External characteristic aggregation equivalent interaction method, device, and medium for new energy collection area

Abstract

The present invention discloses an external characteristic aggregation equivalent interaction method, device, and medium for a new energy collection area, belonging to the technical field of new energy external characteristic equivalent interaction. By searching for boundary substations and adjacent substations and performing marking processing according to whether they contain new energy components, a more accurate mathematical model of the power grid can be constructed, which helps to accurately reflect the existence and influence of new energy power stations when calculating the equivalent value at the provincial and local interface; by setting a transition resistance and performing iterative calculations, the change of new energy fault current can be simulated, thereby fully considering the influence of new energy short-circuit current on the equivalent model and relay protection setting values, making the equivalent model closer to the actual power grid operation conditions; by fully considering the influence of new energy short-circuit current, improving the equivalent interaction mode, and enhancing the accuracy of the equivalent model and the adaptability of relay protection setting values, it provides a strong guarantee for the safe and stable operation of the power grid system.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy external characteristic equivalent interaction, and particularly relates to an external characteristic aggregation equivalent interaction method for a new energy collection area. Background Art

[0002] Multi-level control institutions rely on a unified data model, graphic model, setting calculation basic platform, and setting calculation principles to achieve the interconnection and efficient collaboration of power grid relay protection setting calculations. Under the current technical architecture, both the provincial control center (provincial dispatching) and the regional control center (regional dispatching) adopt an integrated setting calculation system, which adopts a distributed deployment strategy. Specifically, the provincial dispatching and the regional dispatching are respectively equipped with independent servers and are each responsible for maintaining relevant setting calculation basic data. In terms of the interaction of the power grid model, data is exchanged at the interface in an equivalent form between the provincial and regional dispatching. Among them, the provincial dispatching issues the equivalent model of the deployed area to the regional dispatching, and the regional dispatching reports the corresponding equivalent model to the provincial dispatching. This mechanism ensures that when the provincial dispatching and the regional dispatching perform setting calculations, they can operate based on a unified and complete power grid model, thereby effectively ensuring the accuracy of short-circuit current and branch coefficient calculations, as well as the correctness of relay protection settings.

[0003] However, with the continuous increase in the penetration rate of new energy in the regional dispatching power grid, the behavioral characteristics of the power grid during a fault have changed significantly. New energy power stations, relying on their low-voltage ride-through characteristics, inject short-circuit current into the power grid during a power grid fault. This injection behavior has a non-negligible impact on the sensitivity and selectivity of relay protection settings, which may lead to protection refusal or misoperation. Currently, the equivalent model at the provincial and regional dispatching interface has not fully considered this impact of new energy, which to a certain extent weakens the accuracy and reliability of the relay protection settings of the provincial dispatching.

[0004] In view of the increasingly significant impact of new energy short-circuit current on the equivalent model at the provincial and regional dispatching interface and relay protection settings, the constant impedance equivalent interaction mode in the existing technology can no longer meet the setting calculation requirements under the new power system. Therefore, how to fully consider the impact of new energy short-circuit current when calculating the equivalent at the provincial and regional dispatching interface, so as to improve the existing equivalent interaction mode, has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide an external characteristic aggregation equivalent interaction method, device, and medium for a new energy collection area, aiming to overcome the problem in the existing technology that the accuracy and reliability of relay protection settings are weakened due to the failure to fully incorporate new energy factors into the equivalent interaction model.

[0006] The present invention solves the above technical problems through the following technical solutions:

[0007] An external characteristic aggregation equivalent interaction method for a new energy collection area, comprising the following steps:

[0008] S1. Based on the voltage level of the local dispatching power grid, find all boundary substations;

[0009] S2. Starting from the boundary substation, along the voltage level of the local dispatching power grid, find adjacent substations;

[0010] S3. Based on whether the substation contains new energy components, label the busbars of the substations. If the substation contains new energy components, label the busbar of the substation as a new energy busbar; if the substation does not contain new energy components, label the busbar of the substation as a conventional power source busbar. The substations include boundary substations and adjacent substations; based on the results of the labeling process, generate a mathematical model;

[0011] S4. When the busbar to be calculated is a conventional power source busbar, according to the generated mathematical model, calculate the equivalent model of each fault node of the conventional power source busbar in turn and report it to the provincial dispatching; when the busbar to be calculated is a new energy busbar, according to the generated mathematical model, by setting a transition resistance, change the new energy fault current injected into the new energy busbar, and iteratively calculate the external characteristic equivalent model of each fault node of the new energy busbar and report it to the provincial dispatching;

[0012] S5. Through the provincial dispatching, aggregate the equivalent model of the conventional power source busbar and the external characteristic equivalent model of the new energy busbar to obtain an external characteristic aggregation equivalent model. The provincial dispatching performs interactive control on the new energy collection area based on the external characteristic aggregation equivalent model.

