A method, device and computer-readable storage medium for controlling power quality of a distribution network

Abstract

The present invention discloses a method, device and computer-readable storage medium for regulating the power quality of a distribution network. The method comprises: determining the installation location of a dynamic voltage restorer and an active power filter by calculating the longitudinal and transverse sensitivities of each node. With the goal of minimizing the investment costs of both, a capacity configuration model is constructed, and corresponding constraints are set. The model is solved under the constraints to obtain a cost-optimal capacity configuration scheme for a dynamic voltage restorer and an active power filter. Based on the site selection and capacity configuration scheme, the dynamic voltage restorer and the active power filter are connected to the distribution network to effectively regulate the power quality of the distribution network. The present invention reduces the number of variables that need to be optimized simultaneously, reduces computational complexity and time consumption, and improves the efficiency and practicality of power quality regulation through equipment site selection and capacity configuration strategies.

Description

Technical Field

[0001] The present invention belongs to the technical field of power quality control in distribution networks, and in particular relates to a method, a device and a computer-readable storage medium for controlling power quality in distribution networks. Background Art

[0002] With the widespread access of nonlinear loads and distributed power sources, distribution networks are facing increasingly severe power quality problems, mainly manifested in voltage surges and dips, current harmonics and other problems.

[0003] To address issues such as voltage sags and current harmonics, current technical strategies rely on intelligent algorithms to synchronize the site selection and capacity configuration of power quality control equipment. Power quality control devices primarily include dynamic voltage restorers, active power filters, and static VAR compensators. However, as the number of access nodes and distribution points in the distribution network increases, the number of variables that require optimization also increases. This significantly increases the computational complexity of intelligent algorithms, making them time-consuming and difficult to solve. These algorithms are therefore unsuitable for distribution networks with complex structures or highly variable operating conditions. Summary of the Invention

[0004] The embodiments of the present invention provide a method, device, and computer-readable storage medium for regulating the power quality of a distribution network, which reduce the number of variables that need to be optimized simultaneously, reduce computational complexity and time consumption, and improve the efficiency and practicality of power quality regulation.

[0005] An embodiment of the present invention provides a method, device, and computer-readable storage medium for controlling power quality in a distribution network, including:

[0006] The sensitivity of a dynamic voltage restorer and an active power filter installed at each node in the distribution network is obtained; wherein the sensitivity includes longitudinal sensitivity and transverse sensitivity.

[0007] The longitudinal sensitivity and transverse sensitivity of the dynamic voltage restorer installed at each node are sorted respectively to obtain a first sorting order and a second sorting order; and the final installation position of the dynamic voltage restorer is determined according to the first sorting order and the second sorting order.

[0008] The longitudinal sensitivity and the transverse sensitivity of each node where the active power filter is installed are sorted respectively to obtain a third sorting order and a fourth sorting order; and the final installation position of the active power filter is determined according to the third sorting order and the fourth sorting order.

[0009] With the goal of minimizing the sum of the investment costs of the dynamic voltage restorer and the active power filter, a capacity configuration model of the dynamic voltage restorer and the active power filter is constructed.

[0010] Constraints for constructing capacity configuration models for dynamic voltage restorers and active power filters.

[0011] Under the constraints of the dynamic voltage restorer and active power filter capacity configuration model, the dynamic voltage restorer and active power filter capacity configuration model is solved to generate the capacity configuration of the dynamic voltage restorer and active power filter when the sum of their investment costs is minimized.

[0012] According to the site selection of the dynamic voltage restorer and the active power filter and the capacity configuration of the dynamic voltage restorer and the active power filter, the dynamic voltage restorer and the active power filter are connected to the distribution network, and then the power quality of the distribution network is regulated.

[0013] Furthermore, the longitudinal sensitivity and transverse sensitivity of the dynamic voltage restorer installed at each node in the distribution network are obtained, including:

[0014] When a dynamic voltage restorer is not installed, the voltage deviation rate of each node in the distribution network is calculated.

[0015] A dynamic voltage restorer with a preset capacity is installed on each node in turn, and the voltage offset rate is calculated respectively to obtain the voltage offset rate of each node in the distribution network after the dynamic voltage restorer is installed.

[0016] The sensitivity coefficient of the dynamic voltage restorer installed at each node is calculated based on the voltage deviation rate before and after the dynamic voltage restorer is installed.

[0017] For each node, the sensitivity coefficient of the node is added to the sensitivity coefficient of the node in a longitudinal relationship with the node to obtain the longitudinal sensitivity of the dynamic voltage restorer installed at the node.

[0018] The sensitivity coefficient of the node is added to the sensitivity coefficients of the nodes that are in a transverse relationship with the node to obtain the transverse sensitivity of the node when the dynamic voltage restorer is installed.

[0019] Furthermore, the longitudinal sensitivity and transverse sensitivity of the active power filter installed at each node in the distribution network are obtained, including:

[0020] When no active power filter is installed, the harmonic voltage distortion rate of each node in the distribution network is calculated.

[0021] An active power filter with a preset capacity is installed on each node in turn, and the harmonic voltage distortion rate is calculated respectively to obtain the harmonic voltage distortion rate of each node in the distribution network after the active power filter is installed.

[0022] The sensitivity coefficient of each node with active power filter installed is calculated based on the harmonic voltage distortion rate before and after the active power filter is installed at each node.

[0023] For each node, the sensitivity coefficient of the node is added to the sensitivity coefficients of the nodes in a longitudinal relationship with the node to obtain the longitudinal sensitivity of the active power filter installed at the node.

[0024] The sensitivity coefficient of the node is added to the sensitivity coefficients of the nodes that are in a transverse relationship with the node to obtain the transverse sensitivity of the active power filter installed at the node.

