CN114244247A

CN114244247A - Photovoltaic system and wind-solar hybrid power station

Info

Publication number: CN114244247A
Application number: CN202111296358.XA
Authority: CN
Inventors: 罗丽珍; 彭文博; 虞祥瑞; 肖平; 赵东明; 李晓磊; 高虎; 施悦; 葛恒; 田鸿翔; 陈雄飞
Original assignee: Huaneng Clean Energy Research Institute; Huaneng Group Technology Innovation Center Co Ltd
Current assignee: Huaneng Clean Energy Research Institute; Huaneng Group Technology Innovation Center Co Ltd
Priority date: 2021-11-03
Filing date: 2021-11-03
Publication date: 2022-03-25

Abstract

The embodiment of the invention provides a photovoltaic system and a wind-light complementary power station. The photovoltaic system comprises a plurality of groups of photovoltaic group strings and a plurality of MPPT controllers, wherein each group of photovoltaic group strings comprises a plurality of photovoltaic modules which are sequentially connected in series, and each photovoltaic module in each photovoltaic group string is connected with each photovoltaic module in an adjacent group of photovoltaic group strings in parallel; and each photovoltaic group string in the multiple groups of photovoltaic group strings is a unit and is connected with the MPPT controller. The photovoltaic system provided by the embodiment of the invention has the advantages of high power generation amount, strong anti-shielding capability, high system stability and long service life.

Description

Photovoltaic system and wind-solar hybrid power station

Technical Field

The invention relates to the technical field of photovoltaic systems, in particular to a photovoltaic system and a wind-light complementary power station.

Background

Photovoltaic systems are typical series-parallel systems of power supplies, and series-parallel mismatch is a very important factor affecting the electric quantity of the photovoltaic systems. In order to obtain larger voltage, generally 20-30 photovoltaic groups are connected in series to form a photovoltaic group string, and then the group strings are connected in parallel, wherein the mismatch of the series connection of the multiple components is represented as a 'barrel effect' in the photovoltaic system, namely, the fault of a small number of components in the system can cause the larger reduction of the total power generation amount of the system. The influence of shielding on the photovoltaic system is particularly serious, because even a small amount of shielding of a single component can cause the whole power of the whole string of photovoltaic strings, and meanwhile, the hot spot effect generated by shielding can bring potential safety hazards to the photovoltaic system. The influence of shielding on a photovoltaic system is eliminated, and the efficiency and the safety of the system are particularly important to be improved.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art.

To this end, the embodiment of the invention provides a photovoltaic system and a wind-light complementary power station.

A photovoltaic system according to an embodiment of the present invention includes:

each group of photovoltaic group strings comprises a plurality of photovoltaic modules which are sequentially connected in series, and each photovoltaic module in each photovoltaic group string is connected with each photovoltaic module in the adjacent group of photovoltaic group strings in parallel; and

and each photovoltaic group string in the photovoltaic group strings is a unit and is connected with the MPPT controller.

The photovoltaic system provided by the embodiment of the invention has the advantages of high power generation amount, strong anti-shielding capability, high system stability and long service life.

In some embodiments, a plurality of the MPPT controllers are connected at their outputs to a combiner box, which is connected to an inverter.

In some embodiments, the MPPT controllers that converge into the same combiner are communicatively coupled to each other.

In some embodiments, a wireless communication device is installed on the MPPT controller, and a plurality of MPPT controllers which are merged into the same combiner are in communication connection through the wireless communication device;

or a plurality of MPPT controllers which are converged into the same current combiner are in communication connection through a lead.

In some embodiments, the number of photovoltaic modules connected to each of the MPPT controllers is the same.

In some embodiments, the number of MPPT controllers is equal to and corresponds one-to-one with the number of photovoltaic strings.

In some embodiments, the number of the photovoltaic modules in the string of photovoltaic modules corresponding to each of the MPPT controllers is 2 to 50.

In some embodiments, the number of the pv modules in the string of pv modules corresponding to each MPPT controller is 25.

In some embodiments, any two adjacent photovoltaic modules in each group of the strings of photovoltaic groups are electrically connected by a first wire, and the first wire in the string of photovoltaic groups is connected to the corresponding first wire in the adjacent string of photovoltaic groups by a second wire.

