Substation SVG reactive dead zone hedging allocation strategy and device

Abstract

The present application relates to the technical field of power system, disclose a kind of station SVG reactive dead zone hedging distribution strategy and device.The station SVG reactive dead zone hedging distribution strategy of the present application includes the following steps: obtaining application station information;Obtain total reactive demand Q req ;Based on total reactive demand Q req , determine minimum constraint target T min Calculation method;Iterative solution minimum constraint target T min And store corresponding calculation result;Based on the total reactive demand and the minimum constraint target T min , determine the reactive power distribution strategy corresponding to each available SVG, obtain reactive power instruction matrix.The station SVG reactive dead zone hedging distribution strategy of the present application can realize the accurate distribution of reactive power instruction under different SVG rated capacity and different SVG reactive dead zone, improve the precision of station reactive control;It can be realized that each SVG reactive output load is minimum under the premise of meeting total reactive demand, corresponding SVG device loss is minimum, and the operating life of SVG device is improved.

Description

TECHNICAL FIELD

[0001] The embodiment of the application relates to the technical field of power systems, in particular to a station SVG reactive power dead zone hedging distribution strategy and device. BACKGROUND

[0002] As a kind of reactive power compensation equipment, static var generator (SVG) is widely used in new power system with high proportion of new energy generation and high proportion of power electronic devices (referred to as "double high" system) due to its fast reactive current regulation speed, high control accuracy and dynamic continuous compensation, especially high-voltage large-capacity H-bridge cascaded SVG.

[0003] Due to inconsistent power module parameters, DC side capacitor voltage balance control requirements, modulation algorithm and other reasons, in order to maintain the safe and stable operation of SVG equipment, SVG equipment has a reactive power dead zone, that is, the reactive power instruction is less than the SVG reactive power dead zone, and the SVG actually outputs according to the reactive power dead zone. The related standards such as NB / T 42043-2014 and DL / T 1215.1-2020 have relevant provisions for SVG reactive power dead zone. The actual engineering single SVG reactive power dead zone is generally 5%~10% of the rated capacity of SVG.

[0004] Under the background of "double high" system, multiple sets of SVG equipment are installed in new energy station, and the output characteristics of photovoltaic and wind power change naturally over time. The demand for SVG reactive power is different and random at different time periods, and the SVG output in the reactive power dead zone is a common working condition, but limited by the characteristics of the equipment, the SVG cannot do it, and can only output according to the minimum dead zone. Especially when multiple SVG dead zones are superimposed, it will cause the mismatch between the reactive power demand of the station and the actual output of the equipment, cause the system voltage to be unable to adjust in place, cause economic loss to the user being examined, and increase the risk of power system instability.

[0005] A Chinese patent with publication number CN116896091A discloses a reactive power distribution method and device for multiple SVGs in a new energy station, which determines the distribution boundary and distribution strategy corresponding to the reactive power instruction through the reactive power instruction and the dead zone boundary set. For example, the application case: the reactive power demand is 2.5Mvar, 4 SVGs are distributed, and the SVG dead zone is 1Mvar, the distribution result is [1.5Mvar, 1Mvar, 1Mvar, -1Mvar], it can be seen that the excess 0.5Mvar is borne by one of the SVGs, and the more optimal [1.167Mvar, 1.167Mvar, 1.167Mvar, -1Mvar] distribution strategy cannot be achieved, and the reactive power distribution is not balanced; and the distribution method is not suitable for the case where the rated capacity of SVG is different and the SVG dead zone is different.

[0006] When more than one SVG is available in the same station, some SVGs can generate inductive reactive power and some SVGs can generate capacitive reactive power, that is, SVG reactive power dead zone offset, to realize accurate tracking of the overall reactive power small capacity command demand of the station. Therefore, an SVG reactive power dead zone offset distribution strategy is needed to ensure that the reactive power command distributed to each SVG is outside the dead zone of each SVG and is balanced, while the overall reactive power command of the station can accurately follow the actual demand. SUMMARY

[0007] The purpose of the present application is to provide a station SVG reactive power dead zone offset distribution strategy and device to solve the problems in the background art.

[0008] The embodiment of the present application provides a station SVG reactive power dead zone offset distribution strategy, comprising the following steps:

[0009] S1 obtains application station information;

[0010] S2 obtains total reactive power demand Q req ;

[0011] S3 determines the minimum constraint target T min calculation method based on the total reactive power demand Q req ;

[0012] S4 iteratively solves the minimum constraint target T min and stores the corresponding calculation results;

[0013] S5 determines the reactive power distribution strategy corresponding to each available SVG based on the total reactive power demand and the minimum constraint target T min , and obtains a reactive power command matrix.

