A photovoltaic array and intelligent adjustment method thereof

Abstract

The present invention discloses a photovoltaic array and an intelligent adjustment method thereof, comprising: an inverter, a photovoltaic array, and a protection device; setting the photovoltaic array according to demand, collecting the measured voltage value of each group of photovoltaic arrays and comparing it with the maximum open-circuit voltage value, selecting the measured voltage value whose measured voltage value is less than the maximum open-circuit voltage value, and constructing a data set; removing the maximum value and the minimum value of the data set, calculating the average value, the difference between the average value and the maximum value, and the difference between the average value and the minimum value, and comparing them with a preset threshold value, the photovoltaic array can work when the threshold value is greater than the difference, otherwise, the photovoltaic array stops working. The present invention has strong anti-shadow ability and parameter matching ability, simple electrical system connection, and is easy to monitor and maintain through an intelligent terminal.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic power generation, and in particular to a photovoltaic array and an intelligent adjustment method thereof. Background Art

[0002] Solar cell modules (also called solar panels, photovoltaic modules) are the core and most important part of solar power generation systems. Their function is to convert solar energy into electrical energy, or to store it in batteries, or to drive loads. The strings in the configured photovoltaic module array will be installed on different facades and directions of the building, but they may be blocked by buildings and produce shadows as the rising track changes in different seasons and time periods. Although there are bypass diodes in the photovoltaic module junction box to prevent the hot spot effect caused by the shading of the components in the module array from damaging the components, the diodes that are in the on state for a long time will generate a lot of heat, causing the temperature inside the junction box to rise, causing the junction box of the photovoltaic module to age prematurely, and the packaging materials to fail prematurely, causing fires. Summary of the invention

[0003] The purpose of the present invention is to provide an intelligent photovoltaic array protection system and method to solve the technical problems existing in the prior art and realize automatic intelligent adjustment of the photovoltaic array.

[0004] To achieve the above object, the present invention provides the following solution: a photovoltaic array and an intelligent adjustment method thereof, comprising:

[0005] S1. Setting several groups of photovoltaic arrays, collecting the measured voltage values ​​of each group of photovoltaic arrays, and constructing a first data set by comparing the measured voltage values ​​with the maximum open circuit voltage value;

[0006] S2. constructing a second data set by removing the first maximum value and the first minimum value of the first data set, and calculating a first average value of the second data set;

[0007] S3. Calculate a first difference between the first average value and the first maximum value, and a second difference between the first average value and the first minimum value, and compare the first target threshold with the first difference and the second difference, respectively, by setting a first target threshold, and control the plurality of photovoltaic array groups based on the comparison results.

[0008] Preferably, S1 includes selecting the measured voltage value whose measured voltage value is greater than the maximum open circuit voltage value to construct the first data set.

[0009] Preferably, the first target threshold comprises a first threshold and a second threshold;

[0010] Preferably, when the number of working photovoltaic arrays is less than or equal to 50% of the total number of photovoltaic arrays, the difference between the average value of the set of measured voltage values ​​of the working photovoltaic arrays and the maximum open-circuit voltage is the first threshold value;

[0011] Preferably, when the number of working photovoltaic arrays is greater than 50% of the total number of photovoltaic arrays, the maximum value of the difference between the average value of the measured voltage value set of the working photovoltaic arrays and any value of the measured voltage value set is the second threshold.

[0012] Preferably, S3 includes:

[0013] The number of working photovoltaic arrays is less than or equal to 50% of the total number of photovoltaic arrays, and the first threshold is compared with the relationship between the first difference and the second difference respectively. When the first threshold is respectively greater than the first difference and the second difference, the photovoltaic arrays corresponding to the first data set can all work; when the first difference or the second difference is greater than the first threshold, the photovoltaic array corresponding to the first maximum value or the first minimum value does not work.

[0014] Preferably, when the first difference and the second difference are smaller than the first threshold, the photovoltaic arrays corresponding to the first maximum value and the first minimum value respectively do not operate.

[0015] Preferably, the second maximum value and the second minimum value of the second data set are removed to construct a third data set, and the second average value of the third data set is calculated;

[0016] Preferably, a third difference between the second average value and the second maximum value and a fourth difference between the second average value and the second minimum value are calculated, and the third difference and the fourth difference are compared with the first target threshold value respectively, and the plurality of photovoltaic arrays are controlled based on the comparison result.

[0017] Preferably, the maximum open-circuit voltage of each group of photovoltaic arrays is the same.