In some embodiments, a first lead and a second lead are led out from the positive electrode or the negative electrode of the junction box of the photovoltaic module, the photovoltaic module is connected in series with the adjacent photovoltaic module in the same photovoltaic group string through the first lead, and the photovoltaic module is connected in parallel with the corresponding photovoltaic module in the adjacent photovoltaic group string through the second lead.

The invention also provides a wind-solar hybrid power station, which comprises a fan system and a photovoltaic system according to any one of claims 1 to 8, wherein the fan system comprises a plurality of fans which are arranged discretely, an area through which a shadow of the fans on the ground passes forms an occlusion area, and the photovoltaic system is arranged in the occlusion area.

In some embodiments, the shaded region defined by each of the fans is arcuate in shape.

Drawings

Fig. 1 is a schematic diagram of a photovoltaic system according to an embodiment of the present invention.

Fig. 2 is a schematic view of a photovoltaic system junction box according to an embodiment of the present invention.

Fig. 3 is a schematic diagram of the connection of adjacent photovoltaic modules in a photovoltaic system according to an embodiment of the present invention.

Fig. 4 is another schematic connection diagram of adjacent photovoltaic modules in a photovoltaic system according to an embodiment of the invention.

Fig. 5 is a schematic diagram of connections between multiple MPPT controllers in a photovoltaic system according to an embodiment of the present invention.

FIG. 6 is a schematic diagram of a wind-solar hybrid power plant according to an embodiment of the invention.

FIG. 7 is a schematic diagram of an occlusion region according to an embodiment of the invention.

Reference numerals:

a photovoltaic system 100;

the photovoltaic module comprises a photovoltaic module string 1, a photovoltaic module 11 and a junction box 111;

an MPPT controller 2;

a combiner box 3;

an inverter 4;

a first wire 51, a second wire 52;

a fan 6;

the area 7 is occluded.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

A photovoltaic system 100 according to an embodiment of the present invention is described below with reference to the drawings, and as shown in fig. 1 to 5, the photovoltaic system 100 according to an embodiment of the present invention includes a plurality of sets of photovoltaic strings 1 and a plurality of MPPT controllers 2 (power optimizers).

Each group of photovoltaic string 1 comprises a plurality of photovoltaic modules 11 which are connected in series in sequence, namely the photovoltaic strings 1 are formed by connecting a plurality of photovoltaic modules 11 in series. Each photovoltaic module 11 in a string 1 is connected in parallel with each photovoltaic module 11 in an adjacent string 1, i.e. each photovoltaic module 11 in a string 1 has a parallel channel with the adjacent string 1. Thus, when any one of the photovoltaic modules 11 in the photovoltaic string 1 is damaged or shielded, the current of the photovoltaic string 1 can be dispersed into the adjacent photovoltaic string 1.

Each group of photovoltaic strings 1 in the plurality of groups of photovoltaic strings 1 is a unit and is connected with the MPPT controller 2. That is, each string 1 has an MPPT controller 2 associated with it. The current of the photovoltaic string 1 is dispersed into the adjacent photovoltaic string 1, so that the currents output by the adjacent photovoltaic string 1 are different, and the MPPT controller 2 can improve the output power of the photovoltaic string 1 and keep higher power generation capacity of the photovoltaic string 1. And each group of photovoltaic strings 1 is a unit and is connected with the MPPT controller 2, namely the MPPT controller 2 is matched with a plurality of photovoltaic modules 11. Therefore, in the photovoltaic system 100, the MPPT controllers 2 uniformly distributed can adjust the voltage, the current and the power of each branch to be uniformly output, so that the stability and the service life of the photovoltaic system 100 are improved. Moreover, the cost of the photovoltaic system 100 (the number of MPPT controllers 2 is reduced) can be reduced on the basis of increasing the power generation amount of the photovoltaic system 100.

Therefore, the photovoltaic system 100 according to the embodiment of the invention has the advantages of high power generation amount, strong shielding resistance, high system stability and long service life.

