Grid Voltage Control Method, Device, Equipment and Medium with Distributed Photovoltaic

Abstract

The present invention discloses a grid voltage control method, device, equipment and medium including distributed photovoltaic. The method includes: obtaining current node data of multiple grid-connected nodes in a distribution network; in the grid dispatching layer, configuring and optimizing the reactive power capacity of multiple grid-connected nodes according to the current node data and a preset voltage sensitivity matrix to obtain the photovoltaic capacity of each grid-connected node; in the grid application layer, predicting the power adjustment amount of each grid-connected node at a future target time according to the photovoltaic capacity and a preset grid state space equation; sending a voltage control instruction carrying the power adjustment amount to a grid-connected inverter, and the grid-connected inverter is used to execute the voltage control instruction to adjust the grid voltage. The present invention solves the problem of reactive power margin differentiation between nodes by controlling the reactive power adjustment margin of each grid-connected node, and further considers the individual differences of distributed photovoltaics in a hierarchical control manner to improve the voltage control effect.

Description

Technical Field

[0001] The present invention relates to the technical field of grid voltage control, and particularly to a grid voltage control method, device, equipment and medium for a power grid with distributed photovoltaic power generation. Background Art

[0002] Distributed photovoltaic power generation increases the complexity of the operation and control of the distribution network. Under the background of large-scale photovoltaic access, it is difficult to predict the output of distributed photovoltaic power generation related to meteorology. The drastic fluctuation of uncertain power leads to reverse power flow and voltage mutation in the distribution network, and the voltage of the regional power grid is extremely vulnerable to the active or reactive power output of photovoltaic power generation, resulting in frequent problems of voltage over-limit and voltage fluctuation in a short time.

[0003] At present, photovoltaic inverters have the ability of rapid reactive power compensation, and the utilization of the remaining capacity can reduce the action frequency and cost of system reactive power compensation. However, the traditional reactive power droop control method based on photovoltaic inverters is mainly for centralized photovoltaic power stations, and it cannot solve the problem of reactive power margin differentiation existing in distributed photovoltaic power generation. Therefore, in order to better utilize the dynamic regulation ability after the grid connection of distributed photovoltaic power generation, there is an urgent need for a grid connection voltage control method for a power grid with distributed photovoltaic power generation. Summary of the Invention

[0004] The present invention provides a grid voltage control method, device, equipment and storage medium for a power grid with distributed photovoltaic power generation to solve the technical problem that the current voltage control method cannot cope with the reactive power margin differentiation existing in distributed photovoltaic power generation.

[0005] To solve the above technical problem, in a first aspect, the present invention provides a grid voltage control method for a power grid with distributed photovoltaic power generation, including:

[0006] Obtain the current node data of multiple grid-connected nodes in the distribution network, where the grid-connected nodes are distributed photovoltaic power generations grid-connected to the distribution network, and the current node data includes node voltage, first active power and first reactive power;

[0007] At the grid dispatching layer, configure and optimize the reactive power capacity of multiple grid-connected nodes according to the current node data and a preset voltage sensitivity matrix to obtain the photovoltaic capacity of each grid-connected node;

[0008] At the grid application layer, predict the power adjustment amount of each grid-connected node at a future target time according to the photovoltaic capacity and a preset grid state space equation, where the power adjustment amount includes second active power and second reactive power;

[0009] Send a voltage control instruction carrying the power adjustment amount to the grid-connected inverter, and the grid-connected inverter is used to execute the voltage control instruction to adjust the grid voltage.

[0010] Preferably, at the grid dispatching layer, according to the current node data and the preset voltage sensitivity matrix, the reactive power capacity of multiple grid-connected nodes is configured and optimized to obtain the photovoltaic capacity of each grid-connected node, including:

[0011] At the grid dispatching layer, for each grid-connected node, according to the preset voltage sensitivity matrix, calculate the node voltage threshold range of the grid-connected node;

[0012] If the reactive power capacity of the grid-connected node does not meet the preset grid conditions, then reduce the active power capacity of the grid-connected node until the current node data of the grid-connected node meets the preset constraint conditions to obtain the photovoltaic capacity.