[0018] Preferably, each group of photovoltaic arrays includes a plurality of photovoltaic strings;

[0019] S11. Collect the measured voltage value of each photovoltaic string, and construct a fourth data set by comparing the measured voltage value of the photovoltaic string with the maximum open circuit voltage value corresponding to the photovoltaic string;

[0020] S21. Constructing a fourth data set by removing the third maximum value and the third minimum value of the fourth data set, and calculating a third average value of the fourth data set;

[0021] S31. Calculate the fifth difference between the third average value and the third maximum value, and the sixth difference between the third average value and the third minimum value, and compare the second target threshold with the relationship between the fifth difference and the sixth difference respectively by setting a second target threshold, and control the plurality of photovoltaic strings based on the comparison results.

[0022] Preferably, the maximum open circuit voltage of each photovoltaic string is the same;

[0023] Preferably, the S11 includes selecting the measured voltage value whose measured voltage value is greater than the maximum open circuit voltage value to construct the fourth data set.

[0024] A photovoltaic array group with intelligent regulation function, comprising:

[0025] An inverter, a plurality of photovoltaic arrays, and a protection device, wherein the protection device comprises a first protection device and a second protection device, and the inverter is connected to the plurality of photovoltaic arrays through the first protection device;

[0026] The photovoltaic array includes a plurality of photovoltaic strings;

[0027] The first protection device is connected to the plurality of photovoltaic strings via the second protection device;

[0028] The first protection device is used to collect the measured voltage of each photovoltaic array group, and based on the measured voltage of each photovoltaic array group, control the working state of each photovoltaic array group to ensure the safe operation of the photovoltaic array group;

[0029] The second protection device is used to control the working state of each photovoltaic string based on the control information of the first protection device to ensure the safe operation of each photovoltaic array.

[0030] The present invention discloses the following technical effects:

[0031] The present invention can automatically adapt to any number of photovoltaic component strings, monitor the voltage parameters of the strings in real time, actively identify abnormal photovoltaic component strings according to a prefabricated algorithm, and disconnect the abnormal component strings from the system equipment through a cut-off device to protect the abnormal photovoltaic component strings. When the component strings are judged to be restored to normal, the cut-off strings are actively restored to restore the normal operation of the system without manual intervention. The intelligent photovoltaic array of the present invention has strong anti-shadow ability and parameter matching ability, simple electrical system wiring, and is easy to monitor and maintain through intelligent terminals. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It is a schematic diagram of the system structure of the present invention. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] The strings in the configured PV module array are installed on different facades and directions of the building. As the rising trajectory changes in different seasons and time periods, they may be blocked by buildings and produce shadows. The PV sub-array controller will compare and judge based on the preset voltage value or actively learn the consistency of the voltage of adjacent strings to determine the module strings in the blocked state, and actively analyze the working status of the strings according to the preset algorithm. If an abnormality is found, the connection between the blocked module strings and the inverter will be actively cut off, thereby enhancing the module installation flexibility of the PV building and the stability of the module products. When the blocking phenomenon disappears, the cut-off module strings will actively reconnect to the inverter.

[0037] Photovoltaic string abnormality judgment, according to the actual configuration of the photovoltaic string in the project (number of series and parallel blocks), and the specification parameters of the photovoltaic module, the maximum open circuit voltage value Vp of the photovoltaic module string is calculated. The Vp value fully considers the influence of temperature characteristics. When it is judged that the voltage value of the photovoltaic module is higher than the maximum possible value of the photovoltaic module, it is concluded that the system has a judgment error and a system fault alarm data is issued; when the detected photovoltaic string value is within the maximum value range, the voltage data between the real-time measurement strings and the historical data are compared, and the historical data includes the maximum open circuit voltage data measured in different seasons, different weather, and different time periods. When it is found that the open circuit voltage values ​​between adjacent strings or any strings exceed the normal difference at the same measurement time, it can be judged that part of the photovoltaic module array is blocked, and the abnormal string is actively disconnected from the system to avoid irreversible damage to the module caused by the hot spot phenomenon. When it is detected that it has returned to the normal difference range, the disconnected component string is restored to the system.

[0038] Several groups of photovoltaic arrays are set up according to the requirements, and the photovoltaic arrays include but are not limited to roof photovoltaic tile arrays, photovoltaic wall arrays, photovoltaic floor arrays, and photovoltaic fence arrays. The measured voltage values ​​of each group of photovoltaic arrays are collected, and the maximum open-circuit voltage of each group of photovoltaic arrays is the same by comparing the measured voltage values ​​with the maximum open-circuit voltage values. The measured voltage values ​​whose measured voltage values ​​are greater than the maximum open-circuit voltage values ​​are selected to construct a data set.

