A high system power generation efficiency anti-shading photovoltaic module

Abstract

The present invention is a high system power generation efficiency anti-shading photovoltaic assembly, including a solar cell assembly, the solar cell assembly is composed of a plurality of battery strings arranged in a matrix, the plurality of battery strings are composed of a plurality of battery cells connected in series, in the same battery string, two adjacent battery cells are connected in series through an interconnection bar, each interconnection bar is connected to a conductor, a reflective structure is provided on the conductor, each conductor is provided with a diode on the side facing away from the light, and the diode is electrically connected to the battery cell. The present invention arranges the diode below the conductor, thereby avoiding problems such as aging and overheating damage of the diode under long-term sunlight exposure.

Description

Technical Field

[0001] The invention relates to the technical field of solar cell modules, and in particular to an anti-shading photovoltaic module with high system power generation efficiency. Background Art

[0002] The circuit design of photovoltaic modules is generally to connect the cells in series into 6 large strings, and then these 6 strings of cells are connected in series. Because it is a series circuit, when one cell in the entire circuit is damaged or blocked, it will affect the power generation efficiency of the entire module. Therefore, when these 6 strings of cells are connected in series, there is a diode in parallel with every two strings of cells. When the cells in these two strings are damaged or blocked, the diode will turn on and bypass these two strings, so that the other 4 strings of cells can still work normally. The power generation power of the module is only reduced by 1 / 3.

[0003] In order to make the power generation of the module as high as possible when it is in a fault state, some people have proposed to connect a diode in parallel to each battery or several batteries to minimize the number of bypassed cells and thus improve the power generation efficiency of the photovoltaic module in the fault state. However, the above diodes are directly exposed to the sun. Under long-term sunlight, the diodes have UV aging, overheating damage, etc. Moreover, the above diodes need to be manually welded during the integration process into the module, and the operation is difficult. There is a high risk of electrostatic breakdown, and due to the installation of diodes, the distance between the cells is increased, which increases the internal resistance and reduces the power generation efficiency of the module. Summary of the invention

[0004] In order to solve the problem of diode aging caused by long-term exposure to sunlight, the present invention provides a high system power generation efficiency anti-shading photovoltaic component, including a solar cell component, wherein the solar cell component is composed of a plurality of battery strings arranged in a matrix and connected in series, and the plurality of battery strings are composed of a plurality of battery cells connected in series, and in the same battery string, two adjacent battery cells are connected in series through an interconnection strip, a conductor is provided in the gap between the two adjacent battery cells, the conductor is electrically connected to the interconnection strip located in the gap, a reflective structure is provided on the conductor, and a diode is provided on a side of each conductor facing away from the light, and the diode is electrically connected to the battery cell.

[0005] Preferably, the polarity of the same surface of several cells is the same. In order to facilitate the cells to receive light and generate electricity, the light-receiving surface of the cells is arranged toward the sun, and the light directly irradiates the cells, which greatly improves the utilization rate of light.

[0006] Furthermore, the upper surface of the battery cell is the negative electrode, and the lower surface is the positive electrode. The interconnection bar is Z-shaped, and the interconnection bar connects the negative electrode of the battery cell with the positive electrode of the adjacent battery cell. Generally, the light-receiving surface of the battery cell is the surface where the negative electrode is located. In order to facilitate the connection of the conductor on the Z-shaped interconnection bar, the light-receiving surface of the conductor is perpendicular to the direction of sunlight to make full use of sunlight. If it is not a Z-shaped interconnection bar, such as an arc-shaped interconnection bar, the conductor is set on the interconnection bar, and the direction of sunlight exposure is at a certain angle to the conductor. The amount of sunlight irradiating the conductor is greatly reduced, which is not conducive to the use of light.

[0007] Preferably, the Z-shaped interconnection bar comprises a connecting portion and two horizontal portions, the two horizontal portions are respectively connected to the negative electrode and the positive electrode of two adjacent battery cells, and the conductor is arranged below the horizontal portion connected to the negative electrode of the battery cell. The conductor is welded to the horizontal portion of the Z-shaped interconnection bar, and the length of the horizontal portion connected to the negative electrode of the battery cell is greater than the horizontal portion connected to the positive electrode of the battery cell, so that a conductor of larger size can be welded to the horizontal portion.

