Method and device for determining node frequency change rate, medium and terminal

Abstract

The invention discloses a node frequency change rate determination method and device, a medium and a terminal, relates to the technical field of power system frequency adjustment, and mainly aims to solve the problem that existing system frequency adjustment cannot meet the system frequency adjustment requirement of a double-high power system. Comprising the following steps: when frequency disturbance in a generator set line is monitored, acquiring a voltage change value and a current change value of a disturbance node, an impedance distribution parameter, a generator inertia value of each generator and a length value of a first transmission line between the generators; calculating a node disturbed power value at the target node according to the branch current change value at the target node, the node impedance value and the disturbance node voltage change value; based on a node inertia distribution model, determining a node inertia value at the target node according to a second transmission line length value from the target node to each generator; and determining a node frequency change rate at the target node according to the node disturbed power value and the node inertia value.

Description

Technical Field

[0001] The present application relates to the technical field of power system frequency regulation, and in particular to a method and device, medium, and terminal for determining a node frequency change rate. Background Art

[0002] With the access of high proportion of new energy and power electronic equipment, the traditional power system dominated by synchronous generators has gradually transformed into a new energy power system with high power electronics in the source, network, load, storage and other links, referred to as the "double high power system", that is, a power system with a high proportion of renewable energy and a high proportion of power electronic equipment. In order to ensure the frequency security of the double high power system, it is necessary to adjust the system frequency according to the frequency change characteristics in the system.

[0003] In the prior art, the disturbance power is usually distributed to each synchronous generator node according to the synchronous power coefficient to obtain the disturbance power value at the generator end, and then the swing equation is used to calculate the generator end frequency change rate based on the known generator end disturbance power value and the generator's own inertia, so as to adjust the system frequency based on the generator end frequency change rate.

[0004] However, in the dual-high power system, due to the changes in the dynamic characteristics of the system frequency, the frequency dynamic characteristics of each node are obviously heterogeneous. The system frequency adjustment based only on the frequency change rate of the generator end and the frequency change rate of the disturbance node cannot meet the system frequency adjustment needs of the dual-high power system, resulting in the inability to ensure the system frequency safety of the dual-high power system. Summary of the invention

[0005] In view of this, the present application provides a method and device, medium, and terminal for determining the node frequency change rate. The main purpose is to solve the problem that the existing system frequency adjustment based on the frequency change rate of the generator end and the frequency change rate of the disturbance node cannot meet the system frequency adjustment requirements of the dual-high power system, resulting in the inability to ensure the system frequency safety of the dual-high power system.

[0006] According to one aspect of the present application, a method for determining a node frequency change rate is provided, comprising:

[0007] When a frequency disturbance is detected in the generator set line, a disturbance node voltage change value and a disturbance node current change value at the disturbance node, an impedance distribution parameter of the generator set line, a generator inertia value of each generator in the generator set line, and a first transmission line length value between the generators are obtained;

[0008] Calculate the node disturbed power value at the target node according to the branch current change value and the node impedance value at the target node and the disturbance node voltage change value, wherein the node impedance value is determined according to the impedance distribution parameter, and the branch current change value is obtained by distributing the disturbance node current change value to each branch line included in the generator unit line based on the impedance distribution parameter;

[0009] Based on the node inertia distribution model of the generator set line, the node inertia value at the target node is determined according to the second transmission line length value from the target node to each of the generators, wherein the node inertia distribution model is pre-constructed according to the inertia values ​​of each of the generators and the first transmission line length value;

[0010] The node frequency change rate at the target node is determined according to the node disturbed power value and the node inertia value.

[0011] Preferably, calculating the node disturbed power value at the target node according to the branch current change value and the node impedance value at the target node and the disturbance node voltage change value includes:

[0012] Based on the impedance distribution parameter, the disturbance node current change value is distributed to each branch line included in the generator unit line to obtain the branch current change value of each branch line;

[0013] Based on the impedance distribution parameter, each impedance value between the disturbance node and the target node is obtained, and the sum of each impedance value is determined as the node impedance value at the target node;

[0014] Determine the product of the node impedance value and the branch current change value of the branch line where the target node is located as the disturbance power propagation voltage drop value at the target node;

[0015] Determine the difference between the disturbance node voltage change value and the disturbance power propagation voltage drop value as the node voltage change value at the target node;

[0016] The product of the node voltage change value and the branch current change value is determined as the node disturbed power value at the target node.

[0017] Preferably, the method of distributing the disturbance node current change value to each branch line included in the generator set line based on the impedance distribution parameter to obtain the branch current change value of each branch line includes:

[0018] Based on the impedance distribution parameter, calculating the branch impedance value of each branch line included in the generator set line, and calculating the proportion of each branch impedance value to the total impedance value of the generator set line;

[0019] Taking each of the branch routes as a target branch route one by one;

[0020] Determine the product of the sum of the proportions corresponding to other branch lines except the target branch line and the disturbance node current change value as the branch current change value of the target branch line;

[0021] The branch current change value of each branch line is obtained.

