Method for judging the degree of reactive power imbalance in new energy stations

Abstract

This application provides a method for determining the degree of reactive power imbalance in a renewable energy power station. The method includes: obtaining a reference value and an actual value of reactive power for the renewable energy substation; and establishing an evaluation system for the reactive power imbalance of the renewable energy substation based on the reference value and the actual value. The method for determining the degree of reactive power imbalance in the renewable energy power station provides a quantitative evaluation of the degree of reactive power imbalance based on the evaluation system.

Description

Technical Field

[0001] The present application relates to the field of power system operation, and in particular to a method for determining the degree of reactive power imbalance of a new energy station. Background Art

[0002] In the actual operation of the power grid, secondary voltage control is used to control some key nodes in the region to maintain the voltage level in the region. When the AVC (Auto Voltage Control) master station controls each substation in the region, it sends a voltage adjustment instruction to each substation in the region. Each substation adjusts reactive power according to the voltage instruction value in the adjustment instruction and tracks the voltage instruction value. When the substation voltage reaches the voltage instruction value requirement, it is generally required that each substation in the region share reactive power according to the electrical distance between the substation and the central node to achieve a balanced reactive power sharing.

[0003] In actual cluster reactive voltage control, after the AVC master station sends adjustment instructions to each substation, due to differences in control strategies, electrical parameters, and response performance of each substation, there is a large deviation between the reactive power output of each substation during the execution of the adjustment instruction and the reference value in the adjustment instruction sent by the AVC master station. The adjustment rates between substations are different, resulting in some substations bearing a large reactive power output, while the remaining substations bear almost no reactive power output, resulting in an unbalanced reactive power distribution. In this case, it is necessary to make a secondary adjustment to the reactive power of the power grid system. However, there is no accurate quantitative definition of the reactive power imbalance phenomenon in current research, and the power grid system cannot accurately obtain the reactive power imbalance signal and thus cannot make a secondary adjustment to the reactive power of the power grid system. Summary of the invention

[0004] Based on this, the present invention proposes a method for determining the degree of reactive power imbalance of a new energy station, so as to make a quantitative evaluation of the degree of reactive power imbalance of the new energy station.

[0005] A method for determining the degree of reactive power imbalance of a new energy station, wherein the new energy station includes a plurality of new energy substations, and the method includes:

[0006] Obtaining a reactive power reference value of the new energy substation;

[0007] Obtaining the actual value of reactive power of the new energy substation;

[0008] Establishing an evaluation system for reactive power imbalance of the new energy substation according to the reactive power reference value and the reactive power actual value of the new energy substation;

[0009] The imbalance degree of reactive power of the new energy substation is determined based on the evaluation system.

[0010] In one embodiment, the new energy substation includes a generator and a reactive power compensator, and obtaining the reactive power reference value of the new energy substation includes:

[0011] Obtaining the initial value of reactive power of the generator node and the reactive power compensator node;

[0012] Obtaining reactive power changes of the generator node and the reactive power compensator node;

[0013] Calculating the reactive power reference value of the generator node according to the reactive power change and the initial reactive power value of the generator node, and calculating the reactive power reference value of the reactive compensator node according to the reactive power change and the initial reactive power value of the reactive compensator node;

[0014] The generator node is the connection point between the generator and the power grid, and the reactive power compensator node is the connection point between the reactive power compensator and the power grid; the power grid is connected to the new energy substation.

[0015] In one embodiment, the new energy site further includes a new energy master station, the new energy master station is connected to the power grid, and the acquiring of reactive power changes of the generator node and the reactive compensator node includes:

[0016] Establishing a reactive power sensitivity matrix of the new energy substation;

[0017] Acquire the voltage change of the new energy master station according to the reactive power sensitivity matrix;

[0018] Acquire voltage changes of the generator node and the reactive power compensator node according to the reactive power sensitivity matrix;

[0019] The reactive power change of the generator node is calculated according to the reactive power sensitivity matrix, the voltage change of the new energy master station and the voltage change of the generator node; the reactive power change of the reactive compensator node is calculated according to the reactive power sensitivity matrix, the voltage change of the new energy master station and the voltage change of the reactive compensator node.