[0025] Furthermore, the longitudinal sensitivity and the transverse sensitivity of each node for installing the dynamic voltage restorer are sorted respectively to obtain a first sorting order and a second sorting order; and a final installation position of the dynamic voltage restorer is determined according to the first sorting order and the second sorting order, including:

[0026] The longitudinal sensitivity and transverse sensitivity of the dynamic voltage restorer installed on each node are sorted in descending order of sensitivity to obtain a first sorting order and a second sorting order.

[0027] According to the first sorting order, in each vertical structure, the first M nodes are selected as the initial node sequence for installing the dynamic voltage restorer.

[0028] It is determined whether there are adjacent nodes in a vertical relationship with each other in the initial node sequence for installing the dynamic voltage restorer.

[0029] If there are nodes that are vertically adjacent to each other, all the nodes that are vertically adjacent to each other are removed from the initial node sequence where the dynamic voltage restorer is installed, and an updated first node sequence is generated.

[0030] All nodes that are vertically adjacent to each other are put into a first set as a set of candidate nodes for installing a dynamic voltage restorer.

[0031] The nodes in the candidate node set for installing the dynamic voltage restorer are grouped to obtain a plurality of first node groups; wherein the nodes in each first node group are in a vertical relationship with each other and are adjacent.

[0032] According to the second sorting, a node with the largest horizontal sensitivity is selected from each first node group and added to the node sequence after the first update to obtain a second node sequence after the second update.

[0033] According to the second node sequence, a final installation position of the dynamic voltage restorer is determined.

[0034] Furthermore, the longitudinal sensitivity and the transverse sensitivity of each node where the active power filter is installed are sorted respectively to obtain a third sorting order and a fourth sorting order; and the final installation position of the active power filter is determined according to the third sorting order and the fourth sorting order, including:

[0035] The longitudinal sensitivity and transverse sensitivity of the active power filter installed at each node are sorted in descending order of sensitivity to obtain the third sorting order and the fourth sorting order.

[0036] According to the third sorting order, in each longitudinal structure, the first N nodes are selected as the initial node sequence for installing the active power filter.

[0037] It is determined whether there are adjacent nodes in a vertical relationship with each other in the initial node sequence for installing the active power filter.

[0038] If there are nodes that are mutually vertically related and adjacent, all the nodes that are mutually vertically related and adjacent are removed from the initial node sequence where the active power filter is installed, and an updated third node sequence is generated.

[0039] All nodes that are in a vertical relationship and adjacent to each other are put into a second set as a set of candidate nodes for installing the active power filter.

[0040] The nodes in the candidate node set for installing the active power filter are grouped to obtain a plurality of third node groups; wherein the nodes in each third node group are in a vertical relationship with each other and are adjacent;

[0041] According to the fourth sorting, the node with the largest lateral sensitivity is selected from each third node group and added to the node sequence after the first update, so as to obtain the fourth node sequence after the second update.

[0042] According to the fourth node sequence, the final installation position of the active power filter is determined.

[0043] Furthermore, the capacity configuration model includes:

[0044]

[0045]

[0046]

[0047] in, is the objective function; For nodes The installed capacity of dynamic voltage restorer; For nodes Active power filter installation capacity; The number of dynamic voltage restorers installed; The number of active power filters installed; is the cost function; T is the node The cost of installing the active power filter foundation; is the unit capacity cost of the active power filter.

[0048] Furthermore, the constraints include:

[0049] Grid flow security equation constraints, dynamic voltage restorer power quality compensation maximum compensation constraints, active power filter harmonic compensation maximum compensation constraints, node voltage range constraints and node harmonic voltage distortion rate constraints.

[0050] The grid power flow security equation constraint is:

[0051]

[0052] in, Active power injected into the generator; is the injected reactive power; For nodes Active power consumed by the load; is the reactive power consumed; For nodes The voltage amplitude; For nodes The voltage amplitude; For nodes and nodes The admittance between For nodes and nodes The susceptance between For nodes and nodes The phase difference between them.

[0053] The maximum compensation amount constraint of the dynamic voltage restorer power quality compensation is: ;in, For the The maximum capacity of a dynamic voltage restorer.

[0054] The maximum compensation amount constraint of the active power filter harmonic compensation is: ;in, For the Total harmonic compensation capacity of active power filters; For the The reserved capacity factor of the active power filter is used to ensure that the capacity of the active power filter is sufficient to compensate for the disturbance of harmonics; For the Rated capacity of active power filter.

[0055] The node voltage range constraint is: ;in, For nodes voltage; is the lower limit of system voltage; The upper limit of the system voltage.

[0056] The node harmonic voltage distortion rate constraint is: ;in, For nodes The harmonic voltage distortion rate.

[0057] Furthermore, the power quality of the distribution network is regulated, including:

[0058] The reactive power compensation capability of the dynamic voltage restorer and active power filter is utilized to perform reactive power compensation on the voltage of the distribution network.

[0059] Determine whether the active power filter has remaining capacity after reactive power compensation.

[0060] If the active power filter has surplus capacity, the maximum value of the harmonic current that can be compensated is determined based on the surplus capacity, and the harmonics are offset by injecting a current that is equal in magnitude and opposite in direction to the harmonic current.

[0061] Based on the above method embodiments, the present invention provides corresponding device embodiments.

[0062] An embodiment of the present invention provides a device for controlling power quality of a distribution network, comprising: a data acquisition module, a sorting and site selection module, a model construction module, a constraint construction module, a capacity solution module, and a control module.

[0063] The data acquisition module is used to obtain the sensitivity of the dynamic voltage restorer and active power filter installed at each node in the distribution network; wherein the sensitivity includes longitudinal sensitivity and transverse sensitivity.

[0064] The sorting and site selection module is used to sort the longitudinal sensitivity and transverse sensitivity of each node for installing a dynamic voltage restorer, respectively, to obtain a first sorting order and a second sorting order; determine the final installation location of the dynamic voltage restorer based on the first sorting order and the second sorting order; sort the longitudinal sensitivity and transverse sensitivity of each node for installing an active power filter, respectively, to obtain a third sorting order and a fourth sorting order; and determine the final installation location of the active power filter based on the third sorting order and the fourth sorting order.

