Novel section photovoltaic module
Technical Field
The utility model belongs to the technical field of solar energy, concretely relates to novel section photovoltaic module.
Background
As the size of silicon wafers gradually increases, the number of cells placed in a circuit design package using the current technology is increasingly limited. Meanwhile, as the market demand for high-power components is continuously increased, the method for increasing the power of the components most quickly is mainly to increase the number of battery pieces under the condition that the efficiency improvement of the existing battery technology is limited. However, the increase of the number of the battery pieces brings about the increase of the assembly Voc (open circuit voltage), and the increase of the assembly Voc causes the reduction of the number of the series assemblies of each branch of the system end, so that cables, brackets, combiner boxes and the like are correspondingly added, which leads to the increase of the BOS cost of the system and further affects the LCOE. Therefore, a photovoltaic module needs to be designed, the problem that the Voc of the module is greatly increased due to the increase of the number of the batteries is solved while the power is increased due to the increase of the number of the batteries, and meanwhile, the power loss of the solar module is reduced and the hot spot power loss of the solar module is improved through matching of the number of the slices and the circuit design.
Disclosure of Invention
In order to solve the problem, the utility model provides a novel section photovoltaic module through adopting section battery and circuit design, avoids bringing the promotion by a wide margin of subassembly Voc because of battery quantity increases when increasing battery quantity lifting power, reduces solar module's power loss simultaneously, improves solar module hot spot power loss.
Therefore, the utility model adopts the following technical scheme:
a novel sliced photovoltaic module comprising one or more series-connected cells (4), said cells (4) comprising one or more series (3) of series or parallel-connected cells, said series (3) of cells comprising one or more series (2) of cells connected in parallel by busbars, said series of cells comprising a plurality of sliced cells (1) connected in series by interconnecting bars (10); wherein:
the sliced cell (1) is a conventional solar cell slice which is cut into 2-4 independent small cells with the same specification by laser, each small cell slice is provided with a positive electrode and a back electrode, and the positions of the positive electrode and the back electrode are mutually overlapped; the sliced batteries are connected in series through the interconnecting strips (10) to form a battery string (2).
As a specific embodiment, the battery unit (4) comprises one or more series-connected battery string series (3), the battery string series (3) is a continuous same string, at the middle position of the battery string series, the battery string series forms two parts which are symmetrical up and down by changing the direction of an interconnecting strip (10) or rotating the battery string, namely an upper part battery string (5) and a lower part battery string (6), the battery strings of the upper part battery string (5) are connected in parallel, the battery strings of the lower part battery string (6) are connected in parallel, the upper part battery string (5) and the lower part battery string (6) are connected in parallel by an intermediate bus bar (11), and the polarities of the battery sheets at the connection positions are the same; the upper part battery string (5) in one battery unit is connected with the upper part battery string (5) in the adjacent battery unit in series, and the lower part battery string (6) in one battery unit is connected with the lower part battery string (6) in the adjacent battery unit in series; each battery unit is connected with a bypass diode (7) in parallel, and the bypass diode (7) is connected with the middle bus bar in an intersecting mode through a jumper wire led out of the bus bar connected between the battery unit and the battery unit in series.
In a specific embodiment, the bypass diode (7) is located at the longitudinal middle position of the assembly, the jumper (8) has two jumper wires, namely a first jumper wire (8A) and a second jumper wire (8B), and the first jumper wire (8A) can be arranged between the battery strings or on the back of the battery strings; the second jumper (8B) can be arranged between the battery string and the edge of the glass, between the battery string and the battery string, or on the back of the battery string; when disposed between the battery string and the glass edge, the battery string of the battery cell connected with the second jumper wire (8B) is opposite in polarity to the battery string of the battery cell adjacent thereto; when disposed between the battery strings, the battery string of the battery cell connected with the second jumper wire (8B) is the same in polarity as the battery string of the battery cell adjacent thereto; the first jumper (8A) does not transmit current in the normal working state of the assembly, and is only used for transmitting current by-pass when the assembly has hot spots and the by-pass diode works; the second jumper (8B) is used for transmitting current in the normal working state of the assembly.
Further, of the bypass diodes, two bypass diodes adjacent to each other may be integrated in one wire cassette or each may be integrated in two wire cassettes, and the other diode is separately integrated in the wire cassette.
As another specific embodiment, the battery units (4) comprise two or more battery strings (2) which are connected in parallel, the battery strings (2) in the same battery unit are parallel to each other and have the same polarity, the battery units (4) are connected in series through bus bars, each battery unit (4) is connected with a bypass diode (7) in parallel, the battery units (4) work independently, the bypass diodes (7) are connected with the bus bars connected in series between the adjacent battery units through jumper wires (8), one end of each bypass diode is connected with the positive electrode or the negative electrode of the battery unit, and the other end of each bypass diode is connected with the connected jumper wire.
Further, the jumper (8) is arranged at a position between two adjacent battery units; or the back of the battery string is isolated by adopting an insulating material.
Further, the jumper (8) does not transmit current in the normal state of the assembly.