[0020] In one embodiment, the power grid includes a load node, and establishing the reactive power sensitivity matrix of the new energy substation includes:

[0021] Establishing an iterative equation according to the reactive power variation of the generator node and the reactive compensator node, the voltage variation of the generator node and the reactive compensator node, the voltage variation of the new energy master station, the voltage variation of the load node and a sensitivity parameter;

[0022] The reactive power sensitivity matrix is ​​obtained by simplifying and transforming the iterative equation.

[0023] In one embodiment, acquiring the voltage variation of the generator node and the reactive compensator node according to the reactive power sensitivity matrix comprises:

[0024] Acquiring initial voltage values ​​of the generator node and the reactive power compensator node;

[0025] Establishing a voltage optimization power flow model according to the reactive power sensitivity matrix;

[0026] Acquiring voltage reference values ​​of the generator node and the reactive power compensator node according to the voltage optimization power flow model;

[0027] The voltage variation of the generator node is calculated according to the voltage initial value of the generator node and the voltage reference value of the generator node, and the voltage variation of the reactive compensator node is calculated according to the voltage initial value of the reactive compensator node and the voltage reference value of the reactive compensator node.

[0028] In one embodiment, the evaluation system includes quantitative evaluation indicators of each of the new energy substations and quantitative evaluation indicators of the new energy substation as a whole, and the evaluation system for establishing reactive power imbalance of the new energy substation based on the reactive power reference value and the reactive power actual value of the new energy substation includes:

[0029] Calculating a quantitative evaluation index of each of the new energy substations according to a reactive power reference value and an actual reactive power value of the new energy substation;

[0030] The overall quantitative evaluation index of the new energy substation is calculated according to the reactive power reference value and the reactive power actual value of the new energy substation.

[0031] In one embodiment, the quantitative evaluation indexes of each of the new energy substations include: reactive power deviation, reactive power deviation ratio and reactive power deviation capacity ratio.

[0032] In one embodiment, the overall quantitative evaluation index of the new energy substation includes: an overall reactive power deviation ratio and a maximum reactive power deviation ratio.

[0033] In one embodiment, determining the imbalance degree of reactive power of the new energy substation based on the evaluation system includes:

[0034] When the reactive power deviation ratio is greater than a first preset value, and the reactive power deviation capacity ratio is greater than a second preset value, the reactive power of the new energy substation is unbalanced;

[0035] When the overall reactive power deviation ratio is greater than the third preset value, and the maximum reactive power deviation ratio is greater than the fourth preset value, the overall reactive power of the new energy substation is unbalanced.

[0036] A device for judging the degree of reactive power imbalance of a new energy station, wherein the new energy station includes multiple new energy substations, and the judging device includes: a data acquisition module, used to obtain the actual value of reactive power of the new energy substation; a data processing module, used to obtain the reactive power reference value of the new energy substation, and establish an evaluation system for reactive power imbalance of the new energy substation according to the reactive power reference value and the actual value of reactive power of the new energy substation; and a judging module, used to judge the degree of reactive power imbalance of the new energy substation based on the evaluation system.

[0037] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the method described in any one of the above embodiments when executing the computer program.

[0038] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the method described in any one of the above embodiments.

[0039] The method for judging the degree of reactive power imbalance of the new energy station provided in the present application obtains the reactive power reference value and the reactive power actual value of the reactive power of the new energy substation, and establishes an evaluation system for the reactive power imbalance of the new energy substation according to the reactive power reference value and the reactive power actual value of the new energy substation. The method for judging the degree of reactive power imbalance of the new energy station makes a quantitative evaluation of the degree of reactive power imbalance of the new energy station according to the evaluation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 The diagram is an application environment of a method for determining the degree of reactive power imbalance in a new energy station in an embodiment.

[0041] Figure 2 It is a flowchart of a method for determining the degree of reactive power imbalance of a new energy station in one embodiment.

[0042] Figure 3 It is a flowchart of the steps of obtaining the reactive power reference value of the new energy substation in an embodiment.

[0043] Figure 4 It is a flowchart of the steps of obtaining the reactive power change of the generator node and the reactive power compensator node in an embodiment.

[0044] Figure 5 It is an initial status table of a new energy station in one embodiment.

[0045] Figure 6 It is a reactive power deviation index table of a new energy substation in one embodiment.

