New energy cluster grid-connected system intensity quantification method and system

Abstract

The invention provides a new energy cluster grid-connected system intensity quantification method and system, and the method comprises the steps: firstly obtaining an equivalent admittance matrix model of a new energy cluster topology, carrying out the transformation processing of the equivalent admittance matrix model, and determining a first equivalent node impedance matrix model; secondly, obtaining the equivalent impedance Z0 of the network building type unit and the serial number k of a node to be accessed, correcting the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the serial number k of the node to be accessed, and determining a second equivalent node impedance matrix model; and finally, obtaining the rated voltage and rated power of each new energy station in the new energy cluster topology, and determining the node voltage deviation degree of each new energy station based on the second equivalent node impedance matrix model. According to the method, the system strength can be quantified through the node voltage deviation index, so that powerful data support is provided for better improving the system strength of a new energy cluster station.

Description

Technical Field

[0001] The present application relates to the technical field of electric power, and particularly to a method and system for quantifying the strength of a new energy cluster grid-connected system. Background Art

[0002] With the rapid increase in the penetration rate of new energy, the power system is gradually shifting from a traditional structure dominated by synchronous machines to an electrified power system, but this also leads to an increasingly prominent problem of the weakening of the strength of the new power system. System strength is usually defined as the ability of the power grid to maintain voltage stability, especially the ability to maintain the node voltage amplitude and waveform quality during faults or power fluctuations.

[0003] New energy units are grid-connected through converters, and there are essential differences between their current source characteristics and the voltage source characteristics of traditional synchronous machines, resulting in a decrease in system inertia and short-circuit capacity after a high proportion of new energy is connected, and further causing problems such as voltage instability and oscillation. The voltage strength of the power system has become the core bottleneck restricting the consumption of new energy and the safe and stable operation of the system. In this context, the grid-forming (GFM) converter is regarded as the key means to enhance system strength due to its ability to independently construct grid voltage and frequency.

[0004] However, due to the large-scale grid connection of renewable energy, the complexity of the new energy cluster network structure and the heterogeneity of new energy units lead to different configuration capacities and spatial distributions of grid-forming units in the new energy cluster, resulting in different improvement effects on the system strength of different substation nodes in the cluster. At the same time, due to the asymmetry of the network structure, the evaluation index of the new energy cluster system strength is difficult to evaluate through simple traditional indexes. Summary of the Invention

[0005] Based on this, it is necessary to provide a method and system for quantifying the strength of a new energy cluster grid-connected system for the above technical problems.

[0006] A method for quantifying the strength of a new energy cluster grid-connected system includes:

[0007] Obtain an equivalent admittance matrix model of the new energy cluster topology, perform transformation processing on the equivalent admittance matrix model, and determine a first equivalent node impedance matrix model;

[0008] Obtain the equivalent impedance Z0 of the grid-forming unit and the node number k to be connected, correct the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the node number k to be connected, and determine a second equivalent node impedance matrix model;

[0009] Obtain the rated voltage and rated power of each new energy substation in the new energy cluster topology, and determine the node voltage deviation degree of each new energy substation based on the second equivalent node impedance matrix model.

[0010] In one embodiment, the steps of obtaining an equivalent admittance matrix model of the new energy cluster topology and performing transformation processing on the equivalent admittance matrix model to determine a first equivalent nodal impedance matrix model include:

[0011] Obtain an equivalent admittance matrix model of the new energy cluster topology;

[0012] Perform order reduction and elimination and inversion processing on the equivalent admittance matrix model to determine a first equivalent nodal impedance matrix model, where the first equivalent nodal impedance matrix model is:

[0013]

[0014] where U RE1 、U RE2 、…、U REn are the grid-connected bus node voltages of each power station in the new energy cluster, I1, I2, …, I n are the currents injected into the AC system by the grid-connected buses, and Z eqij is the element in the i-th row and j-th column of the first equivalent nodal impedance matrix model Z eq at the new energy grid-connected bus, and i and j are positive integers.

