Automatic power control method and device for elastic power distribution network

Abstract

The invention discloses an automatic power control method for an elastic power distribution network, and the method is suitable for the elastic power distribution network which comprises a plurality of endpoints. The method comprises the following steps: acquiring topological information of a communication network of a current elastic power distribution network, and generating a communication link matrix corresponding to the current elastic power distribution network according to the topological information; according to the communication link matrix and the output power output by the converter port of each new energy DG, obtaining the reference power automatically controlled by the elastic power distribution network; calculating a power instruction value of droop control of each new energy DG according to the reference power; and performing droop control on each DG in the elastic power distribution network according to the power instruction value during droop control. According to the invention, when the network fails and the network topology is changed, the output power of the power distribution network can reach the preset power in a self-adaptive manner through droop power control, so that the power lost by the failed line is made up.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent power distribution, and particularly relates to a method and device for automatic power control of an elastic distribution network. Background Art

[0002] During normal operation, the distribution network system in a small area is connected to the main grid for operation. In the event of interference, it disconnects from the main grid and enters the island operation mode. Once the distribution network system becomes independent from the main grid, primary control is used to maintain the stability of voltage and frequency. However, primary control will cause voltage and frequency deviations. In order to restore the voltage and frequency of distributed generation to their nominal values, secondary control is required. However, traditional secondary control often adopts a centralized control structure, which requires a high communication cost. Distributed secondary control reduces the communication cost of the distribution network system. However, its design often assumes that the communication topology of the distribution network system does not fail. However, with the increasing complexity of the distribution network system, the probability of failure of its communication structure also increases. The circuit failure of the local communication structure will affect the overall performance of the distribution network system. Summary of the Invention

[0003] In view of the above problems, the present invention is proposed to provide a method and device for automatic power control of an elastic distribution network that overcomes or at least partially solves the above problems.

[0004] In a first aspect, an embodiment of the present invention provides a method for automatic power control of an elastic distribution network, which is applicable to the elastic distribution network. The elastic distribution network includes multiple endpoints; multiple new energy distributed generation devices DG are respectively connected to the multiple endpoints. The method includes:

[0005] Obtain the topology information of the communication network of the current elastic distribution network, and generate a communication link matrix corresponding to the current elastic distribution network according to the topology information;

[0006] Obtain the reference power for automatic control of the elastic distribution network according to the communication link matrix and the output power output from the converter ports of each new energy DG;

[0007] Calculate the power command value for droop control of each new energy DG according to the reference power;

[0008] Perform droop control on each DG in the elastic distribution network according to the power command value during droop control.

[0009] In one embodiment, detecting the topology information of the communication network of the current elastic distribution network, and generating a communication link matrix corresponding to the current elastic distribution network according to the topology information includes:

[0010] Determine the adjacency matrix and the in-degree matrix according to the topological state of the communication network of the distribution network;

[0011] Obtain the communication link matrix according to the adjacency matrix and the in-degree matrix.

[0012] In one embodiment, determining the adjacency matrix and the in-degree matrix according to the topological state of the communication network of the distribution network includes:

[0013] Model the topological state of the communication network of the distribution network system in the form of a graph to obtain a communication graph G=(V, E, A), where the distributed new energy DG is the node of the communication graph; the edges of the communication graph represent communication links;

[0014] In the above formula, V represents the set of vertices, E represents the set of arcs, A represents the adjacency matrix. For a non-empty finite set V={v1, v2,..., v N}, the set of arcs is defined as Adjacency matrix Define the in-degree matrix as where

[0015] In one embodiment, obtaining the communication link matrix according to the adjacency matrix and the in-degree matrix includes:

[0016] Define the communication link matrix L = D - A, and the sum of all rows of L is equal to zero.

[0017] In one embodiment, the reference power is the active reference power; obtaining the reference power for the automatic control of the flexible distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG includes:

[0018] According to the adjacency matrix, the active power droop coefficient when performing droop control on each new energy DG, the sampled value of the active power output by the converter port of each new energy DG, and the sampled value of the active power output by the new energy DG adjacent to each new energy DG in the communication graph, calculate the first local area tracking error of each new energy DG;

[0019] According to the first local area tracking error, obtain the reciprocal of the active power secondary control response time, and integrate the reciprocal of the active power secondary response time to obtain the active reference power of each new energy DG used for droop control.