[0046] Figure 7 It is a reactive power deviation index table of a new energy substation in another embodiment. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0048] The method for determining the degree of reactive power imbalance of a new energy station provided in this application can be applied to Figure 1 In the application environment shown. Among them, the new energy station includes multiple new energy substations and a new energy main station. The new energy main station is also called a key node. The multiple new energy substations and the new energy main station are connected to the power grid. The new energy substation can be a wind farm. The key node is the node where the wind farm is centrally integrated into the power grid. The key node needs to control the voltage by changing the output of reactive power through the new energy substation to maintain the voltage stability of the key node.

[0049] In one embodiment, Figure 2 As shown, a method for judging the degree of reactive power imbalance in a new energy station is provided. The method is applied to Figure 1 The application environment in the example is used to illustrate the following steps:

[0050] S10, obtaining a reactive power reference value of the new energy substation;

[0051] S20, obtaining the actual value of reactive power of the new energy substation;

[0052] S30, establishing an evaluation system for reactive power imbalance of the new energy substation according to the reactive power reference value and the reactive power actual value of the new energy substation;

[0053] S40: Determine the imbalance degree of reactive power of the new energy substation based on the evaluation system.

[0054] In S10, the reactive power reference value of the new energy substation is the reactive power that is expected to be achieved after the new energy substation participates in voltage control based on internal evaluation.

[0055] In S20, the actual value of the reactive power of the new energy substation is the reactive power actually measured after the new energy substation participates in voltage control.

[0056] In S30, when the new energy substation participates in voltage control, due to differences in control strategy, electrical parameters, and response performance of each new energy substation, there will be a large deviation between the actual reactive power value and the reactive power reference value of each new energy substation during voltage control. According to the deviation value between the actual reactive power value of the new energy substation and the reactive power reference value, an evaluation system for reactive power imbalance of the new energy substation is established to quantitatively evaluate reactive power imbalance.

[0057] In S40, if the evaluation system determines that the reactive power of one of the new energy substations is unbalanced, the new energy substation needs secondary adjustment. If the evaluation system determines that the reactive power of the new energy substation as a whole is unbalanced, the new energy substation as a whole needs secondary adjustment.

[0058] The method for judging the degree of reactive power imbalance of a new energy station described in this embodiment obtains a reactive power reference value and an actual reactive power value of the reactive power of a new energy substation, and establishes an evaluation system for reactive power imbalance of the new energy substation according to the reactive power reference value and the actual reactive power value of the new energy substation. The method for judging the degree of reactive power imbalance of a new energy station makes a quantitative evaluation of the degree of reactive power imbalance of the new energy station according to the evaluation system.

[0059] In one embodiment, the new energy substation includes a generator and a reactive power compensator. Figure 3 , the S10 comprises:

[0060] S100, obtaining the initial reactive power value of the generator node and the reactive power compensator node;

[0061] S110, obtaining reactive power changes of the generator node and the reactive power compensator node;

[0062] S120, calculating a reactive power reference value of the generator node according to the reactive power change and the initial reactive power value of the generator node, and calculating a reactive power reference value of the reactive compensator node according to the reactive power change and the initial reactive power value of the reactive compensator node;

[0063] The generator node is the connection point between the generator and the power grid, and the reactive power compensator node is the connection point between the reactive power compensator and the power grid; the power grid is connected to the new energy substation.

[0064] In S100, the generator node and the reactive compensator node can provide reactive power to maintain the voltage of the new energy master station. The initial reactive power value of the generator node is the reactive power output by the generator node before participating in voltage control. The initial reactive power value of the reactive compensator node is the reactive power output by the reactive compensator node before participating in voltage control. The initial reactive power values ​​of the generator node and the reactive compensator node can be directly measured.

[0065] In S120, the reactive power reference values ​​of the generator node and the reactive power compensator node satisfy formula (1):

[0066]

[0067]

[0068] Among them, Q Gi [k] is the initial value of reactive power of the generator node, ΔQ Gi [k] is the reactive power change of the generator node, is the reactive power reference value of the generator node, the subscript G represents the generator node, i=1,…,m, m is the number of the generator nodes in the new energy substation. Sj [k] is the initial value of reactive power of the reactive compensator node, ΔQ sj [k] is the reactive power change of the reactive compensator node, is the reactive power reference value of the reactive compensator node, the subscript S represents the reactive compensator node, j=1,…,n, n is the number of reactive compensator nodes in the new energy substation, and k represents the kth voltage control time interval.