[0014] Based on the above scheme, the station SVG reactive power dead zone offset distribution strategy of the present application constructs the calculation method of the minimum constraint target in iteration according to the total reactive power demand, combines the available SVGs, SVG reactive power dead zones and other information of the application station, iteratively calculates the minimum constraint target and stores the corresponding optimal calculation results, determines the SVG reactive power distribution strategy according to the optimal calculation results and calculates the reactive power command of each SVG, can realize accurate distribution of the reactive power command under different SVG rated capacities and different SVG reactive power dead zones, improve the station reactive power control precision; can realize the minimum SVG reactive power output load and improve the SVG equipment operating life.

[0015] In a feasible scheme, in step S1, the application station information includes:

[0016] Obtain the SVG number matrix S A of the station, S A =[1, 2, …, N], N represents the total number of SVGs in the station;

[0017] Obtaining SVG rated capacity matrix Q n , Q n = [Q n1 , Q n2 , …, Q nN ], Q ni represents the rated capacity of the SVG numbered i, and also represents the i-th element in the matrix Q n ;

[0018] Obtaining SVG reactive dead zone matrix Q min , Q min = [Q min1 , Q min2 , …, Q minN ], Q mini represents the reactive dead zone of the SVG numbered i, and also represents the i-th element in the matrix Q min ;

[0019] Obtaining the site available SVG numbered matrix A, A = [d1, d2, …, d n ], n represents the total number of available SVGs;

[0020] Creating the first combination matrix A1 of available SVG numbers, which is used to store the available SVG numbers opposite in sign to the final output instruction and Q req , A1 = [e1, e2, …, e m ], m represents the number of available SVGs opposite in sign to Q req ;

[0021] Creating the second combination matrix A2 of available SVG numbers, which is used to store the available SVG numbers same in sign to the final output instruction and Q req , A2 = [f1, f2, …, f n-m ], n-m represents the number of available SVGs same in sign to Q req .

[0022] In a feasible scheme, in step S1, the obtaining application site information further includes:

[0023] Obtaining the rated capacity cumulative sum of the SVG numbers corresponding to the matrix A nA : ;

[0024] Obtaining the rated capacity cumulative sum of the SVG numbers corresponding to the matrix A1 : ;

[0025] Obtaining the rated capacity cumulative sum of the SVG numbers corresponding to the matrix A2 : ;

[0026] get the reactive dead-zone cumulative sum Q corresponding to the SVG number of matrix A M : ;

[0027] get the reactive dead-zone cumulative sum Q corresponding to the SVG number of matrix A1 M1 : ;

[0028] get the reactive dead-zone cumulative sum Q corresponding to the SVG number of matrix A2 M2 : ;

[0029] wherein, A i represents the i-th element d i of matrix A 1j A j represents the j-th element e 2k of matrix A1 k .

[0030] In a feasible scheme, in step S3, the minimum constraint target T req is determined based on the total reactive demand Q min The calculation method comprises:

[0031] If Q req ≥ 0, then T min = Q req + Q M1 - Q M2 ;

[0032] If Q req < 0, then T min = -Q req + Q M1 - Q M2 .

[0033] In a feasible scheme, in step S4, the minimum constraint target T min is solved iteratively and the corresponding calculation result is stored, comprising:

[0034] initially assign T min = T min0 = Q nA ;

[0035] Take any one or more values in matrix A to form a first combined matrix A1, and iterate in turn, as follows:

[0036] 1st iteration;

[0037] A1 = [1], then Q M1 = Q min1, A2 = [2, 3,..., n], Q M2 = Q M - Q M1 , T min is calculated based on the calculation method determined in step S3;

[0038] If |T min | < |T min0 |, or |T min | = |T min0 | and T min > 0 and T min0 < 0, then T min0 = T min , and the corresponding A1, A2, Q M1 and Q M2 are stored;

[0039] If |T min | > |T min0 |, T min0 is not updated, and the iteration calculation is continued;

[0040] The second iteration:

[0041] A1 = [2], Q M1 = Q min2 , A2 = [1, 3,..., n], Q M2 = Q M - Q M1 , T min is calculated based on the calculation method determined in step S3;

[0042] If |T min | < |T min0 |, or |T min | = |T min0 | and T min > 0 and T min0 < 0, then T min0 = T min , and the corresponding A1, A2, Q M1 and Q M2 are stored;

[0043] If |T min | > |T min0 |, T min0 is not updated, and the iteration calculation is continued;

[0044] ...