[0020] In one embodiment, the reference power is the reactive reference power; obtaining the reference power for the automatic control of the flexible distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG includes:

[0021] According to the adjacency matrix, the target weight value of the reference power of the new energy DG, the sampled value of the reactive power output by the converter port of each new energy DG, and the sampled value of the reactive power output by the adjacent new energy DGs of each new energy DG in the communication graph, calculate the second local area tracking error of each new energy DG;

[0022] According to the second local area tracking error, obtain the reciprocal of the secondary control response time of the reactive power, and integrate the reciprocal of the secondary response time of the reactive power to obtain the active reference power of each new energy DG used for droop control.

[0023] In one embodiment, according to the power command value during the droop control, perform droop control on each new energy DG in the elastic distribution network, including:

[0024] According to the active power command values of each new energy DG carried in the issued active power command, perform primary control on each new energy DG. The primary control uses droop control to control the output frequency and output voltage of each new energy DG;

[0025] And according to the reactive power command values of each energy DG carried in the issued reactive power command, perform primary control on the new energy DG. The primary control uses droop control to control the output frequency and output voltage of each new energy DG.

[0026] In a second aspect, an embodiment of the present invention provides a power automatic control device for an elastic distribution network. The device is applicable to the elastic distribution network, and the elastic distribution network includes multiple endpoints; multiple new energy distributed generation devices DG, which are respectively connected to the multiple endpoints, including:

[0027] An acquisition module, configured to acquire the topological information of the communication network of the current elastic distribution network, and generate a communication link matrix corresponding to the current elastic distribution network according to the topological information;

[0028] A calculation module, configured to obtain the reference power for the automatic control of the elastic distribution network according to the communication link matrix and the output power output by the converter port of each new energy DG; calculate the power for each new energy DG to perform droop control according to the reference power;

[0029] A control module, configured to perform droop control on each DG in the elastic distribution network according to the power during the droop control, so that each DG reaches the corresponding reference power.

[0030] In a third aspect, an embodiment of the present invention provides a control device for an elastic distribution network, including: a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the automatic power control method for the elastic distribution network is implemented.

[0031] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the automatic power control method for the elastic distribution network is implemented.

[0032] The beneficial effects of the above technical solutions provided by the embodiments of the present invention at least include:

[0033] The present invention discloses an automatic power control method for an elastic distribution network. The method is applicable to an elastic distribution network, which includes multiple endpoints; multiple new energy distributed generation devices DG, respectively connected to the multiple endpoints. The method includes: obtaining the topology information of the communication network of the current elastic distribution network, and generating a communication link matrix corresponding to the current elastic distribution network according to the topology information; obtaining the reference power for the automatic control of the elastic distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG; calculating the power for each new energy DG to perform droop control according to the reference power; and performing droop control on each DG in the elastic distribution network according to the power during the droop control. Embodiments of the present invention can achieve full intercommunication of the communication topologies between new energy DGs without faults. When a single-point fault occurs between any two new energy DGs, the entire power distribution system can still maintain global connectivity. Moreover, when a network fault occurs and the network topology changes, the output power of the distribution network can still be adaptively adjusted to reach the preset power through droop power control, compensating for the power lost by the faulty line.

[0034] Other features and advantages of the present invention will be described in the following specification, and will be partially apparent from the specification, or understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the written specification, claims, and drawings.

[0035] The technical solutions of the present invention will be further described in detail below with reference to the drawings and embodiments. Description of the Drawings

[0036] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation to the present invention. In the drawings:

[0037] Figure 1 It is a flowchart of the automatic power control method for the elastic distribution network in an embodiment of the present invention;

[0038] Figure 2 This is the topological structure diagram of the flexible distribution network in the embodiment of the present invention;

[0039] Figure 3 This is the structural block diagram of the power control device in the embodiment of the present invention;

[0040] Figure 4 This is the structural block diagram of the automatic power control device of the flexible distribution network in the embodiment of the present invention

[0041] Figure 5 This is the flow chart of droop control by the reactive power command and the active power command in the embodiment of the present invention. Detailed implementation manners

[0042] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0043] To solve the problem that the overall performance of the existing distribution system is affected after a local failure occurs in the distribution system, an embodiment of the present invention provides an automatic power control method for a flexible distribution network. This method is applicable to a flexible distribution network, and the flexible distribution network includes multiple endpoints; multiple new energy distributed generation devices DG, which are respectively connected to the multiple endpoints. The flow chart of this method is as Figure 1 shown and includes:

[0044] S11. Obtain the topological information of the communication network of the current flexible distribution network, and generate a communication link matrix corresponding to the current flexible distribution network according to the topological information;

[0045] S12. Obtain the reference power for the automatic control of the flexible distribution network according to the communication link matrix and the output power output from the converter ports of each new energy DG;

[0046] S13. Calculate the power command value for each new energy DG to perform droop control according to the reference power;

[0047] S14. Perform droop control on each DG in the flexible distribution network according to the power command value during droop control.

