Layered partition-based distribution of transformer area distributed photovoltaic overvoltage remediation method and device

Abstract

The application relates to a layered partition-based transformer area distributed photovoltaic overvoltage treatment method and device, wherein the method comprises the following steps: acquiring a transformer area topology graph; based on the transformer area topology graph, loads and photovoltaics with an electrical distance of a trunk grid-connected point within a preset range are divided into the same electrical unit to obtain multiple electrical units; the grid-connected point voltage and the trunk injected power of each electrical unit are statistically obtained in real time; when several electrical units with the grid-connected point voltage exceeding a threshold value appear in the transformer area, the photovoltaic output is adjusted; when the grid-connected point voltage of all the electrical units in the transformer area is lower than the threshold value, the load overvoltage in the electrical unit is adjusted. The application can improve the pertinence and efficiency of photovoltaic adjustment.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of distributed photovoltaic grid-connected overvoltage remediation, in particular to a subarea-based distribution photovoltaic overvoltage remediation method and device. BACKGROUND

[0002] In the context of the current wide access of distributed photovoltaic to the distribution area, the overvoltage problem of the distribution area caused by photovoltaic backfeed is increasingly obvious. The overvoltage problem currently mainly relies on adjusting photovoltaic output and transformer tap to achieve. The problems of these adjustment methods are: there are blind and disordered characteristics in photovoltaic adjustment, the adjustment is not strong in pertinence, and the adjustment efficiency is low; the on-load voltage regulation distribution transformer increases investment compared with the traditional no-load voltage regulation transformer, the frequent operation of the transformer tap increases the risk of failure, and the tap can only realize discrete adjustment and cannot realize continuous adjustment. SUMMARY

[0003] The technical problem solved by the present application is to provide a subarea-based distribution photovoltaic overvoltage remediation method and device to improve the pertinence and efficiency of photovoltaic adjustment.

[0004] The technical solution adopted by the present application to solve the technical problem is: providing a subarea-based distribution photovoltaic overvoltage remediation method, comprising the following steps:

[0005] obtaining a distribution area topology map;

[0006] based on the distribution area topology map, dividing the loads and photovoltaics with an electrical distance of the trunk grid-connected point within a preset range to the same electrical unit to obtain a plurality of electrical units;

[0007] real-time statistics of the grid-connected point voltage and the trunk injected power of each electrical unit;

[0008] when there are several electrical units with grid-connected point voltage exceeding the threshold value in the distribution area, adjusting the photovoltaic output; the specific adjustment method is: starting from the line end, for the electrical units with the trunk injected power greater than 0, proportionally reducing the photovoltaic output according to the step, and for the electrical units with the trunk injected power less than 0, not adjusting the photovoltaic output;

[0009] when the grid-connected point voltage of all electrical units in the distribution area is lower than the threshold value, adjusting the load overvoltage inside the electrical unit.

[0010] The obtaining of the distribution area topology map is specifically: obtaining the connection relationship of the photovoltaics and loads in the distribution area by using the topology identification function of the low-voltage monitoring unit to obtain the distribution area topology map.

[0011] the grid-connected point voltage of each trunk in the i-th electrical unit is not more than 2%U i , wherein, Ui a grid-connection point voltage of the i-th electrical unit, the grid-connection point voltage of the i-th electrical unit being a maximum value of the grid-connection point voltage of the trunk line within the i-th electrical unit.

[0012] In the process of adjusting the photovoltaic output, the grid-connection point voltage of each electrical unit is updated in real time until the grid-connection point voltage of all electrical units is lower than the threshold value.

[0013] The load overvoltage inside the electrical unit is adjusted, specifically, the internal photovoltaic output of the electrical unit where the internal load side overvoltage occurs is reduced until all load side voltages inside the electrical unit meet the requirements.

[0014] The technical solution adopted by the present application to solve its technical problems is to provide a kind of based on hierarchical zoning's transformer area distributed photovoltaic overvoltage remediation device, including:

[0015] The acquisition module is used to acquire the transformer area topology graph.