[0013] Preferably, according to the preset voltage sensitivity matrix, calculating the node voltage threshold range of the grid-connected node includes:

[0014] According to the preset voltage sensitivity matrix, calculate the node voltage change of the grid-connected node;

[0015] Perform an addition operation on the node voltage change and the preset voltage reference value to obtain the node voltage threshold of the grid-connected node;

[0016] According to the node voltage threshold and the preset deviation range, determine the node voltage threshold range of the grid-connected node.

[0017] Preferably, before, at the grid dispatching layer, according to the current node data and the preset voltage sensitivity matrix, the reactive power capacity of multiple grid-connected nodes is configured and optimized to obtain the photovoltaic capacity of each grid-connected node, further including:

[0018] At the grid dispatching layer, according to the node information and line information of the distribution network, construct the steady-state power flow equation of the power system in polar coordinates;

[0019] Modify and perform matrix transformation on the steady-state power flow equation of the power system to obtain the preset voltage sensitivity matrix, and the preset voltage sensitivity matrix is:

[0020]

[0021] Among them, Δθ is the phase angle increment of the grid-connected node, ΔU is the voltage increment of the grid-connected node, ΔP is the active power increment of the grid-connected node, ΔQ is the reactive power increment of the grid-connected node, and S1, S2, S3, and S4 are voltage sensitivity coefficients.

[0022] Preferably, at the grid application layer, according to the photovoltaic capacity and the preset grid state space equation, predict the power regulation amount of each grid-connected node at the future target time, including:

[0023] At the grid application layer, according to the photovoltaic capacity, calculate the voltage deviation weight of each grid-connected node;

[0024] Predict the target node data of multiple grid-connected nodes at a future target time according to the preset power grid state space equation;

[0025] Use the interior point method to iterate the target node data of multiple grid-connected nodes according to the voltage deviation weight until the deviation value between the node voltage in the target node data and the preset voltage reference reaches the minimum value, and obtain the power adjustment amount of each grid-connected node at the future target time.

[0026] Preferably, calculate the voltage deviation weight of each grid-connected node according to the photovoltaic capacity, including:

[0027] Use the preset weight calculation formula to calculate the voltage deviation weight of each grid-connected node according to the photovoltaic capacity. The preset weight calculation formula is:

[0028]

[0029] ε j represents the voltage deviation weight of the jth grid-connected node, S PV，j represents the photovoltaic capacity of the jth grid-connected node, and m represents the total number of grid-connected nodes.

[0030] Preferably, use the interior point method to iterate the target node data of multiple grid-connected nodes according to the voltage deviation weight until the deviation value between the node voltage in the target node data and the preset voltage reference reaches the minimum value, and obtain the power adjustment amount of each grid-connected node at the future target time, including:

[0031] Use the interior point method to update the target node data of the grid-connected nodes according to the voltage deviation weight to obtain new target node data;

[0032] Based on the deviation control function, calculate the deviation value between the node voltage in the new target node data and the preset voltage reference value according to the new target node data;

[0033] Take the active power and reactive power in the new target node data corresponding to the node voltage with the minimum deviation value as the power adjustment amount.

[0034] In a second aspect, the present invention provides a power grid voltage control device with distributed photovoltaics, including:

[0035] An acquisition module for acquiring the current node data of multiple grid-connected nodes in the distribution network. The grid-connected nodes are distributed photovoltaics connected to the distribution network, and the current node data includes node voltage, first active power, and first reactive power;

[0036] An optimization module, which is used to configure and optimize the reactive power capacity of multiple grid-connected nodes according to the current node data and a preset voltage sensitivity matrix at the grid dispatching layer, so as to obtain the photovoltaic capacity of each grid-connected node;

[0037] A prediction module, which is used to predict the power adjustment amount of each grid-connected node at a future target time according to the photovoltaic capacity and a preset grid state space equation at the grid application layer, and the power adjustment amount includes a second active power and a second reactive power;

[0038] A sending module, which is used to send a voltage control instruction carrying the power adjustment amount to a grid-connected inverter, and the grid-connected inverter is used to execute the voltage control instruction to adjust the grid voltage.