[0048] Optionally, the aforementioned new energy DG includes at least one of the following:

[0049] Energy storage DG;

[0050] Photovoltaic DG;

[0051] Fan DG;

[0052] Gas power generation DG.

[0053] The new energy distributed generation device DG provided by the embodiment of the present invention may include, for example, energy storage power generation, photovoltaic power generation, wind power generation, and gas power generation.

[0054] In the above-mentioned step S11, the resilient distribution network can be modeled by a graph. The basic knowledge of graph theory and the limiting conditions are given. In the island operation mode, the corresponding communication link matrix is generated according to the difference of the Laplacian matrix.

[0055] The topological structure of the resilient distribution network established accordingly can be referred to, for example, Figure 2 as shown, Figure 2 The black dotted line in represents the communication topological connection relationship between DGs; the node structure of the aforementioned resilient distribution network includes 6 endpoints, namely Figure 2 1, 2, 3, 4, 5, 6 in; including 6 new energy DGs, which are respectively Figure 2 DG1, DG2, DG3, DG4, DG5, DG6 in, respectively representing distributed generation devices for primary control; DG1-6 are respectively connected to the resilient distribution network through 1-6 of the above 6 endpoints.

[0056] Among them, the resilient distribution network is connected to the main grid through the circuit breaker (main switch) at node No. 632. Due to the active voltage and frequency support capabilities of primary control, the entire distribution network system can operate either in the grid-connected operation mode or in the island operation mode.

[0057] The resilient distribution network provided by the embodiment of the present invention is a resilient distribution network with multiple new energy DGs distributedly connected, and the structure is relatively complex. Among them, each endpoint has a corresponding load. There is a switch between node 671 and node 692, and its opening and closing with the main switch will greatly change the architecture of the entire system: if the main switch is closed and the switch between node 671 and node 692 is closed, the entire system operates in the grid-connected mode; if the main switch is closed and the switch between node 671 and node 692 is open, then node 692 and node 675 connected to DG5 operate in the island mode, and the rest of the system operates in the grid-connected mode; if the main switch is open and the switch between node 671 and node 692 is closed, the entire system operates in the island mode; if the main switch is open and the switch between node 671 and node 692 is open, the entire system is disconnected into two island systems.

[0058] The communication topology between DGs is fully interconnected under fault-free conditions. When a single-point communication fault occurs between any two DGs, the entire system can still maintain global connectivity, but the connectivity methods are different under different faults, and the faulty line can send a fault signal to the monitoring device (such as uPMU, PMU phasor measurement units).

[0059] The generation of the communication link matrix can be carried out, for example, according to the following steps, including:

[0060] Determine the adjacency matrix and the in-degree matrix according to the topological state of the communication network of the distribution network;

[0061] Obtain the communication link matrix according to the adjacency matrix and the in-degree matrix.

[0062] The aforementioned determination of the adjacency matrix and the in-degree matrix can be carried out in the following manner:

[0063] Model the topological state of the communication network of the distribution network system in the form of a graph to obtain the communication graph G=(V, E, A), where the distributed new energy DG is the node of the communication graph; the edges of the communication graph represent communication links;

[0064] In the above formula, V represents the set of vertices, E represents the set of arcs, and A represents the adjacency matrix. For a non-empty finite set V={v1, v2,..., v N} of N nodes, the set of arcs is defined as where the adjacency matrix Define the in-degree matrix as where

[0065] In one embodiment: the communication link matrix L = D - A, and the sum of all rows of L is equal to zero.

[0066] For the case where there is only one two-way communication link between two nodes, that is, an acyclic graph where the number of edges of the communication graph is equal to the number of nodes, define the communication link matrix as [e1 e2 e3... e n , where e n represents the fault condition of each two-way communication link, with connectivity being 1 and fault being 0.