[0015] In one embodiment, the steps of performing order reduction and elimination and inversion processing on the equivalent admittance matrix model to determine a first equivalent nodal impedance matrix model include:

[0016] Perform order reduction processing on the equivalent admittance matrix model, and the processing method is as follows:

[0017]

[0018] where k is the number of a certain node in the new energy cluster;

[0019] Perform elimination and inversion processing on the equivalent admittance matrix model after order reduction processing to determine a first equivalent nodal impedance matrix model.

[0020] In one embodiment, the steps of obtaining the equivalent impedance Z0 of the network-forming unit and the number k of the node to be connected, correcting the first equivalent nodal impedance matrix model based on the equivalent impedance Z0 and the number k of the node to be connected, and determining a second equivalent nodal impedance matrix model include:

[0021] Obtain the equivalent impedance Z0 of the network-forming unit and the number k of the node to be connected;

[0022] Correct the first equivalent nodal impedance matrix model based on the equivalent impedance Z0 and the number k of the node to be connected, and determine that the second equivalent nodal impedance matrix model is:

[0023]

[0024] Among them, Z eq is the first equivalent node impedance matrix model.

[0025] In one embodiment, the step of obtaining the rated voltage and rated power of each new energy station in the new energy cluster topology and determining the node voltage deviation degree of each new energy station based on the second equivalent node impedance matrix model includes:

[0026] Obtain the rated voltage and rated power of each new energy station in the new energy cluster topology;

[0027] Based on the second equivalent node impedance matrix model, the node voltage deviation degree of each new energy station is determined as:

[0028]

[0029] Among them, NVDR i ˊ is the node voltage deviation degree, U N is the rated voltage of the new energy station, P RE is the rated power of the new energy station, and i and j are positive integers.

[0030] In one embodiment, the method for quantifying the strength of the new energy cluster grid-connected system further includes:

[0031] When the grid-forming unit is not connected, based on the first equivalent node impedance matrix model, the node voltage deviation degree is determined as:

[0032]

[0033] Among them, U Ni is the rated voltage of the i-th grid-connected bus node, U REi is the voltage generated at the i-th node after the new energy station is connected, and I i is the short-circuit current provided by the i-th new energy station.

[0034] A new energy cluster grid-connected system strength quantification system includes:

[0035] A processing module, configured to obtain an equivalent admittance matrix model of the new energy cluster topology, perform transformation processing on the equivalent admittance matrix model, and determine a first equivalent node impedance matrix model;

[0036] A correction module, connected to the processing module, for obtaining the equivalent impedance Z0 of the network-forming unit and the node number k to be connected, correcting the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the node number k to be connected, and determining a second equivalent node impedance matrix model;

[0037] A calculation module, connected to the correction module, for obtaining the rated voltage and rated power of each new energy station in the new energy cluster topology, and determining the node voltage deviation of each new energy station based on the second equivalent node impedance matrix model.

[0038] In one embodiment, determining the node voltage deviation of each new energy station based on the second equivalent node impedance matrix model is

[0039]

[0040] where NVDR i ˊ is the node voltage deviation, U N is the rated voltage of the new energy station, P RE is the rated power of the new energy station, and i and j are positive integers.

[0041] A computer device, including a memory and a processor, where the memory stores a computer program, and when the processor executes the computer program, the steps of the method described in any one of the above embodiments are implemented.

[0042] A computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the method described in any one of the above embodiments are implemented.

[0043] Compared with the prior art, in the above method and system for quantifying the grid connection system strength of a new energy cluster, first, an equivalent admittance matrix model of the new energy cluster topology is obtained, and the equivalent admittance matrix model is transformed to determine a first equivalent node impedance matrix model; secondly, the equivalent impedance Z0 of the network-forming unit and the node number k to be connected are obtained, and the first equivalent node impedance matrix model is corrected based on the equivalent impedance Z0 and the node number k to be connected, and a second equivalent node impedance matrix model is determined; finally, the rated voltage and rated power of each new energy station in the new energy cluster topology are obtained, and the node voltage deviation of each new energy station is determined based on the second equivalent node impedance matrix model. By adopting the above method, the system strength can be quantified through the node voltage deviation index, thereby providing strong data support for better improving the system strength of new energy cluster stations. Description of the Drawings

[0044] To more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0045] Figure 1 Flowchart of the method for quantifying the strength of a new energy cluster grid connection system provided by an embodiment of the present application;

