Distribution network voltage out-of-limit autonomous method, equipment and medium

Abstract

The invention relates to a distribution network voltage out-of-limit autonomous method and device and a medium, and the method comprises the steps: measuring the voltage sensitivity of each photovoltaic inverter in a low-voltage distribution area; when a voltage out-of-limit event occurs, each photovoltaic inverter spontaneously establishes a distribution network voltage governance cluster participating in this time through a communication interoperation mode, and determines a leading photovoltaic inverter of the distribution network voltage governance cluster based on the position of the photovoltaic inverter and the voltage sensitivity; and according to the voltage out-of-limit condition, the photovoltaic inverter in the distribution network voltage governance cluster controls the output reactive power and active power according to the voltage sensitivity of the photovoltaic inverter, and voltage out-of-limit governance is completed. According to the invention, adaptive voltage out-of-limit governance control can be realized, and governance timeliness and large-scale governance feasibility are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of distributed photovoltaic power generation grid-connected control, and in particular to a distribution network voltage over-limit autonomous method, device, equipment and medium. Background Art

[0002] With the rapid adoption of new energy in rural areas, a large number of distributed renewable energy sources are being connected to rural power distribution networks. During the day, when most household photovoltaic systems are operating at full capacity, voltage levels in the distribution area can seriously exceed their limits, posing a significant challenge to the stable operation and control of the local power grid. Because distributed photovoltaic systems often have small individual capacities, are numerous, and are geographically dispersed, unified management and control of these massive and diverse distributed photovoltaic generation units, as well as voltage over-limit mitigation measures, present significant challenges.

[0003] Current approaches to managing voltage overshoots in large numbers of distributed photovoltaic power plants in rural distribution networks typically involve first dividing them into clusters and then uniformly assigning management responsibilities within the clusters. Methods for clustering distributed photovoltaic power plants within a distribution area can be broadly categorized into cluster analysis, optimization algorithms, and complex community discovery. These methods all require prior knowledge of the distribution area topology and network parameters, then uniformly calculate the active and reactive voltage sensitivities of each node. Clustering is then performed within the distribution area to allocate reactive and active power regulation to the generating units involved in voltage overshoot management. While clustering is theoretically feasible, in practical applications, the distribution area topology and network parameters cannot be accurately determined in advance, and clustering must be re-assigned whenever the area topology changes. This further reduces the effectiveness of clustering for accurate voltage overshoot management. Even if accurate clustering is achieved, hardware computing power from the upper-level control center is required to uniformly assign management responsibilities within the cluster, significantly reducing the real-time performance of voltage overshoot management. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a distribution network voltage over-limit autonomous method, device, equipment and medium, which can realize adaptive voltage over-limit management control, improve the management timeliness and feasibility of large-scale management.

[0005] The technical solution adopted by the present invention to solve the technical problem is to provide a distribution network voltage over-limit autonomous method, including the following steps:

[0006] Each photovoltaic inverter in the low-voltage distribution area measures its own voltage sensitivity;

[0007] When a voltage over-limit event occurs, each photovoltaic inverter spontaneously establishes a distribution network voltage management cluster through communication and interoperability, and determines the leading photovoltaic inverter of the distribution network voltage management cluster based on the location and voltage sensitivity of the photovoltaic inverter;

[0008] According to the voltage over-limit situation, the photovoltaic inverters in the distribution network voltage management cluster control the output reactive power and active power according to their own voltage sensitivity to complete the voltage over-limit management.

[0009] Each photovoltaic inverter within the low-voltage distribution station area measures its own voltage sensitivity. Specifically, when the daily load fluctuation is less than a preset value, each photovoltaic inverter outputs a quantitative amount of active power and reactive power, and measures the active voltage change and reactive voltage change of the node where the photovoltaic inverter is located. The active-voltage sensitivity of the photovoltaic inverter is determined based on the active voltage change and the active power output value, and the reactive-voltage sensitivity of the photovoltaic inverter is determined based on the reactive voltage change and the reactive power output value.