[0039] In a third aspect, the present invention provides an electronic device, including a processor and a memory, where the memory is used to store a computer program, and when the computer program is executed by the processor, it implements the grid voltage control method with distributed photovoltaic as described in the first aspect.

[0040] In a fourth aspect, the present invention provides a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, it implements the grid voltage control method with distributed photovoltaic as described in the first aspect.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] The present invention configures and optimizes the reactive power capacity of multiple grid-connected nodes according to the current node data and a preset voltage sensitivity matrix at the grid dispatching layer to obtain the photovoltaic capacity of each grid-connected node, so as to control the reactive power regulation margin of each grid-connected node, thereby solving the problem of different reactive power margins between nodes and ensuring that the voltage of the grid-connected nodes does not exceed the limit and has sufficient reactive power regulation margin; and at the grid application layer, according to the photovoltaic capacity and a preset grid state space equation, predicts the power adjustment amount of each grid-connected node at a future target time, and sends a voltage control instruction carrying the power adjustment amount to a grid-connected inverter to achieve hierarchical control of the grid voltage, further considering the individual differences of distributed photovoltaics and improving the voltage control effect. Description of the Drawings

[0043] Figure 1 It is a schematic flowchart of the grid voltage control method with distributed photovoltaic shown in the embodiment of the present invention;

[0044] Figure 2 It is a schematic structural diagram of the grid voltage control device with distributed photovoltaic shown in the embodiment of the present invention;

[0045] Figure 3 It is a schematic structural diagram of the computer device shown in the embodiment of the present invention. Detailed Embodiments

[0046] Next, in combination with the accompanying drawings in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0047] Please refer to Figure 1 , Figure 1 which is a schematic flowchart of a grid voltage control method with distributed photovoltaic provided by an embodiment of the present invention. The method in the embodiment of the present invention can be applied to computer devices, including but not limited to devices such as laptop computers, tablet computers, desktop computers, physical servers, and cloud servers. As Figure 1 shown, the grid voltage control method with distributed photovoltaic in this embodiment includes steps S101 to S104, which are described in detail as follows:

[0048] Step S101, obtain the current node data of multiple grid-connected nodes in the distribution network. The grid-connected nodes are distributed photovoltaics grid-connected to the distribution network, and the current node data includes node voltage, first active power, and first reactive power.

[0049] In this step, the distribution network includes multiple distributed photovoltaics connected to the grid, and each distributed photovoltaic is used as a grid-connected node of the distribution network. Due to the difference in reactive power margin of distributed photovoltaics, the power output of each distributed photovoltaic to the distribution network is determined in this embodiment to perform different degrees of power output for the reactive power margins of different distributed photovoltaics.

[0050] Step S102, at the grid dispatching layer, according to the current node data and a preset voltage sensitivity matrix, optimize the configuration of the reactive power capacity of multiple grid-connected nodes to obtain the photovoltaic capacity of each grid-connected node.

[0051] In this step, the preset voltage sensitivity matrix is a matrix representing the sensitivity of voltage with respect to active power and reactive power. Each distributed photovoltaic has configuration information of reactive power capacity. To ensure that the grid-connected voltage does not exceed the limit and the node reactive power regulation margin can meet the requirements of grid operation, the reactive power capacity of grid-connected nodes is dynamically configured and optimized in real time, where the photovoltaic capacity includes active power capacity and reactive power capacity.