[0013] A further improvement of the present invention is that the new energy components are photovoltaic elements or wind turbine elements.

[0014] A further improvement of the present invention is that S3 specifically includes the following steps: traverse all substations, label the busbars of the substations. If the substation contains new energy components, label the busbar of the substation as a new energy busbar; if the substation does not contain new energy components, label the busbar of the substation as a conventional power source busbar. Record the conventional power source busbars and new energy busbars in the conventional power source busbar set A and the new energy busbar set B respectively. Among them, the conventional power source busbar set A contains N conventional power source busbars, and the new energy busbar set B contains M new energy busbars; based on the results of the labeling process, combined with the topological connection relationship between the boundary substations, adjacent substations and the local dispatching power grid, as well as the impedance information and operating status of the local dispatching equipment, generate a mathematical model.

[0015] A further improvement of the present invention is that when the bus to be calculated is a conventional power supply bus, the following steps are further included: set r = 0, where r represents the position of the current conventional power supply bus in the set A of conventional power supply buses; when the bus to be calculated is a new energy bus, the following steps are further included: set s = 0, where s represents the position of the current new energy bus in the set B of new energy buses.

[0016] A further improvement of the present invention is that calculating the equivalent model of each conventional power supply bus fault node in sequence specifically includes the following steps: let r = r + 1, make the current conventional power supply bus operate in the maximum operating mode, and based on the mathematical model of S3, calculate the first equivalent information of the fault node f of the current conventional power supply bus, including the positive sequence impedance Z f1max and the zero sequence impedance Z f0max ; make the current conventional power supply bus operate in the minimum operating mode, and based on the mathematical model of S3, calculate the second equivalent information of the fault node f of the current conventional power supply bus, including the positive sequence impedance Z f1min and the zero sequence impedance Z f0min ; determine whether r is equal to N. If the determination is no, then execute S5 again; if the determination is yes, then report all the calculated first equivalent information and second equivalent information as the equivalent model of the conventional power supply bus to the provincial dispatching center;

[0017] Among them, the maximum operating mode refers to an operating mode in which when the current conventional power supply bus operates in this operating mode, it has the smallest short-circuit impedance value and the largest short-circuit current generated after a short circuit occurs; the minimum operating mode refers to an operating mode in which when the current conventional power supply bus operates in this operating mode, it has the largest short-circuit impedance and the smallest short-circuit current generated after a short circuit occurs.

[0018] A further improvement of the present invention is that iteratively calculating the external characteristic equivalent model of each new energy bus fault node specifically includes the following steps:

[0019] S41. Let s = s + 1, i = 1, initialize the transition resistance , set the upper limit of the transition resistance to R lim , set the increment of the transition resistance to , where i represents the number of iterations of the transition resistance; set k = 0, where k represents the number of times of injecting new energy fault current into the current new energy bus;

[0020] S42. Let k = k + 1, obtain the terminal voltage, inject the kth new energy fault current into the current new energy bus, and based on the terminal voltage, calculate the first current parameters of all new energy nodes p associated with the plant corresponding to the current new energy bus in the mathematical model, including the positive sequence current and the negative sequence current ;

[0021] S43. Obtain the positive-sequence impedance, negative-sequence impedance, and zero-sequence impedance of the conventional power source equivalent of the current new energy busbar, where the positive-sequence impedance and negative-sequence impedance are both Z f1 , and the zero-sequence impedance is Z f0 . Calculate the second current parameters of the fault node f of the current new energy busbar according to the first current parameters, including the positive-sequence current and the negative-sequence current ;

[0022] S44. Based on the first current parameters and the second current parameters, calculate the first voltage parameters of all new energy nodes p associated with the plant station corresponding to the current new energy busbar in the mathematical model, including the positive-sequence voltage , the negative-sequence voltage and the zero-sequence voltage ; Determine whether the difference between the current first voltage parameters and the previous first voltage parameters meets the convergence accuracy. When k = 1, the terminal voltage is the previous first voltage parameters. If the difference meets the convergence accuracy, execute S45; if the difference does not meet the convergence accuracy, return to S42;

[0023] S45. Let i = i + 1, the current transition resistance , is the previous transition resistance, and judge whether it is greater than or equal to the transition resistance upper limit R lim . If the judgment is no, then return to S42; if the judgment is yes, then enter S46;

[0024] S46. Obtain the second current parameters of the current fault node f, and calculate the second voltage parameters of the current fault node f according to the second current parameters, including the positive-sequence voltage , the negative-sequence voltage . Based on the second current parameters and the second voltage parameters, generate the fault amplitude curve and the phase angle curve; judge whether s is equal to M. If the judgment is no, then return to S41; if the judgment is yes, then report all the fault amplitude curves and phase angle curves as the external characteristic equivalent model of the new energy busbar to the provincial dispatching center.