[0016] The division module is used to divide the load and photovoltaic with electrical distance within a preset range of the grid-connection point of the trunk line to the same electrical unit based on the transformer area topology graph, to obtain a plurality of electrical units.

[0017] The statistical module is used to statistically the grid-connection point voltage and the trunk line injection power of each electrical unit in real time.

[0018] The photovoltaic output adjustment module is used to adjust the photovoltaic output when a plurality of electrical units with grid-connection point voltage exceeding the threshold value appear in the transformer area. The specific adjustment method is: starting from the end of the line, for the electrical unit with the trunk line injection power greater than 0, the photovoltaic output is reduced in proportion according to the step, and for the electrical unit with the trunk line injection power less than 0, the photovoltaic output is not adjusted.

[0019] The load overvoltage adjustment module is used to adjust the load overvoltage inside the electrical unit when the grid-connection point voltage of all electrical units in the transformer area is lower than the threshold value.

[0020] The technical solution adopted by the present application to solve its technical problems is to provide an electronic device, including memory, processor and computer program stored on the memory and executable on the processor, when the processor executes the computer program, the steps of the above-mentioned transformer area distributed photovoltaic overvoltage remediation method based on hierarchical zoning are realized.

[0021] The technical solution adopted by the present application to solve its technical problems is to provide a computer readable storage medium, which stores a computer program, when the computer program is executed by a processor, the steps of the above-mentioned transformer area distributed photovoltaic overvoltage remediation method based on hierarchical zoning are realized.

[0022] Advantages

[0023] Compared with the prior art, the application has the following advantages and positive effects: based on the topology identification function, the application adjusts the photovoltaic area in a hierarchical and zoned manner, measures the photovoltaic return active power in real time during the photovoltaic output peak period, calculates and adjusts the photovoltaic output in real time according to the zoned result, reduces the photovoltaic output power by minimization, reduces the voltage rise caused by the active power return, and thus controls the user-side overvoltage caused by the photovoltaic return. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a flowchart of a hierarchical and zoned area distributed photovoltaic overvoltage remediation method according to the first embodiment of the application. DETAILED DESCRIPTION

[0025] The application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the application and not to limit the scope of the application. In addition, it should be understood that those skilled in the art can make various modifications or changes to the application after reading the content taught by the application, and these equivalent forms also fall within the scope defined by the claims of the application.

[0026] The first embodiment of the application relates to a hierarchical and zoned area distributed photovoltaic overvoltage remediation method, as shown in Figure 1 includes the following steps:

[0027] Step 1, obtain the area topology map. This step can use the topology identification function of the low-voltage monitoring unit (LTU) to obtain the connection relationship of the photovoltaic and load in the area, obtain the area topology map, and upload the obtained area topology map to the area fusion terminal.

[0028] Step 2, based on the area topology map, the loads and photovoltaics with an electrical distance within a preset range from the trunk line grid connection point are divided into the same electrical unit, and a plurality of electrical units are obtained. In this step, the loads and photovoltaics with a small electrical distance from the trunk line grid connection point are divided into the same electrical unit, and the grid connection point voltages of the trunk lines in the same electrical unit after division differ by no more than 2% U i , wherein U i is the grid connection point voltage of the i-th electrical unit. In this embodiment, the grid connection point voltage of the i-th electrical unit is the maximum value of the grid connection point voltages of the trunk lines in the i-th electrical unit.

[0029] Step 3, real-time statistics of the grid connection point voltage and the trunk line injection power of each electrical unit. In this step, the trunk line injection power is greater than 0, indicating that the photovoltaic output in the electrical unit is greater than the load, and the trunk line injection power is less than 0, indicating that the photovoltaic output in the electrical unit is less than the load.