[0022] Preferably, before determining the node inertia value at the target node based on the node inertia distribution model of the generator set line according to the second transmission line length value from the target node to each of the generators, the method further comprises:

[0023] According to the generator inertia value of each generator and the length value of the first transmission line, a corresponding sub-node inertia distribution model is constructed based on a Gaussian distribution function;

[0024] The sub-node inertia distribution models of the generators in operation are added together to obtain the node inertia distribution model of the generator set line.

[0025] Preferably, determining the node frequency change rate at the target node according to the node disturbed power value and the node inertia value includes:

[0026] The quotient of the node disturbed power value and the node inertia value of a preset multiple is determined as the node frequency change rate at the target node.

[0027] Preferably, the method further comprises:

[0028] Selecting a plurality of points in the generator set circuit as preset nodes, and calculating the node frequency change rate at each of the preset nodes;

[0029] The system frequency of the generator set circuit is adjusted according to the frequency change rate of each node.

[0030] Preferably, the subnode inertia distribution model is expressed as the following formula:

[0031]

[0032] Among them, H m,i (x i ) represents the generator G m At node xi The node inertia at m,i Indicates the parameter, H m Represents the generator G m The generator inertia value, c m,i Indicates the first transmission line length value.

[0033] According to another aspect of the present application, a device for determining a node frequency change rate is provided, comprising:

[0034] A data acquisition module is used to acquire a disturbance node voltage change value and a disturbance node current change value at a disturbance node, an impedance distribution parameter of the generator unit line, a generator inertia value of each generator in the generator unit line, and a first transmission line length value between generators when a frequency disturbance is detected in the generator unit line;

[0035] A node disturbed power value calculation module, used to calculate the node disturbed power value at the target node according to the branch current change value and the node impedance value at the target node and the disturbance node voltage change value, wherein the node impedance value is determined according to the impedance distribution parameter, and the branch current change value is obtained by distributing the disturbance node current change value to each branch line included in the generator unit line based on the impedance distribution parameter;

[0036] a node inertia value determination module, configured to determine the node inertia value at the target node based on a node inertia distribution model of the generator set line and according to a second transmission line length value from the target node to each of the generators, wherein the node inertia distribution model is pre-constructed according to the inertia values ​​of each of the generators and the first transmission line length value;

[0037] The node frequency change rate determination module is used to determine the node frequency change rate at the target node according to the node disturbed power value and the node inertia value.

[0038] Preferably, the node disturbance power value calculation module is used to:

[0039] Based on the impedance distribution parameter, the disturbance node current change value is distributed to each branch line included in the generator unit line to obtain the branch current change value of each branch line;

[0040] Based on the impedance distribution parameter, each impedance value between the disturbance node and the target node is obtained, and the sum of each impedance value is determined as the node impedance value at the target node;

[0041] Determine the product of the node impedance value and the branch current change value of the branch line where the target node is located as the disturbance power propagation voltage drop value at the target node;

[0042] Determine the difference between the disturbance node voltage change value and the disturbance power propagation voltage drop value as the node voltage change value at the target node;

[0043] The product of the node voltage change value and the branch current change value is determined as the node disturbed power value at the target node.

[0044] Preferably, the node disturbed power value calculation module is further used for:

[0045] Based on the impedance distribution parameter, calculating the branch impedance value of each branch line included in the generator set line, and calculating the proportion of each branch impedance value to the total impedance value of the generator set line;

[0046] Taking each of the branch routes as a target branch route one by one;

[0047] Determine the product of the sum of the proportions corresponding to other branch lines except the target branch line and the disturbance node current change value as the branch current change value of the target branch line;

[0048] The branch current change value of each branch line is obtained.

[0049] Preferably, before the node inertia value determination module, the device further includes a node inertia distribution model construction module, which is used to:

[0050] According to the generator inertia value of each generator and the length value of the first transmission line, a corresponding sub-node inertia distribution model is constructed based on a Gaussian distribution function;

[0051] The sub-node inertia distribution models of the generators in operation are added together to obtain the node inertia distribution model of the generator set line.

[0052] Preferably, the node frequency change rate determination module is used to:

[0053] The quotient of the node disturbed power value and the node inertia value of a preset multiple is determined as the node frequency change rate at the target node.

[0054] Preferably, the device further comprises a frequency adjustment module, which is used to:

[0055] Selecting a plurality of points in the generator set circuit as preset nodes, and calculating the node frequency change rate at each of the preset nodes;

[0056] The system frequency of the generator set circuit is adjusted according to the frequency change rate of each node.

[0057] Preferably, the subnode inertia distribution model is expressed as the following formula:

[0058]

[0059] Among them, H m,i (x i ) represents the generator G m At node x i The node inertia at m,i Indicates the parameter, H m Indicates the generator G m The generator inertia value, c m,i Indicates the first transmission line length value.

[0060] According to another aspect of the present application, a storage medium is provided, wherein at least one executable instruction is stored in the storage medium, and the executable instruction enables a processor to perform operations corresponding to the above-mentioned method for determining the node frequency change rate.

[0061] According to another aspect of the present application, a terminal is provided, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other through the communication bus;

[0062] The memory is used to store at least one executable instruction, and the executable instruction enables the processor to execute operations corresponding to the above-mentioned method for determining the node frequency change rate.

