input terminal In- respectively.

[0042] Its function is: the voltage sampling result is used for negative feedback control.

[0043] A photovoltaic component hidden crack detection method uses the photovoltaic component hidden crack detection system to perform hidden crack detection on the photovoltaic component.

[0044] As a preferred technical solution, the following steps are included:

[0045] S1, control the inverter to stop working through the control platform, so that the inverter no longer outputs electric energy to the grid;

[0046] S2, the energy storage device discharges to the PV module under test;

[0047] S3, taking photos of the photovoltaic module to be tested;

[0048] S4, control the energy storage device through the control platform to stop outputting power to the photovoltaic module, and then perform hidden crack analysis based on infrared photos.

[0049] The present invention has the following technical effects:

[0050] (1) No need for workers to go to the site to power on each PV module one by one, which improves efficiency;

[0051] (2) Not limited by scale, all photovoltaic modules to be tested in the photovoltaic station can be tested simultaneously;

[0052] (3) No need for professional EL testing equipment, reducing testing costs.

[0053] Example 2

[0054] like Figures 1 to 5 As shown, based on Example 1, this example provides a more detailed implementation method.

[0055] The present invention proposes a method for detecting hidden cracks based on photovoltaic module-level energy storage equipment. It does not require any specialized equipment, uses energy storage equipment to provide electrical energy, and uses the EL principle to detect hidden cracks in photovoltaic modules. It can detect all photovoltaic modules in a photovoltaic power station at the same time. It can greatly improve the efficiency of hidden crack detection and is applicable to large photovoltaic power stations. Figure 1 In the embodiment, the photovoltaic module includes a photovoltaic assembly (including photovoltaic cells, etc.) and an energy storage device. In this embodiment, the width of the hidden crack is in the range of (0,5) mm; however, the inventive concept of the present invention is not limited to this range.

[0056] The method involves photovoltaic components, component-level energy storage devices, inverters, and a control platform.

[0057] The energy storage device is directly connected to 1-3 photovoltaic panels.

[0058] The energy storage device has a built-in DC-DC circuit and an energy storage battery, and can discharge energy externally through the DC-DC circuit.

[0059] The energy storage device has a pair of input terminals In+, In- and output terminals Out+, Out-. The input terminals are connected to the output terminals of the photovoltaic modules, and the output terminals are connected in series to the output terminals of other energy storage devices.

[0060] The remote control platform can communicate remotely with the inverter, and the remote control platform can communicate remotely with the energy storage device.

[0061] like Figure 5 As shown in the figure, the workflow of hidden split detection is:

[0062] 1) At night, the inverter is controlled to stop working through the remote control platform and no longer outputs power to the grid;

[0063] 2) The remote controlled energy storage device discharges to the PV module under test through the In+ and In- terminals through its built-in DC-DC circuit, and records the output voltage as Vref and the output current as Iref. The discharge direction is In+ outflow and In-inflow.

[0064] The discharge control method of the energy storage device to the photovoltaic module is a software cascade control implemented by the energy storage controller: the outer loop is a voltage negative feedback closed-loop control, the outer loop voltage controls the voltage V(In+_In-) at both ends of In+ and In-, the reference value is the default value set by the energy storage controller software or the remote control platform setting value, and the feedback comes from the voltage sampling circuit; the inner loop is a current negative feedback closed-loop control, the inner loop controls the discharge current I(In+_In-), the current reference value comes from the output of the voltage control loop, the feedback comes from the current sampling circuit, and the output of the current control loop acts on the DC-DC circuit. It is worth noting that the voltage control algorithm and the current control algorithm are integrated in the energy storage controller and can be implemented using existing technologies, so their specific contents will not be repeated.

[0065] 3) Use a drone carrying an infrared camera to take photos and record the photovoltaic components to be tested.

[0066] 4) Control the energy storage device to stop outputting power to the photovoltaic module. After the energy storage device stops outputting power to the photovoltaic module, perform hidden crack analysis based on infrared photos (this can be achieved through existing technology, so its working principle and working process will not be described in detail here).

[0067] The present invention has the following technical effects:

[0068] (1) No need for workers to go to the site to power on each PV module one by one, which improves efficiency;

[0069] (2) Not limited by scale, all photovoltaic modules to be tested in the photovoltaic station can be tested simultaneously;

[0070] (3) No need for professional EL testing equipment, reducing testing costs.

[0071] As described above, the present invention can be preferably implemented.

[0072] All features disclosed in all embodiments in this specification, or steps in all methods or processes implicitly disclosed, except for mutually exclusive features and / or steps, can be combined and / or expanded or replaced in any manner.

[0073] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. According to the technical essence of the present invention, within the spirit and principles of the present invention, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the present invention.

Claims

1. A photovoltaic module hidden crack detection system, characterized in that: Photovoltaic components, energy storage devices electrically connected to the photovoltaic components, a remote control platform communicatively connected to the energy storage devices, and an inverter electrically connected to the energy storage devices, wherein the inverter is used to be electrically connected to a power grid.

2. A photovoltaic module hidden crack detection system according to claim 1, characterized in that: The energy storage device includes an input terminal and an output terminal. The input terminal is used to be electrically connected to the photovoltaic module, and the output terminal is used to be electrically connected to other energy storage devices.

3. A photovoltaic module hidden crack detection system according to claim 2, characterized in that: The input terminal includes an input terminal positive electrode In+ and an input terminal negative electrode In-, and the output terminal includes an output terminal positive electrode Out+ and an output terminal negative electrode Out-.

4. A photovoltaic module hidden crack detection system according to claim 3, characterized in that: The energy storage device includes a DC-DC circuit, an energy storage battery, and an energy storage controller. The DC-DC circuit is electrically connected to the energy storage battery and the energy storage controller respectively.

5. A photovoltaic module hidden crack detection system according to claim 4, characterized in that: It includes a current sampling circuit, which is electrically connected to a DC-DC circuit and an energy storage controller respectively.

6. A photovoltaic module hidden crack detection system according to claim 5, characterized in that: The current sampling circuit is electrically connected to the positive electrode In+ of the input terminal.

7. A photovoltaic module hidden crack detection system according to claim 5 or 6, characterized in that: It includes a voltage sampling circuit, which is electrically connected to the DC-DC circuit and the energy storage controller respectively.

8. A photovoltaic module hidden crack detection system according to claim 7, characterized in that: The voltage sampling circuit is electrically connected to the positive electrode In+ of the input terminal and the negative electrode In- of the input terminal respectively.

9. A method for detecting hidden cracks in photovoltaic modules, characterized in that: A photovoltaic module hidden crack detection system as described in any one of claims 1 to 8 is used to detect hidden cracks in photovoltaic modules.

10. A photovoltaic module hidden crack detection method according to claim 9, characterized in that: The following steps are involved: S1, control the inverter to stop working through the control platform, so that the inverter no longer outputs electric energy to the grid; S2, the energy storage device discharges to the PV module under test; S3, taking photos of the photovoltaic module to be tested; S4, control the energy storage device through the control platform to stop outputting power to the photovoltaic module, and then perform hidden crack analysis based on infrared photos.

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