[0008] Furthermore, one end of the diode is connected to the conductor, and the other end is connected to the positive electrode of the adjacent cell. The diode is connected in parallel with the adjacent cell to prevent the cell from being blocked and being used as a load to consume the energy generated by other illuminated cells. When the adjacent cell is blocked, the current flows out of the diode without affecting the other cells to continue to generate electricity.

[0009] Preferably, the reflective structure is a reflective film. The reflective surface of the reflective film corresponds to the position of the battery cell. The reflective film layer can be pasted on the conductor to reflect the solar energy irradiated on the reflective film layer to the battery cell, thereby improving the light utilization rate.

[0010] Furthermore, the reflective structure is a sawtooth or arc-shaped convex strip. The convex strip reflects the light irradiated on the convex strip to the battery cell. The length direction of the convex strip is parallel to the battery cell, so that the light is reflected to both sides of the convex strip, reducing the probability of sunlight being reflected on a part other than the battery cell, and making full use of sunlight.

[0011] Preferably, the spacing between two adjacent battery strings is 2-10 mm.

[0012] Furthermore, in the same battery string, the distance between two adjacent battery cells is 6-20 mm, which increases the distance between two adjacent battery cells, reduces the number of battery cells, and can fully utilize the sunlight within the distance, thereby increasing power generation.

[0013] Preferably, in order to fully utilize the sunlight between two adjacent cells, the width of the conductor is 0.5-1mm smaller than the distance between two adjacent cells in the same cell string, the length is greater than the 0-0.5mm length of the cell side, and the thickness is 0.2-0.4mm.

[0014] Beneficial effects: 1. The present invention utilizes a conductor to connect the wires in the interconnection strip in parallel, thereby reducing the series resistance and improving the power generation efficiency.

[0015] 2. The present invention arranges the diode below the conductor, thereby preventing the diode from aging and overheating damage due to long-term sunlight exposure.

[0016] 3. The present invention connects diodes in parallel on the battery sheet, thereby avoiding the hot spot effect and improving the power generation efficiency.

[0017] 4. The present invention increases the gap between the battery cells to facilitate manual welding and other operations. The increase in the gap reduces the number of battery cells and reduces costs. The amount of power generated by reflecting sunlight in the gap to the battery cells is much higher than the amount of power generated by the reduced battery cells, thereby improving the power generation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A side view of a battery string connection structure of the present invention;

[0019] Figure 2 A top view of a battery string connection structure of the present invention;

[0020] Figure 3 This is a schematic diagram of the Z-shaped interconnection strip structure of the present invention;

[0021] 1. Battery cell; 2. Conductor; 3. Interconnection strip; 4. Horizontal part; 5. Connecting part; 6. Battery string; 7. Diode. DETAILED DESCRIPTION

[0022] Embodiment 1

[0023] As shown in the figure, a series welding structure of a solar cell assembly includes a solar cell assembly, wherein the solar cell assembly is composed of a plurality of battery strings 6 arranged in a matrix and connected in series, wherein the plurality of battery strings 6 are composed of a plurality of battery cells 1 connected in series, wherein in the same battery string 6, two adjacent battery cells 1 are connected in series through an interconnection bar 3, and a conductor 2 is provided in the gap between the two adjacent battery cells 1, wherein the conductor 2 is electrically connected to the interconnection bar 3 located in the gap, and a reflective structure is provided on the conductor 2, and each of the conductors 2 is provided with a diode 7 on the side facing away from the light, wherein the diode 7 is electrically connected to the battery cell 1. The interconnection bar 3 is composed of a plurality of conductors, and the interconnection bar 3 connects a plurality of battery cells 1 in series. The upper surface of the conductor 2 is parallel to the side of the battery cell 1 facing the sun, and the interconnection bar 3 is welded on the conductor 2 and is in conduction with the conductor 2, and the other end of the conductor 2 is welded with the interconnection bar 3, and the interconnection bar 3 is electrically connected to the next battery cell 1.