[0069] In one embodiment, the reactive power compensator may also be installed near the new energy master station as a separate reactive power compensator node to provide reactive power support.

[0070] In one embodiment, the new energy station further comprises a new energy master station, which is connected to the power grid. Figure 4 , the S110 includes:

[0071] S111, establishing a reactive power sensitivity matrix of the new energy substation to obtain voltage changes of the generator node and the reactive power compensator node;

[0072] S112, obtaining a voltage change of the new energy master station according to the reactive power sensitivity matrix;

[0073] S113, acquiring voltage changes of the generator node and the reactive power compensator node according to the reactive power sensitivity matrix;

[0074] S114, calculating the reactive power change of the generator node according to the reactive power sensitivity matrix, the voltage change of the new energy master station and the voltage change of the generator node, and calculating the reactive power change of the reactive compensator node according to the reactive power sensitivity matrix, the voltage change of the new energy master station and the voltage change of the reactive compensator node.

[0075] When voltage control is performed, the power grid sends instructions to the new energy master station, and the new energy master station sends instructions to the new energy substation. The generator and the reactive power compensator change the output of reactive power to maintain the voltage stability of the new energy master station.

[0076] In one embodiment, the power grid includes a load node, and S111 includes:

[0077] S1110, establishing an iterative equation according to the reactive power variation of the generator node and the reactive compensator node, the voltage variation of the generator node and the reactive compensator node, the voltage variation of the new energy master station, the voltage variation of the load node and a sensitivity parameter;

[0078] S1111, simplify and transform the iterative equation to obtain the reactive power sensitivity matrix.

[0079] The load node refers to a node where a component is installed in the power grid. In S1110, assuming that the reactive power of the load node remains unchanged when the voltage of the engine and the reactive compensator changes, the iterative equation can be formula (2):

[0080]

[0081] Wherein, the subscript P represents the new energy main station / key node, and the subscript D represents the load node other than the key node. D [k] is the voltage change of the load node during the voltage control process. ΔV P [k] is the voltage change of the new energy master station during the voltage control process. SD For example, B SD It is a sensitivity parameter of the load node voltage to the reactive power of the reactive compensator node.

[0082] In S1111, the parameters related to the load node are eliminated to obtain the reactive power sensitivity matrix, as shown in the following formula (3):

[0083]

[0084] Here, the superscript ~ represents the matrix obtained after simplified calculation.

[0085] In S112, the reactive power sensitivity matrix is ​​calculated to obtain the voltage change of the new energy master station during the voltage control process, as described in the following formula (4):

[0086]

[0087] in and

[0088] In one embodiment, the S113 includes:

[0089] S1130, obtaining initial voltage values ​​of the generator node and the reactive power compensator node;

[0090] S1131, establishing a voltage optimization power flow model according to the reactive power sensitivity matrix;

[0091] S1132, acquiring voltage reference values ​​of the generator node and the reactive power compensator node according to the voltage optimization power flow model;

[0092] S1133, calculating the voltage change of the generator node according to the initial voltage value of the generator node and the preset voltage reference value of the generator node, and calculating the voltage change of the reactive compensator node according to the initial voltage value of the reactive compensator node and the preset voltage reference value of the reactive compensator node.

[0093] In S1130, the voltage initial value of the generator node is the voltage output by the generator node before participating in voltage control. The voltage initial value of the reactive power compensator node is the voltage output by the reactive power compensator node before participating in voltage control. The voltage initial values ​​of the generator node and the reactive power compensator node can be directly measured and obtained.

[0094] In S1131, the optimized power flow model is obtained based on the formula (4) as shown in the following formula (5):

[0095]

[0096] in, is the voltage reference value of the generator node, is the voltage reference value of the reactive power compensator, is the voltage command value of the generator node, is the voltage command value of the reactive power compensator.

[0097] The voltage command value of the generator node is the voltage that is expected to be achieved after the generator node in the new energy substation participates in voltage control, which is calculated by the dispatching end of the power grid through optimizing power flow. The voltage command value of the reactive power compensator node is the voltage that is expected to be achieved after the reactive power compensator node in the new energy substation participates in voltage control, which is calculated by the dispatching end of the power grid through optimizing power flow. The voltage command value of the generator node and the voltage command value of the reactive power compensator node can be given by the power grid.