[0063] By means of the above technical solution, the technical solution provided by the embodiment of the present application has at least the following advantages:

[0064] The present application provides a method and device for determining a node frequency change rate, a medium, and a terminal. First, when a frequency disturbance is detected in a generator unit line, a disturbance node voltage change value and a disturbance node current change value at the disturbance node, an impedance distribution parameter of the generator unit line, a generator inertia value of each generator in the generator unit line, and a first transmission line length value between generators are obtained; secondly, according to the branch current change value and the node impedance value at the target node, and the disturbance node voltage change value, the node disturbed power value at the target node is calculated, and the node impedance value is determined according to the impedance distribution parameter. The branch current change value is obtained by distributing the disturbance node current change value to each branch line included in the generator set line based on the impedance distribution parameter; thirdly, based on the node inertia distribution model of the generator set line, according to the second transmission line length value from the target node to each of the generators, the node inertia value at the target node is determined, and the node inertia distribution model is pre-constructed according to the inertia values ​​of each of the generators and the first transmission line length value; finally, according to the node disturbed power value and the node inertia value, the node frequency change rate at the target node is determined. Compared with the prior art, the embodiment of the present application distributes the disturbance node current change value to each branch line based on the impedance distribution parameter to obtain the branch current change value, and calculates the node disturbed power value of each node in combination with the disturbance node voltage change value. Since the loss of the disturbance power on the line and the difference in the impact of the disturbance on each node are fully considered, it is more suitable for the characteristics of the dual-high power system; further, the node inertia value is calculated using a pre-established node inertia distribution model. Since the model describes the distribution of the node inertia value in the line with the node position, the node inertia value of any node can be obtained according to the node position information, and then the node frequency change rate at any node can be obtained to meet the demand for system frequency regulation according to the node frequency change rate of any node, meet the system frequency regulation demand of the dual-high power system, and effectively improve the system frequency safety of the dual-high power system.

[0065] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0067] Figure 1 A flow chart of a method for determining a node frequency change rate provided by an embodiment of the present application is shown;

[0068] Figure 2 A unit-line parameter model diagram provided in an embodiment of the present application is shown;

[0069] Figure 3 A flow chart of another method for determining a node frequency change rate provided in an embodiment of the present application is shown;

[0070] Figure 4 The node inertia distribution model curve of the dual motor system provided by the embodiment of the present application is shown;

[0071] Figure 5 A block diagram of a device for determining a node frequency change rate provided by an embodiment of the present application is shown;

[0072] Figure 6 A schematic diagram of the structure of a terminal provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0073] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying 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 to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0074] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0075] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0076] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0077] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0078] The embodiments of the present application can be applied to computer systems / servers, which can operate with many other general or special computing system environments or configurations. Examples of well-known computing systems, environments and / or configurations suitable for use with computer systems / servers include, but are not limited to: personal computer systems, server computer systems, thin clients, thick clients, handheld or laptop devices, microprocessor-based systems, set-top boxes, programmable consumer electronics, network personal computers, small computer systems, large computer systems, and distributed cloud computing technology environments including any of the above systems, etc.

[0079] Computer systems / servers may be described in the general context of computer system executable instructions (such as program modules) executed by a computer system. In general, program modules may include routines, programs, object programs, components, logic, data structures, etc., which perform specific tasks or implement specific abstract data types. Computer systems / servers may be implemented in a distributed cloud computing environment where tasks are performed by remote processing devices linked through a communication network. In a distributed cloud computing environment, program modules may be located on local or remote computing system storage media including storage devices.

[0080] The present application embodiment provides a method for determining a node frequency change rate, such as Figure 1 As shown, the method includes:

[0081] 101. When a frequency disturbance is detected in the generator set line, obtain the disturbance node voltage change value and the disturbance node current change value at the disturbance node, the impedance distribution parameter of the generator set line, the generator inertia value of each generator in the generator set line, and the first transmission line length value between the generators.

[0082] Among them, the disturbance node voltage change value is used to characterize the voltage change value caused by the frequency disturbance at the disturbance node, which can be directly measured by a measuring instrument; the disturbance node current change value is used to characterize the current change value caused by the frequency disturbance at the disturbance node, which can be directly measured by a measuring instrument; the impedance distribution parameter is used to record the impedance distribution in the generator unit line, which can be recorded using the unit-line parameter model diagram, such as Figure 2 As shown in the figure, X′ d1 , X T1 , X 2k , X k3 , X T2 , X′ d2All represent impedance; the generator inertia value is an inherent parameter of the generator and can be directly obtained; the first transmission line length value is used to characterize the transmission line length between any two generators. In the embodiment of the present application, the current execution end can be a system frequency adjustment module of the generator set line.

[0083] 102. Calculate the node disturbed power value at the target node according to the branch current change value at the target node, the node impedance value, and the disturbance node voltage change value.