[0025] A further improvement of the present invention is that the first current parameter is specifically:

[0026]

[0027] where j is the imaginary part symbol in the complex number; , , are respectively the steady-state positive-sequence short-circuit current, active component, and reactive component corresponding to the new energy node p in the k-th cycle under the i-th transition resistance; , , They are respectively the steady-state negative-sequence short-circuit current amplitude, active component, and reactive component of the substation corresponding to the new energy node p after the new energy busbar fault; the superscript i represents the iteration number of the i-th transition resistance; the superscript k represents the number of times of injecting new energy fault current into the current new energy busbar; the subscript d represents the active component of the current; the subscript q represents the reactive component of the current; the subscript 1 represents the positive-sequence current; the subscript 2 represents the negative-sequence current; To reflect the new energy current controlled by its terminal voltage and the positive-sequence voltage Function; To reflect the new energy current controlled by its terminal voltage and the negative-sequence voltage Function;

[0028] The second current parameter is specifically:

[0029] If the fault is a single-phase ground fault, then:

[0030]

[0031] Among them, Is the positive-sequence short-circuit current of the fault node in the k-th cycle of the new energy under the i-th transition resistance, Is the negative-sequence short-circuit current of the fault node in the k-th cycle of the new energy under the i-th transition resistance, Is the positive-sequence impedance of the fault node f, Is the zero-sequence impedance of the fault node f, Is the grounding resistance of the single-phase short-circuit fault in the i-th cycle, Is the positive-sequence mutual impedance between the fault node f and the new energy node p;

[0032] If the fault is a two-phase interphase fault, then:

[0033]

[0034] If the fault is a two-phase ground fault, then:

[0035]

[0036]

[0037] Among them, / / represents the union operation;

[0038] If the fault is a three-phase interphase fault, the positive-sequence current and negative-sequence current of the fault node are:

[0039]

[0040] 。

[0041] A further improvement of the present invention lies in: The first voltage parameter is specifically:

[0042]

[0043]

[0044]

[0045] Among them, is the positive-sequence voltage of the new energy node p in the k-th cycle of the new energy under the i-th transition resistance, is the negative-sequence voltage of the new energy node p in the k-th cycle of the new energy under the i-th transition resistance, is the zero-sequence voltage of the new energy node p in the k-th cycle of the new energy under the i-th transition resistance, and are the positive-sequence and negative-sequence self-impedances of the new energy node p respectively, is the negative-sequence short-circuit current provided by the new energy node p for the k-th time in the i-th cycle, is the zero-sequence short-circuit current provided by the fault node f in the k-th cycle of the new energy under the i-th transition resistance, is the negative-sequence mutual impedance between the fault node f and the new energy node p, is the zero-sequence mutual impedance between the fault node f and the new energy node p;

[0046] The second voltage parameter is specifically:

[0047]

[0048]

[0049] Among them, and are the positive-sequence and negative-sequence self-impedances of the fault node respectively.

[0050] A terminal device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the above method are implemented.

[0051] A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the steps of the above method are implemented.

[0052] Compared with the prior art, the positive and progressive effects of the present invention are as follows:

[0053] The external characteristic aggregation equivalent interaction method for new energy collection areas provided by the present invention can more accurately construct the mathematical model of the power grid by searching for boundary substations and adjacent substations and performing tagging processing according to whether they contain new energy components, which helps to accurately reflect the existence and influence of new energy power stations when calculating the equivalent value at the provincial and local interface; by setting the transition resistance and iterative calculation, it can simulate the change of new energy fault current, thus fully considering the influence of new energy short-circuit current on the equivalent model and relay protection setting values, making the equivalent model closer to the actual power grid operation conditions; by fully considering the influence of new energy short-circuit current, it improves the equivalent interaction mode, enhances the accuracy of the equivalent model and the adaptability of relay protection setting values, and provides a strong guarantee for the safe and stable operation of the power grid system. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The accompanying drawings in the specification are used to provide a further understanding of the present invention, and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0055] Figure 1 It is a flowchart of the method of the present invention;

[0056] Figure 2 It is a flowchart of the conventional power supply bus;

[0057] Figure 3 It is a flowchart of the new energy bus. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0058] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and shown in the accompanying drawings here can be arranged and designed in various different configurations.