Further, the bypass diodes are arranged at two long side edges of the module, respectively, wherein two bypass diodes adjacent to each other can be integrated in one wire box or each in two wire boxes, and the other bypass diode is separately integrated in the wire boxes.
Compared with the prior art, the utility model discloses following beneficial effect has:
the utility model discloses the solar wafer that will have conventional size (156 ~ 300mm) now becomes the small battery of 2-4 independent the same specifications through laser cutting, then through circuit design, establish ties a plurality of battery pieces above-mentioned, parallelly connected, form the battery cluster in proper order, battery cluster series and battery unit, form battery pack again on this basis, through optimizing circuit design, thereby under the prerequisite that does not increase subassembly Isc by a wide margin, promote subassembly power, reduce subassembly Voc, the single branch road of system end can establish ties more subassemblies, the BOS cost of reduction system end.
The Isc of the small battery after laser cutting is one fraction of the cut piece; multiple parallel circuits are realized through optimized circuit design, the component resistance is further reduced, and the component resistance is I according to P ═ I2R, the component power loss can be greatly reduced.
Through circuit design, adopt the jumper wire to insert parallelly connected bypass diode, convenient operation can realize the bypass function when the shadow shelters from appearing simultaneously, avoids producing overheated damage subassembly.
Drawings
Fig. 1 is a circuit diagram of embodiment 1 of the present invention;
fig. 2 is a connection mode of a battery string series in embodiment 1 of the present invention;
fig. 3A and 3B show another connection method of the battery string series according to embodiment 1 of the present invention;
fig. 4 is another circuit diagram according to embodiment 1 of the present invention;
fig. 5 is a circuit diagram of embodiment 2 of the present invention;
fig. 6 shows a connection manner of the battery string in embodiment 2 of the present invention;
wherein: 1 is a small battery, 2 is a battery string, 3 is a battery string series, 4 is a battery unit, 5 is an upper part battery string, 6 is a lower part battery string, 7 is a bypass diode, 8 is a jumper wire, 8A is a first jumper wire, 8B is a second jumper wire, 9 is a bus bar, 10 is an interconnection bar, and 11 is a middle bus bar.
Detailed Description
Example 1
In the embodiment, as shown in fig. 1-4, a conventional solar cell (156-300 mm) is cut into four independent small cells 1 with the same specification by laser, each small cell has a positive electrode and a back electrode, and the positions of the positive electrode and the back electrode are overlapped with each other. The cut small cells 1 are connected in series via the interconnection strips 10 to form a cell string 2. The two battery strings 2 are connected in parallel by the interconnection bar, and the battery string formed by connecting the two battery strings 2 in parallel is a battery string series 3. The two battery string series 3 are connected by bus bars to form one battery unit 4. Three battery cells 4 are connected in series to form the sliced photovoltaic module of the present embodiment, as shown in fig. 1.
In this embodiment, the battery string series 3 may be a continuous same string, rather than two strings of battery strings spliced together; as shown in fig. 2, the direction of the interconnection strip 10 can be changed at the middle position of the series of battery strings, that is: the interconnection direction of a certain cell and the interconnection bar in the interconnection is changed, and a larger distance is formed between the two cells with the changed interconnection direction, wherein the larger distance is relative to the distance between the other small cells. The polarity of the small battery 1 in the battery string series is negative, positive, negative, positive … … positive, negative, positive, negative or positive, negative, positive, negative … … negative, positive, negative and positive from top to bottom in sequence, the interconnection direction of a certain battery is changed, and the distance between the two batteries is larger than that between the other batteries.
Alternatively, by rotating the battery string 2, as shown in fig. 3A and 3B, wherein fig. 3A shows two battery strings; fig. 3B shows that two strings are assembled by rotating the strings to keep the mutual connection directions of the two strings opposite to each other and splicing the two strings on the bus bar 9, so as to form a string series, and the two strings are spliced at a large distance relative to the distance between other small cells, such as 10-30 mm. At this time, the polarity of the battery string is from top to bottom: negative, positive, negative … … positive, negative, positive or positive, negative, positive … … negative, positive, negative. The battery cluster series after the concatenation, the polarity is by last to being in proper order: negative, positive, negative, positive … … positive, negative, positive, negative or positive, negative, positive, negative … … negative, positive, negative, positive.
After the above operation, the battery string series 3 forms two symmetrical parts, namely an upper battery string 5 and a lower battery string 6. As shown in fig. 1, in the same battery unit, two upper battery strings 5 are connected in parallel with each other, two lower battery strings 6 are connected in parallel with each other, the upper battery strings 5 and the lower battery strings 6 are connected in parallel through an intermediate bus bar 11, and the polarities of the battery pieces at the connection positions are the same; the upper partial cell string 5 in one cell is connected in series with the same upper partial cell string 5 in the adjacent cell by the bus bar 9, and likewise, the lower cell string 6 in one cell is connected in series with the same lower cell string 6 in the adjacent cell by the bus bar 9.