[0046] Figure 2 Schematic diagram of a simplified model of an AC system with multiple new energy power stations connected provided by an embodiment of the present application;

[0047] Figure 3 Schematic diagram of an equivalent model of a new energy multi-station grid connection system provided by an embodiment of the present application;

[0048] Figure 4 Schematic diagram of an equivalent model of system nodes after a grid-forming unit is connected provided by an embodiment of the present application;

[0049] Figure 5 Block diagram of the structure of a system for quantifying the strength of a new energy cluster grid connection system provided by an embodiment of the present application;

[0050] Figure 6 Internal structure diagram of a computer device provided by an embodiment of the present application.

[0051] Explanation of reference numerals:

[0052] 10. System for quantifying the strength of a new energy cluster grid connection system; 100. Processing module; 200. Correction module; 300. Calculation module. Detailed implementation manners

[0053] To make the above objects, features, and advantages of the present application more obvious and understandable, the following will provide a detailed description of the specific implementation manners of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein. Those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific implementations disclosed below.

[0054] The serial numbers assigned to the components in this text itself, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequential or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, both include direct and indirect connection (coupling). In the description of this application, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing this application 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 to this application.

[0055] In this application, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0056] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time.

[0057] Unless otherwise defined, all technical and scientific terms used in this text have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this text includes any and all combinations of one or more of the related listed items.

[0058] Please refer to Figure 1 , an embodiment of this application provides a method for quantifying the strength of a new energy cluster grid connection system.

[0059] For a new energy power station cluster, the connection structure between each power station is complex, and it is difficult to obtain the form of a single-feed AC system through a simple equivalent transformation process. Therefore, first, it is necessary to equivalent the complex structure in the new energy multi-power station cluster, so as to analyze the change range of the node voltages of each power station in the new energy cluster before and after power perturbation, and reflect the system strength of the grid connection points of each power station.

[0060] The AC system with new energy access can be simplified into an ideal voltage source in series with an equivalent impedance by using the Thevenin equivalent method. Then, for a multi-port controlled power network, such as the new energy multi-station cluster topology network, by using the multi-port Thevenin equivalent, the external network of each new energy station node can be equivalently transformed into the form of a single-fed AC system, and the simplified equivalent model schematic diagram of i (i = 1, 2,..., n) new energy stations accessing the AC system as shown in Figure 2 can be obtained. Among them, S Rei , P Rei , Q REi , and U REi are the apparent power, active power, reactive power, and grid-connected bus voltage of the new energy power generation equipment / station i respectively; Z ij is the equivalent impedance between grid connection points i and j; Z i is the system-side equivalent impedance between the main grid equivalent power source i and the corresponding grid connection point. For the Figure 2 multi-station grid-connected system shown, assuming that the equivalent model of a new energy grid-connected system containing 7 new energy stations is as shown in Figure 3 , the voltage nodes in the grid-connected system are numbered. Among them, ① is the grid connection node between the large power grid and the new energy system, ⑤ is the common node in the system, and the rest are the grid connection nodes of the new energy stations, that is, the high-voltage side nodes of the step-up transformers of the new energy stations.

[0061] The method for quantifying the strength of the new energy cluster grid-connected system includes:

[0062] S102: Obtain the equivalent admittance matrix model of the new energy cluster topology, and perform transformation processing on the equivalent admittance matrix model to determine the first equivalent node impedance matrix model.

[0063] In some embodiments, the equivalent admittance matrix model of the new energy cluster topology can be obtained by a processor or a controller, and transformation processing is performed on the equivalent admittance matrix model to determine the first equivalent node impedance matrix model. The first equivalent node impedance matrix model is Equation 1:

[0064]

[0065] where U RE1 , U RE2 , …, U REn are the grid-connected bus node voltages of each station in the new energy cluster, I1, I2, …, I n are the currents injected into the AC system by the grid-connected buses, Z eqij is the element in the i-th row and j-th column of the first equivalent node impedance matrix model Z eq at the new energy grid-connected bus, and i and j are positive integers.

[0066] S104: Obtain the equivalent impedance Z0 of the network-forming unit and the node number k to be connected, correct the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the node number k to be connected, and determine the second equivalent node impedance matrix model.