[0059] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents the selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0060] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0061] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invention product is usually placed during use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation on the present invention. In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0062] In addition, it should also be noted that unless otherwise clearly specified and defined, if terms such as "set", "install", "connect", "couple" are understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0063] The following further elaborates on the present invention in detail in conjunction with the drawings and specific embodiments, which is an explanation rather than a limitation of the present invention.

[0064] See Figure 1 , the present invention provides an external characteristic aggregation equivalent interaction method for a new energy collection area, including the following steps:

[0065] S1. Based on the voltage level to which the local dispatching power grid belongs, find all boundary substations;

[0066] S2. Starting from the boundary substation, along the voltage level to which the local dispatching power grid belongs, find adjacent substations;

[0067] S3. Based on whether the substation contains new energy components, perform marking processing on the busbars of the substations. If the substation contains new energy components, mark the busbar of the substation as a new energy busbar; if the substation does not contain new energy components, mark the busbar of the substation as a conventional power source busbar. The substations include boundary substations and adjacent substations; based on the results of the marking processing, generate a mathematical model;

[0068] S4. When the busbar to be calculated is a conventional power source busbar, according to the generated mathematical model, calculate the equivalent model of each fault node of the conventional power source busbar in turn and report it to the provincial dispatching; when the busbar to be calculated is a new energy busbar, according to the generated mathematical model, by setting a transition resistance, change the new energy fault current injected into the new energy busbar, and iteratively calculate the external characteristic equivalent model of each fault node of the new energy busbar and report it to the provincial dispatching;

[0069] S5. By aggregating the equivalent model of the conventional power generation busbars and the external characteristic equivalent model of the new energy busbars at the provincial dispatching center, an external characteristic aggregated equivalent model is obtained. Based on this model, the provincial dispatching center conducts interactive control on the new energy collection area.

[0070] By searching for boundary substations and adjacent substations and marking them according to whether they contain new energy components, a more accurate mathematical model of the power grid can be constructed, which helps to accurately reflect the existence and influence of new energy power stations when calculating the equivalent value at the provincial-local interface. By setting the transition resistance and performing iterative calculations, the change of the new energy fault current can be simulated, so as to fully consider the influence of the new energy short-circuit current on the equivalent model and the relay protection setting values, making the equivalent model closer to the actual operation of the power grid. By fully considering the influence of the new energy short-circuit current, the equivalent interaction mode is improved, the accuracy of the equivalent model and the adaptability of the relay protection setting values are enhanced, providing a strong guarantee for the safe and stable operation of the power grid system.

[0071] In a specific embodiment of the present invention, S2. Starting from the boundary substations, search for adjacent substations along the voltage levels belonging to the local dispatching power grid, which specifically includes the following steps: Taking each boundary substation as the starting point, along the voltage levels belonging to the local dispatching, based on the breadth of the electrical distance characteristics, search for all adjacent substations L1 within the first-level range of the boundary substations. Taking the adjacent substations L1 as the starting point, expand outward along the voltage levels belonging to the local dispatching to search for the adjacent substations L2 corresponding to the adjacent substations L1. The adjacent substations L2 are the substations within the first-level to second-level range of the boundary substations. Taking the adjacent substations L2 as the starting point, expand outward along the voltage levels belonging to the local dispatching to search for the adjacent substations L3 corresponding to the adjacent substations L2. The level range of the boundary substations can be considered set, generally defaulting to 3 levels.

[0072] Since the boundary substations contain both the equipment of the provincial dispatching center and the local dispatching center, during the setting calculation, the provincial dispatching center only draws the model of the provincial dispatching center, and the model of the local dispatching center is replaced by an equivalent value; the local dispatching center only draws the model of the local dispatching center, and the model of the provincial dispatching center is replaced by an equivalent value, so these substations are called boundary substations; Adjacent substations: Because a line has two sides, one side is at substation R and the other side is at substation T, then substation T is the adjacent substation of substation R. The boundary substation can also be understood as the root node of a tree, the line between the two stations is understood as a branch, and the adjacent substations are the tree child nodes connected to the tree node. These adjacent substations are the first-level nodes, and then taking the first-level nodes as the starting point, search for the stations connected to them, and the stations found are the second-level nodes, and so on.

[0073] Specifically, the new energy component is a photovoltaic element or a wind turbine element.