[0098] In the S1132, the voltage reference value of the generator node is calculated by the above formula (5). The voltage reference value of the reactive power compensator node is calculated by the above formula (5).

[0099] In S1133, the voltage variation of the generator node and the reactive power compensator node satisfies formula (6):

[0100]

[0101]

[0102] Among them, V Gi [k] is the initial value of the voltage at the generator node, ΔV Gi [k] is the voltage change of the generator node. Sj [k] is the initial voltage value of the reactive compensator node, ΔV Sj [k] is the voltage change at the reactive compensator node.

[0103] In S114, the voltage change ΔV of the generator node and the reactive power compensator node is calculated. Gi [k] and ΔV Sj [k] and the voltage change ΔV of the new energy master station during the voltage control process P [k] is substituted into the reactive power sensitivity matrix (Formula (3)) to calculate the reactive power change ΔQ of the generator node and the reactive compensator node Gi [k] and ΔQ sj [k].

[0104] In one embodiment, the evaluation system includes quantitative evaluation indicators of each of the new energy substations and quantitative evaluation indicators of the new energy substation as a whole, and S30 includes:

[0105] S300, calculating a quantitative evaluation index of each of the new energy substations according to a reactive power reference value and an actual reactive power value of the new energy substation;

[0106] S310: Calculate the overall quantitative evaluation index of the new energy substation according to the reactive power reference value and the reactive power actual value of the new energy substation.

[0107] In S300, in one embodiment, the quantitative evaluation index of each of the new energy substations includes: reactive power deviation, reactive power deviation ratio and reactive power deviation capacity ratio. The reactive power deviation is shown in the following formula (7):

[0108]

[0109]

[0110]

[0111] Among them, Q dev,f,k is the reactive power deviation of the new energy substation (wind farm) f after voltage adjustment at time k; is the actual value of reactive power after voltage adjustment of the generator node i in the new energy substation f at time k; is the actual value of reactive power after voltage adjustment of the reactive compensator node j in the new energy substation f at time k; is the reactive power reference value of the generator node i in the new energy substation f at time k; is the reactive power reference value of the reactive compensator node j in the new energy substation f at time k. The reactive power deviation can represent the absolute size of the reactive power deviation.

[0112] The reactive power deviation ratio is shown in the following formula (8):

[0113]

[0114] Among them, Q rat-ref,f,K is the reactive power deviation ratio of the new energy substation f at time k. The reactive power deviation ratio can represent the relative size of the reactive power deviation and the reactive power reference value.

[0115] The reactive power deviation capacity ratio is shown in the following formula (9):

[0116]

[0117] Among them, Q f,rated is the reactive power rating of the new energy substation f. The reactive power rating may be given by the new energy substation f. The reactive power deviation capacity ratio may characterize the relative size of the reactive power deviation and the maximum reactive power that can be output.

[0118] In S300, in one embodiment, the quantitative evaluation index of the new energy substation as a whole includes: the overall reactive power deviation ratio and the maximum reactive power deviation ratio. The overall reactive power deviation ratio is shown in the following formula (10):

[0119]

[0120] Wherein, d is a positive integer. The overall reactive power deviation ratio can represent the relative size of the overall reactive power deviation of the new energy substation and the overall reactive power reference value of the new energy substation.

[0121] The maximum reactive power deviation is shown in the following formula (11):

[0122]

[0123] Among them, Q maxdev,k The maximum reactive power deviation ratio is the ratio of the maximum reactive power deviation of the new energy substation as a whole to the total reactive power deviation at time k. The maximum reactive power deviation ratio can represent the ratio of the maximum reactive power deviation of the new energy substation as a whole to the total reactive power deviation, and the main source of the reactive unbalanced power of the new energy substation as a whole can be obtained based on the new energy substation as a whole.

[0124] In one embodiment, the S40 includes:

[0125] S400, when the reactive power deviation ratio is greater than a first preset value, and the reactive power deviation capacity ratio is greater than a second preset value, the reactive power of the new energy substation is unbalanced; the new energy substation requires secondary adjustment.