[0024] The polarity of the same surface of several battery cells 1 is the same. The upper surface of the battery cell 1 is the negative electrode, and the lower surface is the positive electrode. The interconnection bar 3 is Z-shaped, and the interconnection bar 3 connects the negative electrode of the battery cell 1 with the positive electrode of the adjacent battery cell 1. The Z-shaped interconnection bar 3 includes a connecting portion 5 and two horizontal portions 4. The two horizontal portions 4 are respectively connected to the negative electrode and the positive electrode of two adjacent battery cells 1. The conductor 2 is arranged below the horizontal portion 4 connecting the negative electrode of the battery cell 1. One end of the diode 7 is connected to the conductor 2, and the other end is connected to the positive electrode of the adjacent battery cell 1. The negative electrode of the battery cell 1 faces the sun. The length of the horizontal portion 4 connecting the negative electrode of the battery cell 1 is greater than the horizontal portion 4 connecting the positive electrode of the battery cell 1, so that the conductor 2 with a larger size can be welded on the horizontal portion 4. The conductor 2 connects several wires in the interconnection bar 3 in parallel, reducing the series resistance. At the same time, the reflection structure on the conductor 2 is utilized, and the light energy between adjacent battery cells 1 is greatly utilized to improve the power of the battery cell 1. By using Z-shaped interconnection bars 3 and welding the conductors 2 to the horizontal portions 4 of the interconnection bars 3 , the sunlight is irradiated on the conductors 2 for the longest time and over the largest irradiation area, thus making full use of the sunlight.

[0025] The reflective structure is a reflective film. The reflective surface of the reflective film corresponds to the position of the battery cell 1. The reflective film layer can be pasted on the conductor 2. The reflective film layer can be used to reflect the solar energy irradiated on the reflective film layer to the battery cell 1, thereby improving the light utilization rate.

[0026] The reflective structure is a sawtooth or arc-shaped convex strip. The reflective structure can also be a convex strip, which reflects the light irradiated on the convex strip to the battery cell 1. The length direction of the convex strip is parallel to the battery cell 1, so that the light is reflected to both sides of the convex strip, reducing the probability of sunlight reflection not being on the battery cell 1, and making full use of sunlight.

[0027] The spacing between two adjacent battery strings 6 is 2-10mm. In the same battery string 6, the spacing between two adjacent battery cells 1 is 6-20mm. After testing, in the same battery string 6, the spacing between two adjacent battery cells 1 is 9-12mm. At this spacing, the power generation of the entire solar cell assembly is the largest. The width of the conductor 2 is 0.5-1mm smaller than the spacing between two adjacent battery cells 1 in the same battery string 6, the length is greater than the side length of the battery cell 1 by 0-0.5mm, and the thickness is 0.2-0.4mm. In the prior art, the string resistance is generally reduced by reducing the spacing between two adjacent battery cells 1 in the same battery string 6, thereby improving the power generation rate. However, this method cannot utilize the light energy within the spacing between two adjacent battery cells 1. The present invention increases the spacing between two adjacent battery cells 1 in the same battery string 6, making it convenient for operators to perform welding and other operations, and also fully utilizes the light energy within the spacing between two adjacent battery cells 1 in the same battery string 6. The reflective structure on the conductor 2 reflects the light to the battery cell 1, thereby improving the power generation efficiency and the light utilization rate. A number of wires in the interconnection bar 3 are connected in parallel through the conductor 2, so that the string resistance is reduced.

[0028] Experimental demonstration:

[0029] Three groups of solar cell modules are placed outdoors. There are 6 battery strings 6 in the solar cell modules. Each battery string 6 consists of 10 battery cells 1. The spacing between adjacent battery cells 1 in the same battery string 6 is set to 9 mm, and the spacing between two adjacent battery strings is 4 mm. The size of the battery cell is 156.75×156.75 mm, and the negative poles of all battery cells 1 are set to face the sun.

[0030] Comparative experiment 1: using the above solar cell assembly, a diode 7 is connected in parallel to each cell 1, without other structures;

[0031] Comparative Experiment 2: The difference compared with Comparative Experiment 1 is that: the conductor 2 is electrically connected to the interconnection strip 3 (the connection method of the conductor 2 is consistent with the above-mentioned embodiment 1, the length of the conductor 2 is 157 mm, the width is 8 mm, and the thickness is 0.2 mm), there is a reflective structure on the conductor 2, the diode 7 is not arranged under the conductor 2 (arranged on one side of the battery cell 1), and the rest is the same as Comparative Experiment 1.

[0032] The present invention is different from the comparative experiment 2 in that the diode 7 is arranged below the conductor 2 , and the rest is the same as the comparative experiment 2.

[0033] Comparative Experiment 3: The difference from Comparative Experiment 1 is that the distance between two adjacent battery cells 1 in the same string is set to 2 mm, and no diode 7 is connected in parallel to all battery cells 1. Others are the same as Comparative Experiment 1.