[0084] Among them, the node impedance value is determined according to the impedance distribution parameter, and the node impedance value is the total impedance contained between the disturbance node and the node. It can be understood that the impedance in the line is analogous to the resistance, and the total impedance contained between the disturbance node and the node can be obtained by summing up all the impedance values ​​contained between the disturbance node and the node; the branch current change value is based on the impedance distribution parameter, and the disturbance node current change value is distributed to each branch line contained in the generator unit line. Specifically, the disturbance node current change value is based on the proportion of the branch impedance value of each branch line to the total impedance value of the motor unit line. In the embodiment of the present application, the node disturbed power value at the target node is calculated according to the branch current change value and the node impedance value at the target node, combined with the disturbance node voltage change value. Since the loss of the disturbance power on the line and the difference in the influence of the disturbance on each node are fully considered, it is more suitable for the characteristics of the dual-high power system.

[0085] 103. Based on the node inertia distribution model of the generator unit line, the node inertia value at the target node is determined according to the second transmission line length value from the target node to each generator.

[0086] Among them, the node inertia distribution model is pre-constructed according to the inertia values ​​of each generator and the first transmission line length value, and is used to characterize the distribution of the generator inertia with the node position in the generator unit line. It should be noted that the node inertia distribution model of the generator unit line is obtained by adding the sub-node inertia distribution models corresponding to all the generators in operation contained in the generator unit line; the second transmission line length value is used to characterize the transmission line length value from the target node to the generator. It can be understood that the node inertia value at the target node can be determined by substituting the second transmission line length value into the node inertia distribution model. In the embodiment of the present application, the node inertia value is calculated using the pre-established node inertia distribution model. Since the model describes the distribution of the generator inertia with the node position in the generator unit line, the node inertia value of any node can be obtained based on the node position information.

[0087] 104. Determine the node frequency change rate at the target node according to the node disturbed power value and the node inertia value.

[0088] Specifically, the quotient between the node disturbed power value and several times the node inertia value can be determined as the node frequency change rate. In the embodiment of the present application, the node frequency change rate at any node is determined according to the node disturbed power value and the node inertia value at any node, which meets the demand for system frequency regulation according to the node frequency change rate of any node, meets the system frequency regulation demand of the dual-high power system, and effectively improves the system frequency safety of the dual-high power system.

[0089] Compared with the prior art, the embodiment of the present application distributes the disturbance node current change value to each branch line based on the impedance distribution parameter to obtain the branch current change value, and calculates the node disturbed power value of each node in combination with the disturbance node voltage change value. Since the loss of the disturbance power on the line and the difference in the impact of the disturbance on each node are fully considered, it is more suitable for the characteristics of the dual-high power system; further, the node inertia value is calculated using a pre-established node inertia distribution model. Since the model describes the distribution of the node inertia value in the line with the node position, the node inertia value of any node can be obtained according to the node position information, and then the node frequency change rate at any node can be obtained to meet the demand for system frequency regulation according to the node frequency change rate of any node, meet the system frequency regulation demand of the dual-high power system, and effectively improve the system frequency safety of the dual-high power system.

[0090] The present application embodiment provides another method for determining the node frequency change rate, such as Figure 3 As shown, the method includes:

[0091] 201. When a frequency disturbance is detected in the generator set line, a disturbance node voltage change value and a disturbance node current change value at the disturbance node, an impedance distribution parameter of the generator set line, a generator inertia value of each generator in the generator set line, and a first transmission line length value between the generators are obtained.

[0092] In an embodiment of the present application, when a frequency disturbance is monitored in the generator unit line, a measuring instrument is used to measure the voltage change value of the disturbance node and the current change value of the disturbance node, and the impedance distribution parameter, the generator inertia value, and the first transmission line length value are obtained from the data.

[0093] 202. Based on the impedance distribution parameter, the disturbance node current change value is distributed to each branch line included in the generator unit line to obtain the branch current change value of each branch line.

[0094] Specifically, first, based on the impedance distribution parameters, the branch impedance values ​​of each branch line included in the generator unit line are calculated, and the proportion of each branch impedance value to the total impedance value of the generator unit line is calculated. Figure 2 Taking the impedance distribution parameters recorded in the unit-line parameter model diagram as an example, point k represents the disturbance node. The frequency disturbance occurring at the disturbance node k will propagate from point k to the left and right directions. The left and right directions can be regarded as two branches. The total impedance value of the generator unit line is X′ d1 , X T1 , X 2k , X k3 , X T2 , X′ d2 The branch impedance of the left branch is X′ d1 , X T1 , X 2k The ratio of the branch impedance value of the left branch to the total impedance value of the generator unit line is X′ d1 , X T1 , X 2k The sum of d1 , X T1 , X 2k , X k3 , X T2 , X′ d2 The quotient of the sum of the values, the branch impedance value of the right branch is X k3 , X T2 , X′ d2 The ratio of the branch impedance value of the right branch to the total impedance value of the generator unit line is X k3 , X T2 , X′ d2 The sum of d1 , X T1 , X 2k , X k3 , X T2 , X′ d2 Further, each branch line is taken as the target branch line one by one, and the product of the sum of the proportions corresponding to the other branch lines except the target branch line and the disturbance node current change value is determined as the branch current change value of the target branch line, that is,

[0095]

[0096] Among them, ΔI 1 Indicates the branch current change value of the left branch line, ΔI 2 It represents the branch current change value of the right branch line, and ΔI represents the disturbance node current change value.