[0030] Step 4, when there are several grid-connected point voltages exceeding the threshold value in the station area, the photovoltaic output is adjusted, and the specific adjustment method is: starting from the end of the line, for the electrical units with the line injection power greater than 0, the photovoltaic output is reduced in proportion according to the step size, and for the electrical units with the line injection power less than 0, the photovoltaic output is not adjusted. For example, assuming that there are three electrical units, namely electrical unit A, electrical unit B and electrical unit C, wherein electrical unit A is closest to the end of the line, and electrical unit C is farthest from the end of the line, when the photovoltaic output is adjusted, assuming that the line injection power of electrical unit A, electrical unit B and electrical unit C is greater than 0, at this time, electrical unit A can reduce the photovoltaic output by 30%, electrical unit B can reduce the photovoltaic output by 20%, and electrical unit C can reduce the photovoltaic output by 10%; assuming that the line injection power of electrical unit A and electrical unit C is greater than 0, and the line injection power of electrical unit B is less than 0, at this time, electrical unit A can reduce the photovoltaic output by 30%, electrical unit B does not adjust the photovoltaic output, and electrical unit C reduces the photovoltaic output by 20%.

[0031] In the adjustment process of step 4, the grid-connected point voltages of each electrical unit are updated in real time, and the adjustment is stopped when the grid-connected point voltages of all electrical units are lower than the threshold value, and the next step is entered.

[0032] Step 5, when the grid-connected point voltages of all electrical units in the station area are lower than the threshold value, the internal load overvoltage of the electrical unit is adjusted, and the specific adjustment method is: reducing the internal photovoltaic output of the electrical unit that appears internal load side overvoltage until all load side voltages in the electrical unit meet the requirements.

[0033] It can be found that the embodiment based on the topology identification function adjusts the photovoltaic station area in a hierarchical and zoned management mode, measures the photovoltaic return active power in real time during the peak period of photovoltaic output, calculates and adjusts the photovoltaic output in real time according to the zoning result, reduces the photovoltaic output power by the minimum, reduces the voltage rise caused by the return of active power, and thus controls the user side overvoltage caused by the return of photovoltaic. This method does not occupy the capacity of the distribution transformer, and therefore does not affect the economic and reliable operation of the station area.

[0034] The second embodiment of the present application relates to a hierarchical and zoned station area distributed photovoltaic overvoltage remediation device, comprising:

[0035] An acquisition module is configured to acquire a station area topology map.

[0036] A division module is configured to divide loads and photovoltaics with electrical distances within a preset range at a grid-connected point to the same electrical unit based on the station area topology map, to obtain a plurality of electrical units.

[0037] A statistics module is configured to statistically record the grid-connected point voltage and the main line injection power of each electrical unit in real time.

[0038] A photovoltaic output adjustment module is configured to adjust the photovoltaic output when there are electrical units with grid-connected point voltage exceeding the threshold value in the transformer area; the specific adjustment manner is: starting from the line end, the photovoltaic output is proportionally reduced in steps for the electrical units with main line injection power greater than 0, and no adjustment is made for the electrical units with main line injection power less than 0.

[0039] A load overvoltage adjustment module is configured to adjust the load overvoltage in the electrical unit when the grid-connected point voltage of all electrical units in the transformer area is lower than the threshold value.

[0040] The acquisition module acquires the connection relationship of the photovoltaic and load in the transformer area by using the topology identification function of the low-voltage monitoring unit, and obtains a transformer area topology diagram.

[0041] The grid-connected point voltage of each main line in the i-th electrical unit is not more than 2%U i , wherein U i is the grid-connected point voltage of the i-th electrical unit, and the grid-connected point voltage of the i-th electrical unit is the maximum value of the grid-connected point voltage of the main line in the i-th electrical unit.

[0042] The photovoltaic output adjustment module updates the grid-connected point voltage of each electrical unit in real time during the adjustment process until the grid-connected point voltage of all electrical units is lower than the threshold value, and then stops adjusting the photovoltaic output.

[0043] When the load overvoltage adjustment module adjusts the load overvoltage in the electrical unit, the internal photovoltaic output of the electrical unit with internal load side overvoltage is reduced until all load side voltages in the electrical unit meet the requirements.

[0044] The third embodiment of the present application relates to an electronic device, which comprises a memory, a processor and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the hierarchical partition-based transformer area distributed photovoltaic overvoltage remediation method of the first embodiment when executing the computer program.

[0045] The fourth embodiment of the present application relates to a computer readable storage medium, which stores a computer program, and the computer program implements the steps of the hierarchical partition-based transformer area distributed photovoltaic overvoltage remediation method of the first embodiment when executed by a processor.