[0010] The active-voltage sensitivity is determined by S Pn =ΔU Pn / ΔP n The reactive-voltage sensitivity is calculated by S Qn =ΔU Qn / ΔQ n Calculated, where S Pn and S Qn are the active-voltage sensitivity and reactive-voltage sensitivity of the n-th photovoltaic inverter, ΔU Pn and ΔU Qn are the active voltage change and reactive voltage change of the node where the nth photovoltaic inverter is located, ΔP n and ΔQ n is the active power output value and reactive power output value of the nth photovoltaic inverter.

[0011] When each photovoltaic inverter performs quantitative output of active power and reactive power, each photovoltaic inverter performs quantitative output of active power and reactive power in time periods according to the voltage sensitivity measurement plan schedule.

[0012] When each photovoltaic inverter performs quantitative output of active power and reactive power respectively, when a photovoltaic inverter is quantitatively outputting active power and reactive power, it notifies other photovoltaic inverters not to perform voltage sensitivity measurement through a broadcast response method. When the photovoltaic inverter completes the voltage sensitivity measurement, it notifies other photovoltaic inverters that the measurement has ended through a broadcast response method.

[0013] The photovoltaic inverters spontaneously establish and participate in the distribution network voltage management cluster through communication interoperability. Specifically, several photovoltaic inverters under the grid-connected node with the most serious voltage over-limit situation initiate a request to establish a voltage management cluster through a broadcast signal; the photovoltaic inverters respond with a handshake through a broadcast signal and establish a voltage management cluster; after receiving the request to establish a voltage management cluster, other photovoltaic inverters decide whether to join the voltage management cluster based on the voltage over-limit situation of the grid-connected point.

[0014] The leading photovoltaic inverter is the photovoltaic inverter at the grid-connected node with the highest voltage sensitivity and the most serious voltage over-limit degree.

[0015] The leading photovoltaic inverter is selected in the following manner:

[0016] When any PV inverter in the substation discovers that the voltage at the grid connection point exceeds the limit through autonomous monitoring, the PV inverter (i, j) will broadcast a message carrying the topic of voltage exceeding the limit through communication.

[0017] When the photovoltaic inverter (m, n) monitors the voltage over-limit management topic released by the photovoltaic inverter (i, j), it will automatically set its own voltage over-limit index M mn The voltage over-limit index M of the monitored photovoltaic inverter (i, j) ij For comparison, if the voltage exceeds the limit level indicator M mn Less than or equal to the voltage over-limit index M of the monitored photovoltaic inverter (i, j) ij , the photovoltaic inverter (i, j) stops publishing its own topic and subscribes to the voltage over-limit management topic of the photovoltaic inverter (m, n), confirming that it is proxied by the photovoltaic inverter (m, n), and the photovoltaic inverter (i, j) communication switches to passive monitoring mode; if its own voltage over-limit degree indicator M mn Greater than the voltage over-limit index M of the monitored photovoltaic inverter (i, j) ij , then PV inverter (i, j) becomes the agent of PV inverter (m, n), PV inverter (m, n) stops publishing its own topic, and PV inverter (m, n) communication switches to passive listening mode;

[0018] Repeat the above steps until it is confirmed that the photovoltaic inverter (l, k) becomes the agent of all topics that publish photovoltaic inverter voltage over-limit management, and the photovoltaic inverter (l, k) becomes the leading photovoltaic inverter.