[0097] Thus, the branch current change value of each branch line is obtained.

[0098] 203. Based on the impedance distribution parameter, obtain each impedance value between the disturbance node and the target node, and determine the sum of each impedance value as the node impedance value at the target node.

[0099] For example, the node impedance value at node 1 in the figure is X T1 , X 2k The node impedance at node 2 is X 2k wait.

[0100] 204. Calculate the node disturbed power value at the target node according to the branch current change value at the target node, the node impedance value, and the disturbance node voltage change value.

[0101] Specifically, the product of the node impedance value and the branch current change value of the branch line where the target node is located is determined as the disturbance power propagation voltage drop value at the target node, which can be expressed as the following formula:

[0102]

[0103] in, represents the disturbance power propagation voltage drop value at node i, ΔI i Indicates the branch current change value of the branch line where node i is located, Z ik Represents the node impedance value at node i.

[0104] Furthermore, the difference between the disturbance node voltage change value and the disturbance power propagation voltage drop value is determined as the node voltage change value at the target node, which can be expressed as the following formula:

[0105]

[0106] in, Indicates the node voltage change value at node i, ΔU k Indicates the voltage change value of the disturbance node.

[0107] Finally, the product of the node voltage change value and the branch current change value is determined as the node disturbed power value at the target node, which can be expressed as the following formula:

[0108]

[0109] Among them, ΔP i Represents the node disturbed power value at node i.

[0110] 205. Construct a node inertia distribution model for the generator unit line.

[0111] Specifically, according to the generator inertia value of each generator and the length value of the first transmission line, a corresponding sub-node inertia distribution model is constructed based on the Gaussian distribution function.

[0112]

[0113] Among them, H m,i (x i ) represents the generator G m The nodal inertia at node i, a m,i Indicates the parameter, H m Represents the generator G m The generator inertia value, c m,i represents the first transmission line length value, x i Represents node i to generator G m The second transmission line length value.

[0114] It should be noted that, from the non-uniformity of electromechanical wave propagation, when the disturbance propagates to the vicinity of the generator node, the inertia has a significant impact on it, and when it is far away from the generator node, the inertia has a weak impact on it. Therefore, the distribution of the generator inertia on the remaining connected nodes is weakened from near to far. From this analysis, it can be obtained that the scope of the generator inertia is distributed with the distance of the line 6, and the distribution on the line is continuous. Based on this, the generator inertia can be processed on the line according to the Gaussian function distribution.

[0115] 206. Add the sub-node inertia distribution models of the generators in operation to obtain a node inertia distribution model of the generator unit line.

[0116] For example, taking a dual-motor system as an example, the node inertia distribution model can be expressed as the following formula:

[0117] H i (x i )=αH m，i (x i )+βH g，i (x i ),

[0118] Among them, H i (x i ) represents the node inertia value at node i, H m，i (x i ) represents the generator G m The inertia value of the child node at node i, H g，i (x i ) represents the generator G gThe sub-node inertia values, α and β, at node i represent the operating status of the generator, including two values: 0 and 1. When the value is 0, it means that the generator is in the exiting operating state, and when the value is 1, it means that the generator is in the starting operating state.

[0119] The node inertia distribution model curve of the dual-motor system is as follows: Figure 4 shown.

[0120] 207. Determine the node frequency change rate at the target node according to the node disturbed power value and the node inertia value.

[0121] Specifically, the quotient of the node disturbed power value and the node inertia value of a preset multiple is determined as the node frequency change rate at the target node.

[0122] Preferably, the preset multiple may be 2 times.

[0123] For example, taking a dual-motor system as an example, the node frequency change rate at the target node can be expressed as the following formula:

[0124]

[0125] in, represents the distribution of node frequency change rate, H i Indicates the node inertia value, H g Indicates the generator G g The generator inertia value, x i -b i,g Represents node i to generator G g The second transmission line length value.

[0126] 208. Select multiple points in the generator unit line as preset nodes, and calculate the node frequency change rate at each preset node; and adjust the system frequency of the generator unit line according to the frequency change rate of each node.

[0127] It should be noted that the number of preset nodes can be selected according to the actual adjustment accuracy. For example, when the adjustment accuracy is high, a larger number of points can be selected as preset nodes. When the adjustment accuracy is low, a smaller number of points can be selected as preset nodes. Optionally, the quotient between the distribution of the node disturbed power value and the distribution of the node inertia value can be determined as the distribution of the node frequency change rate, and the system frequency is adjusted according to the distribution of the node frequency change rate. At this time, the adjustment accuracy is the highest and the effect is the best.