[0074] Specifically, S3 specifically includes the following steps: Traverse all substations, label the buses of the substations. If a substation contains new energy components, label the bus of this substation as a new energy bus; if a substation does not contain new energy components, label the bus of this substation as a conventional power supply bus, and record the conventional power supply buses and new energy buses in the conventional power supply bus set A and the new energy bus set B respectively. Among them, the conventional power supply bus set A contains N conventional power supply buses, and the new energy bus set B contains M new energy buses; Based on the results of the labeling process, combined with the topological connection relationship between the boundary substations, adjacent substations and the dispatching center power grid, as well as the impedance information and operating status of the dispatching center equipment, generate a mathematical model.

[0075] Specifically, when the bus to be calculated is a conventional power supply bus, the following steps are further included: Set r = 0, where r represents the position of the current conventional power supply bus in the conventional power supply bus set A; when the bus to be calculated is a new energy bus, the following steps are further included: Set s = 0, where s represents the position of the current new energy bus in the new energy bus set B.

[0076] Specifically, refer to Figure 2 and calculate the equivalent model of each conventional power supply bus fault node in sequence, which specifically includes the following steps: Let r = r + 1, make the current conventional power supply bus operate in the maximum operating mode, and based on the mathematical model of S3, calculate the first equivalent information of the fault node f of the current conventional power supply bus, including the positive sequence impedance Z f1max and the zero sequence impedance Z f0max ; Make the current conventional power supply bus operate in the minimum operating mode, and based on the mathematical model of S3, calculate the second equivalent information of the fault node f of the current conventional power supply bus, including the positive sequence impedance Z f1min and the zero sequence impedance Z f0min ; Judge whether r is equal to N. If the judgment is no, then execute S5 again; if the judgment is yes, report all the calculated first equivalent information and second equivalent information as the equivalent model of the conventional power supply bus to the provincial dispatching center;

[0077] Among them, the maximum operating mode refers to a operating mode in which when the current conventional power supply bus operates in this mode, it has the minimum short - circuit impedance value and the maximum short - circuit current is generated after a short - circuit occurs; the minimum operating mode refers to a operating mode in which when the current conventional power supply bus operates in this mode, it has the maximum short - circuit impedance and the minimum short - circuit current is generated after a short - circuit occurs.

[0078] Specifically, refer to Figure 3 and iteratively calculate the external characteristic equivalent model of each new energy bus fault node, which specifically includes the following steps:

[0079] S41. Let s = s + 1, i = 1, initialize the transition resistance and set the upper limit of the transition resistance to Rlim , set the transition resistance increment to , where i represents the iteration number of the transition resistance; set k = 0, and k represents the number of times of injecting new energy fault current into the current new energy bus;

[0080] S42. Let k = k + 1, obtain the terminal voltage, inject the kth new energy fault current into the current new energy bus, and based on the terminal voltage, calculate the first current parameters of all new energy nodes p associated with the plant corresponding to the current new energy bus in the mathematical model, including positive sequence current and negative sequence current ;

[0081] S43. Obtain the positive sequence impedance, negative sequence impedance and zero sequence impedance of the conventional power source equivalent of the current new energy bus, where the positive sequence impedance and negative sequence impedance are both Z f1 , and the zero sequence impedance is Z f0 , and based on the first current parameters, calculate the second current parameters of the fault node f of the current new energy bus, including positive sequence current and negative sequence current ;

[0082] S44. Based on the first current parameters and the second current parameters, calculate the first voltage parameters of all new energy nodes p associated with the plant corresponding to the current new energy bus in the mathematical model, including positive sequence voltage , negative sequence voltage and zero sequence voltage ; judge whether the difference between the current first voltage parameters and the previous first voltage parameters meets the convergence accuracy. When k = 1, the terminal voltage is the previous first voltage parameters. If the difference meets the convergence accuracy, execute S45; if the difference does not meet the convergence accuracy, return to S42;

[0083] S45. Let i = i + 1, the current transition resistance , is the previous transition resistance, judge whether is greater than or equal to the transition resistance upper limit R lim . If the judgment is no, then return to S42; if the judgment is yes, then enter S46;

[0084] S46. Obtain the second current parameters of the current fault node f, and calculate the second voltage parameters of the current fault node f according to the second current parameters, including positive sequence voltage , negative sequence voltage . Based on the second current parameters and the second voltage parameters, generate the fault amplitude curve and phase angle curve; judge whether s is equal to M. If the judgment is no, then return to S41; if the judgment is yes, then report all the fault amplitude curves and phase angle curves as the external characteristic equivalent model of the new energy bus to the provincial dispatching center.