[0065] The model building module is used to build a capacity configuration model of the dynamic voltage restorer and the active power filter with the goal of minimizing the sum of the investment costs of the dynamic voltage restorer and the active power filter;

[0066] The constraint building module is used to build constraint conditions for the capacity configuration model of the dynamic voltage restorer and the active power filter.

[0067] The capacity solving module is used to solve the capacity configuration model of the dynamic voltage restorer and the active power filter under the constraints of the capacity configuration model of the dynamic voltage restorer and the active power filter, and generate the capacity configuration of the dynamic voltage restorer and the active power filter when the sum of the investment costs of the dynamic voltage restorer and the active power filter is minimized.

[0068] The control module is used to connect the dynamic voltage restorer and the active power filter to the distribution network according to the site selection of the dynamic voltage restorer and the active power filter and the capacity configuration of the dynamic voltage restorer and the active power filter, and then control the power quality of the distribution network.

[0069] Based on the above method embodiment, the present invention provides a corresponding computer-readable storage medium embodiment.

[0070] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for controlling the power quality of a distribution network as described in any one of the above method embodiments can be implemented.

[0071] Compared with the prior art, the present invention has the following beneficial effects:

[0072] The present invention calculates the longitudinal sensitivity and transverse sensitivity of each node, sorts them according to the longitudinal sensitivity and transverse sensitivity, and selects key nodes to determine the installation location of the dynamic voltage restorer and active power filter. A dynamic voltage restorer and active power filter capacity configuration model is constructed with the goal of minimizing the investment cost of the dynamic voltage restorer and active power filter, and corresponding constraints are set. The model is then solved under the constraints to determine the optimal dynamic voltage restorer and active power filter capacity configuration, thereby effectively regulating the distribution network. Compared with the intelligent algorithm used in the prior art, by separately selecting the site and capacity configuration of the dynamic voltage restorer and active power filter, the calculation based on the sensitivity analysis method gives priority to selecting nodes with significant regulation effects for equipment installation, which can reduce the number of variables that need to be optimized simultaneously, reduce the computational complexity and time consumption, and make the optimization process more efficient, thereby effectively regulating the voltage and harmonic problems in the distribution network and improving the overall power quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 It is a flow chart of a method for controlling power quality of a distribution network provided by one embodiment of the present invention.

[0074] Figure 2 The present invention is a schematic structural diagram of a device for controlling the power quality of a distribution network provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0075] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0076] like Figure 1 As shown, an embodiment of the present invention provides a method for controlling the power quality of a distribution network, which includes at least the following steps:

[0077] Step S1: Acquire the sensitivity of a dynamic voltage restorer and an active power filter installed at each node in a distribution network; wherein the sensitivity includes longitudinal sensitivity and transverse sensitivity.

[0078] Specifically, in a preferred embodiment, obtaining the longitudinal sensitivity and transverse sensitivity of a dynamic voltage restorer installed at each node in the distribution network includes:

[0079] When a dynamic voltage restorer is not installed, the voltage deviation rate of each node in the distribution network is calculated.

[0080] A dynamic voltage restorer with a preset capacity is installed on each node in turn, and the voltage offset rate is calculated respectively to obtain the voltage offset rate of each node in the distribution network after the dynamic voltage restorer is installed.

[0081] The sensitivity coefficient of the dynamic voltage restorer installed at each node is calculated based on the voltage deviation rate before and after the dynamic voltage restorer is installed.

[0082] For each node, the sensitivity coefficient of the node is added to the sensitivity coefficient of the node in a longitudinal relationship with the node to obtain the longitudinal sensitivity of the dynamic voltage restorer installed at the node.

[0083] The sensitivity coefficient of the node is added to the sensitivity coefficients of the nodes that are in a transverse relationship with the node to obtain the transverse sensitivity of the node when the dynamic voltage restorer is installed.

[0084] Specifically, in a preferred embodiment, obtaining the longitudinal sensitivity and transverse sensitivity of each node in the distribution network whether an active power filter is installed or not includes:

[0085] When no active power filter is installed, the harmonic voltage distortion rate of each node in the distribution network is calculated.

[0086] An active power filter with a preset capacity is installed on each node in turn, and the harmonic voltage distortion rate is calculated respectively to obtain the harmonic voltage distortion rate of each node in the distribution network after the active power filter is installed.

[0087] The sensitivity coefficient of each node with active power filter installed is calculated based on the harmonic voltage distortion rate before and after the active power filter is installed at each node.

[0088] For each node, the sensitivity coefficient of the node is added to the sensitivity coefficients of the nodes in a longitudinal relationship with the node to obtain the longitudinal sensitivity of the active power filter installed at the node.

[0089] The sensitivity coefficient of the node is added to the sensitivity coefficients of the nodes that are in a transverse relationship with the node to obtain the transverse sensitivity of the active power filter installed at the node.

[0090] Preferably, in the present invention, the calculation formula of the voltage offset rate is as follows:

[0091]

[0092] in, For nodes Voltage deviation rate; For nodes The voltage amplitude; is the voltage amplitude of the first node in the distribution network.

[0093] The calculation formula for the sensitivity coefficient of the dynamic voltage restorer is as follows:

[0094]

[0095] in, For nodes When installing a dynamic voltage restorer and the node The sensitivity coefficient between For nodes After installing a dynamic voltage restorer with a preset capacity, the node The voltage offset rate change value; For nodes The installed capacity of the dynamic voltage restorer.

[0096] Preferably, in the present invention, the calculation formula of harmonic distortion is as follows:

[0097]

[0098] in, For the point Subharmonic voltage effective value; is the fundamental voltage.