[0128] The present application provides a method for determining a node frequency change rate. First, when a frequency disturbance is detected in a generator unit line, a disturbance node voltage change value and a disturbance node current change value at a disturbance node, an impedance distribution parameter of the generator unit line, a generator inertia value of each generator in the generator unit line, and a first transmission line length value between generators are obtained; secondly, according to a branch current change value and a node impedance value at a target node, and a disturbance node voltage change value, a node disturbed power value at the target node is calculated, wherein the node impedance value is determined according to the impedance distribution parameter, and the branch current change value and the node impedance value at the target node are determined according to the impedance distribution parameter. The line current change value is obtained by distributing the disturbance node current change value to each branch line included in the generator set line based on the impedance distribution parameter; thirdly, based on the node inertia distribution model of the generator set line, according to the second transmission line length value from the target node to each of the generators, the node inertia value at the target node is determined, and the node inertia distribution model is pre-constructed according to the inertia values ​​of each of the generators and the first transmission line length value; finally, according to the node disturbed power value and the node inertia value, the node frequency change rate at the target node is determined. Compared with the prior art, the embodiment of the present application distributes the disturbance node current change value to each branch line based on the impedance distribution parameter to obtain the branch current change value, and calculates the node disturbed power value of each node in combination with the disturbance node voltage change value. Since the loss of the disturbance power on the line and the difference in the impact of the disturbance on each node are fully considered, it is more suitable for the characteristics of the dual-high power system; further, the node inertia value is calculated using a pre-established node inertia distribution model. Since the model describes the distribution of the node inertia value in the line with the node position, the node inertia value of any node can be obtained according to the node position information, and then the node frequency change rate at any node can be obtained to meet the demand for system frequency regulation according to the node frequency change rate of any node, meet the system frequency regulation demand of the dual-high power system, and effectively improve the system frequency safety of the dual-high power system.

[0129] Furthermore, as a response to the above Figure 1 In order to realize the method shown in the figure, the embodiment of the present application provides a device for determining the node frequency change rate, such as Figure 5 As shown, the device comprises:

[0130] Data acquisition module 31, node disturbance power value calculation module 32, node inertia value determination module 33, node frequency change rate determination module 34;

[0131] A data acquisition module 31, configured to obtain a disturbance node voltage change value and a disturbance node current change value at a disturbance node, impedance distribution parameters of the generator unit line, generator inertia values of each generator in the generator unit line, and a first transmission line length value between generators when a frequency disturbance occurs in the generator unit line;

[0132] A node disturbed power value calculation module 32, configured to calculate a node disturbed power value at the target node according to a branch current change value at the target node, a node impedance value, and the disturbance node voltage change value, where the node impedance value is determined according to the impedance distribution parameters, and the branch current change value is obtained by distributing the disturbance node current change value to each branch line included in the generator unit line based on the impedance distribution parameters;

[0133] A node inertia value determination module 33, configured to determine a node inertia value at the target node based on a node inertia distribution model of the generator unit line according to a second transmission line length value from the target node to each generator, where the node inertia distribution model is pre-constructed according to each generator inertia value and the first transmission line length value;

[0134] A node frequency change rate determination module 34, configured to determine a node frequency change rate at the target node according to the node disturbed power value and the node inertia value.

[0135] In a specific application scenario, the node disturbed power value calculation module is configured to:

[0136] Based on the impedance distribution parameters, distribute the disturbance node current change value to each branch line included in the generator unit line to obtain a branch current change value for each branch line;

[0137] Based on the impedance distribution parameters, obtain each impedance value included between the disturbance node and the target node, and determine the sum of each impedance value as the node impedance value at the target node;

[0138] Determine the product of the node impedance value and the branch current change value of the branch line where the target node is located as the disturbance power propagation voltage drop value at the target node;

[0139] Determine the difference between the disturbance node voltage change value and the disturbance power propagation voltage drop value as the node voltage change value at the target node;

[0140] Determine the product of the node voltage change value and the branch current change value as the node disturbed power value at the target node.

[0141] In a specific application scenario, the node disturbed power value calculation module is also used to:

[0142] Based on the impedance distribution parameter, calculating the branch impedance value of each branch line included in the generator set line, and calculating the proportion of each branch impedance value to the total impedance value of the generator set line;

[0143] Taking each of the branch routes as a target branch route one by one;

[0144] Determine the product of the sum of the proportions corresponding to other branch lines except the target branch line and the disturbance node current change value as the branch current change value of the target branch line;

[0145] The branch current change value of each branch line is obtained.

[0146] In a specific application scenario, before the node inertia value determination module, the device further includes a node inertia distribution model construction module, which is used to:

[0147] According to the generator inertia value of each generator and the length value of the first transmission line, a corresponding sub-node inertia distribution model is constructed based on a Gaussian distribution function;

[0148] The sub-node inertia distribution models of the generators in operation are added together to obtain the node inertia distribution model of the generator set line.

[0149] In a specific application scenario, the node frequency change rate determination module is used to:

[0150] The quotient of the node disturbed power value and the node inertia value of a preset multiple is determined as the node frequency change rate at the target node.

[0151] In a specific application scenario, the device further includes a frequency adjustment module, which is used to:

[0152] Selecting a plurality of points in the generator set circuit as preset nodes, and calculating the node frequency change rate at each of the preset nodes;

[0153] The system frequency of the generator set circuit is adjusted according to the frequency change rate of each node.

[0154] In a specific application scenario, the sub-node inertia distribution model is expressed as the following formula:

[0155]

[0156] Among them, H m,i (x i) represents the generator G m At node x i The node inertia at m,i Indicates the parameter, H m Indicates the generator G m The generator inertia value, c m,i Indicates the first transmission line length value.