[0034] Comparative Experiment 4: The difference compared with Comparative Experiment 3 is that: the spacing between two adjacent battery cells 1 in the same string is set to 9mm, a conductor 2 is provided between two adjacent battery cells 1 in the same battery string 6 (the conductor 2 is 157mm long, 8mm wide, and 0.2mm thick), the conductor 2 is electrically connected to the interconnection bar 3, and there is no reflective structure on the conductor 2. The rest is the same as Comparative Experiment 3.

[0035]

[0036] Conclusion: By comparing comparative experiment 3 and comparative experiment 4, it can be learned that the scheme of reducing the series resistance by reducing the gap between two adjacent battery cells 1 in the same battery string 6 and the scheme of reducing the series resistance by increasing the gap between two adjacent battery cells 1 in the same battery string 6 and electrically connecting the conductor 2 in the gap to make the wires in the interconnection bar 3 in parallel, the power generation of the battery cells 1 in the two schemes is similar, and both have the effect of reducing the series resistance.

[0037] In addition, by comparing the other three sets of data, it can be seen that within one year, compared with Comparative Experiment 1 and Comparative Experiment 2, the solar cell module with conductor 2 has a power generation gain of 3.1% compared with the solar cell module without conductor 2, and compared with Comparative Experiment 2 and the present invention, the solar cell module with diode 7 arranged under conductor 2 has a power generation gain of 0.8% compared with the solar cell module without diode 7 arranged under conductor 2, and the longer the time, the more obvious the power generation benefit of the present invention is compared with Comparative Experiment 1 and Comparative Experiment 2. Finally, we can know that the present invention uses conductor 2 to connect the wires in the interconnection strip 3 in parallel, sets diode 7 under conductor 2, connects diode 7 in parallel on each cell 1, and uses the reflective structure on conductor 2 to reflect light, which all increase the power generation of cell 1 and have a meaningful effect.

Claims

1. A high system power generation efficiency anti-shading photovoltaic assembly, characterized by: The solar cell assembly comprises a plurality of battery strings (6) arranged in a matrix and connected in series, wherein the plurality of battery strings (6) are formed by a plurality of battery sheets (1) connected in series, wherein in the same battery string (6), two adjacent battery sheets (1) are connected in series via an interconnection bar (3), a conductor (2) is provided in the gap between the two adjacent battery sheets (1), the conductor (2) is electrically connected to the interconnection bar (3) located in the gap, a reflective structure is provided on the conductor (2), and a diode (7) is provided on the side of each conductor (2) facing away from light, and the diode (7) is electrically connected to the battery sheet (1); The polarity of the same surface of a plurality of the battery sheets (1) is the same; The upper surface of the battery cell (1) is a negative electrode, and the lower surface is a positive electrode; the interconnection bar (3) is in a Z shape; the interconnection bar (3) connects the negative electrode of the battery cell (1) with the positive electrode of an adjacent battery cell (1); The Z-shaped interconnection bar (3) comprises a connecting portion (5) and two horizontal portions (4), the two horizontal portions (4) being respectively connected to the negative electrode and the positive electrode of two adjacent battery cells (1), and the conductor (2) being arranged below the horizontal portion (4) connected to the negative electrode of the battery cell (1); One end of the diode (7) is connected to the conductor (2), and the other end is connected to the positive electrode of the adjacent battery cell (1).

2. The high system power generation efficiency anti-shading photovoltaic assembly according to claim 1, characterized in that: The reflective structure is a reflective film.

3. The high system power generation efficiency anti-shading photovoltaic assembly according to claim 1, characterized in that: The reflective structure is a sawtooth or arc-shaped convex strip.

4. The high system power generation efficiency anti-shading photovoltaic assembly according to claim 1, characterized in that: The spacing between two adjacent battery strings (6) is 2-10 mm.

5. The high system power generation efficiency anti-shading photovoltaic assembly according to claim 1, characterized in that: In the same battery string (6), the distance between two adjacent battery sheets (1) is 6-20 mm.

6. A high system power generation efficiency anti-shading photovoltaic assembly according to claim 1 or 5, characterized in that: The width of the conductor (2) is 0.5-1 mm smaller than the distance between two adjacent battery cells (1) in the same battery string (6), the length is 0-0.5 mm greater than the side length of the battery cell (1), and the thickness is 0.2-0.4 mm.

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