[0052] In one embodiment, step S102 includes:

[0053] At the grid dispatching layer, for each grid-connected node, calculate the node voltage threshold range of the grid-connected node according to the preset voltage sensitivity matrix;

[0054] If the reactive power capacity of the grid-connected node does not meet the preset grid conditions, the active power capacity of the grid-connected node is reduced until the current node data of the grid-connected node meets the preset constraint conditions, and the photovoltaic capacity is obtained.

[0055] In this embodiment, according to the grid node voltage sensitivity matrix, the active power output of distributed photovoltaics is optimized to ensure that the voltage at the photovoltaic grid connection point does not exceed the limit. If the reactive power regulation margin of the grid-connected node cannot meet the preset grid requirements during a certain period, the active power capacity is reduced to provide additional reactive power capacity for the grid-connected node, which can be expressed as:

[0056]

[0057]

[0058] m is the total number of distributed photovoltaics, is the reactive power regulation amount, V PCC is the current node voltage, P is the active power capacity, Q is the reactive power capacity, and S represents the photovoltaic capacity.

[0059] Optionally, the construction process of the preset voltage sensitivity matrix includes: at the grid dispatching layer, according to the node information and line information of the distribution network, constructing a steady-state power flow equation of the power system in polar coordinates; correcting and performing matrix transformation on the steady-state power flow equation of the power system to obtain the preset voltage sensitivity matrix.

[0060] Optionally, the steady-state power flow equation of the power system in polar coordinate form is constructed by the Newton-Raphson method:

[0061]

[0062]

[0063] G ij represents the conductance matrix, B ij represents the susceptance matrix, P i represents the active power, Q i represents the reactive power, U i represents the node voltage, θ ij represents the phase angle difference.

[0064] Furthermore, the correction equation represented in matrix form is derived as:

[0065]

[0066] Δθ is the phase angle increment of the grid-connected node, ΔU is the voltage increment of the grid-connected node, ΔP is the active power increment of the grid-connected node, and ΔQ is the reactive power increment of the grid-connected node.

[0067] After performing matrix transformation on the above corrected equation, a preset voltage sensitivity matrix is obtained:

[0068]

[0069] S1, S2, S3, and S4 are voltage sensitivity coefficients.

[0070] Optionally, the calculation process of the node voltage threshold range includes: calculating the change in the node voltage of the grid-connected node according to the preset voltage sensitivity matrix; performing an addition operation on the change in the node voltage and a preset voltage reference value to obtain the node voltage threshold of the grid-connected node; and determining the node voltage threshold range of the grid-connected node according to the node voltage threshold and a preset deviation range.

[0071] In this optional embodiment, by screening the voltage sensitivity coefficients S3 and S4, the change in the node voltage is defined as:

[0072] ΔV PCC =S PCC,P ΔP+S PCC,Q ΔQ;

[0073] where S PCC,P represents the sensitivity of the node voltage with respect to the active power, and S PCC,Q represents the sensitivity of the node voltage with respect to the reactive power.

[0074] The calculated node voltage threshold is:

[0075] V PCC =V PCC,0 +ΔV PCC ;

[0076] V PCC,0 is the reference value of the node voltage.

[0077] Combined with the preset deviation range, the node voltage threshold range is obtained: V PCC,min ≤V PCC ≤V PCC,max .

[0078] Step S103, in the power grid application layer, according to the photovoltaic capacity and the preset power grid state space equation, predict the power regulation amount of each grid-connected node at a future target time, where the power regulation amount includes a second active power and a second reactive power.

[0079] In this step, the power output of each grid-connected node has a certain adjustment range, so it is possible to select a power combination that meets the actual demand by adjusting the power output of each grid-connected node. The preset power grid state space equation represents the state relationship between the node voltage and the reactive power of multiple grid-connected nodes in the distribution network at a future target time.

[0080] In one embodiment, step S103 includes:

[0081] In the power grid application layer, according to the photovoltaic capacity, calculate the voltage deviation weight of each grid-connected node;

[0082] According to the preset power grid state space equation, predict the target node data of multiple grid-connected nodes at the future target time;

[0083] Using the interior point method, according to the voltage deviation weight, iterate the target node data of multiple grid-connected nodes until the deviation value between the node voltage in the target node data and the preset voltage reference amount reaches the minimum value, and obtain the power adjustment amount of each grid-connected node at the future target time.