[0067] Under the above definition, for example, in a distribution network system including three DGs, the generated communication link matrix can be, for example:

[0068]

[0069] The output power of the DG in the power automatic control method of the flexible distribution network provided by the embodiment of the present invention is synchronized with the reference power, and according to the fault type corresponding to the communication link matrix, the output power output by the embodiment of the present invention changes with the change of the communication topology structure.

[0070] When considering the active power control considering the change of the topology structure of the communication network of the distribution network, according to the communication link matrix obtained from the Laplacian matrix, the active power control considering the change of the topology structure of the communication network of the distribution network is designed to synchronize the active power of the new energy DG with the reference active power. According to different fault types, the output of the embodiment of the present invention, that is, the reference active power, changes with the change of the topology structure of the communication network of the distribution network; when considering the reactive power control considering the change of the topology structure of the communication network of the distribution network, according to the communication link matrix obtained from the Laplacian matrix, the reactive power control considering the change of the communication structure is designed to synchronize the reactive power of the new energy DG with the reference reactive power. According to different fault types, the output of the embodiment of the present invention, that is, the reference reactive power, changes with the change of the communication topology structure. It can be realized that in the case of the communication failure of individual new energy DGs, the adjustment of the output power of the embodiment of the present invention is changed, the deviation brought by the primary control is eliminated, and in the case of the distribution network failure, a stable rated power output is still maintained.

[0071] The power automatic control method of the flexible distribution network provided by the embodiment of the present invention, considering the distributed grid power of the flexible distribution network considering the change of the topology structure of the communication network, can ensure the normal execution of the embodiment of the present invention and eliminate the voltage and frequency deviation in the case of the failure of the topology structure of the communication network of the distribution network but without affecting the global connectivity of the system.

[0072] In the above step S12, the reference power is the active reference power (that is, the active power command is issued); according to the communication link matrix and the output power output by the converter ports of each new energy DG, the reference power for the automatic control of the flexible distribution network is obtained, including:

[0073] According to the adjacency matrix, the active power droop coefficient when performing droop control on each new energy DG, the sampled value of the active power output by the converter port of each new energy DG, and the sampled value of the active power output by the new energy DGs adjacent to each new energy DG in the communication graph, the first local domain tracking error of each new energy DG is calculated;

[0074] According to the first local domain tracking error, the reciprocal of the active power secondary control response time is obtained, and the reciprocal of the active power secondary response time is integrated to obtain the active reference power of each new energy DG used for droop control.

[0075] In the case where the output power in the embodiment of the present invention is active power, according to the above communication link matrix, considering the active power control for the topological structure change of the communication network of the distribution network, it is designed to synchronize the active power of the DG with the reference active power. Considering that the primary control adopts droop control, its frequency-active power droop characteristic is shown in the following formula:

[0076] ω i =ω n -m pi P i Formula 1

[0077] Where, ω i is the converter port frequency of the i-th DG, P i is the active power output at the converter port of the i-th DG, m pi is the primary control active frequency droop coefficient, and ω n is the reference frequency input for the primary control.

[0078] Taking the derivative of Formula 1, we can get:

[0079]

[0080] Considering that after the secondary control is applied, the active power of each distributed power source DG can still be distributed according to the required power, that is:

[0081]

[0082] Where, n is the total number of DGs, and P maxi is the rated active power of each DG.

[0083] The calculation process of the active reference power is described below:

[0084] To achieve synchronization, it is assumed that the DGs can communicate with each other through a preset communication graph G. The selection of the auxiliary control is based on the information of each DG itself and the information of its neighbors in the communication graph:

[0085]

[0086] Where, α p is a real variable, and e pi is the local neighborhood tracking error of the i-th DG (i.e., the first local neighborhood tracking error), which is defined as:

[0087]

[0088] Where, a ij is the element in the i-th row and j-th column of the adjacency matrix A, and n i is the adjacent node of the i-th DG on the communication graph.

[0089] Formula Five is written in matrix form as:

[0090] e P = L·δ p Formula Six

[0091] where e P = [e p1 e p2 … e pn T , L is a time-varying Laplacian matrix, and δ p is the power local deviation.