[0099] The calculation formula for the active power filter sensitivity coefficient is as follows:

[0100]

[0101] in, For nodes When installing active power filter and node The sensitivity coefficient between For nodes After installing an active power filter with preset capacity, the node The change value of harmonic voltage distortion rate; For nodes Active power filter installation capacity.

[0102] Preferably, the vertical and horizontal relationships between nodes are defined as follows:

[0103] Vertical Relationships: In a radial distribution network, nodes connected to the same feeder are considered to be in a vertical relationship. These nodes are directly connected to the same power transmission path, creating a direct electrical connection between them. If a radial network consists of three feeders, each feeder forms a separate vertical structure, and all nodes on the feeder belong to the same vertical relationship group.

[0104] Horizontal relationships: In a radial distribution network, nodes connected to different feeders are in a horizontal relationship with each other. Although these nodes are not directly connected to the same feeder, they are indirectly connected through other parts of the grid, such as substations or distribution hubs.

[0105] This means that by calculating the voltage excursion rate and harmonic voltage distortion rate at each node before and after the installation of a dynamic voltage restorer and active power filter, it is possible to accurately quantify the specific effect of these devices on improving grid power quality. Based on the sensitivity of each node, the installation location of the dynamic voltage restorer and active power filter can be more rationally planned, achieving optimal resource allocation and maximizing the overall power quality improvement of the grid.

[0106] Step S2: sort the longitudinal sensitivity and transverse sensitivity of each node to obtain a first sorting order and a second sorting order; determine the final installation position of the dynamic voltage restorer according to the first sorting order and the second sorting order.

[0107] Specifically, in a preferred embodiment, the longitudinal sensitivity and the transverse sensitivity of each node for installing a dynamic voltage restorer are sorted respectively to obtain a first sorting order and a second sorting order; and the final installation position of the dynamic voltage restorer is determined according to the first sorting order and the second sorting order, including:

[0108] The longitudinal sensitivity and transverse sensitivity of the dynamic voltage restorer installed on each node are sorted in descending order of sensitivity to obtain a first sorting order and a second sorting order.

[0109] According to the first sorting order, in each vertical structure, the first M nodes are selected as the initial node sequence for installing the dynamic voltage restorer.

[0110] It is determined whether there are adjacent nodes in a vertical relationship with each other in the initial node sequence for installing the dynamic voltage restorer.

[0111] If there are nodes that are vertically adjacent to each other, then all the nodes that are vertically adjacent to each other are removed from the initial node sequence where the dynamic voltage restorer is installed, to generate an updated first node sequence;

[0112] All nodes that are vertically adjacent to each other are put into a first set as a set of candidate nodes for installing a dynamic voltage restorer.

[0113] The nodes in the candidate node set for installing the dynamic voltage restorer are grouped to obtain a plurality of first node groups; wherein the nodes in each first node group are in a vertical relationship with each other and are adjacent.

[0114] According to the second sorting, a node with the largest horizontal sensitivity is selected from each first node group and added to the node sequence after the first update to obtain a second node sequence after the second update.

[0115] According to the second node sequence, a final installation position of the dynamic voltage restorer is determined.

[0116] Preferably, in the present invention, M in the first M nodes is a positive integer, such as 3, 4, 5, etc.

[0117] For example, if, according to a first sorting order, the first 12 nodes are selected as the initial node sequence for installing a dynamic voltage restorer, and five of these nodes are vertically adjacent, then these five nodes are removed from the initial node sequence for installing the dynamic voltage restorer, generating a first node sequence after a single update, which contains seven nodes. The five removed nodes are then placed into a first set, which serves as the candidate node set for installing the dynamic voltage restorer. The five nodes in the candidate node set for installing the dynamic voltage restorer are grouped based on whether they are vertically adjacent, resulting in two groups: one containing three nodes and the other containing two nodes, with the nodes being vertically adjacent. According to a second sorting order, the node with the highest transverse sensitivity in each group is selected, resulting in two nodes for each group. These two nodes are then added to the seven nodes in the first node sequence after a single update, generating a second node sequence after a second update, which contains nine nodes. These nine nodes are used as the final installation locations for the dynamic voltage restorer.

[0118] This means that removing adjacent nodes that are in a vertical relationship from the initial sequence of nodes for installing dynamic voltage restorers can effectively avoid redundant installation of dynamic voltage restorers at these locations. Since these nodes are electrically closely connected, the voltage fluctuations between them usually have similar characteristics. Therefore, installing a dynamic voltage restorer on one of the nodes can often indirectly improve the voltage quality of the adjacent nodes. In addition, grouping adjacent nodes that are in a vertical relationship and selecting the node with the greatest lateral sensitivity from each group for installation can ensure that the lateral improvement effect is maximized while maintaining the longitudinal improvement effect. This helps to improve the resource utilization efficiency of the dynamic voltage restorer and avoid unnecessary waste.

[0119] Step S3: sorting the longitudinal sensitivity and transverse sensitivity of each node for installing the active power filter to obtain a third sorting order and a fourth sorting order; and determining the final installation position of the active power filter according to the third sorting order and the fourth sorting order.

[0120] Specifically, in a preferred embodiment, the longitudinal sensitivity and the transverse sensitivity of each node when the active power filter is installed are sorted respectively to obtain a third sorting order and a fourth sorting order; and the final installation position of the active power filter is determined according to the third sorting order and the fourth sorting order, including:

[0121] The longitudinal sensitivity and transverse sensitivity of the active power filter installed at each node are sorted in descending order of sensitivity to obtain the third sorting order and the fourth sorting order.

[0122] According to the third sorting order, in each longitudinal structure, the first N nodes are selected as the initial node sequence for installing the active power filter.

[0123] It is determined whether there are adjacent nodes in a vertical relationship with each other in the initial node sequence for installing the active power filter.

[0124] If there are nodes that are mutually vertically related and adjacent, all the nodes that are mutually vertically related and adjacent are removed from the initial node sequence where the active power filter is installed, and an updated third node sequence is generated.