As shown in fig. 1, each battery cell 4 is connected in parallel with a bypass diode 7, and each battery cell operates independently of the other. The bypass diode 7 is connected across an intermediate bus bar 11 by a jumper wire 8 leading from the bus bar 9 in series between the battery cells. In the embodiment, two jumper wires are provided, which are respectively named as a first jumper wire 8A and a second jumper wire 8B, specifically, the bypass diode 7 is located at the middle position in the longitudinal direction of the assembly, the first jumper wire 8A can be provided between the battery string and the battery string, or on the back of the battery string, and when the first jumper wire is provided on the back of the battery string, the jumper wire needs to be isolated by using an insulating material; the second jumper wire 8B may be disposed between the battery string and the edge of the glass, between the battery string and the battery string, or on the back of the battery string. When disposed between the battery string and the glass edge, the battery string of the battery cell connected with the second jumper wire 8B is opposite in polarity to the battery string of the battery cell adjacent thereto, as shown in fig. 1; when disposed between the battery strings, the battery string of the battery cell connected with the second jumper wire 8B and the battery string of the battery cell adjacent thereto have the same polarity, as shown in fig. 4; when the battery is arranged on the back of the battery string, the jumper wires need to be isolated by adopting an insulating material. The first jumper wire 8A does not transmit current in the normal working state of the assembly, and is only used for transmitting current by-pass when the assembly has hot spots and the by-pass diode works. The second jumper 8B is used to transmit current when the assembly is in a normal operating state.
When two bypass diodes 7 are adjacent to each other, as shown in fig. 1, 4, they may be integrated in one wire box or each in two wire boxes, the other diode being separately integrated in the wire box.
The utility model discloses in, battery unit 4 is including parallelly connected upper portion battery cluster 5, and parallelly connected lower part battery cluster 6, and upper portion battery cluster 5 also parallelly connected each other with lower part battery cluster 6, through introducing parallel circuit, the parallelly connected quantity of battery cluster has been increased, according to parallelly connected Voc the same principle, when increasing battery quantity lifting power, can avoid bringing promotion by a wide margin of subassembly Voc because of battery quantity increases, the parallelly connected quantity of circuit increases simultaneously, the whole cluster of subassembly hinders also has certain reduction, and then reduce power loss. Meanwhile, each battery unit is connected with a bypass diode, so that the battery string can realize the bypass function when being shielded by the shadow, and the component is prevented from being damaged by overheating.
Example 2:
unlike the vertical arrangement of the battery strings in embodiment 1, the present embodiment is a horizontal arrangement of the battery strings.
In the embodiment, as shown in fig. 5 and fig. 6, a conventional solar cell (156-300 mm) is cut into two or four independent small cells 1 with the same specification by laser, each small cell has a positive electrode and a back electrode, and the positions of the positive electrode and the back electrode are overlapped with each other. The cut small cells 1 are connected in series via the interconnection strips 10 to form a cell string 2. The four battery strings 2 are connected in parallel to form one battery unit 4. Three battery cells 3 are connected in series to form the sliced photovoltaic module of the present embodiment. In the present embodiment, since the battery strings are connected in parallel by the bus bars, two or more of the battery strings 2 connected in parallel may be regarded as one battery string series 3.
As shown in fig. 5, the battery strings 2 are parallel to each other and have the same polarity in the same battery unit 4. The battery units 4 are connected in series with the battery units 4 through the bus bars 9, and each battery unit 4 is connected in parallel with a bypass diode 7, and each battery unit 4 operates independently from each other. The bypass diode 7 is connected with a serial bus bar 9 between adjacent battery units through a jumper wire 8, one end of the bypass diode 7 is connected with the anode or cathode of the battery unit, and the other end of the bypass diode 7 is connected with the jumper wire 8. The jumper wires 8 are arranged at positions between the battery cells 4 and the battery cells 4 or at the back of the battery string, and need to be isolated with an insulating material when placed at the back. The jumper wire 8 does not transmit current when the assembly is in a normal working state, and is only used for transmitting current by-pass when the assembly has hot spots and the by-pass diode works.
The bypass diodes 7 are arranged at the two long side edges of the module, wherein two bypass diodes adjacent to each other can be integrated in one wire box or each in two wire boxes, and the other bypass diode is separately integrated in the wire boxes.
In this embodiment, 4 battery strings 2 in battery unit 4 are connected in parallel, have increased the parallelly connected quantity of battery cluster, according to parallelly connected Voc the same principle, when increasing battery quantity and promoting power, can avoid bringing promoting by a wide margin of subassembly Voc because of the increase of battery quantity, introduce parallel circuit and increased the parallelly connected quantity of battery cluster simultaneously, the whole series resistance of subassembly also has certain reduction, and then reduces power loss. Each battery unit 4 is connected with a bypass diode, so that the battery string can realize the bypass function when being shielded by shadow, and the component is prevented from being damaged by overheating.
In the present invention, the bus bar 9 and the intermediate bus bar 11 can be made of the same material, and are distinguished only for the convenience of description, and there is no difference in nature.
It should be noted that the specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims. According to the utility model provides a small battery and parallel battery cluster's design, can set up the piece number of battery piece as required, reach best technological effect.