[0067] In some embodiments, the equivalent impedance Z0 of the network-forming unit and the node number k to be connected can be obtained by a processor or a controller. The first equivalent node impedance matrix model is corrected based on the equivalent impedance Z0 and the node number k to be connected, and the second equivalent node impedance matrix model is determined. In some embodiments, the access of a new energy power station to a network-forming unit can be equivalent to connecting an equivalent impedance Z0 in series at the grid connection point of the power station. For the first equivalent node impedance matrix model Z eq , after the network-forming unit is connected, it is equivalent to connecting a branch to ground Z0 in parallel at node k, and its schematic diagram is as Figure 4 shown.

[0068] Based on the branch addition principle of the first equivalent node impedance matrix model Z eq , if a grounding link branch Z0 is added to node k of the original network, without changing the dimension of the first equivalent node impedance matrix model Z eq , the node impedance elements in the first equivalent node impedance matrix model should be corrected based on the equivalent impedance Z0 and the node number k to be connected, so as to determine the second equivalent node impedance matrix model.

[0069] S106: Obtain the rated voltage and rated power of each new energy power station in the new energy cluster topology, and determine the node voltage deviation degree of each new energy power station based on the second equivalent node impedance matrix model.

[0070] In some embodiments, the rated voltage and rated power of each new energy power station in the new energy cluster topology can be obtained by a processor or a controller, and the node voltage deviation degree of each new energy power station is determined based on the second equivalent node impedance matrix model. Specifically, after the network-forming unit is connected and the second equivalent node impedance matrix model is determined, the node voltage deviation degree at the node of the i-th new energy power station can be determined based on the rated voltage and rated power of the corresponding power station, which can be expressed as Equation 2:

[0071]

[0072] where NVDR i ˊ is the Node Voltage Deviation Ratio (NVDR), U N is the rated voltage of the new energy power station, and P REis the rated power of the new energy power station, and i and j are positive integers. It can be seen from the above formula that after the grid-forming unit is connected, the NVDR of the new energy power station i ˊ decreases, and the system strength is enhanced. By adopting the above method in this embodiment, the system strength can be quantified by the node voltage deviation index, thereby providing strong data support for better enhancing the system strength of the new energy cluster power station.

[0073] In some embodiments, the steps of obtaining the equivalent admittance matrix model of the new energy cluster topology and performing transformation processing on the equivalent admittance matrix model to determine the first equivalent node impedance matrix model include: obtaining the equivalent admittance matrix model of the new energy cluster topology; performing order reduction and elimination and inversion processing on the equivalent admittance matrix model to determine the first equivalent node impedance matrix model.

[0074] In some embodiments, according to the equivalent admittance matrix model Y of the AC power grid sys , only the grid-connected bus nodes of each power station, the grid-connected nodes with the large power grid, the common nodes in the system, etc. are retained in the matrix model. Since there is no direct connection to the power source, the current injection on the bus is always zero, and such nodes can be eliminated by a certain method. Specifically, for a certain node k in the system (i.e., k is the number of a certain node in the new energy cluster), if the current injected into node k is zero, substituting it into the node voltage equation matrix, the elements of the non-k rows and non-k columns in the node admittance matrix model can be recalculated, thereby forming a new (k - 1)-order matrix model. After transformation, the dimension of the system admittance matrix becomes lower, and some nodes in the system are eliminated. In a system with n bus nodes, the simplified admittance matrix of the system after eliminating node k can be calculated by the following formula 3:

[0075]

[0076] where k is the number of a certain node in the new energy cluster.

[0077] Performing elimination and inversion processing on the equivalent admittance matrix model after order reduction processing, the equivalent impedance matrix model Z of the AC power grid at the new energy grid-connected bus can be obtained eq (i.e., the first equivalent node impedance matrix model).

[0078] In some embodiments, when the grid-forming unit is not connected, based on the equivalent impedance matrix model Z of the AC power grid eq , an index based on the relative relationship between the system voltage and the rated node voltage after the new energy power station is connected is defined. The node voltage deviation (i.e., the system strength index) of the i-th power station in the system is formula 4:

[0079]

[0080] Among them, U Ni is the rated voltage of the i-th grid-connected bus node, and U REi is the voltage generated at the i-th node after the new energy power station is connected. I i is the short-circuit current provided by the i-th new energy power station, and i is a positive integer.

