A Photovoltaic Glazed Glass PID Testing Device and Method

Abstract

The present invention discloses a PID testing device and method for glazed photovoltaic glass. In the testing device, one end of a metal electrode is disposed on the glazed side surface of the glazed glass, and an EVA film is coated on the glazed side surface of the glazed glass and on the side surface of the metal electrode facing away from the glazed surface of the glazed glass. Then, a ultra-clear glass is laminated on the EVA film. The glazed glass, the metal electrode and the ultra-clear glass are bonded together by the EVA film to form a component under test. The other end of the metal electrode extends outwards from the component under test, and the periphery of the component under test is wrapped by a metal foil, with the metal foil not contacting the metal electrode. Then, by connecting the metal foil to the negative pole of a power supply and the other end of the metal electrode to the positive pole of the power supply, a loop is formed for PID testing. Thus, the PID testing device for glazed photovoltaic glass can still perform PID testing on photovoltaic modules without placing battery cells, which not only reduces the sample preparation cost but also reduces the PID testing cycle.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of solar photovoltaics, and in particular to a PID test device and method for photovoltaic enameled glass. Background Art

[0002] With the continuous improvement of the power of photovoltaic modules and the improvement of the supporting facilities of photovoltaic inverters, the grid-connected system voltage is getting higher and higher, and the commonly used ones are 1000V and 1500V. Generally, the aluminum frames of components are required to be grounded, so a high voltage of 1000V - 1500V is formed between the battery cells and the aluminum frames. Generally speaking, during the lamination process of double-sided double-glass module packaging, the structure is 5 layers. The battery cells are in the middle of the EVA, and the high-transmittance glass and enameled glass are on the outermost layer. During the lamination process, the EVA forms a transparent and electrically insulating substance. However, no plastic material can be 100% insulating and has a certain degree of conductivity. Especially in a humid environment, there will be leakage current flowing through the battery cells, packaging materials, glass, backplane, and aluminum frame. If a high voltage is formed between the internal circuit and the aluminum frame, the leakage current will reach the microampere or milliampere level, which will form the Potential Induced Degradation (PID effect).

[0003] The PID effect deteriorates the surface passivation effect of the battery and forms a leakage current loop, resulting in a decrease in the fill factor, open-circuit voltage, and short-circuit current, making the component performance lower than the design standard. In the presence of voltage and current environments, the movement of electrons occurs. With the participation of alkali metal ions such as sodium and calcium in the glass, Ti3 + forms, causing the tetragonal lattice of white TiO2 to be disordered, resulting in a decrease in the energy required for electrons in the valence band to transition to the conduction band, a narrowing of the band gap, and enabling the original white TiO2 to be excited by photons with smaller energy, thereby absorbing some visible light with lower energy, and the enameled glass forms color change.

[0004] The usual PID test does not directly detect the glazed glass, but the component. The test conditions are generally to apply a voltage of -1000 / -1500V to the component under the environmental conditions of a temperature of 85°C and a relative humidity of 85%, and continuously test for 96 hours or 192 hours. If the attenuation ratio of the component power before and after the PID test is less than 5%, and there is no change in appearance, the component is considered to pass the PID test. Since the component manufacturing process and packaging materials also have a great influence on the PID effect of the component, the PID test result of the component cannot directly indicate whether the glazed glass has the ability to resist the PID effect and whether the appearance color is normal. Moreover, the PID test cycle of the component is long and the process is complex. At the same time, it cannot timely and effectively judge whether the glazed glass resists PID, and cannot timely feedback the quality of the glazed glass's resistance to PID. Therefore, the PID test method at the component material end has become an effective method to solve the above problems. Summary of the Invention

[0005] The present invention provides a PID test device and method for photovoltaic glazed glass, so as to realize the PID test of photovoltaic components without placing solar cells, which not only reduces the sample preparation cost, but also reduces the PID test cycle.

[0006] To achieve the above object, an embodiment of one aspect of the present invention provides a PID test device for photovoltaic glazed glass, including:

[0007] Glazed glass, metal electrode, ultra-white glass, EVA film, metal foil and power supply; wherein, one end of the metal electrode is located on the glazed side surface of the glazed glass; the EVA film is located on the glazed side surface of the glazed glass and on the side surface of the metal electrode facing away from the glazed side surface of the glazed glass; the ultra-white glass is located on the side surface of the EVA film facing away from the glazed side surface of the glazed glass; the EVA film is used to bond the glazed glass, one end of the metal electrode and the ultra-white glass to form a component to be tested; the metal foil wraps around the periphery of the component to be tested, the metal foil is connected to the negative pole of the power supply, and the other end of the metal electrode extends outwards from the component to be tested and is connected to the positive pole of the power supply; wherein, the metal foil does not contact the metal electrode.