[0085] Specifically, the first current parameter is specifically:

[0086]

[0087] where j is the imaginary part symbol in complex numbers; , , are respectively the steady-state positive-sequence short-circuit current, active component, and reactive component corresponding to the new energy node p in the k-th cycle under the i-th transition resistance; , , are respectively the magnitude, active component, and reactive component of the steady-state negative-sequence short-circuit current of the substation corresponding to the new energy node p after the new energy busbar fails; the superscript i represents the iteration number of the i-th transition resistance; the superscript k represents the number of times of injecting new energy fault current into the current new energy busbar; the subscript d represents the active component of the current; the subscript q represents the reactive component of the current; the subscript 1 represents the positive-sequence current; the subscript 2 represents the negative-sequence current; is a function reflecting the new energy current controlled by its terminal voltage and the positive-sequence voltage ; is a function reflecting the new energy current controlled by its terminal voltage and the negative-sequence voltage ;

[0088] The second current parameter is specifically:

[0089] If the fault is a single-phase grounding fault, then:

[0090]

[0091] where is the positive-sequence short-circuit current of the fault node in the k-th cycle of the new energy under the i-th transition resistance, is the negative-sequence short-circuit current of the fault node in the k-th cycle of the new energy under the i-th transition resistance, is the positive-sequence impedance of the fault node f, is the zero-sequence impedance of the fault node f, is the grounding resistance of the single-phase short-circuit fault in the i-th cycle, is the positive-sequence mutual impedance between the fault node f and the new energy node p;

[0092] If the fault is a two-phase interphase fault, then:

[0093]

[0094] If the fault is a two-phase grounding fault, then:

[0095]

[0096]

[0097] Among them, / / represents the union operation;

[0098] If the fault is a three-phase interphase fault, the positive-sequence current and negative-sequence current of the fault node are:

[0099]

[0100] .

[0101] Specifically, the first voltage parameter is specifically:

[0102]

[0103]

[0104]

[0105] Among them, is the positive-sequence voltage of the new energy node p in the k-th cycle of the new energy under the i-th transition resistance, is the negative-sequence voltage of the new energy node p in the k-th cycle of the new energy under the i-th transition resistance, is the zero-sequence voltage of the new energy node p in the k-th cycle of the new energy under the i-th transition resistance, , are the positive-sequence and negative-sequence self-impedances of the new energy node p respectively, is the negative-sequence short-circuit current provided by the new energy node p for the k-th time in the i-th cycle, is the zero-sequence short-circuit current provided by the fault node f in the k-th cycle of the new energy under the i-th transition resistance, is the negative-sequence mutual impedance between the fault node f and the new energy node p, is the zero-sequence mutual impedance between the fault node f and the new energy node p;

[0106] The second voltage parameter is specifically:

[0107]

[0108]

[0109] Among them, , are the positive-sequence and negative-sequence self-impedances of the fault node respectively.

[0110] Based on the same inventive concept, an embodiment of the present application provides a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the external characteristic aggregation equivalent interaction method for the new energy collection area. Among them, the memory may include internal memory, such as high-speed random access memory, and may also include non-volatile memory, such as at least one disk memory, etc.; the processor, network interface, and memory are interconnected through an internal bus, and this internal bus can be an Industry Standard Architecture bus, a Peripheral Component Interconnect standard bus, an Extended Industry Standard Architecture bus, etc., and the bus can be divided into an address bus, a data bus, a control bus, etc. The memory is used to store programs. Specifically, the program may include program code, and the program code includes computer operation instructions. The memory may include internal memory and non-volatile memory, and provide instructions and data to the processor.

[0111] Based on the same inventive concept, an embodiment of the present application provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the steps of the external characteristic aggregation equivalent interaction method for the new energy collection area. Specifically, the computer-readable storage medium includes, but is not limited to, for example, volatile memory and / or non-volatile memory. The volatile memory may include RAM (Random Access Memory) and / or cache memory, etc. The non-volatile memory may include ROM (Read-Only Memory), hard disk, flash memory, optical disc, magnetic disk, etc.

[0112] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely 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 memory, CD-ROM (Compact Disc Read-Only Memory), optical memory, etc.) containing computer-usable program code.

[0113] The present invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each flow and / or block in the flowchart illustrations and / or block diagrams, and combinations of flows and / or blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions executed by the processor of the computer apparatus or other programmable data processing apparatus create means for implementing the functions specified in the flowchart flow or flows and / or block or blocks. Figure 1 in a flow or flows and / or block or blocks Figure 1 or blocks.