[0084] In this embodiment, optionally, the calculation process of the voltage deviation weight includes: using a preset weight calculation formula, according to the photovoltaic capacity, calculate the voltage deviation weight of each grid-connected node, and the preset weight calculation formula is:

[0085]

[0086] ε j represents the voltage deviation weight of the jth grid-connected node, S PV，j represents the photovoltaic capacity of the jth grid-connected node, and m represents the total number of grid-connected nodes.

[0087] Optionally, the preset system state space equation is:

[0088] x(k + 1) = Ax(k) + Bu(k) + Gw(k);

[0089] y(k) = Cx(k);

[0090] x(k) is the state quantity; u(k) is the state quantity, w(k) is the disturbance quantity; y(k) is the output quantity; A, B, C, D, and G are preset coefficient matrices.

[0091] Among them, x(k) specifically represents the reactive power of multiple grid-connected nodes, for example:

[0092]

[0093] y(k) specifically represents the node voltage of multiple grid-connected nodes, for example:

[0094]

[0095] Optionally, the implementation process of the interior point method includes: updating the target node data of the grid-connected node according to the voltage deviation weight to obtain new target node data; calculating the deviation value between the node voltage in the new target node data and the preset voltage reference value based on the deviation control function; using the active power and reactive power in the new target node data corresponding to the node voltage with the minimum deviation value as the power adjustment amount.

[0096] In this optional embodiment, through the above Y k and X k the node voltage set and the reactive power set are determined, and the deviation value is calculated according to the deviation control function. The deviation control function is:

[0097]

[0098] When J(Y k ,X k ) = min J(Y k ,X k ), the deviation value between the node voltage at time k and the preset voltage reference value is the smallest, then the reactive power corresponding to this node voltage is used as the second reactive power, and then the second active power is calculated by combining the second reactive power with the photovoltaic capacity to obtain the power adjustment amount.

[0099] Step S104, sending the voltage control command carrying the power adjustment amount to the grid-connected inverter, and the grid-connected inverter is used to execute the voltage control command to adjust the grid voltage.

[0100] In this step, the grid-connected inverter adjusts the active power output and reactive power output of each distributed photovoltaic according to the voltage control command to achieve the purpose of adjusting the grid voltage.

[0101] In order to execute the grid voltage control method with distributed photovoltaics corresponding to the above method embodiment to achieve the corresponding functions and technical effects. Refer to Figure 2 , Figure 2 shows the structural block diagram of a grid voltage control device with distributed photovoltaics provided by an embodiment of the present invention. For the sake of convenience of description, only the parts related to this embodiment are shown. The grid voltage control device with distributed photovoltaics provided by the embodiment of the present invention includes:

[0102] An acquisition module 201, configured to acquire the current node data of multiple grid-connected nodes in the distribution network, where the grid-connected nodes are distributed photovoltaics grid-connected to the distribution network, and the current node data includes node voltage, first active power, and first reactive power;

[0103] Optimization module 202, which is used to configure and optimize the reactive power capacity of multiple grid-connected nodes according to the current node data and the preset voltage sensitivity matrix at the grid dispatching layer, so as to obtain the photovoltaic capacity of each grid-connected node;

[0104] Prediction module 203, which is used to predict the power adjustment amount of each grid-connected node at a future target time according to the photovoltaic capacity and the preset grid state space equation at the grid application layer, and the power adjustment amount includes the second active power and the second reactive power;

[0105] Sending module 204, which is used to send a voltage control instruction carrying the power adjustment amount to the grid-connected inverter, and the grid-connected inverter is used to execute the voltage control instruction to adjust the grid voltage.