[0019] According to the voltage over-limit situation, the photovoltaic inverters in the distribution network voltage management cluster control the output reactive power and active power according to their own voltage sensitivity to complete the voltage over-limit management, specifically as follows:

[0020] Calculate the voltage limit level based on the current voltage of the grid-connected node and the voltage upper limit of the grid-connected node;

[0021] Determine the reactive power required for the grid connection point voltage to drop below the voltage upper limit based on the reactive-voltage sensitivity of each photovoltaic inverter and the voltage over-limit degree;

[0022] When the maximum reactive power of the photovoltaic inverter is greater than or equal to the required reactive power, adjusting the reactive regulation amount of the leading photovoltaic inverter to the required reactive power;

[0023] When the maximum reactive power of the photovoltaic inverter is less than the required reactive power, adjusting the reactive regulation amount of the leading photovoltaic inverter to the maximum reactive power of the photovoltaic inverter;

[0024] Calculate the maximum regulation voltage limit based on the maximum reactive power and reactive-voltage sensitivity of the PV inverter;

[0025] Calculating the active power required for the grid connection point voltage to drop below the voltage upper limit based on the voltage over-limit degree, the maximum regulated voltage limit, and the active-voltage sensitivity of the photovoltaic inverter;

[0026] The active power regulation amount of the photovoltaic inverter is adjusted to the required active power.

[0027] When the photovoltaic inverters in the distribution network voltage management cluster are performing voltage over-limit management, the reactive power is adjusted starting from the leading photovoltaic inverter, and then the reactive power of other photovoltaic inverters in the distribution network voltage management cluster is adjusted; if the voltage over-limit is still not resolved, the active power is adjusted starting from the leading photovoltaic inverter, and then the active power of the photovoltaic inverters in the distribution network voltage management cluster is adjusted.

[0028] The technical solution adopted by the present invention to solve its technical problem is: to provide an electronic device, including a memory, a processor and a computer program stored in the memory and capable of running on the processor, and when the processor executes the computer program, the steps of the above-mentioned distribution network voltage over-limit autonomous method are implemented.

[0029] The technical solution adopted by the present invention to solve its technical problem is: providing a computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above-mentioned distribution network voltage over-limit autonomous method are implemented.

[0030] Beneficial effects

[0031] Due to the adoption of the above-mentioned technical solution, the present invention has the following advantages and positive effects compared with the existing technology: the present invention only relies on the communication and interoperability between photovoltaic inverters to complete the management of voltage over-limit. The entire process does not rely on the advance acquisition of the topology structure and network parameters of the distribution station area. The photovoltaic inverters autonomously measure and obtain the active and reactive voltage sensitivity, and autonomously cluster to participate in voltage over-limit management, thereby realizing adaptive voltage over-limit management control, improving the management timeliness and feasibility of large-scale management. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a flow chart of a distribution network voltage over-limit autonomous method according to a first embodiment of the present invention;

[0033] Figure 2 is a flow chart of a method for selecting a leading photovoltaic inverter in a first embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of a low-voltage distribution station area in the first embodiment of the present invention;

[0035] Figure 4 is a flow chart of segmented voltage sensitivity measurement in the first embodiment of the present invention;

[0036] Figure 5 Flowchart of the voltage regulation strategy in the first embodiment of the present invention. DETAILED DESCRIPTION

[0037] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0038] The first embodiment of the present invention relates to a distribution network voltage over-limit autonomous method, such as Figure 1 As shown, the following steps are included:

[0039] Step 1: Each photovoltaic inverter in the low-voltage distribution area measures its own voltage sensitivity.

[0040] like Figure 3 As shown, the low-voltage distribution substation in this embodiment includes 21 users and 9 inverters. Each PV inverter is assigned an identity code that includes both the substation and node information of the PV inverter. When a PV inverter communicates via broadcast, other PV inverters receive the broadcast information and identify the substation and location of the PV inverter by identifying the identity code.

[0041] When measuring the voltage sensitivity of the photovoltaic inverter, it can be done during the period of low daily load fluctuation, such as from 6:00 to 8:00 in the morning. At this time, the user load fluctuation is small and the measured voltage sensitivity is more accurate. At this time, each photovoltaic inverter outputs active power and reactive power quantitatively, and the active power output value of the nth photovoltaic inverter is ΔP n , the reactive power output value is ΔQ n , respectively measure the active voltage change ΔU of the node where the photovoltaic inverter is located Pn and reactive voltage change ΔU Qn , and then use formula S Pn =ΔU Pn / ΔP n , S Qn =ΔU Qn / ΔQ n Calculate the active power-voltage sensitivity S of the node where the photovoltaic inverter is located Pn and reactive-voltage sensitivity S Qn .