[0126] S410: When the overall reactive power deviation ratio is greater than a third preset value, and the maximum reactive power deviation ratio is greater than a fourth preset value, the overall reactive power of the new energy substation is unbalanced, and the new energy substation needs secondary adjustment.

[0127] In S400, the first preset value may be 50%, and the second preset value may be 30%.

[0128] In S410, the third preset value may be 30%, and the fourth preset value may be 30%.

[0129] In one embodiment, the initial state of the new energy station is as follows: Figure 5As shown, the reactive power reference values ​​of the new energy substation 1 and the new energy substation 2 are obtained by calculation. Each of the new energy substations in the new energy station responds to the voltage control instruction of the new energy master station to adjust the reactive power of the new energy substation. Due to the differences in control strategy, electrical parameters, and response performance of each of the new energy substations, the actual reactive power value of each of the new energy substations cannot accurately reach the reactive power reference value.

[0130] Assuming that after voltage control, the actual values ​​of reactive power of the new energy substation 1 and the new energy substation 2 are 34.25Mvar and 23.61Mva respectively, the various indicators in the evaluation system can be calculated as follows: Figure 6 At this time, although the maximum reactive power deviation accounts for more than 30%, the reactive power deviation ratios of the new energy substations are all less than 50%, and the reactive deviation capacity ratio is less than 30%, and the overall reactive deviation ratio is less than 30%, so there is no reactive power imbalance.

[0131] Assuming that after voltage control, the actual values ​​of reactive power of the new energy substation 1 and the new energy substation 2 are 53.83Mvar and 10.02Mvar respectively, the various indicators in the evaluation system can be calculated as follows: Figure 7 At this time, the reactive power deviation of each of the new energy substations is relatively large, and the overall reactive power deviation ratio is greater than 30% and the maximum reactive power deviation accounts for more than 30%, indicating that there is a large deviation between the actual reactive power value of each of the new energy substations and its reactive power reference value, and the maximum deviation of the new energy substation accounts for a large proportion of the overall deviation, and it is determined that the new energy substation has an overall reactive power imbalance and needs secondary adjustment.

[0132] It should be understood that although Figure 2-4 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 2-4 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0133] In one embodiment, a device for judging the degree of reactive power imbalance of a new energy station is provided, comprising: a data acquisition module, a data processing module and a judgment module, wherein: the data acquisition module is used to obtain the actual value of reactive power of the new energy substation. The data processing module is used to obtain the reactive power reference value of the new energy substation, and establish an evaluation system for reactive power imbalance of the new energy substation according to the reactive power reference value and the actual value of reactive power of the new energy substation. The judgment module is used to determine the degree of reactive power imbalance of the new energy substation based on the evaluation system.

[0134] For the specific definition of the device for judging the degree of reactive power imbalance of the new energy station, please refer to the definition of the method for judging the degree of reactive power imbalance of the new energy station mentioned above, which will not be repeated here. Each module in the device for judging the degree of reactive power imbalance of the new energy station mentioned above can be implemented in whole or in part by software, hardware and a combination thereof. The above modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0135] In one embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps of the method described in any one of the above embodiments when executing the computer program.

[0136] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method described in any of the above embodiments are implemented.

[0137] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and 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-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. 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. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0138] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0139] The above-described embodiments only express several implementation methods of the present application, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present application, which all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the attached claims.