[0106] In one embodiment, the optimization module 202 includes:

[0107] The first calculation unit is used to calculate the node voltage threshold range of each grid-connected node according to the preset voltage sensitivity matrix at the grid dispatching layer;

[0108] The reduction unit is used to reduce the active power capacity of the grid-connected node if the reactive power capacity of the grid-connected node does not meet the preset grid conditions until the current node data of the grid-connected node meets the preset constraint conditions, so as to obtain the photovoltaic capacity.

[0109] In one embodiment, the first calculation unit is specifically used for:

[0110] Calculate the node voltage change amount of the grid-connected node according to the preset voltage sensitivity matrix;

[0111] Perform an addition operation on the node voltage change amount and the preset voltage reference value to obtain the node voltage threshold of the grid-connected node;

[0112] Determine the node voltage threshold range of the grid-connected node according to the node voltage threshold and the preset deviation range.

[0113] In one embodiment, the device further includes:

[0114] The construction module is used to construct the steady-state power flow equation of the power system in polar coordinates according to the node information and line information of the distribution network at the grid dispatching layer;

[0115] The processing module is used to correct and perform matrix transformation on the steady-state power flow equation of the power system to obtain the preset voltage sensitivity matrix, and the preset voltage sensitivity matrix is:

[0116]

[0117] Among them, Δθ is the phase angle increment of the grid-connected node, ΔU is the voltage increment of the grid-connected node, ΔP is the active power increment of the grid-connected node, ΔQ is the reactive power increment of the grid-connected node, and S1, S2, S3, and S4 are voltage sensitivity coefficients.

[0118] In one embodiment, the prediction module 203 includes:

[0119] A second calculation unit, configured to calculate the voltage deviation weight of each grid-connected node according to the photovoltaic capacity at the grid application layer;

[0120] A prediction unit, configured to predict the target node data of multiple grid-connected nodes at the future target time according to the preset grid state space equation;

[0121] An iteration unit, configured to use the interior point method to iterate the target node data of multiple grid-connected nodes according to the voltage deviation weight until the deviation value between the node voltage in the target node data and the preset voltage reference amount reaches the minimum value, and obtain the power adjustment amount of each grid-connected node at the future target time.

[0122] In one embodiment, the second calculation unit is specifically configured to:

[0123] Use a preset weight calculation formula to calculate the voltage deviation weight of each grid-connected node according to the photovoltaic capacity, and the preset weight calculation formula is:

[0124]

[0125] ε j represents the voltage deviation weight of the jth grid-connected node, S PV，j represents the photovoltaic capacity of the jth grid-connected node, and m represents the total number of grid-connected nodes.

[0126] In one embodiment, the iteration unit is specifically configured to:

[0127] Use the interior point method to update the target node data of the grid-connected node according to the voltage deviation weight to obtain new target node data;

[0128] Based on the deviation control function, calculate the deviation value between the node voltage in the new target node data and the preset voltage reference value according to the new target node data;

[0129] Use the active power and reactive power in the new target node data corresponding to the node voltage with the minimum deviation value as the power adjustment amount.

[0130] The above grid voltage control device with distributed PV can implement the grid voltage control method with distributed PV in the above method embodiment. The optional items in the above method embodiment are also applicable to this embodiment and will not be elaborated here. The remaining content of the embodiment of the present invention can refer to the content of the above method embodiment and will not be repeated in this embodiment.

[0131] Figure 3 It is a schematic structural diagram of a computer device provided by an embodiment of the present invention. As Figure 3 shown, the computer device 3 in this embodiment includes: at least one processor 30 ( Figure 3 only one is shown in the figure), a processor, a memory 31, and a computer program 32 stored in the memory 31 and executable on the at least one processor 30. When the processor 30 executes the computer program 32, it implements the steps in any of the above method embodiments.

[0132] The computer device 3 may be a computing device such as a smart phone, a tablet computer, a desktop computer, and a cloud server. The computer device may include but is not limited to the processor 30 and the memory 31. Those skilled in the art can understand that Figure 3 this is only an example of the computer device 3 and does not constitute a limitation on the computer device 3. It may include more or fewer components than those shown in the figure, or combine some components, or different components. For example, it may also include input / output devices, network access devices, etc.