[0039] Remove the maximum and minimum values ​​of the data set, construct a new data set, and calculate the average value, the first difference between the average value and the maximum value, and the second difference between the average value and the minimum value of the new data set. By setting the target threshold, the threshold includes two values. When the working photovoltaic array is less than or equal to 50% of the total number of photovoltaic arrays, the difference between the average value of the measured voltage value set of the working photovoltaic array and the maximum open-circuit voltage is the first threshold; when the working photovoltaic array is greater than 50% of the total number of photovoltaic arrays, the maximum value of the difference between the average value of the measured voltage value set of the working photovoltaic array and any value of the measured voltage value set is the second threshold. Compare the size relationship between the target threshold and the difference respectively, wherein the working photovoltaic array is less than or equal to 50% of the total number of photovoltaic arrays, and compare the relationship between the first threshold and the first difference and the second difference respectively. When the first threshold is greater than the first difference and the second difference respectively, the photovoltaic arrays corresponding to the data set can all work; when the first difference or the second difference is greater than the first threshold, the photovoltaic array corresponding to the maximum value or the minimum value does not work; when the first difference and the second difference are less than the first threshold, the photovoltaic arrays corresponding to the maximum value and the minimum value do not work. Thus, control of several groups of photovoltaic arrays is achieved.

[0040] Furthermore, the second maximum value and the second minimum value of the new data set are removed, the data set is rebuilt, and the average value, the second difference between the average value and the maximum value, and the third difference between the average value and the minimum value are calculated. By setting the target threshold, the size relationship between the target threshold and the difference is compared respectively, and based on the comparison result, the plurality of photovoltaic arrays are controlled. Similarly, according to the design requirements, the above steps can be repeated multiple times to realize the automatic intelligent adjustment of the photovoltaic array.

[0041] Each photovoltaic array group also includes a plurality of photovoltaic strings; the photovoltaic strings include a plurality of photovoltaic modules, and the photovoltaic strings are formed by connecting the photovoltaic modules in series.

[0042] The photovoltaic module is a double-glass photovoltaic module, including a glass front end, which is ultra-white tempered glass; a rear end, which includes a photovoltaic backplane, which is PVB; and multiple photovoltaic structures, which are single-crystal cells, which are encapsulated between the glass front end and the rear end by a sealant.

[0043] The measured voltage value of each photovoltaic string is collected, and the maximum open circuit voltage value is compared with the measured voltage value. The maximum open circuit voltage of each photovoltaic string is the same. The measured voltage value whose measured voltage value is greater than the maximum open circuit voltage value is selected to construct a data set. The maximum and minimum values ​​of the new data set are removed, and the data set is constructed again. The average value, the difference between the average value and the maximum value, and the difference between the average value and the minimum value are calculated. By setting a target threshold, the size relationship between the target threshold and the difference is compared respectively. Based on the comparison result, the plurality of photovoltaic strings are controlled.

[0044] Photovoltaic array group with intelligent regulation function, including:

[0045] An inverter, a plurality of photovoltaic arrays, and a protection device, wherein the protection device comprises a first protection device and a second protection device, and the inverter is connected to the plurality of photovoltaic arrays through the first protection device;

[0046] The photovoltaic array includes several groups of photovoltaic strings;

[0047] The first protection device is connected to a plurality of photovoltaic strings through the second protection device;

[0048] The first protection device is used to collect the measured voltage of each photovoltaic array group, and based on the measured voltage of each photovoltaic array group, control the working state of each photovoltaic array group to ensure the safe operation of the photovoltaic array group;

[0049] The second protection device is used to control the working state of each photovoltaic string based on the control information of the first protection device to ensure the safe operation of each photovoltaic array.

[0050] The protection device comprises an insulating explosion-proof shell, a circuit board arranged inside the shell, and a plurality of interfaces arranged at two ends of the shell.

[0051] The circuit board includes a chip, a storage module, and a power module integrated on the circuit board.

[0052] The present invention can automatically adapt to any number of photovoltaic component strings, monitor the voltage parameters of the strings in real time, actively identify abnormal photovoltaic component strings according to a prefabricated algorithm, and disconnect the abnormal component strings from the system equipment through a cut-off device to protect the abnormal photovoltaic component strings. When the component strings are judged to be restored to normal, the cut-off strings are actively restored to restore the normal operation of the system without manual intervention. The intelligent photovoltaic array of the present invention has strong anti-shadow ability and parameter matching ability, simple electrical system wiring, and is easy to monitor and maintain through intelligent terminals.