[0092] According to different fault types, the output of the embodiment of the present invention, i.e., the reference active power, varies with the topological structure of the communication network of the distribution network. According to the above formula, in the case where the output power is active power, according to the active power P i and P j output from the converter ports of the DGs, and the active power secondary control formula:

[0093]

[0094] Based on e pi obtain c p , c p is a real number, i.e., the reciprocal of the active power secondary control response time; and then further integrate it through an integral link (s is the integral symbol) to obtain the reference active power P ref of the droop control.

[0095] In the foregoing step S12, if the reference power is the reactive power reference power (i.e., a reactive power command is issued); according to the communication link matrix and the output power output from the converter ports of each new energy DG, obtain the reference power for the automatic control of the resilient distribution network, including:

[0096] Calculate the second local area tracking error of each new energy DG according to the adjacency matrix, the target weight value of the reference power of the new energy DG, the sampled value of the reactive power output from the converter ports of each new energy DG, and the sampled value of the reactive power output from the adjacent new energy DGs of each new energy DG in the communication graph;

[0097] Based on the second local area tracking error, obtain the reciprocal of the reactive power secondary control response time, and integrate the reciprocal of the reactive power secondary response time to obtain the active reference power of each new energy DG used for the droop control.

[0098] ​In the case where the output power is reactive power, according to the above communication link matrix, the active power control considering the topological structure change of the communication network of the distribution network is designed to synchronize the reactive power of the DG with the reference reactive power. Considering that the primary control adopts droop control, its voltage-reactive power droop characteristic is shown in the following formula:

[0099]

[0100] where, v odi is the d-axis voltage of the converter port of the i-th DG, v oqi is the q-axis voltage of the converter port of the i-th DG, n Qi is the primary control reactive voltage droop coefficient, Q i is the reactive power output of the converter port of the i-th DG, V n is the reference voltage input for the primary control. Taking the derivative of the d-axis voltage phase shift of formula seven gives:

[0101]

[0102] The selection of the auxiliary control is based on the information of each DG itself and the information of its neighbors in the communication graph, as shown in the following formula:

[0103]

[0104] where, α Q is a real variable, e Qi is the local area tracking error (the second local area tracking error) of the i-th DG, defined as:

[0105]

[0106] where, a ij is the element in the i-th row and j-th column of the adjacency matrix A, n i is the adjacent node of the i-th DG on the communication graph, Q ref is the reference reactive power, and the gain g i ≥0 is the weight of the i-th DG to the reference value. Formula ten written in matrix form is:

[0107] e Q =(L + G)·δ Q Formula eleven

[0108] where, e = [e Q1 e Q2 L e Qn T , L is a time-varying Laplacian matrix, is a diagonal matrix about the gain g i , and δ Q is the local deviation of reactive power.​

[0109] According to different fault types, the output of the embodiments of the present invention, i.e., the reference reactive power, varies with the topological structure of the communication network of the distribution network.

[0110] In the foregoing step S14, according to the power during droop control, droop control is performed on each new energy DG in the flexible distribution network so that each DG reaches the corresponding reference power, including:

[0111] According to the active reference power of each new energy DG carried in the issued active power command, perform primary control on each new energy DG. The primary control uses droop control to control the output frequency and output voltage of each new energy DG;

[0112] And according to the reactive reference power of each energy DG carried in the issued reactive power command, perform primary control on the new energy DG. The primary control uses droop control to control the output frequency and output voltage of each new energy DG.

[0113] In specific implementation, the master control device of the distribution network can issue an active power command and a reactive power command simultaneously to control the voltage and frequency of each DG device until the network of the entire distribution network reaches balance and the output power consistent with the reference power is achieved.

[0114] Referring to Figure 5 the flowchart shown, Qj is the sampled value of the reactive power output by the DG of the adjacent node, Pj is the sampled value of the active power of the DG of the adjacent node, and C is calculated by inputting into the formula for secondary control. Q and C P , and then integrated to obtain the reactive power command value Q cmd , and the active power command value P cmd ; according to the active power command value and the reactive power command value, perform droop control to control the voltage and frequency of the DG, etc.

[0115] Based on the same inventive concept, the embodiments of the present invention further provide a power automatic control device for a flexible distribution network, and its structural block diagram is as shown in Figure 4 shown. The device is applicable to a flexible distribution network, and the flexible distribution network includes multiple endpoints; multiple new energy distributed generation devices DG, which are respectively connected to the multiple endpoints, including:

[0116] An acquisition module 41, configured to acquire the topological information of the communication network of the current flexible distribution network, and generate a communication link matrix corresponding to the current flexible distribution network according to the topological information;

[0117] A calculation module 42 is configured to obtain the reference power for the automatic control of the resilient distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG; and calculate the power for droop control of each new energy DG according to the reference power.