[0008] According to an embodiment of the present invention, an insulating layer is provided between the metal foil and the metal electrode, or the metal foil and the metal electrode are spaced 1-5 mm apart. To avoid direct connection between the positive and negative poles, causing a short circuit.

[0009] According to an embodiment of the present invention, the metal foil is aluminum foil or copper foil.

[0010] According to an embodiment of the present invention, the power supply is a DC voltage power supply, and the voltage range is 1KV-1.5KV.

[0011] According to an embodiment of the present invention, the metal electrode is a tinned metal strip. Directly using the tinned metal strip used in photovoltaic modules, taking materials locally, is relatively convenient.

[0012] To achieve the above object, another embodiment of the present invention provides a method for testing the PID of photovoltaic enameled glass, which is implemented based on the above-mentioned photovoltaic enameled glass PID testing device, and includes the following steps:

[0013] Step 1: Place the photovoltaic enameled glass PID testing device in a testing environment and connect the testing wires. Among them, control the environmental temperature to be 0 - 100 °C and the relative humidity to be 0 - 100% RH;

[0014] Step 2: Turn on the power supply, and under the action of a high voltage, make the metal electrode generate corona discharge, and the ion flow acts on the surface of the enameled glass;

[0015] Step 3: Continuously perform ion radiation on the enameled glass, and observe in real time whether the appearance of the enameled glass changes color;

[0016] Step 4: Record the color change situation of the appearance of the enameled glass, and analyze the PID resistance performance of the enameled glass.

[0017] According to an embodiment of the present invention, the environmental temperature in Step 1 is 85 °C and the relative humidity is 85% RH. Being close to the working environment of a real photovoltaic module is conducive to obtaining real test data.

[0018] According to an embodiment of the present invention, the power supply in Step 2 is a DC voltage power supply, and the voltage is 1.5 KV. The power supply voltage of 1.5 KV is the same as the commonly used voltage in the grid-connected system, and the test environment is closer to the real working environment.

[0019] According to an embodiment of the present invention, the time for continuously performing ion radiation on the enameled glass in Step 3 is a multiple of 96 hours, and the interval time for observing whether the appearance of the enameled glass changes color is 24 hours. Among them, the time for continuously performing ion radiation is 96 hours or 192 hours. If the enameled glass changes color, the basic time is less than this duration. If the time is too short, it is possible that the color change of the enameled glass cannot be observed. If the time is too long, the time cost will increase.

[0020] According to an embodiment of the present invention, Step 4 includes: when the appearance of the enameled glass changes color, the enameled glass does not have PID resistance performance; when the appearance of the enameled glass does not change color significantly, the enameled glass has PID resistance performance.

[0021] The PID testing device and method for photovoltaic enamelled glass according to the embodiments of the present invention. In the testing device, one end of a metal electrode is disposed on the enamelled side surface of the enamelled glass, and an EVA film is coated on the enamelled side surface of the enamelled glass and on the side surface of the metal electrode facing away from the enamelled glass. Then, a ultra-clear glass is laminated on the EVA film. The enamelled glass, the metal electrode and the ultra-clear glass are bonded together by the EVA film to form a component under test. One end of the metal electrode extends outwards from the component under test, and the periphery of the component under test is wrapped by a metal foil which does not contact the metal electrode. Then, by connecting the metal foil to the negative pole of a power supply and the other end of the metal electrode to the positive pole of the power supply, a loop is formed for PID testing. When it is observed that the enamelled glass changes color, it indicates that the enamelled glass does not have PID resistance performance. When it is observed that the enamelled glass hardly changes color, it indicates that the enamelled glass has PID resistance performance. Thus, the PID testing device for photovoltaic enamelled glass can still perform PID testing on photovoltaic modules without placing solar cells, which not only reduces the sample preparation cost but also reduces the PID testing cycle.

[0022] In addition, the PID testing device for photovoltaic enamelled glass does not require additional pre-attenuation processing of the component power, power testing of the component after PID testing, and withstand voltage insulation wet leakage testing, thus reducing the PID testing cycle of the entire photovoltaic module. And in the PID testing device for photovoltaic enamelled glass, there is no need to place solar cells, and the usage amounts of the EVA film and the glass are small, the sample preparation time is short, it does not affect the normal production operation of the production line, and does not additionally increase the labor cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of the PID testing device for photovoltaic enamelled glass according to the embodiments of the present invention;

[0024] Figure 2 is Figure 1 a sectional view taken along the AA' direction in

[0025] Figure 3 is a schematic structural diagram of the PID testing device for photovoltaic enamelled glass according to an embodiment of the present invention;

[0026] Figure 4 is a schematic structural diagram of the PID testing device for photovoltaic enamelled glass according to another embodiment of the present invention;

[0027] Figure 5 is a flowchart of the PID testing method for photovoltaic enamelled glass according to the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only for explaining the present invention, rather than limiting the present invention. In addition, it should be noted that for the sake of description, only the parts related to the present invention rather than all the structures are shown in the drawings.