Claims

1. A method for determining the degree of reactive power imbalance in a new energy station, characterized in that: The new energy station includes a plurality of new energy substations, and the method includes: S10, obtaining a reactive power reference value of the new energy substation; S20, obtaining the actual value of reactive power of the new energy substation; S30, establishing an evaluation system for reactive power imbalance of the new energy substation according to the reactive power reference value and the actual reactive power value of the new energy substation; the evaluation system includes quantitative evaluation indicators of each of the new energy substations and quantitative evaluation indicators of the new energy substation as a whole; the quantitative evaluation indicators of each of the new energy substations include reactive power deviation, reactive power deviation ratio and reactive power deviation capacity ratio; the quantitative evaluation indicators of the new energy substation as a whole include overall reactive power deviation ratio and maximum reactive power deviation ratio; S40, determining the imbalance degree of reactive power of the new energy substation based on the evaluation system; Wherein, the S40 includes: S400, when the reactive power deviation ratio is greater than the first preset value, and the reactive power deviation capacity ratio is greater than the second preset value, the reactive power of the new energy substation is unbalanced; S410, when the overall reactive power deviation ratio is greater than the third preset value, and the maximum reactive power deviation ratio is greater than the fourth preset value, the overall reactive power of the new energy substation is unbalanced; Wherein, the new energy substation includes a generator and a reactive compensator, and the S10 includes: S100, obtaining the reactive power initial value of the generator node and the reactive compensator node; S110, obtaining the reactive power change of the generator node and the reactive compensator node; S120, calculating the reactive power reference value of the generator node according to the reactive power change and the reactive power initial value of the generator node, and calculating the reactive power reference value of the reactive compensator node according to the reactive power change and the reactive power initial value of the reactive compensator node; the generator node is the connection point between the generator and the power grid, and the reactive compensator node is the connection point between the reactive compensator and the power grid; the power grid is connected to the new energy substation; Wherein, the new energy site also includes a new energy main station, and the new energy main station is connected to the power grid, and the S110 includes: S111, establishing a reactive power sensitivity matrix of the new energy substation; S112, obtaining the voltage change of the new energy main station according to the reactive power sensitivity matrix; S113, obtaining the voltage change of the generator node and the reactive compensator node according to the reactive power sensitivity matrix; S114, calculating the reactive power change of the generator node according to the reactive power sensitivity matrix, the voltage change of the new energy main station and the voltage change of the generator node, and calculating the reactive power change of the reactive compensator node according to the reactive power sensitivity matrix, the voltage change of the new energy main station and the voltage change of the reactive compensator node; Wherein, the power grid includes a load node, and the S111 includes: S1110, establishing an iterative equation according to the reactive power change of the generator node and the reactive compensator node, the voltage change of the generator node and the reactive compensator node, the voltage change of the new energy master station, the voltage change of the load node and the sensitivity parameter; S1111, simplifying and transforming the iterative equation to obtain the reactive power sensitivity matrix; Among them, the S113 includes: S1130, obtaining the initial voltage values ​​of the generator node and the reactive compensator node; S1131, establishing a voltage optimization power flow model according to the reactive power sensitivity matrix; S1132, obtaining the voltage reference values ​​of the generator node and the reactive compensator node according to the voltage optimization power flow model; S1133, calculating the voltage change of the generator node according to the initial voltage value of the generator node and the voltage reference value of the generator node, and calculating the voltage change of the reactive compensator node according to the initial voltage value of the reactive compensator node and the voltage reference value of the reactive compensator node.

2. The method for determining the degree of reactive power imbalance of a new energy station according to claim 1, characterized in that: The S30 includes: S300, calculating a quantitative evaluation index of each of the new energy substations according to a reactive power reference value and an actual reactive power value of the new energy substation; S310: Calculate the overall quantitative evaluation index of the new energy substation according to the reactive power reference value and the reactive power actual value of the new energy substation.

3. The method for determining the degree of reactive power imbalance of a new energy station according to claim 1, characterized in that: The S40 includes: If the reactive power of one of the new energy substations is determined to be unbalanced based on the evaluation system, the new energy substation needs secondary adjustment; If it is determined based on the evaluation system that the reactive power of the new energy substation as a whole is unbalanced, the new energy substation as a whole needs a secondary adjustment.

4. The method for determining the degree of reactive power imbalance of a new energy station according to claim 1, characterized in that: The reactive power deviation ratio can be expressed as: in, For the moment The new energy substation Reactive power deviation ratio; For the new energy substation exist The reactive power deviation after voltage adjustment at each moment; For the new energy substation The generator node in exist Reactive power reference value at the moment; For the new energy substation The reactive compensator node in exist Reactive power reference value at the moment; subscript represents the generator node, , is the number of the generator nodes in the new energy substation; represents the reactive compensator node, , is the number of the reactive power compensator nodes in the new energy substation.

5. The method for determining the degree of reactive power imbalance of a new energy station according to claim 1, characterized in that: The reactive power deviation capacity ratio can be expressed as: in, For the moment The new energy substation Reactive power deviation capacity ratio; For the new energy substation Reactive power rating of For the new energy substation exist The reactive power deviation after voltage adjustment at that moment.