[0157] The present application provides a device for determining a node frequency change rate. First, when a frequency disturbance is detected in a generator unit line, a disturbance node voltage change value and a disturbance node current change value at a disturbance node, an impedance distribution parameter of the generator unit line, a generator inertia value of each generator in the generator unit line, and a first transmission line length value between generators are obtained; secondly, according to a branch current change value and a node impedance value at a target node, and a disturbance node voltage change value, a node disturbed power value at the target node is calculated, wherein the node impedance value is determined according to the impedance distribution parameter, and the branch current change value and the node impedance value at the target node are determined according to the impedance distribution parameter. The line current change value is obtained by distributing the disturbance node current change value to each branch line included in the generator set line based on the impedance distribution parameter; thirdly, based on the node inertia distribution model of the generator set line, according to the second transmission line length value from the target node to each of the generators, the node inertia value at the target node is determined, and the node inertia distribution model is pre-constructed according to the inertia values ​​of each of the generators and the first transmission line length value; finally, according to the node disturbed power value and the node inertia value, the node frequency change rate at the target node is determined. Compared with the prior art, the embodiment of the present application distributes the disturbance node current change value to each branch line based on the impedance distribution parameter to obtain the branch current change value, and calculates the node disturbed power value of each node in combination with the disturbance node voltage change value. Since the loss of the disturbance power on the line and the difference in the impact of the disturbance on each node are fully considered, it is more suitable for the characteristics of the dual-high power system; further, the node inertia value is calculated using a pre-established node inertia distribution model. Since the model describes the distribution of the node inertia value in the line with the node position, the node inertia value of any node can be obtained according to the node position information, and then the node frequency change rate at any node can be obtained to meet the demand for system frequency regulation according to the node frequency change rate of any node, meet the system frequency regulation demand of the dual-high power system, and effectively improve the system frequency safety of the dual-high power system.

[0158] According to an embodiment of the present application, a storage medium is provided, wherein the storage medium stores at least one executable instruction, and the computer executable instruction can execute the interface access test method in any of the above method embodiments.

[0159] Based on this understanding, the technical solution of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.), and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each implementation scenario of the present application.

[0160] Figure 6 A schematic diagram of the structure of a terminal provided according to an embodiment of the present application is shown, and the specific embodiment of the present application does not limit the specific implementation of the terminal.

[0161] like Figure 6 As shown, the terminal may include: a processor (processor) 402 , a communication interface (Communications Interface) 404 , a memory (memory) 406 , and a communication bus 408 .

[0162] The processor 402 , the communication interface 404 , and the memory 406 communicate with each other via a communication bus 408 .

[0163] The communication interface 404 is used to communicate with other devices such as clients or other servers.

[0164] The processor 402 is used to execute the program 410, and specifically can execute the relevant steps in the above-mentioned node frequency change rate determination method embodiment.

[0165] Specifically, the program 410 may include program codes, which include computer operation instructions.

[0166] The processor 402 may be a central processing unit (CPU), or an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application. The one or more processors included in the computer device may be processors of the same type, such as one or more CPUs; or processors of different types, such as one or more CPUs and one or more ASICs.

[0167] The memory 406 is used to store the program 410. The memory 406 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0168] The program 410 may be specifically configured to enable the processor 402 to perform the following operations:

[0169] When a frequency disturbance is detected in the generator set line, a disturbance node voltage change value and a disturbance node current change value at the disturbance node, an impedance distribution parameter of the generator set line, a generator inertia value of each generator in the generator set line, and a first transmission line length value between the generators are obtained;

[0170] Calculating the node disturbed power value at the target node according to the branch current change value and the node impedance value at the target node and the disturbance node voltage change value, wherein the node impedance value is determined according to the impedance distribution parameter, and the branch current change value is obtained by distributing the disturbance node current change value to each branch line included in the generator unit line based on the impedance distribution parameter;

[0171] Based on the node inertia distribution model of the generator set line, the node inertia value at the target node is determined according to the second transmission line length value from the target node to each of the generators, wherein the node inertia distribution model is pre-constructed according to the inertia values ​​of each of the generators and the first transmission line length value;

[0172] The node frequency change rate at the target node is determined according to the node disturbed power value and the node inertia value.

[0173] The storage medium may also include an operating system and a network communication module. The operating system is a program that manages the hardware and software resources of the physical device of the method for determining the node frequency change rate, and supports the operation of the information processing program and other software and / or programs. The network communication module is used to realize the communication between the components inside the storage medium, and the communication with other hardware and software in the information processing physical device.

[0174] Each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system embodiment, since it basically corresponds to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0175] The method and system of the present application may be implemented in many ways. For example, the method and system of the present application may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above order of steps for the method is for illustration only, and the steps of the method of the present application are not limited to the order specifically described above, unless otherwise specifically stated. In addition, in some embodiments, the present application may also be implemented as a program recorded in a recording medium, which includes machine-readable instructions for implementing the method according to the present application. Therefore, the present application also covers a recording medium storing a program for executing the method according to the present application.