[0118] A control module 43 is configured to perform droop control on each DG in the resilient distribution network according to the power during droop control, so that each DG reaches the corresponding reference power.

[0119] Based on the same inventive concept, an embodiment of the present invention further provides a control device for a resilient distribution network, including: a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, it implements the power automatic control method of the resilient distribution network.

[0120] Based on the same inventive concept, an embodiment of the present invention further provides a power control device, the structural block diagram of which is as Figure 3 shown, including: a processor 600; and a memory 610 connected to the processor 600 through a bus interface. The memory 610 is used to store the programs and data used by the processor 600 when performing operations. The processor 600 calls and executes the programs and data stored in the memory 610.

[0121] Specifically, the processor 600 performs the following processes:

[0122] Obtain the topology information of the communication network of the current resilient distribution network, and generate a communication link matrix corresponding to the current resilient distribution network according to the topology information;

[0123] Obtain the reference power for the automatic control of the resilient distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG;

[0124] Calculate the power command value for droop control of each new energy DG according to the reference power;

[0125] Perform droop control on each DG in the resilient distribution network according to the power command value during droop control.

[0126] The bus architecture may include any number of interconnected buses and bridges, with various circuits represented by one or more processors represented by processor 600 and memory represented by memory 610 linked together. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and thus will not be further described herein. The bus interface provides a user interface 630. The transceiver 620 may be multiple components, i.e., including a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium. The processor 600 is responsible for managing the bus architecture and general processing, and the memory 610 may store data used by the processor 600 when performing operations.

[0127] Based on the same inventive concept, an embodiment of the present invention also provides a computer-readable storage medium storing a computer program, which when executed by a processor implements a method for automatic power control of an elastic distribution network.

[0128] Regarding the automatic power control device for the elastic distribution network in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment related to the method and will not be elaborated herein.

[0129] The present invention discloses a method for automatic power control of an elastic distribution network. The method is applicable to an elastic distribution network, which includes multiple endpoints; multiple new energy distributed generation devices DG, respectively connected to the multiple endpoints. The method includes: obtaining the topology information of the communication network of the current elastic distribution network, and generating a communication link matrix corresponding to the current elastic distribution network according to the topology information; obtaining the reference power for automatic control of the elastic distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG; calculating the power for droop control of each new energy DG according to the reference power; and performing droop control on each DG in the elastic distribution network according to the power during the droop control. Embodiments of the present invention can achieve full communication between the communication topologies among new energy DGs without faults, and when a single-point fault occurs between any two new energy DGs, the entire power distribution system can still maintain global connectivity.

[0130] The present invention discloses a method for automatic power control of an elastic distribution network. The method is applicable to an elastic distribution network, which includes multiple endpoints; multiple new energy distributed generation devices DG, which are respectively connected to the multiple endpoints. The method includes: obtaining the topological information of the communication network of the current elastic distribution network, and generating a communication link matrix corresponding to the current elastic distribution network according to the topological information; obtaining the reference power for automatic control of the elastic distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG; calculating the power for droop control of each new energy DG according to the reference power; and performing droop control on each DG in the elastic distribution network according to the power during the droop control. The embodiments of the present invention can achieve full communication between the communication topologies of new energy DGs without faults. When a single-point fault occurs between any two new energy DGs, the entire distribution system can still maintain global connectivity. Moreover, when a network fault occurs and the network topology changes, the output power of the distribution network can still be adaptively adjusted to reach the preset power through droop power control, compensating for the power loss of the faulty line.

[0131] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer-usable program code.

[0132] The present invention is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, and the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the functions specified in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0133] These computer program instructions can 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 generate a manufactured article including an instruction device, and the instruction device implements the functions specified in Figure 1 one process or multiple processes and / or blocks Figure 1The functions specified in one or more boxes.

[0134] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide for implementing steps of the functions specified in one Figure 1 one process or more processes and / or boxes Figure 1 step of the functions specified in one box or more boxes.