[0081] In some embodiments, the new energy units in the new energy power station are stepped up by a transformer. The voltage level at the grid connection point of the power station is generally 220 kV. In the system, the reactance of the impedance parameter is usually greater than the resistance. Then, Equation 4 can be simplified to Equation 5:

[0082]

[0083] Among them, P Rei is the active power injected by the new energy power station at node i.

[0084] In some embodiments, let the actual operating voltage of the i-th grid-connected bus node of the new energy power station be U i , multiply both the numerator and denominator in Formula 3 by to obtain Equation 6:

[0085]

[0086] Among them, is the conjugate value of the voltage of the i-th grid-connected node, and S REi is the actual apparent power of the new energy injected at the i-th new energy grid-connected bus node.

[0087] In some embodiments, taking U i as the reference voltage and the rated capacity of node i as the reference power, then Equation 6 can be simplified to Equation 7:

[0088]

[0089] Among them, P i , P j , Z ii , Z ij respectively represent the per-unit values of P REi , P REj , Z eqii , Z eqij .

[0090] It can be seen from the simplified Equation 7 that with the continuous grid connection and operation of a large amount of new energy, the greater the impact on the power grid system, the greater the NVDR, and the weaker the support ability of the power grid system, that is, the weaker the system strength. Thus, the node voltage offset of multiple new energy power stations at the machine terminal can be used to evaluate the system strength of the new energy power station.

[0091] In some embodiments, the steps of obtaining the equivalent impedance Z0 of the network-forming unit and the node number k to be connected, modifying the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the node number k to be connected, and determining the second equivalent node impedance matrix model include: obtaining the equivalent impedance Z0 of the network-forming unit and the node number k to be connected; modifying the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the node number k to be connected, and determining the second equivalent node impedance matrix model as Equation 8:

[0092]

[0093] where Z eq is the first equivalent node impedance matrix model.

[0094] Specifically, it can be seen from Equation 8 that when a network-forming unit is added to a new energy power station, all elements in the system node impedance matrix Z eq will decrease, and among them, the matrix element Z eqkk corresponding to the grid-connected node of the power station where the network-forming unit is connected decreases the most.

[0095] In some embodiments, assuming that the node voltages of each power station in the cluster are equal, i.e., |U i | = |U j |, and the voltage phase angles between new energy power stations are the same, then the NVDR of the grid-connected system i , that is, Equation 5 can be expressed as Equation 9:

[0096]

[0097] After the network-forming unit is connected, the node impedance matrix Z eq (i.e., the first equivalent node impedance matrix model) changes. Assuming that the node where the network-forming unit is connected is k, substituting Equation 8 into Equation 9, then the NVDR i at the i-th new energy power station node can be expressed as Equation 10:

[0098]

[0099] where NVDR i ˊ is the node voltage deviation, U N is the rated voltage of the new energy power station, P RE is the rated power of the new energy power station, and i and j are positive integers.

[0100] Comparing with Equation 9, it can be seen that after the network-forming unit is connected, the NVDR of the new energy power station decreases and the system strength increases.

[0101] Please refer to Figure 5, an embodiment of the present application provides a new energy cluster grid connection system strength quantification system 10. The new energy cluster grid connection system strength quantification system 10 includes: a processing module 100, a correction module 200, and a calculation module 300. The processing module 100 is used to obtain an equivalent admittance matrix model of the new energy cluster topology, perform transformation processing on the equivalent admittance matrix model, and determine a first equivalent node impedance matrix model. The correction module 200 is connected to the processing module 100. The correction module 200 is used to obtain the equivalent impedance Z0 of the network-forming unit and the node number k to be connected, correct the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the node number k to be connected, and determine a second equivalent node impedance matrix model. The calculation module 300 is connected to the correction module 200. The calculation module 300 is used to obtain the rated voltage and rated power of each new energy station in the new energy cluster topology, and determine the node voltage deviation degree of each new energy station based on the second equivalent node impedance matrix model.