[0029] In the prior art, components are usually tested. The components include five layers, which makes the entire detection and test cycle relatively long (from the power pre-decay treatment of the components to the power test of the components after PID test, and then to the withstand voltage theater wet leakage test), and the sample preparation cost is relatively high (the same as that of normal components), which affects the production capacity and also increases the labor cost.

[0030] To solve the above technical problems, an embodiment of the present invention provides a PID test device and method for photovoltaic enameled glass, so as to realize PID testing of photovoltaic modules without placing battery wafers, which not only reduces the sample preparation cost but also reduces the PID test cycle.

[0031] First, the PID test device for photovoltaic enameled glass proposed by the embodiment of the present invention will be introduced below.

[0032] Figure 1 FIG. is a schematic structural diagram of the PID test device for photovoltaic enameled glass proposed by the embodiment of the present invention. Figure 2 is Figure 1 a sectional view taken along the AA' direction in FIG. As Figure 1 and Figure 2 shown, the PID test device 100 for photovoltaic enameled glass includes:

[0033] Enameled glass 101, metal electrode 102, ultra-white glass 103, EVA film 104, metal foil 105, and power supply 106; wherein, one end of the metal electrode 102 is located on the enameled side surface of the enameled glass 101; the EVA film 104 is located on the enameled side surface of the enameled glass 101 and on the side surface of the metal electrode 102 facing away from the enameled side surface of the enameled glass 101; the ultra-white glass 103 is located on the side surface of the EVA film 104 facing away from the enameled side surface of the enameled glass 101; the EVA film 104 is used to bond the enameled glass 101, one end of the metal electrode 102, and the ultra-white glass 103 to form a component to be tested 107; the metal foil 105 wraps around the periphery of the component to be tested 107, the metal foil 105 is connected to the negative electrode of the power supply 106, and the other end of the metal electrode 102 extends outwards from the component to be tested 107 and is connected to the positive electrode of the power supply 106; wherein, the metal foil 105 does not contact the metal electrode 102.

[0034] It should be noted that the size of the enameled glass 101 can be 300mm * 300mm, or it can be other sizes. The present invention does not make specific limitations in this regard. In addition, the thickness of the metal electrode 102 can be 0.25mm, the width is 6mm, and the length is determined according to the size of the enameled glass 101. If the size of the enameled glass 101 is larger, the length can be longer; if the size of the enameled glass 101 is smaller, the length can be smaller.

[0035] Among them, after the enameled glass 101, the metal electrode 102, the EVA film 104 and the ultra-clear glass 103 are laminated, the component to be measured 107 is formed. The metal foil 105 wraps around the periphery of the component to be measured 107. Among them, the metal foil 105 is isolated from the metal electrode 102 to prevent the positive and negative poles of the power supply 106 from being connected together to cause a short circuit. It can be understood that the ultra-clear glass 103 refers to glass with a light transmittance greater than 95%. The tester can observe the color change of the enameled glass 101 through the ultra-clear glass 103. The EVA film 104 is the abbreviation of Polyethylenevinylacetate, a copolymer of polyethylene and polyvinyl acetate.

[0036] After connecting the power supply 106 as described above for the PID test device 100 of the photovoltaic enameled glass, the PID test device 100 of the photovoltaic enameled glass can be placed in a test environment. Among them, the control environment temperature is 85°C, and the relative humidity is 85%RH; the power supply 106 is turned on, and corona discharge is generated on the metal electrode under the action of a high voltage (1.5KV), and the ion flow acts on the surface of the enameled glass; then the enameled glass is continuously subjected to ion radiation for 96 hours, and the appearance of the enameled glass is observed in real time (observed once every 24 hours), and then the color change of the appearance of the enameled glass is recorded, and the anti-PID performance of the enameled glass is analyzed. When the appearance of the enameled glass 101 changes color, the enameled glass 101 does not have anti-PID performance; when the appearance of the enameled glass 101 does not change color significantly, the enameled glass 101 has anti-PID performance.