[0125] All nodes that are in a vertical relationship and adjacent to each other are put into a second set as a set of candidate nodes for installing the active power filter.

[0126] The nodes in the candidate node set for installing the active power filter are grouped to obtain a plurality of third node groups; wherein the nodes in each third node group are in a vertical relationship with each other and are adjacent.

[0127] According to the fourth sorting, the node with the largest lateral sensitivity is selected from each third node group and added to the node sequence after the first update, so as to obtain the fourth node sequence after the second update.

[0128] According to the fourth node sequence, the final installation position of the active power filter is determined.

[0129] Preferably, in the present invention, N in the first N nodes is a positive integer, such as 3, 4, 5, etc.

[0130] For example, if, according to the third sorting order, the first 15 nodes are selected as the initial node sequence for installing the active power filter, and five of these nodes are vertically adjacent to each other, then these five nodes are removed from the initial node sequence for installing the active power filter to generate a single-updated third node sequence containing 10 nodes. The removed five nodes are then placed into a second set, which serves as the candidate node set for installing the active power filter. The five nodes in the candidate node set for installing the active power filter are grouped based on whether they are vertically adjacent to each other, resulting in two groups: one containing three nodes and the other containing two nodes, with the nodes being vertically adjacent to each other. According to the fourth sorting order, the nodes with the highest transverse sensitivity in each group are selected, resulting in two nodes for each group. These two nodes are then added to the 10 nodes in the single-updated third node sequence to generate a second-updated fourth node sequence containing 12 nodes. These 12 nodes are used as the final installation locations for the active power filter.

[0131] This means that by removing adjacent nodes that are vertically related to each other from the initial node sequence for installing active power filters, redundant active power filters can be avoided at these locations, optimizing resource allocation and ensuring more reasonable installation locations for active power filters, thereby achieving maximum harmonic suppression effects within limited resources. This helps to more effectively control harmonic propagation in the power grid and improve the stability of the entire grid.

[0132] Step S4: constructing a capacity configuration model of the dynamic voltage restorer and the active power filter with the goal of minimizing the sum of the investment costs of the dynamic voltage restorer and the active power filter.

[0133] Specifically, in a preferred embodiment, the capacity configuration model includes:

[0134]

[0135]

[0136]

[0137] in, is the objective function; For nodes The installed capacity of dynamic voltage restorer; For nodes Active power filter installation capacity; The number of dynamic voltage restorers installed; The number of active power filters installed; is the cost function; T is the node The cost of installing the active power filter foundation; is the unit capacity cost of the active power filter.

[0138] Preferably, is the cost function; For nodes Cost function of the dynamic voltage restorer installation capacity; For nodes Cost function of active power filter installation capacity.

[0139] This means that by building a capacity configuration model, resources can be rationally allocated to ensure that the capacity configuration of the dynamic voltage restorer and active power filter meets system requirements without wasting resources. This can reduce unnecessary investment and maximize cost-effectiveness.

[0140] Step S5: Constructing constraint conditions for the capacity configuration model of the dynamic voltage restorer and active power filter.

[0141] Specifically, in a preferred embodiment, the constraints include:

[0142] Grid power flow security equation constraints, dynamic voltage restorer power quality compensation maximum compensation constraints, active power filter harmonic compensation maximum compensation constraints, node voltage range constraints, and node harmonic voltage distortion rate constraints;

[0143] The grid power flow security equation constraint is:

[0144]

[0145] in, Active power injected into the generator; is the injected reactive power; For nodes Active power consumed by the load; is the reactive power consumed; For nodes The voltage amplitude; For nodes The voltage amplitude; For nodes and nodes The admittance between For nodes and nodes The susceptance between For nodes and nodes The phase difference between them.

[0146] The maximum compensation amount constraint of the dynamic voltage restorer power quality compensation is: ;in, For the The maximum capacity of a dynamic voltage restorer.

[0147] The maximum compensation amount constraint of the active power filter harmonic compensation is: ;in, For the Total harmonic compensation capacity of active power filters; For the The reserved capacity factor of the active power filter is used to ensure that the capacity of the active power filter is sufficient to compensate for the disturbance of harmonics; For the Rated capacity of active power filter.

[0148] The node voltage range constraint is: ;in, For nodes voltage; is the lower limit of system voltage; The upper limit of the system voltage.

[0149] The node harmonic voltage distortion rate constraint is: ;in, For nodes The harmonic voltage distortion rate.

[0150] This means that by building constraints, the distribution network can ensure that it can meet power balance at all times, comply with power policies and power quality standards, and ensure that the compensation operations of dynamic voltage restorers and active power filters do not exceed the capabilities of the equipment.

[0151] Step S6: Under the constraints of the dynamic voltage restorer and active power filter capacity configuration model, the dynamic voltage restorer and active power filter capacity configuration model is solved to generate the capacity configuration of the dynamic voltage restorer and active power filter when the sum of the investment costs of the dynamic voltage restorer and active power filter is minimized.

[0152] Specifically, in a preferred embodiment, an improved particle swarm algorithm is used to solve the capacity configuration model, and the particle swarm size, number of iterations, spatial dimension, inertia weight, and learning factor are set according to the capacity configuration model.

[0153] Calculate the fitness of each particle; the fitness value represents the sum of the investment costs of the dynamic voltage restorer and the active power filter.

[0154] Update the individual and global optimal values. The individual optimal value is the best position found by each particle during the search and its corresponding fitness. The global optimal value is the best position found by all particles and their corresponding fitness. The position of each particle represents the output capacity of the dynamic voltage restorer or active power filter.

[0155] Update the particle velocity, position, and inertia weight until the particle fitness meets the constraints of the capacity configuration model and the fitness satisfies the minimum investment cost or the number of iterations reaches the maximum number of iterations, and output the capacity configuration of the dynamic voltage restorer or active power filter.