[0133] The so-called processor 30 may be a central processing unit (CPU). The processor 30 may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0134] In some embodiments, the memory 31 may be an internal storage unit of the computer device 3, such as the hard disk or memory of the computer device 3. In other embodiments, the memory 31 may also be an external storage device of the computer device 3, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. equipped on the computer device 3. Further, the memory 31 may also include both the internal storage unit and the external storage device of the computer device 3. The memory 31 is used to store an operating system, application programs, a BootLoader, data, and other programs, such as the program code of the computer program. The memory 31 may also be used to temporarily store data that has been output or is to be output.

[0135] In addition, an embodiment of the present invention further provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the steps in any of the above method embodiments are implemented.

[0136] An embodiment of the present invention provides a computer program product, and when the computer program product runs on a computer device, the computer device is caused to execute the steps in each of the above method embodiments.

[0137] In several embodiments provided by the present invention, it can be understood that each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the module, the program segment, or the part of code contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in an order different from that marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved.

[0138] When the above-mentioned functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or a part of this technical solution can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0139] The specific embodiments described above further elaborate on the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. It is particularly pointed out that for those skilled in the art, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A grid voltage control method with distributed photovoltaic power generation, characterized in that, Including: Obtain the current node data of multiple grid-connected nodes in the distribution network. The grid-connected nodes are distributed photovoltaics grid-connected to the distribution network, and the current node data includes node voltage, first active power, and first reactive power. At the grid dispatching layer, according to the current node data and a preset voltage sensitivity matrix, optimize the reactive power capacity configuration of multiple grid-connected nodes to obtain the photovoltaic capacity of each grid-connected node. Among them, the preset voltage sensitivity matrix is a matrix representing the sensitivity of voltage with respect to active power and reactive power. At the grid application layer, according to the photovoltaic capacity and a preset grid state space equation, predict the power adjustment amount of each grid-connected node at a future target time. The power adjustment amount includes second active power and second reactive power. Among them, the preset grid state space equation is a state relationship between the node voltage and reactive power of multiple grid-connected nodes in the distribution network at a future target time. Send a voltage control instruction carrying the power adjustment amount to the grid-connected inverter, and the grid-connected inverter is used to execute the voltage control instruction to adjust the grid voltage.

2. The grid voltage control method with distributed photovoltaic as claimed in claim 1, wherein The step of, at the grid dispatching layer, according to the current node data and a preset voltage sensitivity matrix, optimizing the reactive power capacity configuration of multiple grid-connected nodes to obtain the photovoltaic capacity of each grid-connected node includes: At the grid dispatching layer, for each grid-connected node, calculate the node voltage threshold range of the grid-connected node according to the preset voltage sensitivity matrix. If the reactive power capacity of the grid-connected node does not meet the preset grid conditions, reduce the active power capacity of the grid-connected node until the current node data of the grid-connected node meets the preset constraint conditions to obtain the photovoltaic capacity.

3. The grid voltage control method for distributed photovoltaic as claimed in claim 2, wherein The step of calculating the node voltage threshold range of the grid-connected node according to the preset voltage sensitivity matrix includes: Calculate the node voltage change amount of the grid-connected node according to the preset voltage sensitivity matrix. Perform an addition operation on the node voltage change amount and a preset voltage reference value to obtain the node voltage threshold of the grid-connected node. Determine the node voltage threshold range of the grid-connected node according to the node voltage threshold and a preset deviation range.