As shown in fig. 1, in some embodiments, the outputs of the MPPT controllers 2 are connected to a combiner box 3, and the combiner box 3 is connected to an inverter 4. After each MPPT controller 2 optimizes the pv strings 1 corresponding thereto, the output end of each MPPT controller 2 transmits the dc power output by the pv strings 1 to the combiner box 3, and the combiner box 3 feeds the combined dc power into the inverter 4, so that the inverter 4 converts the dc power into ac power.

In some embodiments, multiple MPPT controllers 2 that converge into the same combiner 3 are communicatively coupled to each other. From this a plurality of MPPT controllers 2 can convey input current, voltage and power data mutually, through communication calculation, evenly distribute system's electric current, voltage between MPPT controllers 2, reach the same purpose of output power, and then increase system stability, extension system life-span.

Specifically, the voltage input to the DC terminal (combiner 3) by the MPPT controller 2 is equal to the average voltage of all the photovoltaic group strings 1, and the current input to the DC terminal by the MPPT controller 2 is equal to the average current of all the photovoltaic group strings 1. This ensures that the system is stable, where MPPT controller 2 serves to equalize system current and voltage and maximize system output.

In some embodiments, the MPPT controller 2 is installed with a wireless communication device, and multiple MPPT controllers 2 converging into the same combiner 3 are connected by communication through the wireless communication device. Therefore, the communication connection between the MPPT controllers 2 is simple and convenient.

Alternatively, a plurality of MPPT controllers 2 merged into the same combiner 3 are communicatively connected by a wire to transmit current and voltage data to each other, and as shown in fig. 1 and 5, one MPPT controller 2 is used as a reference and is connected to each MPPT controller.

In some embodiments, the number of photovoltaic modules 11 connected to each MPPT controller 2 is the same. The quantity of the photovoltaic group strings 1 connected with each MPPT controller 2 is the same, namely the quantity of the photovoltaic assemblies 11 is the same, so that the optimization effect of each MPPT controller 2 on the photovoltaic assemblies 11 is better, and the effect of the MPPT controllers 2 on the generated energy improved by the photovoltaic assemblies 11 is more balanced.

As shown in fig. 1, in some embodiments, the number of MPPT controllers 2 is equal to and corresponds one-to-one to the number of pv strings 1. Specifically, one MPPT controller 2 is connected to one group of pv strings 1, and each group of pv strings 1 is optimized by one MPPT controller 2, thereby increasing the power generation amount of each group of pv strings 1.

In some embodiments, each MPPT controller 2 corresponds to a number of photovoltaic modules 11 of 2-50. Thus, the cost of the photovoltaic system 100 can be reduced while increasing the amount of power generation. For example, the number of the photovoltaic modules 11 connected in series in the photovoltaic string 1 corresponding to each MPPT controller 2 is 15, which can better improve the power generation amount; or the number of the photovoltaic modules 11 corresponding to each MPPT controller 2 is 50, so that the cost is lower while the power generation amount is improved.

In some embodiments, each MPPT controller 2 corresponds to 25 photovoltaic modules 11.

As shown in fig. 3, in some embodiments, any two adjacent photovoltaic modules 11 in each group of photovoltaic string 1 are electrically connected by a first wire 51, and the first wire 51 in the photovoltaic string 1 is connected to the corresponding first wire 51 in the adjacent photovoltaic string 1 by a second wire 52. Thereby, each photovoltaic module 11 in a string 1 of photovoltaic groups can be connected in parallel with each photovoltaic module 11 in a string 1 of adjacent groups. When any photovoltaic module 11 in the photovoltaic string 1 is damaged or shielded, the current of the photovoltaic string 1 can be dispersed into the adjacent photovoltaic string 1 through the second conducting wire 52.

Alternatively, as shown in fig. 4, in some embodiments, a first conducting wire 51 and a second conducting wire 52 are led out from the positive electrode or the negative electrode of the junction box 111 of the photovoltaic module 11, the photovoltaic module 11 is connected in series with the adjacent photovoltaic module 11 in the same photovoltaic string 1 through the first conducting wire 51, and the photovoltaic module 11 is connected in parallel with the corresponding photovoltaic module 11 in the adjacent photovoltaic string 1 through the second conducting wire 52. For example, a first lead 51 and a second lead 52 are led out from the negative pole of the junction box 111 of the photovoltaic module 11, the first lead 51 of the photovoltaic module 11 is connected with the positive pole of the junction box 111 of the adjacent photovoltaic module 11 in the same photovoltaic string 1, and the second lead 52 of the photovoltaic module 11 is connected with the positive pole or the negative pole of the corresponding photovoltaic module 11 in the adjacent photovoltaic string 1.