[0156] The formula for particles to update their own speed, position and inertia weight is as follows:

[0157]

[0158]

[0159]

[0160] in, is the current iteration number; and For particles No. Dimensional speed and position; and is the learning factor, and is a random number between [0,1]; and Represent the maximum and minimum values ​​of the weight respectively; is the current iteration number; Indicates the maximum number of iterations.

[0161] Optionally, the present invention can set the maximum number of iterations of the particle swarm to 800, the spatial dimension to 6, the number of particles to 100, the maximum and minimum values ​​of the inertia weight to 0.9 and 0.4 respectively, and the learning factor to and is 2. The maximum number of iterations is set to 300.

[0162] This means that the improved particle swarm algorithm, with its rapid convergence speed, can find a near-optimal solution in a relatively short time, helping to determine the optimal capacity configuration for dynamic voltage restorers and active power filters, effectively reducing investment costs while meeting the operational requirements of the power system, reducing voltage fluctuations and harmonic distortion, and ensuring power system stability and voltage quality. Furthermore, the improved particle swarm algorithm's automated nature reduces manual intervention and improves the efficiency and accuracy of the distribution network control process.

[0163] Step S7: Connect the dynamic voltage restorer and the active power filter to the distribution network according to the site selection and capacity configuration of the dynamic voltage restorer and the active power filter, and then regulate the power quality of the distribution network.

[0164] Specifically, in a preferred embodiment, regulating the power quality of the distribution network includes: utilizing the reactive power compensation capabilities of a dynamic voltage restorer and an active power filter to perform reactive power compensation on the voltage of the distribution network;

[0165] Determine whether the active power filter has remaining capacity after reactive power compensation;

[0166] If the active power filter has surplus capacity, the maximum value of the harmonic current that can be compensated is determined based on the surplus capacity, and the harmonics are offset by injecting a current that is equal in magnitude and opposite in direction to the harmonic current.

[0167] Preferably, the compensation values ​​of the dynamic voltage restorer and the active power filter in the distribution network are initialized.

[0168] Calculate the voltage deviation rate of all nodes in the distribution network and determine whether the voltage deviation rate of all nodes meets the voltage deviation rate requirement of the distribution network.

[0169] If the voltage deviation rate requirement of the distribution network is not met, the remaining capacity of the dynamic voltage restorer and active power filter will be called for reactive power compensation in the order of priority until the voltage deviation rate of all nodes meets the voltage deviation rate requirement of the distribution network or the capacity of the dynamic voltage restorer and active power filter is exhausted.

[0170] If the requirements of the distribution network voltage deviation rate are met, it means that the voltage problem has been solved at this time, and there is no need to use the reactive compensation capabilities of the dynamic voltage restorer and active power filter to perform reactive compensation on the voltage of the distribution network.

[0171] On the basis of solving the voltage problem, the voltage harmonic distortion rate of all nodes in the distribution network is determined and calculated, and it is determined whether the voltage harmonic distortion rate of all nodes meets the requirements of the distribution network voltage harmonic distortion rate.

[0172] If the requirements of the voltage harmonic distortion rate of the distribution network are not met, it is determined whether the active power filter has residual capacity. If the active power filter has residual capacity, the maximum value of the harmonic current that can be compensated is determined based on the residual capacity, and the harmonics are offset by injecting a current equal to the harmonic current in magnitude and opposite in direction until the voltage harmonic distortion rate meets the requirements of the voltage harmonic distortion rate of the distribution network.

[0173] If the requirements for the harmonic distortion rate of the distribution network voltage are met, it means that the harmonic problem has been solved and there is no need to inject a current equal to the harmonic current and opposite in direction to offset the harmonics.

[0174] This means that by optimizing the compensation values ​​of the dynamic voltage restorer and active power filter, voltage offsets and voltage fluctuations can be reduced, thereby improving the voltage quality of the entire distribution network. Furthermore, the voltage harmonic distortion rate can be reduced, minimizing the impact on power equipment and consumers, and improving the stability of the distribution network.

[0175] Based on the above method embodiments, the present invention provides corresponding device embodiments.

[0176] like Figure 2 As shown, an embodiment of the present invention provides a device for controlling the power quality of a distribution network, including: a data acquisition module 101, a sorting and site selection module 102, a model construction module 103, a constraint construction module 104, a capacity solution module 105 and a control module 106.

[0177] The data acquisition module 101 is used to acquire the sensitivity of the dynamic voltage restorer and active power filter installed at each node in the distribution network, wherein the sensitivity includes longitudinal sensitivity and transverse sensitivity.

[0178] The sorting and site selection module 102 is used to sort the longitudinal sensitivity and transverse sensitivity of each node for installing a dynamic voltage restorer, respectively, to obtain a first sorting order and a second sorting order; determine the final installation location of the dynamic voltage restorer based on the first sorting order and the second sorting order; sort the longitudinal sensitivity and transverse sensitivity of each node for installing an active power filter, respectively, to obtain a third sorting order and a fourth sorting order; and determine the final installation location of the active power filter based on the third sorting order and the fourth sorting order.

[0179] The model building module 103 is used to build a capacity configuration model of the dynamic voltage restorer and the active power filter with the goal of minimizing the sum of the investment costs of the dynamic voltage restorer and the active power filter.

[0180] The constraint building module 104 is used to build constraint conditions for the capacity configuration model of the dynamic voltage restorer and the active power filter.

[0181] The capacity solving module 105 is used to solve the capacity configuration model of the dynamic voltage restorer and the active power filter under the constraints of the capacity configuration model of the dynamic voltage restorer and the active power filter, and generate the capacity configuration of the dynamic voltage restorer and the active power filter when the sum of the investment costs of the dynamic voltage restorer and the active power filter is minimized.

[0182] The control module 106 is used to connect the dynamic voltage restorer and the active power filter to the distribution network according to the site selection of the dynamic voltage restorer and the active power filter and the capacity configuration of the dynamic voltage restorer and the active power filter, and then control the power quality of the distribution network.