[0045] The (2 n -1)th iteration:

[0046] A1 = [1, 2,..., n], Q M1 = QM , A2 = [], Q M2 = Q M - Q M1 = 0, T min is calculated based on the calculation method determined in step S3.

[0047] If |T min | < |T min0 |, or |T min | = |T min0 | and T min > 0 and T min0 < 0, then T min0 = T min , and the corresponding A1, A2, Q M1 and Q M2 are stored.

[0048] If |T min | > |T min0 |, then T min0 is not updated.

[0049] The iteration ends, and the minimum constraint target T min and its corresponding A1, A2, Q M1 and Q M2 are stored.

[0050] In one possible solution, in step S5, the reactive power allocation strategy corresponding to each available SVG is determined based on the total reactive power demand and the minimum constraint target T min , including:

[0051] If Q req ≥ 0 and T min ≥ 0, then the reactive power command of each available SVG is allocated as follows: , .

[0052] If Q req ≥ 0 and T min < 0, then the reactive power command of each available SVG is allocated as follows: , .

[0053] If Q req < 0 and T min ≥ 0, then the reactive power command of each available SVG is allocated as follows: , .

[0054] If Q req < 0 and T min < 0, then the reactive power command of each available SVG is allocated as follows: , .

[0055] get available SVG reactive power instruction matrix Q C , Q C = [Q CA1 , Q CA2 , …, Q CAn ];

[0056] wherein, denotes the SVG reactive power instruction numbered A i , Q denotes the SVG reactive power instruction numbered A 1j , Q denotes the SVG reactive power instruction numbered A 2k .

[0057] The embodiment of the present application also provides a site SVG reactive power dead zone hedging distribution device, comprising:

[0058] an instruction generation module for generating total reactive power demand;

[0059] an iterative solution module for iteratively solving a minimum constraint target T min and corresponding A1, A2, Q M1 and Q M2 ;

[0060] a reactive power instruction distribution calculation module for calculating the reactive power instruction distributed to each available SVG;

[0061] a reactive power instruction issuing module for issuing the reactive power instruction to each available SVG.

[0062] In a feasible scheme, the total reactive power demand is derived from an external system or an internal device.

[0063] The site SVG reactive power dead zone hedging distribution strategy and device provided by the present application, according to the calculation method of the minimum constraint target constructed according to the total reactive power demand, iteratively calculates the minimum constraint target and stores the corresponding optimal calculation result, determines the SVG reactive power distribution strategy according to the optimal calculation result and calculates each SVG reactive power instruction. The present application optimizes the minimum constraint target through a software control algorithm, respectively calculates the SVG reactive power instruction and avoids the situation that the reactive power instruction issued to the SVG is less than each SVG reactive dead zone, can realize accurate distribution of the reactive power instruction under different SVG rated capacities and different SVG reactive dead zones, achieves the purpose of accurately issuing the SVG reactive power instruction, improves the site reactive power control precision; can realize minimum SVG reactive power output load and minimum corresponding SVG device loss under the premise of meeting the total reactive power demand, improves the SVG device operation life; when there is SVG device maintenance in the site, i.e. S A≠A, and when the number of remaining available SVGs is greater than 1, the allocation strategy of this invention can achieve precise allocation of the remaining available SVGs to offset the reactive dead zone. Attached Figure Description

[0064] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0065] Figure 1 This is a flowchart illustrating the reactive power dead zone offsetting allocation strategy of the SVG in Embodiment 1 of the present invention.

[0066] Figure 2 As in Embodiment 1 of the present invention Figure 1 The first enlarged view of the part;

[0067] Figure 3 As in Embodiment 1 of the present invention Figure 1 The second enlarged view in the image;

[0068] Figure 4 As in Embodiment 1 of the present invention Figure 1 The third enlarged view in the image;

[0069] Figure 5 This is a schematic diagram of the station SVG reactive dead zone offset distribution device in Embodiment 2 of the present invention. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0071] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0072] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected, or it can be communicatively connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above-mentioned terms in the present application can be understood according to the specific circumstances.

[0073] The technical solutions of the present application will be described in detail below with specific examples. The following specific examples can be combined with each other, and the same or similar concepts or processes can not be described in some examples.