[0176] Obviously, those skilled in the art should understand that the above modules or steps of the present application can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, and optionally, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order from that herein, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present application is not limited to any specific combination of hardware and software.

[0177] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for determining a node frequency change rate, characterized in that: include: When a frequency disturbance is detected in the generator set line, a disturbance node voltage change value and a disturbance node current change value at the disturbance node, an impedance distribution parameter of the generator set line, a generator inertia value of each generator in the generator set line, and a first transmission line length value between the generators are obtained; Calculating the node disturbed power value at the target node according to the branch current change value and the node impedance value at the target node and the disturbance node voltage change value, wherein the node impedance value is determined according to the impedance distribution parameter, and the branch current change value is obtained by distributing the disturbance node current change value to each branch line included in the generator unit line based on the impedance distribution parameter; Based on the node inertia distribution model of the generator set line, the node inertia value at the target node is determined according to the second transmission line length value from the target node to each of the generators, wherein the node inertia distribution model is pre-constructed according to the inertia values ​​of each of the generators and the first transmission line length value; The node frequency change rate at the target node is determined according to the node disturbed power value and the node inertia value.

2. The method according to claim 1, characterized in that The step of calculating the node disturbed power value at the target node according to the branch current change value and the node impedance value at the target node and the disturbance node voltage change value comprises: Based on the impedance distribution parameter, the disturbance node current change value is distributed to each branch line included in the generator unit line to obtain the branch current change value of each branch line; Based on the impedance distribution parameter, each impedance value between the disturbance node and the target node is obtained, and the sum of each impedance value is determined as the node impedance value at the target node; Determine the product of the node impedance value and the branch current change value of the branch line where the target node is located as the disturbance power propagation voltage drop value at the target node; Determine the difference between the disturbance node voltage change value and the disturbance power propagation voltage drop value as the node voltage change value at the target node; The product of the node voltage change value and the branch current change value is determined as the node disturbed power value at the target node.

3. The method according to claim 2, characterized in that The step of distributing the disturbance node current change value to each branch line included in the generator set line based on the impedance distribution parameter to obtain the branch current change value of each branch line includes: Based on the impedance distribution parameter, calculating the branch impedance value of each branch line included in the generator set line, and calculating the proportion of each branch impedance value to the total impedance value of the generator set line; Taking each of the branch routes as a target branch route one by one; Determine the product of the sum of the proportions corresponding to other branch lines except the target branch line and the disturbance node current change value as the branch current change value of the target branch line; The branch current change value of each branch line is obtained.

4. The method according to claim 1, characterized in that: Before determining the node inertia value at the target node based on the node inertia distribution model of the generator set line according to the second transmission line length value from the target node to each of the generators, the method further includes: According to the generator inertia value of each generator and the length value of the first transmission line, a corresponding sub-node inertia distribution model is constructed based on a Gaussian distribution function; The sub-node inertia distribution models of the generators in operation are added together to obtain the node inertia distribution model of the generator set line.

5. The method according to claim 1, characterized in that The determining the node frequency change rate at the target node according to the node disturbed power value and the node inertia value includes: The quotient of the node disturbed power value and the node inertia value of a preset multiple is determined as the node frequency change rate at the target node.

6. The method according to claim 1, characterized in that The method further comprises: Selecting a plurality of points in the generator set circuit as preset nodes, and calculating the node frequency change rate at each of the preset nodes; The system frequency of the generator set circuit is adjusted according to the frequency change rate of each node.

7. The method according to claim 4, characterized in that The sub-node inertia distribution model is expressed as the following formula: Among them, H m,i (x i ) represents the generator G m At node x i The node inertia at m,i Indicates the parameter, H m Represents the generator G m The generator inertia value, c m,i Indicates the first transmission line length value.

8. A device for determining a node frequency change rate, characterized in that: include: A data acquisition module is used to acquire a disturbance node voltage change value and a disturbance node current change value at a disturbance node, an impedance distribution parameter of the generator unit line, a generator inertia value of each generator in the generator unit line, and a first transmission line length value between generators when a frequency disturbance is detected in the generator unit line; A node disturbed power value calculation module, used to calculate the node disturbed power value at the target node according to the branch current change value and the node impedance value at the target node and the disturbance node voltage change value, wherein the node impedance value is determined according to the impedance distribution parameter, and the branch current change value is obtained by distributing the disturbance node current change value to each branch line included in the generator unit line based on the impedance distribution parameter; a node inertia value determination module, configured to determine the node inertia value at the target node based on a node inertia distribution model of the generator set line and according to a second transmission line length value from the target node to each of the generators, wherein the node inertia distribution model is pre-constructed according to the inertia values ​​of each of the generators and the first transmission line length value; The node frequency change rate determination module is used to determine the node frequency change rate at the target node according to the node disturbed power value and the node inertia value.

9. A storage medium, wherein at least one executable instruction is stored in the storage medium, characterized in that: The executable instructions enable the processor to execute operations corresponding to the method for determining the node frequency change rate according to any one of claims 1 to 7.

10. A terminal, comprising: A processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, wherein the executable instruction enables the processor to perform an operation corresponding to the method for determining the node frequency change rate according to any one of claims 1-7.

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