[0183] Another embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for controlling the power quality of a distribution network according to the present invention is implemented.

[0184] It should be noted that the device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed across multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment. In addition, in the drawings of the device embodiments provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, which may be specifically implemented as one or more communication buses or signal lines. A person of ordinary skill in the art can understand and implement the present invention without inventive effort.

[0185] The computer program includes computer program code, which may be in source code form, object code form, executable file or some intermediate form. The computer-readable storage medium may include: any entity or device, medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory, random access memory, electric carrier signal, telecommunication signal and software distribution medium that can carry the computer program code. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals. For ease of explanation, the above content only shows the part related to the embodiment of the present invention. For specific technical details not disclosed, please refer to the method part of the embodiment of the present invention. The computer-readable storage medium is non-transitory and can be stored in a storage device formed by various electronic devices, and can implement the execution process recorded in the method of the embodiment of the present invention.

[0186] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROMs, optical storage, etc.) containing computer-usable program code.

[0187] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts 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, 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 processes in the flowcharts and / or block diagrams. 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.

[0188] 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 comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0189] 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 1 A step that specifies a function in one or more boxes.

[0190] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for controlling the power quality of a distribution network, characterized in that: include: Obtaining the sensitivity of a dynamic voltage restorer and an active power filter installed at each node in the distribution network; wherein the sensitivity includes longitudinal sensitivity and transverse sensitivity; sorting the longitudinal sensitivity and the transverse sensitivity of the dynamic voltage restorer installed at each node to obtain a first sorting order and a second sorting order; and determining a final installation position of the dynamic voltage restorer according to the first sorting order and the second sorting order; sorting the longitudinal sensitivity and the transverse sensitivity of each node where the active power filter is installed to obtain a third sorting order and a fourth sorting order; and determining a final installation position of the active power filter according to the third sorting order and the fourth sorting order; With the goal of minimizing the sum of the investment costs of the dynamic voltage restorer and active power filter, a capacity configuration model for the dynamic voltage restorer and active power filter is constructed. Construct constraints for dynamic voltage restorer and active power filter capacity configuration models; Under the constraints of the capacity configuration model of the dynamic voltage restorer and the active power filter, the capacity configuration model of the dynamic voltage restorer and the active power filter is solved to generate the capacity configuration of the dynamic voltage restorer and the active power filter when the sum of the investment costs of the dynamic voltage restorer and the active power filter is minimized; According to the site selection of the dynamic voltage restorer and the active power filter and the capacity configuration of the dynamic voltage restorer and the active power filter, the dynamic voltage restorer and the active power filter are connected to the distribution network, and the power quality of the distribution network is then regulated; The capacity configuration model includes: in, is the objective function; For nodes The installed capacity of dynamic voltage restorer; For nodes Active power filter installation capacity; The number of dynamic voltage restorers installed; The number of active power filters installed; is the cost function; T is the node The cost of installing the active power filter foundation; is the unit capacity cost of the active power filter.

2. The method for controlling the power quality of a distribution network according to claim 1, wherein: Obtain the longitudinal sensitivity and transverse sensitivity of the dynamic voltage restorer installed at each node in the distribution network, including: When no dynamic voltage restorer is installed, the voltage deviation rate of each node in the distribution network is calculated; A dynamic voltage restorer with a preset capacity is installed on each node in turn, and the voltage offset rate is calculated respectively to obtain the voltage offset rate of each node in the distribution network after the dynamic voltage restorer is installed; Calculate the sensitivity coefficient of each node for installing a dynamic voltage restorer based on the voltage deviation rate before and after the dynamic voltage restorer is installed. For each node, the sensitivity coefficient of the node is added to the sensitivity coefficient of the node in a longitudinal relationship with the node to obtain the longitudinal sensitivity of the dynamic voltage restorer installed at the node; The sensitivity coefficient of the node is added to the sensitivity coefficients of the nodes that are in a transverse relationship with the node to obtain the transverse sensitivity of the node when the dynamic voltage restorer is installed.

3. The method for controlling the power quality of a distribution network according to claim 1, wherein: Obtain the longitudinal sensitivity and transverse sensitivity of the active power filter installed at each node in the distribution network, including: Calculate the harmonic voltage distortion rate at each node of the distribution network when no active power filter is installed; An active power filter of preset capacity is installed at each node in turn, and the harmonic voltage distortion rate is calculated respectively to obtain the harmonic voltage distortion rate of each node in the distribution network after the active power filter is installed; Calculate the sensitivity coefficient of each node after installing the active power filter based on the harmonic voltage distortion rate before and after installing the active power filter. For each node, the sensitivity coefficient of the node is added to the sensitivity coefficient of the node in a longitudinal relationship with the node to obtain the longitudinal sensitivity of the active power filter installed at the node; The sensitivity coefficient of the node is added to the sensitivity coefficients of the nodes that are in a transverse relationship with the node to obtain the transverse sensitivity of the active power filter installed at the node.

4. The method for controlling the power quality of a distribution network according to claim 1, wherein: Sorting the longitudinal sensitivity and the transverse sensitivity of each node for installing a dynamic voltage restorer respectively to obtain a first sorting order and a second sorting order; and determining a final installation position of the dynamic voltage restorer according to the first sorting order and the second sorting order, including: The longitudinal sensitivity and transverse sensitivity of the dynamic voltage restorer installed on each node are sorted in descending order of sensitivity to obtain a first sorting order and a second sorting order; According to the first sorting order, in each vertical structure, the first M nodes are selected as the initial node sequence for installing the dynamic voltage restorer; Determine whether there are any nodes in the initial node sequence where the dynamic voltage restorer is installed that are vertically related and adjacent to each other; If there are nodes that are vertically adjacent to each other, then all the nodes that are vertically adjacent to each other are removed from the initial node sequence where the dynamic voltage restorer is installed, to generate an updated first node sequence; All nodes that are vertically adjacent to each other are put into a first set as a set of candidate nodes for installing a dynamic voltage restorer; Grouping the nodes in the candidate node set for installing the dynamic voltage restorer to obtain a plurality of first node groups; wherein the nodes in each first node group are in a vertical relationship and adjacent to each other; According to the second sorting, a node with the largest horizontal sensitivity is selected from each first node group, and added to the node sequence after the first update, to obtain a second node sequence after the second update; According to the second node sequence, a final installation position of the dynamic voltage restorer is determined.