[0053] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for intelligently adjusting a photovoltaic array, characterized in that: The following steps are involved: S1. Setting several groups of photovoltaic arrays, collecting the measured voltage values ​​of each group of photovoltaic arrays, and constructing a first data set by comparing the measured voltage values ​​with the maximum open circuit voltage value; S2. constructing a second data set by removing the first maximum value and the first minimum value of the first data set, and calculating a first average value of the second data set; S3. Calculate a first difference between the first average value and the first maximum value, and a second difference between the first average value and the first minimum value, and compare the first target threshold with the first difference and the second difference respectively by setting a first target threshold, and control the plurality of photovoltaic arrays based on the comparison result; The S1 includes selecting a measured voltage value whose measured voltage value is greater than the maximum open circuit voltage value to construct the first data set; The first target threshold includes a first threshold and a second threshold; When the number of working photovoltaic arrays is less than or equal to 50% of the total number of photovoltaic arrays, the difference between the average value of the set of measured voltage values ​​of the working photovoltaic arrays and the maximum open-circuit voltage is the first threshold; When the number of working photovoltaic arrays is greater than 50% of the total number of photovoltaic arrays, the maximum value of the difference between the average value of the measured voltage value set of the working photovoltaic arrays and any value of the measured voltage value set is the second threshold; The S3 includes: The number of working photovoltaic arrays is less than or equal to 50% of the total number of photovoltaic arrays, and the first threshold is compared with the relationship between the first difference and the second difference respectively. When the first threshold is respectively greater than the first difference and the second difference, the photovoltaic arrays corresponding to the second data set can all work, and the photovoltaic arrays corresponding to the first maximum value and the first minimum value respectively do not work; when the first difference or the second difference is greater than the first threshold, the photovoltaic array corresponding to the first maximum value or the first minimum value does not work.

2. The intelligent adjustment method of a photovoltaic array according to claim 1, characterized in that: Remove the second maximum value and the second minimum value of the second data set, construct a third data set, and calculate a second average value of the third data set; A third difference between the second average value and the second maximum value and a fourth difference between the second average value and the second minimum value are calculated, and the third difference and the fourth difference are compared with the first target threshold value respectively, and the plurality of photovoltaic arrays are controlled based on the comparison result.

3. The intelligent adjustment method of a photovoltaic array according to claim 1, characterized in that: The maximum open-circuit voltage of each group of photovoltaic arrays is the same.

4. The intelligent adjustment method of a photovoltaic array according to claim 1, characterized in that: Each group of photovoltaic arrays includes a plurality of photovoltaic strings; S11. Collect the measured voltage value of each photovoltaic string, and construct a fourth data set by comparing the measured voltage value of the photovoltaic string with the maximum open circuit voltage value corresponding to the photovoltaic string; S21. Constructing a fourth data set by removing the third maximum value and the third minimum value of the fourth data set, and calculating a third average value of the fourth data set; S31. Calculate the fifth difference between the third average value and the third maximum value, and the sixth difference between the third average value and the third minimum value, and compare the second target threshold with the relationship between the fifth difference and the sixth difference respectively by setting a second target threshold, and control the plurality of photovoltaic strings based on the comparison results.

5. The intelligent adjustment method of a photovoltaic array according to claim 4, characterized in that: The maximum open circuit voltage of each photovoltaic string is the same; The S11 includes selecting the measured voltage value that is greater than the maximum open circuit voltage value to construct the fourth data set.

6. A photovoltaic array using the intelligent adjustment method of a photovoltaic array as claimed in any one of claims 1 to 5, characterized in that: include: An inverter, a plurality of photovoltaic arrays, and a protection device, wherein the protection device comprises a first protection device and a second protection device, and the inverter is connected to the plurality of photovoltaic arrays through the first protection device; The photovoltaic array includes a plurality of photovoltaic strings; The first protection device is connected to the plurality of photovoltaic strings via the second protection device; The first protection device is used to collect the measured voltage of each photovoltaic array group, and based on the measured voltage of each photovoltaic array group, control the working state of each photovoltaic array group to ensure the safe operation of the photovoltaic array group; The second protection device is used to control the working state of each photovoltaic string based on the control information of the first protection device to ensure the safe operation of each photovoltaic array.

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