[0042] In order to avoid the active-voltage sensitivity S Pn and reactive-voltage sensitivity S Qn The influence of user load fluctuation on the accuracy of voltage sensitivity can be measured by multiple measurements of active-voltage sensitivity S Pn and reactive-voltage sensitivity S Qn The error is reduced by recalculating the average value. This embodiment uses the calculated average value as the active-voltage sensitivity S of the node. Pn and reactive-voltage sensitivity S Qn , take the average value of multiple measurements as the voltage sensitivity reference value for the day. When calculating the average value, the maximum and minimum values ​​need to be excluded.

[0043] In order to avoid the active-voltage sensitivity S Pn and reactive-voltage sensitivity S Qn When multiple photovoltaic inverters are operated simultaneously, the errors in the measured values ​​of active-voltage sensitivity and reactive-voltage sensitivity are too large. This embodiment can solve the problem in the following two ways: (1) the nine distributed photovoltaic inverters in the substation perform autonomous measurements in different time periods according to the voltage sensitivity measurement schedule. For example, the voltage sensitivity is measured in sequence starting from photovoltaic inverter No. 1. The measurement time for each photovoltaic inverter is 10 minutes, and the measurement is performed between 6:00 and 7:30 every day; (2) Figure 4As shown in the figure, when a photovoltaic inverter is performing measurement, it can inform other photovoltaic inverters not to perform voltage sensitivity measurement through broadcast response. After the voltage sensitivity measurement of the inverter is completed, it can inform other photovoltaic inverters that the measurement has ended through broadcast response.

[0044] Step 2: When a voltage over-limit event occurs, each photovoltaic inverter spontaneously establishes a distribution network voltage management cluster through communication interoperability, and determines the leading photovoltaic inverter of the distribution network voltage management cluster based on the location and voltage sensitivity of the photovoltaic inverter.

[0045] When establishing a voltage management cluster, it is necessary to select the leading PV inverter. The specific method is as follows:

[0046] The process of selecting the leading PV inverter is a multi-iteration process based on communication interoperability.

[0047] Assume that the branch number and node number of the PV inverter in the distribution network are (i, j), where i is the branch number and j is the node number. When any PV inverter in the distribution network detects that the voltage at the grid connection point exceeds the limit through autonomous monitoring, the PV inverter will broadcast a message carrying the voltage exceeding limit management topic through communication, and then determine in real time whether the topic has been subscribed by other PV inverters. The method for subscribing to the voltage exceeding limit topic is:

[0048] Assume that after the photovoltaic inverter (m, n) monitors the voltage over-limit management topic released by the photovoltaic inverter (i, j), it will actively set its own voltage over-limit degree index M mn The voltage over-limit index M of the monitored photovoltaic inverter (i, j) ij The voltage over-limit index is the ratio of the effective value of the line voltage at the photovoltaic inverter grid connection point to the effective value of the baseline line voltage. mn ≤M ij , then PV inverter (i, j) subscribes to the voltage over-limit management topic of PV inverter (m, n). At this time, PV inverter (i, j) stops publishing its own topic and confirms that it is proxied by PV inverter (m, n). PV inverter (i, j) communication switches to passive listening mode. mn >M ij , then photovoltaic inverter (i, j) becomes the agent of photovoltaic inverter (m, n). At this time, photovoltaic inverter (m, n) stops publishing its own topic, and photovoltaic inverter (m, n) communication switches to passive listening mode.

[0049] Repeat the above steps until it is confirmed that the photovoltaic inverter (l, k) becomes the agent of all the topics that publish photovoltaic inverter voltage over-limit management. Then the photovoltaic inverter (l, k) becomes the leading photovoltaic inverter. The leading photovoltaic inverter initiates a voltage over-limit management group invitation to other proxy photovoltaic inverters, and controls the photovoltaic inverters that join the management cluster to collaboratively complete the voltage over-limit management task.