[0135] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. A method for automatic power control of an elastic distribution network, characterized in that The method is applicable to the resilient distribution network, and the resilient distribution network includes multiple endpoints; A plurality of new energy distributed generation devices DG are respectively connected to the multiple endpoints, and the method includes: Obtaining the topology information of the communication network of the current resilient distribution network, and generating a communication link matrix corresponding to the current resilient distribution network according to the topology information; Obtaining the reference power for the automatic control of the resilient distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG; Calculating the power command value for droop control of each new energy DG according to the reference power; Performing droop control on each DG in the resilient distribution network according to the power command value during droop control.

2. The method according to claim 1, wherein Detecting the topology information of the communication network of the current resilient distribution network, and generating a communication link matrix corresponding to the current resilient distribution network according to the topology information, including: Determining the adjacency matrix and the in-degree matrix according to the topology state of the communication network of the distribution network; Obtaining the communication link matrix according to the adjacency matrix and the in-degree matrix.

3. The method according to claim 2, characterized in that, Determining the adjacency matrix and the in-degree matrix according to the topology state of the communication network of the distribution network, including: Modeling the topology state of the communication network of the distribution network system in the form of a graph to obtain a communication graph G=(V, E, A), where the distributed new energy DG is the node of the communication graph; the edges of the communication graph represent communication links; In the above formula, V represents the set of vertices, E represents the set of arcs, and A represents the adjacency matrix. For a non-empty finite set V = {v1, v2,..., v N}, the set of arcs is defined as Adjacency matrix Define the in-degree matrix as where 4. The method according to claim 3, characterized in that Obtaining the communication link matrix according to the adjacency matrix and the in-degree matrix, including: Defining the communication link matrix L = D - A, and the sum of all rows of L is equal to zero.

5. The method according to claim 1, characterized in that The reference power is the active reference power; the obtaining the reference power for the automatic control of the resilient distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG includes: Calculating the first local area tracking error of each new energy DG according to the adjacency matrix, the active power droop coefficient during droop control of each new energy DG, the sampled value of the active power output by the converter port of each new energy DG, and the sampled value of the active power output by the new energy DG adjacent to each new energy DG in the communication graph; Obtaining the reciprocal of the active power secondary control response time according to the first local area tracking error, and integrating the reciprocal of the active power secondary response time to obtain the active reference power of each new energy DG used for droop control.

6. The method according to claim 1, wherein The reference power is the reactive reference power; the obtaining the reference power for the automatic control of the resilient distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG includes: Calculating the second local area tracking error of each new energy DG according to the adjacency matrix, the target weight value of the reference power of the new energy DG, the sampled value of the reactive power output by the converter port of each new energy DG, and the sampled value of the reactive power output by the new energy DG adjacent to each new energy DG in the communication graph; Based on the second local area tracking error, the reciprocal of the secondary control response time of reactive power is obtained, and the reciprocal of the secondary response time of reactive power is integrated to obtain the active reference power of each new energy DG used for droop control.

7. The method according to claim 1, wherein Based on the power command value during the droop control, droop control is performed on each new energy DG in the flexible distribution network, including: According to the active power command values of each new energy DG carried in the issued active power command, primary control is performed on each new energy DG. The primary control uses droop control to control the output frequency and output voltage of each new energy DG; And according to the reactive power command values of each energy DG carried in the issued reactive power command, primary control is performed on the new energy DG. The primary control uses droop control to control the output frequency and output voltage of each new energy DG.

8. An automatic power control device for an elastic distribution network, characterized in that, The device is applicable to the flexible distribution network, and the flexible distribution network includes multiple endpoints; Multiple new energy distributed generation devices DG are respectively connected to multiple endpoints, including: An acquisition module, configured to acquire the topology information of the communication network of the current flexible distribution network, and generate a communication link matrix corresponding to the current flexible distribution network according to the topology information; A calculation module, configured to obtain the reference power for automatic control of the flexible distribution network according to the communication link matrix and the output power output by the converter ports of each new energy DG; and calculate the power command value for droop control of each new energy DG according to the reference power; A control module, configured to perform droop control on each DG in the flexible distribution network according to the power command value during the droop control, so that each DG reaches the corresponding reference power.

9. A control device for an elastic distribution network, characterized in that, Including: A memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the power automatic control method of the flexible distribution network according to any one of claims 1-7 is implemented.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and when the computer program is executed by the processor, the power automatic control method of the flexible distribution network according to any one of claims 1-7 is implemented.

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