As shown in fig. 6 and fig. 7, the invention further provides a wind-solar hybrid power station, which includes a fan system and a photovoltaic system 100 according to an embodiment of the invention, the fan system includes a plurality of fans 6 arranged discretely, an area through which a shadow of the plurality of fans 6 on the ground passes constitutes a sheltering area 7, and the photovoltaic system 100 is arranged in the sheltering area 7.

The wind-solar hybrid power station according to the embodiment of the invention can generate power by setting the fan 6, the wind-solar hybrid power station according to the embodiment of the invention can generate power by setting the photovoltaic system 100 according to the embodiment of the invention by using sunlight, and when any photovoltaic module 11 in the photovoltaic string 1 of the photovoltaic system 100 according to the embodiment of the invention is damaged or shielded, the current of the photovoltaic string 1 can be dispersed into the adjacent photovoltaic string 1; the MPPT controller 2 can improve the output power of the photovoltaic string 1 and keep the higher power generation amount of the photovoltaic string 1. Therefore, the photovoltaic system 100 according to the embodiment of the invention can be arranged in the sheltered area to have higher power generation capacity.

Therefore, the wind-solar hybrid power station has the advantage of high power generation capacity.

In some embodiments, as shown in fig. 7, the area formed by the daily projection of each fan 6 on the ground is recorded and analyzed according to different seasons, and the shape of the sheltered area 7 formed by each fan 6 is set to be arched, i.e. the projection of each fan 6 on the ground is always located in the arched area. The photovoltaic system 100 according to the embodiment of the present invention is disposed in the arched shaded area 7, thereby ensuring the power generation efficiency of the photovoltaic system 100.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the present disclosure, the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" and the like mean that a specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. A photovoltaic system, comprising:

2. The photovoltaic system of claim 1, wherein a plurality of the MPPT controllers are connected at outputs to a combiner box, the combiner box being connected to an inverter.

3. The pv system of claim 2, wherein a plurality of MPPT controllers merging into the same combiner are communicatively coupled to each other.

4. The photovoltaic system of claim 3,

the MPPT controller is provided with wireless communication equipment, and a plurality of MPPT controllers which are converged into the same junction station are in communication connection through the wireless communication equipment;

5. The photovoltaic system of claim 1, wherein the number of photovoltaic modules connected to each of the MPPT controllers is the same.

6. The photovoltaic system of claim 5, wherein the number of MPPT controllers is equal to and corresponds to the number of photovoltaic strings.

7. The photovoltaic system of claim 1, wherein the number of photovoltaic modules per MPPT controller is 2-50.

8. The photovoltaic system of claim 7, wherein the number of photovoltaic modules per MPPT controller is 25.

9. The photovoltaic system of claim 1, wherein any two adjacent photovoltaic modules in each of the strings of photovoltaic groups are electrically connected by a first wire, and wherein the first wire in the string of photovoltaic groups is connected to a corresponding first wire in an adjacent string of photovoltaic groups by a second wire.

10. The photovoltaic system according to claim 1, wherein a first wire and a second wire are led out from a positive electrode or a negative electrode of the junction box of the photovoltaic module, the photovoltaic module is connected in series with the adjacent photovoltaic modules in the same photovoltaic group string through the first wire, and the photovoltaic module is connected in parallel with the corresponding photovoltaic modules in the adjacent photovoltaic group string through the second wire.

11. A wind-solar hybrid power plant, characterized in that it comprises a fan system comprising a plurality of fans arranged discretely, the area over which the shadow of the ground passes constituting an sheltered area, and a photovoltaic system according to any one of claims 1 to 10, arranged in said sheltered area.

12. The hybrid wind-solar plant of claim 11, wherein said shaded area defined by each of said wind turbines is arcuate in shape.