[0102] In some embodiments, the specific structure of the processing module 100 is not limited, as long as it has the function of obtaining an equivalent admittance matrix model of the new energy cluster topology, performing transformation processing on the equivalent admittance matrix model, and determining a first equivalent node impedance matrix model. Specifically, the processing module 100 can be a controller, a processor, etc. The specific structure of the processing module 100 can be selected according to actual needs and is not specifically limited here.

[0103] In some embodiments, the specific structure of the correction module 200 is not limited, as long as it has the function of obtaining the equivalent impedance Z0 of the network-forming unit and the node number k to be connected, correcting the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the node number k to be connected, and determining a second equivalent node impedance matrix model. Specifically, the correction module 200 can be a microprocessor or an integrated controller, etc. The specific structure of the correction module 200 can be selected according to actual needs and is not specifically limited here.

[0104] In some embodiments, the specific structure of the calculation module 300 is not limited, as long as it has the function of obtaining the rated voltage and rated power of each new energy station in the new energy cluster topology, and determining the node voltage deviation degree of each new energy station based on the second equivalent node impedance matrix model. Specifically, the calculation module 300 can be a microprocessor or an integrated controller, etc. The specific structure of the calculation module 300 can be selected according to actual needs and is not specifically limited here.

[0105] In this embodiment, by adopting the above method, the system strength can be quantified through the node voltage deviation index, thus providing strong data support for better improving the system strength of new energy cluster power stations.

[0106] In some embodiments, a computer device is provided. The computer device can be a terminal, and its internal structure diagram can be as Figure 6 shown. The computer device includes a processor, a memory, a network interface, a display screen, and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, it realizes a method for quantifying the system strength of a new energy cluster grid-connected system. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer covered on the display screen, or a button, a trackball, or a touchpad provided on the housing of the computer device, or an external keyboard, a touchpad, or a mouse, etc.

[0107] Those skilled in the art can understand that Figure 6 the structure shown in

[0108] is only a block diagram of some structures related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements. Figure 6 Please refer to

[0109] In one embodiment, when the processor executes the computer program, the following steps are implemented:

[0110] S102: Obtain the equivalent admittance matrix model of the new energy cluster topology, perform transformation processing on the equivalent admittance matrix model, and determine the first equivalent node impedance matrix model;

[0111] S104: Obtain the equivalent impedance Z0 of the network-forming unit and the node number k to be connected, correct the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the node number k to be connected, and determine the second equivalent node impedance matrix model;

[0112] S106: Obtain the rated voltage and rated power of each new energy power station in the new energy cluster topology, and determine the node voltage deviation degree of each new energy power station based on the second equivalent node impedance matrix model.

[0113] An embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the new energy cluster grid-connected system strength quantification method described in any one of the above embodiments are implemented.

[0114] In one embodiment, when the computer program is executed by a processor, the following steps are implemented:

[0115] S102: Obtain the equivalent admittance matrix model of the new energy cluster topology, perform transformation processing on the equivalent admittance matrix model, and determine the first equivalent node impedance matrix model;

[0116] S104: Obtain the equivalent impedance Z0 of the network-forming unit and the node number k to be connected. Based on the equivalent impedance Z0 and the node number k to be connected, correct the first equivalent node impedance matrix model, and determine the second equivalent node impedance matrix model;

[0117] S106: Obtain the rated voltage and rated power of each new energy power station in the new energy cluster topology, and determine the node voltage deviation degree of each new energy power station based on the second equivalent node impedance matrix model.

[0118] The above computer device and computer-readable storage medium, by adopting the above method, can quantify the system strength through the node voltage deviation degree index, thereby providing strong data support for better improving the system strength of the new energy cluster power stations.

[0119] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the embodiments provided in the present application can include non-volatile and / or volatile memories. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0120] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0121] The above embodiments only represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method for quantifying the strength of a new energy cluster grid-connected system, characterized in that: include: Obtaining an equivalent admittance matrix model of the new energy cluster topology, transforming the equivalent admittance matrix model, and determining a first equivalent node impedance matrix model; Obtaining the equivalent impedance Z0 of the grid-type unit and the number k of the node to be connected, modifying the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the number k of the node to be connected, and determining the second equivalent node impedance matrix model; The rated voltage and rated power of each new energy station in the new energy cluster topology are obtained, and the node voltage deviation of each new energy station is determined based on the second equivalent node impedance matrix model.