4. The grid voltage control method for distributed photovoltaics according to claim 1, characterized in that Before the step of, at the grid dispatching layer, according to the current node data and a preset voltage sensitivity matrix, optimizing the reactive power capacity configuration of multiple grid-connected nodes to obtain the photovoltaic capacity of each grid-connected node, it further includes: At the grid dispatching layer, construct a steady-state power flow equation of the power system in polar coordinates according to the node information and line information of the distribution network. Modify and perform matrix transformation on the steady-state power flow equation of the power system to obtain the preset voltage sensitivity matrix. The preset voltage sensitivity matrix is: Among them, Δθ is the phase angle increment of the grid-connected node, ΔU is the voltage increment of the grid-connected node, ΔP is the active power increment of the grid-connected node, ΔQ is the reactive power increment of the grid-connected node, and S1, S2, S3, and S4 are voltage sensitivity coefficients.

5. The grid voltage control method for distributed photovoltaic as claimed in claim 1, wherein, In the grid application layer, according to the photovoltaic capacity and the preset grid state space equation, predicting the power regulation amount of each grid-connected node at a future target time, including: In the grid application layer, according to the photovoltaic capacity, calculating the voltage deviation weight of each grid-connected node; According to the preset grid state space equation, predicting the target node data of multiple grid-connected nodes at the future target time; Using the interior point method, according to the voltage deviation weight, iterating the target node data of multiple grid-connected nodes until the deviation value between the node voltage in the target node data and the preset voltage reference amount reaches the minimum value, and obtaining the power regulation amount of each grid-connected node at the future target time.

6. The grid voltage control method for distributed photovoltaic as claimed in claim 5, characterized in that, The calculating the voltage deviation weight of each grid-connected node according to the photovoltaic capacity includes: Using a preset weight calculation formula, according to the photovoltaic capacity, calculating the voltage deviation weight of each grid-connected node, and the preset weight calculation formula is: ε j represents the voltage deviation weight of the j-th grid-connected node, S PV，j represents the photovoltaic capacity of the j-th grid-connected node, and m represents the total number of grid-connected nodes.

7. The grid voltage control method for distributed photovoltaics according to claim 5, wherein The using the interior point method, according to the voltage deviation weight, iterating the target node data of multiple grid-connected nodes until the deviation value between the node voltage in the target node data and the preset voltage reference amount reaches the minimum value, and obtaining the power regulation amount of each grid-connected node at the future target time includes: Using the interior point method, according to the voltage deviation weight, updating the target node data of the grid-connected node to obtain new target node data; Based on the deviation control function, according to the new target node data, calculating the deviation value between the node voltage in the new target node data and the preset voltage reference value; Taking the active power and reactive power in the new target node data corresponding to the node voltage with the minimum deviation value as the power regulation amount.

8. A grid voltage control device with distributed photovoltaics, characterized in that, Including: An acquisition module, configured to acquire the current node data of multiple grid-connected nodes in the distribution network, where the grid-connected nodes are distributed photovoltaics connected to the distribution network, and the current node data includes node voltage, first active power, and first reactive power; An optimization module, configured to, in the grid dispatching layer, configure and optimize the reactive power capacity of multiple grid-connected nodes according to the current node data and a preset voltage sensitivity matrix, and obtain the photovoltaic capacity of each grid-connected node; where the preset voltage sensitivity matrix is a matrix representing the sensitivity of voltage with respect to active power and reactive power; A prediction module, configured to, in the grid application layer, predict the power regulation amount of each grid-connected node at a future target time according to the photovoltaic capacity and a preset grid state space equation, where the power regulation amount includes second active power and second reactive power; where the preset grid state space equation is a state relationship representing the node voltage and reactive power of multiple grid-connected nodes in the distribution network at a future target time; A sending module, configured to send a voltage control instruction carrying the power regulation amount to a grid-connected inverter, and the grid-connected inverter is configured to execute the voltage control instruction to regulate the grid voltage.

9. A computer device, characterized in that, It includes a processor and a memory, and the memory is used to store a computer program. When the computer program is executed by the processor, it implements the grid voltage control method with distributed photovoltaic as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, It stores a computer program. When the computer program is executed by a processor, it implements the grid voltage control method with distributed photovoltaic as described in any one of claims 1 to 7.

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