5. The method for controlling the power quality of a distribution network according to claim 1, wherein: The longitudinal sensitivity and the transverse sensitivity of each node where the active power filter is installed are sorted respectively to obtain a third sorting order and a fourth sorting order; and a final installation position of the active power filter is determined according to the third sorting order and the fourth sorting order, including: The longitudinal sensitivity and transverse sensitivity of the active power filter installed at each node are sorted in descending order of sensitivity to obtain the third sorting order and the fourth sorting order; According to the third sorting order, in each longitudinal structure, the first N nodes are selected as the initial node sequence for installing the active power filter; Determine whether there are any nodes in a vertical relationship and adjacent to each other in the initial node sequence for installing the active power filter; If there are nodes that are mutually vertically related and adjacent, then all the nodes that are mutually vertically related and adjacent are removed from the initial node sequence where the active power filter is installed, and an updated third node sequence is generated; All nodes that are in a vertical relationship and adjacent to each other are put into a second set as a set of candidate nodes for installing active power filters; The nodes in the candidate node set for installing the active power filter are grouped to obtain a plurality of third node groups; wherein the nodes in each third node group are in a vertical relationship with each other and are adjacent; According to the fourth sorting, a node with the largest horizontal sensitivity is selected from each third node group, and added to the node sequence after the first update, to obtain a fourth node sequence after the second update; According to the fourth node sequence, the final installation position of the active power filter is determined.

6. The method for controlling the power quality of a distribution network according to claim 1, wherein: The constraints include: Grid power flow security equation constraints, dynamic voltage restorer power quality compensation maximum compensation constraints, active power filter harmonic compensation maximum compensation constraints, node voltage range constraints, and node harmonic voltage distortion rate constraints; The grid power flow security equation constraint is: in, Active power injected into the generator; is the injected reactive power; For nodes Active power consumed by the load; is the reactive power consumed; For nodes The voltage amplitude; For nodes The voltage amplitude; For nodes and nodes The admittance between For nodes and nodes The susceptance between For nodes and nodes The phase difference between The maximum compensation amount constraint of the dynamic voltage restorer power quality compensation is: ;in, For the Maximum capacity of a dynamic voltage restorer; The maximum compensation amount constraint of the active power filter harmonic compensation is: ;in, For the Total harmonic compensation capacity of active power filters; For the The reserved capacity factor of the active power filter is used to ensure that the capacity of the active power filter is sufficient to compensate for the disturbance of harmonics; For the Rated capacity of active power filter; The node voltage range constraint is: ;in, For nodes voltage; is the lower limit of system voltage; is the upper limit of system voltage; The node harmonic voltage distortion rate constraint is: ;in, For nodes The harmonic voltage distortion rate.

7. The method for controlling the power quality of a distribution network according to claim 1, wherein: Control the power quality of the distribution network, including: Utilize the reactive power compensation capability of dynamic voltage restorer and active power filter to compensate the voltage of distribution network for reactive power; Determine whether the active power filter has remaining capacity after reactive power compensation; If the active power filter has surplus capacity, the maximum value of the harmonic current that can be compensated is determined based on the surplus capacity, and the harmonics are offset by injecting a current that is equal in magnitude and opposite in direction to the harmonic current.

8. A device for controlling the power quality of a distribution network, characterized in that: include: Data acquisition module, sorting and site selection module, model building module, constraint building module, capacity solving module and control module; The data acquisition module is used to obtain the sensitivity of the dynamic voltage restorer and active power filter installed at each node in the distribution network; wherein the sensitivity includes longitudinal sensitivity and transverse sensitivity; The sorting and site selection module is used to sort the longitudinal sensitivity and transverse sensitivity of each node for installing a dynamic voltage restorer to obtain a first sorting order and a second sorting order; determine the final installation location of the dynamic voltage restorer based on the first sorting order and the second sorting order; sort the longitudinal sensitivity and transverse sensitivity of each node for installing an active power filter to obtain a third sorting order and a fourth sorting order; determine the final installation location of the active power filter based on the third sorting order and the fourth sorting order; The model building module is used to build a capacity configuration model of the dynamic voltage restorer and the active power filter with the goal of minimizing the sum of the investment costs of the dynamic voltage restorer and the active power filter; The constraint building module is used to build the constraint conditions of the dynamic voltage restorer and active power filter capacity configuration model; The capacity solving module is used to solve the capacity configuration model of the dynamic voltage restorer and the active power filter under the constraints of the capacity configuration model of the dynamic voltage restorer and the active power filter, and generate the capacity configuration of the dynamic voltage restorer and the active power filter when the sum of the investment costs of the dynamic voltage restorer and the active power filter is minimized; The control module is used to connect the dynamic voltage restorer and the active power filter to the distribution network according to the site selection of the dynamic voltage restorer and the active power filter and the capacity configuration of the dynamic voltage restorer and the active power filter, and then control the power quality of the distribution network; The capacity configuration model includes: in, is the objective function; For nodes The installed capacity of dynamic voltage restorer; For nodes Active power filter installation capacity; The number of dynamic voltage restorers installed; The number of active power filters installed; is the cost function; T is the node The cost of installing the active power filter foundation; is the unit capacity cost of the active power filter.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, it can implement the method for controlling the power quality of a distribution network as described in any one of claims 1 to 7.

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