[0050] In this step, the nine PV inverters continuously monitor node voltages. When PV inverters 4-9 detect a voltage over-limit condition, they initiate the establishment of a voltage management cluster topic via a broadcast signal. Simultaneously, PV inverters 4-9 in the same area respond to the broadcast signal with a handshake. The nodes belonging to PV inverters 1-3 do not experience a voltage over-limit condition, indicating a minor voltage over-limit condition and therefore do not participate in this management. However, the nodes belonging to PV inverters 4-9 do experience a voltage over-limit condition and participate in this voltage over-limit management.

[0051] After a handshake process involving topic publishing and subscription, PV inverter No. 7 in the voltage management cluster was successfully selected as the lead inverter, as it was the PV inverter belonging to the grid-connected node with the highest voltage sensitivity and the most severe voltage overlimit. This selection of the lead inverter was unique, and the other PV inverters in the voltage management cluster were designated as slaves. After the voltage overlimit was reduced to the required value, the lead inverter initiated a signal to disband the voltage overlimit group, completing the voltage overlimit management task.

[0052] Step 3: According to the voltage over-limit situation, the leading photovoltaic inverter controls the output reactive power and active power according to its own voltage sensitivity, and notifies the other photovoltaic inverters in the distribution network voltage management cluster of the management results. If the management effect of the leading photovoltaic inverter cannot meet the requirements, the other photovoltaic inverters in the distribution network voltage management cluster will participate in this voltage over-limit management and divide the voltage management responsibilities according to their respective voltage sensitivities.

[0053] like Figure 5 As shown, the voltage regulation strategy of this embodiment is to first measure the node voltages of the nodes to which photovoltaic inverters 1-9 belong, which are U1, U2, U3, U4, U5, U6, U7, U8, and U9. At this time, the voltages U4, U5, U6, U7, U8, and U9 are greater than the voltage upper limit U max When the voltage limit in the substation is usually set to 1.07U N , using ΔU n =U n -U max Calculate the voltage difference and then use the formula ΔQ PVn =ΔU n / S QnThe calculation results in the node voltage dropping to the upper voltage limit U max The following reactive power ΔQ is required PVn .

[0054] Compare the required reactive power ΔQ PVn and the maximum reactive power Q of each photovoltaic inverter PVmax , if ΔQ PVn <Q PVmax , then the voltage over-limit problem can be solved by adjusting the reactive power of the distributed photovoltaic inverter. At this time, the reactive power adjustment amount of the photovoltaic inverter is set to ΔQ PVn , if ΔQ PVn >Q PVmax , then it is necessary to appropriately reduce the active power of the photovoltaic inverter. At this time, the reactive power regulation of the photovoltaic inverter is set to Q PVmax At the same time, it is also necessary to reduce the active power of the photovoltaic inverter, using the formula ΔU Qmax =Q PVmax ·S Qn The maximum voltage limit for regulating the reactive power of the photovoltaic inverter is calculated using the formula ΔU n '=U n -ΔU Qmax -U max With ΔP PVn =ΔU n ' / S Pn Calculate the voltage drop of the node to the upper voltage limit U max The following reactive power ΔP is required PVn , the active power regulation of the photovoltaic inverter at the node where the voltage over-limit problem cannot be solved by regulating reactive power alone is set to ΔP PVn .

[0055] The order of voltage over-limit control is to give priority to the use of photovoltaic inverter reactive voltage regulation, starting with photovoltaic inverter No. 7, the leading inverter, to adjust the reactive power, and then adjust the reactive power of the slave photovoltaic inverters; if the voltage over-limit problem is still not solved, start with photovoltaic inverter No. 7, the leading inverter, to adjust the active power, and then adjust the active power of the slave photovoltaic inverters.