[0046] Those skilled in the art will appreciate that embodiments of the application can be devised for a method, a system, or a computer program product. Accordingly, the present application can be embodied in the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application can take the form of a computer program product on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage etc.) embodying computer readable program code.

[0047] The present application is described in reference to the flowchart and / or block diagram illustrations of the methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each block of the flowchart and / or block diagrams, and combinations of blocks in the flowchart and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks.

[0048] These computer program instructions can also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks.

[0049] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more functions specified in the flowchart and / or block diagram block or blocks.

[0050] The above description is only specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for regulating overvoltage in distributed photovoltaic power generation in a substation based on hierarchical partitioning, characterized in that: The following steps are involved: Get the topology map of the substation area; Based on the substation topology, loads and photovoltaics within a preset range of electrical distance from the main line grid connection point are divided into the same electrical unit to obtain multiple electrical units; Real-time statistics of grid connection point voltage and mains injection power of each electrical unit; When several electrical units in the substation have grid-connected point voltages exceeding the threshold, the PV output is adjusted. The specific adjustment method is as follows: starting from the end of the line, for electrical units with mains injection power greater than 0, the PV output is proportionally reduced in steps, and for electrical units with mains injection power less than 0, no PV output adjustment is made. When the grid connection point voltages of all electrical units in the substation area are lower than the threshold, the load overvoltage inside the electrical unit is adjusted.

2. The method for regulating overvoltage in distributed photovoltaic power generation based on hierarchical partitioning according to claim 1 is characterized in that: The obtaining of the substation topology map specifically involves using the topology identification function of the low voltage monitoring unit to obtain the connection relationship between photovoltaics and loads in the substation to obtain the substation topology map.

3. The method for regulating overvoltage in distributed photovoltaic power generation based on hierarchical partitioning according to claim 1 is characterized in that: The voltage difference between the grid connection points of the main lines in the i-th electrical unit shall not exceed 2% U i , where U i is the grid connection point voltage of the i-th electrical unit, and the grid connection point voltage of the i-th electrical unit is the maximum value of the grid connection point voltage of the trunk line in the i-th electrical unit.

4. The method for regulating overvoltage in distributed photovoltaic power generation based on hierarchical partitioning according to claim 1, characterized in that: When the photovoltaic output is adjusted, the grid connection point voltage of each electrical unit is updated in real time during the adjustment process, and the adjustment is stopped until the grid connection point voltages of all electrical units are lower than the threshold.

5. The method for regulating overvoltage in distributed photovoltaic power generation based on hierarchical partitioning according to claim 1 is characterized in that: The adjustment of the load overvoltage inside the electrical unit is specifically: reducing the internal photovoltaic output of the electrical unit where the internal load side overvoltage occurs until all load side voltages in the electrical unit meet the requirements.

6. A distributed photovoltaic overvoltage regulation device based on hierarchical partitioning, characterized in that: include: An acquisition module is used to obtain a topological map of the substation area; A division module is used to divide the loads and photovoltaics whose electrical distance from the main line grid point is within a preset range into the same electrical unit based on the substation topology map to obtain multiple electrical units; Statistics module, used to count the grid connection point voltage and mains injection power of each electrical unit in real time; The photovoltaic output adjustment module is used to adjust the photovoltaic output when there are several electrical units with grid-connected point voltage exceeding the threshold in the substation area. The specific adjustment method is: start adjustment from the end of the line, for the electrical units with mains injection power greater than 0, reduce the photovoltaic output in proportion to the step size; for the electrical units with mains injection power less than 0, No photovoltaic output adjustment is made; The load overvoltage adjustment module is used to adjust the load overvoltage inside the electrical unit when the grid connection point voltage of all electrical units in the substation is lower than the threshold.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method for regulating distributed photovoltaic overvoltage in a substation based on hierarchical partitioning as described in any one of claims 1 to 5 are implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for regulating overvoltage of distributed photovoltaic power generation in a substation based on hierarchical partitioning are implemented as described in any one of claims 1 to 5.

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