[0114] These computer program instructions may also be stored in a computer-readable memory that can direct a computer apparatus or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means that implement the functions specified in the flowchart flow or flows and / or block or blocks. Figure 1 in a flow or flows and / or block or blocks Figure 1 or blocks.

[0115] These computer program instructions may also be loaded onto a computer apparatus or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer apparatus or other programmable apparatus to produce a computer-implemented process, such that the instructions executed on the computer apparatus or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and / or block or blocks. Figure 1 in a flow or flows and / or block or blocks Figure 1 or blocks.

[0116] Although the preferred embodiments of the present invention have been described, additional changes and modifications can be made by those skilled in the art once they learn of the basic inventive concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0117] It is apparent that those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the 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 modifications and variations.

Claims

1. A method for external characteristic aggregation and equivalent interaction of a new energy gathering area, characterized in that: The following steps are involved: S1. Find all boundary plants and stations based on the voltage level of the local power grid; S2, starting from the boundary power plant, searching for adjacent power plants along the voltage level of the local power grid; S3. Based on whether the plant station contains new energy components, the busbar of the plant station is marked. If the plant station contains new energy components, the busbar of the plant station is marked as a new energy busbar; if the plant station does not contain new energy components, the busbar of the plant station is marked as a conventional power busbar, and the plant station includes a boundary plant station and an adjacent plant station; based on the result of the marking process, a mathematical model is generated; S4. When the bus to be calculated is a conventional power bus, according to the generated mathematical model, the equivalent model of each conventional power bus fault node is calculated in turn, and reported to the provincial dispatching; when the bus to be calculated is a new energy bus, according to the generated mathematical model, by setting the transition resistance, the new energy fault current injected into the new energy bus is changed, and the external characteristic equivalent model of each new energy bus fault node is iteratively calculated, and reported to the provincial dispatching; S5. The provincial dispatching department aggregates the equivalent model of the conventional power bus and the external characteristic equivalent model of the new energy bus to obtain an external characteristic aggregate equivalent model. The provincial dispatching department interactively controls the new energy collection area based on the external characteristic aggregate equivalent model. S3 specifically includes the following steps: traverse all power plants and stations, mark the bus of the power plants and stations, if the power plants and stations contain new energy components, mark the bus of the power plants and stations as new energy bus; if the power plants and stations do not contain new energy components, mark the bus of the power plants and stations as conventional power bus, and record the conventional power bus and the new energy bus in conventional power bus set A and new energy bus set B respectively, wherein the conventional power bus set A contains N conventional power buses, and the new energy bus set B contains M new energy buses; based on the result of the marking process, combined with the topological connection relationship between the boundary power plants and stations, the adjacent power plants and stations and the ground-adjusting power grid, as well as the impedance information and operating status of the ground-adjusting equipment, generate a mathematical model; When the bus to be calculated is a conventional power bus, the following steps are also included: setting r=0, where r represents the rank of the current conventional power bus in the conventional power bus set A; when the bus to be calculated is a new energy bus, the following steps are also included: setting s=0, where s represents the rank of the current new energy bus in the new energy bus set B; The equivalent model of each conventional power bus fault node is calculated in turn, which specifically includes the following steps: let r = r + 1, so that the current conventional power bus operates in the maximum operation mode, and based on the mathematical model of S3, calculate the first equivalent information of the current conventional power bus fault node f, including the positive sequence impedance Z f1max and zero sequence impedance Z f0max ; Make the current conventional power bus in the minimum operating mode, based on the mathematical model of S3, calculate the second equivalent information of the current conventional power bus fault node f, including the positive sequence impedance Z f1min and zero sequence impedance Z f0min ; Determine whether r is equal to N. If it is not, execute S5 again; if it is yes, report all the calculated first equivalent information and second equivalent information as the equivalent model of the conventional power bus to the provincial dispatching department; Among them, the maximum operation mode refers to an operation mode in which the current conventional power bus has the smallest short-circuit impedance value when it is running under this operation mode, and the short-circuit current generated after a short circuit occurs is the largest; the minimum operation mode refers to an operation mode in which the current conventional power bus has the largest short-circuit impedance when it is running under this operation mode, and the short-circuit current generated after a short circuit occurs is the smallest; The iterative calculation of the external characteristic equivalent model of each new energy bus fault node specifically includes the following steps: S41, let s=s+1, i=1, initialize the transition resistance , set the upper limit of transition resistance to R lim , set the transition resistance increment to , where i represents the number of iterations of the transition resistance; k is set to 0, k represents the number of times the new energy fault current is injected into the current new energy bus; S42, let k = k + 1, obtain the terminal voltage, inject the kth new energy fault current into the current new energy bus, and calculate the first current parameters of all new energy nodes p associated with the plant corresponding to the current new energy bus in the mathematical model based on the terminal voltage, including the positive sequence current and negative sequence current ; S43, obtain the positive sequence impedance, negative sequence impedance and zero sequence impedance of the conventional power supply equivalent of the current new energy bus, where the positive sequence impedance and negative sequence impedance are both Z f1 , zero sequence impedance is Z f0 , combined with the first current parameter, calculate the second current parameter of the current new energy bus fault node f, including the positive sequence current and negative sequence current ; S44, based on the first current parameter and the second current parameter, calculate the first voltage parameters of all new energy nodes p associated with the plant corresponding to the current new energy bus in the mathematical model, including the positive sequence voltage , negative sequence voltage and zero sequence voltage ; Determine whether the difference between the current first voltage parameter and the last first voltage parameter meets the convergence accuracy. When k=1, the terminal voltage is the last first voltage parameter. If the difference meets the convergence accuracy, execute S45; if the difference does not meet the convergence accuracy, return to S42; S45, let i=i+1, current transition resistance , is the last transition resistance, judge Is it greater than or equal to the upper limit of transition resistance R lim If the judgment is no, then return to S42; if the judgment is yes, then enter S46; S46, obtaining the second current parameter of the current fault node f, and calculating the second voltage parameter of the current fault node f according to the second current parameter, including the positive sequence voltage , negative sequence voltage , based on the second current parameter and the second voltage parameter, generate a fault amplitude curve and a phase angle curve; determine whether s is equal to M, if not, return to S41; if yes, report all fault amplitude curves and phase angle curves to the provincial dispatching department as the external characteristic equivalent model of the new energy bus.