[0056] It is not difficult to find that this implementation method can quickly and efficiently complete the management of the voltage over-limit problem in the substation by relying solely on the communication and interoperability between photovoltaic inverters. The entire process does not rely on the upper control center, and the required data requirements are small, which reduces the workload before voltage management and improves the real-time performance of the substation voltage over-limit management. In addition, the management task is actively initiated by the photovoltaic inverter. Compared with the traditional architecture that relies on centralized and passive management by the upper control center, it presents a decentralized, adaptive and flexible architecture, which has better adaptability to the voltage over-limit management scenario in complex substations.

[0057] A second embodiment of the present invention relates to an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the distribution network voltage over-limit autonomous method of the first embodiment are implemented.

[0058] A third embodiment of the present invention relates to a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the distribution network voltage over-limit autonomous method of the first embodiment are implemented.

[0059] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage and optical storage, etc.) that contain computer-usable program code.

[0060] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0061] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction method, which is implemented in the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0062] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1A step that specifies a function in one or more boxes.

[0063] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A distribution network voltage over-limit autonomous method, characterized in that: The following steps are involved: Each photovoltaic inverter in the low-voltage distribution area measures its own voltage sensitivity; When a voltage over-limit event occurs, each photovoltaic inverter spontaneously establishes a distribution network voltage management cluster through communication and interoperability, and determines the leading photovoltaic inverter of the distribution network voltage management cluster based on the location and voltage sensitivity of the photovoltaic inverter; According to the voltage over-limit situation, the photovoltaic inverters in the distribution network voltage management cluster control the output reactive power and active power according to their own voltage sensitivity to complete the voltage over-limit management.

2. The distribution network voltage over-limit autonomous method according to claim 1, characterized in that: Each photovoltaic inverter within the low-voltage distribution station area measures its own voltage sensitivity. Specifically, when the daily load fluctuation is less than a preset value, each photovoltaic inverter outputs a quantitative amount of active power and reactive power, and measures the active voltage change and reactive voltage change of the node where the photovoltaic inverter is located. The active-voltage sensitivity of the photovoltaic inverter is determined based on the active voltage change and the active power output value, and the reactive-voltage sensitivity of the photovoltaic inverter is determined based on the reactive voltage change and the reactive power output value.

3. The distribution network voltage over-limit autonomous method according to claim 2, characterized in that: The active-voltage sensitivity is determined by S Pn =ΔU Pn / ΔP n The reactive-voltage sensitivity is calculated by S Qn =ΔU Qn / ΔQ n Calculated, where S Pn and S Qn are the active-voltage sensitivity and reactive-voltage sensitivity of the n-th photovoltaic inverter, ΔU Pn and ΔU Qn are the active voltage change and reactive voltage change of the node where the nth photovoltaic inverter is located, ΔP n and ΔQ n is the active power output value and reactive power output value of the nth photovoltaic inverter.

4. The distribution network voltage over-limit autonomous method according to claim 2, characterized in that: When each photovoltaic inverter performs quantitative output of active power and reactive power, each photovoltaic inverter performs quantitative output of active power and reactive power in time periods according to the voltage sensitivity measurement plan schedule.

5. The distribution network voltage over-limit autonomous method according to claim 2, characterized in that: When each photovoltaic inverter performs quantitative output of active power and reactive power respectively, when a photovoltaic inverter is quantitatively outputting active power and reactive power, it notifies other photovoltaic inverters not to perform voltage sensitivity measurement through a broadcast response method. When the photovoltaic inverter completes the voltage sensitivity measurement, it notifies other photovoltaic inverters that the measurement has ended through a broadcast response method.

6. The distribution network voltage over-limit autonomous method according to claim 1, characterized in that: The photovoltaic inverters spontaneously establish a voltage management cluster for this distribution network through communication and interoperability. Specifically, the photovoltaic inverters at the grid-connected node with the most serious voltage over-limit initiate a request to establish a voltage management cluster through a broadcast signal. The photovoltaic inverters respond and handshake through a broadcast signal, and the voltage management cluster is established. After receiving the request to establish a voltage management cluster, other photovoltaic inverters decide whether to join the voltage management cluster based on the voltage exceeding the limit at the grid connection point.