2. The method for quantifying the strength of a new energy cluster grid-connected system according to claim 1, characterized in that: The step of obtaining an equivalent admittance matrix model of the new energy cluster topology, transforming the equivalent admittance matrix model, and determining a first equivalent node impedance matrix model comprises: Obtain the equivalent admittance matrix model of the new energy cluster topology; The equivalent admittance matrix model is subjected to order reduction and elimination inversion processing to determine a first equivalent node impedance matrix model, wherein the first equivalent node impedance matrix model is: Among them, U RE1 , U RE2 , …, U REn is the grid-connected bus node voltage of each station in the new energy cluster, I1, I2, ..., I n The current injected into the AC system for the grid-connected bus, Z eqij The first equivalent node impedance matrix model Z at the new energy grid-connected bus eq The i-th row and j-th column element of , where i and j are positive integers.

3. The method for quantifying the strength of a new energy cluster grid-connected system according to claim 2, characterized in that: The step of performing order reduction and elimination inversion processing on the equivalent admittance matrix model to determine the first equivalent node impedance matrix model comprises: The equivalent admittance matrix model is reduced in order as follows: Among them, k is the number of a node in the new energy cluster; The equivalent admittance matrix model after the order reduction processing is subjected to elimination and inversion processing to determine the first equivalent node impedance matrix model.

4. The method for quantifying the strength of a new energy cluster grid-connected system according to claim 1, characterized in that: The steps of obtaining the equivalent impedance Z0 of the grid-type unit and the number k of the node to be connected, modifying the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the number k of the node to be connected, and determining the second equivalent node impedance matrix model include: Obtain the equivalent impedance Z0 of the grid-forming unit and the node number k to be connected; The first equivalent node impedance matrix model is modified based on the equivalent impedance Z0 and the node number k to be connected, and the second equivalent node impedance matrix model is determined as: Among them, Z eq It is the first equivalent node impedance matrix model.

5. The method for quantifying the strength of a new energy cluster grid-connected system according to claim 1, characterized in that: The step of obtaining the rated voltage and rated power of each new energy station in the new energy cluster topology, and determining the node voltage deviation of each new energy station based on the second equivalent node impedance matrix model includes: Obtaining the rated voltage and rated power of each new energy station in the new energy cluster topology; Based on the second equivalent node impedance matrix model, the node voltage deviation of each new energy station is determined as: Among them, NVDR i ˊ is the node voltage deviation, U N is the rated voltage of the new energy station, P RE is the rated power of the new energy station, i and j are positive integers.

6. The method for quantifying the strength of a new energy cluster grid-connected system according to claim 5, characterized in that: The method further comprises: When the grid-type unit is not connected, the node voltage deviation is determined based on the first equivalent node impedance matrix model as: Among them, U Ni is the rated voltage of the ith grid-connected bus node, U REi is the voltage generated at the i-th node after the new energy station is connected, I i The short-circuit current provided for the i-th new energy station.

7. A new energy cluster grid-connected system strength quantification system, characterized in that: include: A processing module, used for obtaining an equivalent admittance matrix model of the new energy cluster topology, transforming the equivalent admittance matrix model, and determining a first equivalent node impedance matrix model; A correction module connected to the processing module, the correction module is used to obtain the equivalent impedance Z0 of the grid-type unit and the node number k to be connected, correct the first equivalent node impedance matrix model based on the equivalent impedance Z0 and the node number k to be connected, and determine the second equivalent node impedance matrix model; A calculation module is connected to the correction module, and the calculation module is used to obtain the rated voltage and rated power of each new energy site in the new energy cluster topology, and determine the node voltage deviation of each new energy site based on the second equivalent node impedance matrix model.

8. The new energy cluster grid-connected system strength quantification system according to claim 7, characterized in that: The node voltage deviation of each new energy station is determined based on the second equivalent node impedance matrix model: Among them, NVDR i ˊ is the node voltage deviation, U N is the rated voltage of the new energy station, P RE is the rated power of the new energy station, i and j are positive integers.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, 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 7 are implemented.

Images