[0037] Based on this, the PID test can be directly carried out on the enameled glass 101 and its ability to resist PID can be judged, without having to make the battery cells into components and then carry out the PID test, effectively saving the detection time and cost, and at the same time being conducive to the optimization and improvement of the enameled glass 101.

[0038] According to an embodiment of the present invention, as Figure 1 、 Figure 3 and Figure 4 shown, an insulating layer 108 is provided between the metal foil 105 and the metal electrode 102 (as Figure 3 and Figure 4as shown), or, there is a 1 - 5 mm gap (such as Figure 1 as shown) between the metal foil 105 and the metal electrode 102. In this way, the metal foil 105 and the metal electrode 102 are isolated to prevent the positive and negative poles of the power supply 106 from being connected together to cause a short circuit. Among them, the insulating layer 108 can be glass, that is to say, when manufacturing the component under test 107, the glazed glass 101 and the ultra-white glass 103 can protrude outward by a part such as Figure 3 as shown, and can protrude 1 - 2 mm.

[0039] According to an embodiment of the present invention, the metal foil 105 is an aluminum foil or a copper foil.

[0040] According to an embodiment of the present invention, the power supply 106 is a DC voltage power supply, and the voltage range is 1 KV - 1.5 KV.

[0041] According to an embodiment of the present invention, the metal electrode 102 is a metal tinned tape. Among them, the base material of the metal tinned tape can be copper or aluminum, or other conductive metals, and the present invention does not make specific limitations on this. The metal tinned tape can use local materials, which is convenient for manufacturing the component under test 107.

[0042] Next, the PID test method for photovoltaic glazed glass proposed by the embodiment of the present invention will be introduced.

[0043] Figure 5 is a flowchart of the PID test method for photovoltaic glazed glass proposed by the embodiment of the present invention. This method is implemented based on the photovoltaic glazed glass PID test device 100 as described above. (It should be noted that the photovoltaic glazed glass PID test device 100 has been introduced in detail in the previous example and will not be repeated here.) As Figure 5 shown, this method includes the following steps:

[0044] Step 1: Place the photovoltaic glazed glass PID test device in the test environment and connect the test wires. Among them, control the environmental temperature to be 0 - 100 °C and the relative humidity to be 0 - 100% RH;

[0045] According to an embodiment of the present invention, the environmental temperature in Step 1 is 85 °C and the relative humidity is 85% RH. Being close to the working environment of a real photovoltaic module is beneficial to obtaining real test data.

[0046] Step 2: Turn on the power supply, and under the action of high voltage, make the metal electrode generate corona discharge, and the ion flow acts on the surface of the glazed glass;

[0047] According to an embodiment of the present invention, the power supply in the second step is a DC voltage power supply with a voltage of 1.5 KV. The power supply voltage of 1.5 KV is the same as the common voltage in the grid-connected system, making the test environment closer to the actual working environment. Alternatively, the power supply voltage can also be 1 KV. The specific voltage used is tested according to the voltage of the photovoltaic module in the grid connection in actual situations.

[0048] Step 3: Continuously perform ion radiation on the enameled glass, and observe in real time whether the appearance of the enameled glass changes color;

[0049] According to an embodiment of the present invention, the time for continuously performing ion radiation on the enameled glass in the third step is a multiple of 96 hours, and the interval time for observing whether the appearance of the enameled glass changes color is 24 hours. Among them, the time for continuously performing ion radiation on the enameled glass in the third step is 96 hours or 192 hours. If the enameled glass changes color, the basic time is less than this duration. If the time is too short, it may be impossible to observe the color change of the enameled glass. If the time is too long, the time cost will increase.

[0050] Step 4: Record the color change situation of the appearance of the enameled glass, and analyze the anti-PID performance of the enameled glass.

[0051] According to an embodiment of the present invention, the fourth step includes: when the appearance of the enameled glass changes color, the enameled glass does not have anti-PID performance; when the appearance of the enameled glass does not change color significantly, the enameled glass has anti-PID performance. It should be noted that observing whether the enameled glass changes color means that if the enameled glass is originally white, then the appearance becomes non-white. For example, if the white color becomes slightly lighter or turns yellow, etc., all belong to the color change of the appearance of the enameled glass. That is, as long as the color of the appearance of the enameled glass is different from its own color before the test, the appearance of the enameled glass has changed color.