2. According to claim 1, a method for external characteristic aggregation equivalent interaction of a new energy gathering area is characterized in that: The new energy component is a photovoltaic element or a wind turbine element.

3. According to claim 1, a method for external characteristic aggregation equivalent interaction of a new energy gathering area is characterized in that: The first current parameter is specifically: Where j is the symbol of the imaginary part of the complex number; , , are the steady-state positive-sequence short-circuit current, active component and reactive component corresponding to the new energy node p in the kth cycle under the i-th transition resistance; , , They are respectively the steady-state negative-sequence short-circuit current amplitude, active component and reactive component of the plant corresponding to the new energy node p after the current new energy bus fails; the superscript i represents the number of iterations of the i-th transition resistance; the superscript k represents the number of times the new energy fault current is injected into the current new energy bus; the subscript d represents the active component of the current; the subscript q represents the reactive component of the current; the subscript 1 represents the positive-sequence current; the subscript 2 represents the negative-sequence current; To reflect the new energy current and positive sequence voltage controlled by its terminal voltage Function of To reflect the new energy current and negative sequence voltage controlled by its terminal voltage Function of The second current parameter is specifically: If the fault is a single-phase grounding fault, then: in, is the positive sequence short-circuit current of the fault node in the kth cycle of the new energy under the i-th transition resistance, is the negative sequence short-circuit current of the fault node in the kth cycle of the new energy under the i-th transition resistance, is the positive sequence impedance of the fault node f, is the zero-sequence impedance of the fault node f, is the grounding resistance of the single-phase short-circuit fault in the i-th cycle, is the positive sequence mutual impedance between the fault node f and the new energy node p; If the fault is a two-phase fault, then: If the fault is a two-phase grounding fault, then: Among them, / / represents AND operation; If the fault is a three-phase phase-to-phase fault, the positive sequence current and negative sequence current of the fault node are: 。 4. According to claim 1, a method for external characteristic aggregation equivalent interaction of a new energy gathering area is characterized in that: The first voltage parameter is specifically: in, is the positive sequence voltage of the new energy node p in the kth cycle of the new energy under the i-th transition resistance, is the negative sequence voltage of the new energy node p in the kth cycle of the new energy under the i-th transition resistance, is the zero-sequence voltage of the new energy node p in the kth cycle of the new energy under the i-th transition resistance, , are the positive-sequence and negative-sequence self-impedances of the new energy node p, respectively. is the negative sequence short-circuit current provided by the new energy node p for the kth time in the i-th cycle, is the zero-sequence short-circuit current provided by the fault node f in the kth cycle of the new energy under the i-th transition resistance, is the negative sequence mutual impedance between the fault node f and the new energy node p, is the zero-sequence mutual impedance between the fault node f and the new energy node p; The second voltage parameter is specifically: in, , Faulty nodes The positive and negative sequence self-impedance.

5. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 4 are implemented.

6. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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