7. The distribution network voltage over-limit autonomous method according to claim 6, characterized in that: The leading photovoltaic inverter is the photovoltaic inverter at the grid-connected node with the highest voltage sensitivity and the most serious voltage over-limit degree.

8. The distribution network voltage over-limit autonomous method according to claim 7, characterized in that: The leading photovoltaic inverter is selected in the following manner: When any PV inverter in the substation discovers that the voltage at the grid connection point exceeds the limit through autonomous monitoring, the PV inverter (i, j) will broadcast a message carrying the topic of voltage exceeding the limit through communication. When the photovoltaic inverter (m, n) monitors the voltage over-limit management topic released by the photovoltaic inverter (i, j), it will automatically set its own voltage over-limit index M mn The voltage over-limit index M of the monitored photovoltaic inverter (i, j) ij For comparison, if the voltage exceeds the limit level indicator M mn Less than or equal to the voltage over-limit index M of the monitored photovoltaic inverter (i, j) ij , the photovoltaic inverter (i, j) stops publishing its own topic and subscribes to the voltage over-limit management topic of the photovoltaic inverter (m, n), confirming that it is proxied by the photovoltaic inverter (m, n), and the photovoltaic inverter (i, j) communication switches to passive monitoring mode; if its own voltage over-limit degree indicator M mn Greater than the voltage over-limit index M of the monitored photovoltaic inverter (i, j) ij , then PV inverter (i, j) becomes the agent of PV inverter (m, n), PV inverter (m, n) stops publishing its own topic, and PV inverter (m, n) communication switches to passive listening mode; Repeat the above steps until it is confirmed that the photovoltaic inverter (l, k) becomes the agent of all topics that publish photovoltaic inverter voltage over-limit management, and the photovoltaic inverter (l, k) becomes the leading photovoltaic inverter.

9. The distribution network voltage over-limit autonomous method according to claim 1, characterized in that: According to the voltage over-limit situation, the photovoltaic inverters in the distribution network voltage management cluster control the output reactive power and active power according to their own voltage sensitivity to complete the voltage over-limit management, specifically as follows: Calculate the voltage limit level based on the current voltage of the grid-connected node and the voltage upper limit of the grid-connected node; Determine the reactive power required for the grid connection point voltage to drop below the voltage upper limit based on the reactive-voltage sensitivity of each photovoltaic inverter and the voltage over-limit degree; When the maximum reactive power of the photovoltaic inverter is greater than or equal to the required reactive power, adjusting the reactive regulation amount of the leading photovoltaic inverter to the required reactive power; When the maximum reactive power of the photovoltaic inverter is less than the required reactive power, adjusting the reactive regulation amount of the leading photovoltaic inverter to the maximum reactive power of the photovoltaic inverter; Calculate the maximum regulation voltage limit based on the maximum reactive power and reactive-voltage sensitivity of the PV inverter; Calculating the active power required for the grid connection point voltage to drop below the voltage upper limit based on the voltage over-limit degree, the maximum regulated voltage limit, and the active-voltage sensitivity of the photovoltaic inverter; The active power regulation amount of the photovoltaic inverter is adjusted to the required active power.

10. The distribution network voltage over-limit autonomous method according to claim 9, characterized in that: When the photovoltaic inverters in the distribution network voltage management cluster are performing voltage over-limit management, the reactive power is adjusted starting with the leading photovoltaic inverter, and then the reactive power of other photovoltaic inverters in the distribution network voltage management cluster is adjusted; If the voltage limit problem is still not resolved, the active power is adjusted starting from the leading photovoltaic inverter, and then the active power of the photovoltaic inverters in the distribution network voltage management cluster is adjusted.

11. 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 distribution network voltage over-limit autonomous method as described in any one of claims 1-10 are implemented.

12. 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 distribution network voltage over-limit autonomous method as claimed in any one of claims 1 to 10 are implemented.

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