[0052] In summary, according to the photovoltaic enameled glass PID testing device and method proposed in the embodiments of the present invention, in the testing device, one end of the metal electrode is disposed on the enameled side surface of the enameled glass, and the EVA film is coated on the enameled side surface of the enameled glass and on the side surface of the metal electrode away from the enameled side surface of the enameled glass. Then, the ultra-white glass is laminated on the EVA film, and the enameled glass, the metal electrode, and the ultra-white glass are bonded together by the EVA film to form a component under test. Among them, the other end of the metal electrode extends outwards from the component under test, and the periphery of the component under test is wrapped by a metal foil, and the metal foil does not contact the metal electrode. Then, by connecting the metal foil to the negative pole of the power supply and the other end of the metal electrode to the positive pole of the power supply, a loop is formed for PID testing. When it is observed that the enameled glass changes color, it indicates that the enameled glass does not have PID resistance. When it is observed that the enameled glass hardly changes color, it indicates that the enameled glass has PID resistance. Thus, the photovoltaic enameled glass PID testing device can still perform PID testing on photovoltaic modules without placing solar cells, which not only reduces the sample preparation cost but also reduces the PID testing cycle.

[0053] In addition, the photovoltaic enameled glass PID testing device does not require additional power pre-attenuation treatment of the test component, power testing of the component after PID testing, and withstand voltage insulation wet leakage testing, thereby reducing the PID testing cycle of the entire photovoltaic module. And in the photovoltaic enameled glass PID testing device, there is no need to place solar cells, and the usage amounts of the EVA film and the glass are small, the sample preparation time is short, it does not affect the normal production operation of the production line, and it does not additionally increase the labor cost.

[0054] Note that the above is only the preferred embodiment of the present invention and the applied technical principle. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, it can also include more other equivalent embodiments, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A PID test device for photovoltaic enamelled glass, characterized in that, Including: Glazed glass, metal electrode, ultra-clear glass, EVA film, metal foil and power supply; wherein, one end of the metal electrode is located on the glazed surface of the glazed glass; the EVA film is located on the glazed surface of the glazed glass and on the surface of the metal electrode facing away from the glazed surface of the glazed glass; the ultra-clear glass is located on the surface of the EVA film facing away from the glazed surface of the glazed glass; the EVA film is used to bond the glazed glass, one end of the metal electrode and the ultra-clear glass to form a component under test; the metal foil wraps around the periphery of the component under test, the metal foil is connected to the negative pole of the power supply, and the other end of the metal electrode extends outwards from the component under test and is connected to the positive pole of the power supply; wherein, the metal foil does not contact the metal electrode.

2. The PID testing device for photovoltaic enamelled glass according to claim 1, characterized in that, An insulating layer is provided between the metal foil and the metal electrode, or, there is a gap of 1 - 5 mm between the metal foil and the metal electrode.

3. The PID test device for photovoltaic enameled glass according to claim 1, characterized in that, The metal foil is aluminum foil or copper foil.

4. The PID test device for photovoltaic enameled glass according to claim 1, wherein The power supply is a DC voltage power supply, and the voltage range is 1 KV - 1.5 KV.

5. The PID test device for photovoltaic enamelled glass according to claim 1, wherein, The metal electrode is a metal tinned strip.

6. A PID test method for photovoltaic enamelled glass, characterized in that, Implemented based on the photovoltaic glazed glass PID test device according to any one of claims 1 - 5, including the following steps: Step 1: Place the photovoltaic glazed glass PID test device in a test environment and connect the test wires, wherein, control the environmental temperature to be 0 - 100 °C and the relative humidity to be 0 - 100% RH; Step 2: Turn on the power supply, and under the action of high voltage, make the metal electrode generate corona discharge, and the ion flow acts on the surface of the glazed glass; Step 3: Continuously perform ion radiation on the glazed glass and observe in real time whether the appearance of the glazed glass changes color; Step 4: Record the color change situation of the appearance of the glazed glass and analyze the anti-PID performance of the glazed glass.

7. The PID test method for the photovoltaic enamelled glass according to claim 6, wherein, The environmental temperature in Step 1 is 85 °C and the relative humidity is 85% RH.

8. The PID test method for photovoltaic enamelled glass according to claim 6, wherein The power supply in Step 2 is a DC voltage power supply and the voltage is 1.5 KV.

9. The PID test method for photovoltaic enamelled glass according to claim 6, wherein, The time for continuously performing ion radiation on the glazed glass in Step 3 is a multiple of 96 hours, and the interval time for observing whether the appearance of the glazed glass changes color is 24 hours.

10. The PID testing method for photovoltaic enamelled glass according to claim 6, characterized in that, Step 4 includes: when the appearance of the glazed glass changes color, the glazed glass does not have anti-PID performance; when the appearance of the glazed glass does not change color significantly, the glazed glass has anti-PID performance.

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