6. A device for determining the degree of reactive power imbalance in a new energy station, characterized in that: The new energy station includes a plurality of new energy substations, and the judging device includes: A data acquisition module, used to obtain the actual value of reactive power of the new energy substation; A data processing module, used for obtaining the reactive power reference value of the new energy substation, and establishing an evaluation system for reactive power imbalance of the new energy substation according to the reactive power reference value and the actual reactive power value of the new energy substation; the evaluation system includes quantitative evaluation indicators of each of the new energy substations and quantitative evaluation indicators of the new energy substation as a whole; the quantitative evaluation indicators of each of the new energy substations include reactive power deviation, reactive power deviation ratio and reactive power deviation capacity ratio; the quantitative evaluation indicators of the new energy substation as a whole include overall reactive power deviation ratio and maximum reactive power deviation ratio; A judgment module, used for judging the imbalance degree of reactive power of the new energy substation based on the evaluation system; Wherein, the judgment module is specifically used for: when the reactive power deviation ratio is greater than the first preset value, and the reactive power deviation capacity ratio is greater than the second preset value, the reactive power of the new energy substation is unbalanced; when the overall reactive power deviation ratio is greater than the third preset value, and the maximum reactive power deviation ratio is greater than the fourth preset value, the overall reactive power of the new energy substation is unbalanced; Wherein, the new energy substation includes a generator and a reactive compensator, and the data processing module is specifically used to: obtain the initial reactive power value of the generator node and the reactive compensator node; obtain the reactive power change of the generator node and the reactive compensator node; calculate the reactive power reference value of the generator node according to the reactive power change and the initial reactive power value of the generator node, and calculate the reactive power reference value of the reactive compensator node according to the reactive power change and the initial reactive power value of the reactive compensator node; the generator node is the connection point between the generator and the power grid, and the reactive compensator node is the connection point between the reactive compensator and the power grid; the power grid is connected to the new energy substation; Among them, the new energy site also includes a new energy main station, and the new energy main station is connected to the power grid. The data processing module is specifically used to: establish a reactive power sensitivity matrix of the new energy substation; obtain the voltage change of the new energy main station according to the reactive power sensitivity matrix; obtain the voltage change of the generator node and the reactive compensator node according to the reactive power sensitivity matrix; calculate the reactive power change of the generator node according to the reactive power sensitivity matrix, the voltage change of the new energy main station and the voltage change of the generator node, and calculate the reactive power change of the reactive compensator node according to the reactive power sensitivity matrix, the voltage change of the new energy main station and the voltage change of the reactive compensator node; Wherein, the power grid includes a load node, and the data processing module is specifically used to: establish an iterative equation according to the reactive power change of the generator node and the reactive compensator node, the voltage change of the generator node and the reactive compensator node, the voltage change of the new energy master station, the voltage change of the load node and the sensitivity parameter; simplify and transform the iterative equation to obtain the reactive power sensitivity matrix; Among them, the data processing module is specifically used to: obtain the initial voltage values ​​of the generator node and the reactive compensator node; establish a voltage optimization power flow model according to the reactive power sensitivity matrix; obtain the voltage reference values ​​of the generator node and the reactive compensator node according to the voltage optimization power flow model; calculate the voltage change of the generator node according to the initial voltage value of the generator node and the voltage reference value of the generator node, and calculate the voltage change of the reactive compensator node according to the initial voltage value of the reactive compensator node and the voltage reference value of the reactive compensator node.

7. The device for determining the degree of reactive power imbalance of a new energy station according to claim 6, characterized in that: The data processing module is specifically used for: Calculating a quantitative evaluation index of each of the new energy substations according to a reactive power reference value and an actual reactive power value of the new energy substation; The overall quantitative evaluation index of the new energy substation is calculated according to the reactive power reference value and the reactive power actual value of the new energy substation.

8. The device for determining the degree of reactive power imbalance of a new energy station according to claim 6, characterized in that: The judgment module is specifically used for: If the reactive power of one of the new energy substations is determined to be unbalanced based on the evaluation system, the new energy substation needs secondary adjustment; If it is determined based on the evaluation system that the reactive power of the new energy substation as a whole is unbalanced, the new energy substation as a whole needs a secondary adjustment.

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 5 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 5 are implemented.

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