[0074] Example one: Figure 1 The flowchart of the station SVG reactive dead zone hedging allocation strategy in the first embodiment of the present application is shown in the figure, Figure 2 The first partial enlarged view in the Figure 1 The second partial enlarged view in the Figure 3 The third partial enlarged view in the Figure 1 The third partial enlarged view in the Figure 4 The third partial enlarged view in the Figure 1 The third partial enlarged view in the

[0075] As shown in Figures 1 to 4 , the station SVG reactive dead zone hedging allocation strategy of the present embodiment comprises the following steps:

[0076] S1 obtains the application station information.

[0077] S2 obtains the total reactive power demand Q req .

[0078] S3 determines the minimum constraint target T min based on the obtained total reactive power demand Q req .

[0079] S4 iteratively solves the minimum constraint target T min and stores the corresponding calculation results.

[0080] S5 determines the reactive power allocation strategy corresponding to each available SVG based on the total reactive power demand and the solved minimum constraint target T min , and obtains the reactive power instruction matrix.

[0081] It is easy to see from the above that the reactive power dead zone offsetting allocation strategy of the power station SVG in this embodiment constructs a calculation method for the minimum constraint target during iteration based on the total reactive power demand. Combining the available SVGs and SVG reactive power dead zones of the application power station, iteratively calculates the minimum constraint target and stores the corresponding optimal calculation results. Based on the optimal calculation results, the SVG reactive power allocation strategy is determined and the reactive power commands of each SVG are calculated. This can achieve accurate allocation of reactive power commands under different SVG rated capacities and different SVG reactive power dead zones, improve the reactive power control accuracy of the power station, and minimize the reactive power output load of each SVG, thereby extending the service life of the SVG equipment.

[0082] Optionally, in this embodiment, the reactive power dead zone offsetting allocation strategy for the SVG of the power station includes, in step S1, obtaining the application power station information, including:

[0083] Obtain the matrix S of all SVG numbers within the site. A All SVGs within the facility are numbered from 1 to N, resulting in the SVG numbering matrix S for all SVGs in the facility. A S A = [1, 2, ..., N], where N represents the total number of SVGs equipped at the station, which is a positive integer greater than or equal to 2, and S Ai Representation matrix S A The i-th element.

[0084] Get the rated capacity matrix Q of all SVGs n Q n =[Q n1 Q n2 Q nN ], Q ni This indicates the rated capacity corresponding to SVG numbered i, of course Q ni Also represents matrix Q n The i-th element.

[0085] Get the reactive dead zone matrix Q of all SVGs min Q min =[Q min1 Q min2 Q minN ], Q mini This indicates that the SVG with ID i corresponds to the reactive power dead zone, Q. mini Also represents matrix Q min The i-th element.

[0086] Obtain the available SVG number matrix A. The available SVGs are automatically identified and stored in matrix A by the reactive power dead zone offsetting device according to the operating status of each SVG. A = [d1, d2, ..., d... n ], where n represents the total number of available SVGs within the site, A idenotes the i-th element d i .

[0087] A first combination matrix A1 of available SVG numbers is created, and the first combination matrix A1 is used to store the final output instruction and Q req , and A1 = [e1, e2, …, em] denotes the available SVG numbers whose numerical signs are opposite to Q m , and m denotes the number of available SVGs whose numerical signs are opposite to Q req (total reactive power demand), and A 1j denotes the j-th element e j .

[0088] A second combination matrix A2 of available SVG numbers is created, and the second combination matrix A2 is used to store the final output instruction and Q req (total reactive power demand), and A2 = [f1, f2, …, fn-m] denotes the available SVG numbers whose numerical signs are the same as Q n-m (total reactive power demand), and n-m denotes the number of available SVGs whose numerical signs are the same as Q req (total reactive power demand), and A 2k denotes the k-th element f k .

[0089] As can be seen from the above, the elements in the first combination matrix A1 and the elements in the second combination matrix A2 are mutually exclusive, that is, A = A1 + A2.

[0090] Further, in the station SVG reactive dead zone hedging allocation strategy in the embodiment, the obtaining application station information in step S1 further includes:

[0091] After calculation, the rated capacity cumulative sum Q nA of the SVG numbers corresponding to the matrix A is obtained: ;

[0092] After calculation, the rated capacity cumulative sum Q of the SVG numbers corresponding to the matrix A1 is obtained: ;

[0093] After calculation, the rated capacity cumulative sum Q of the SVG numbers corresponding to the matrix A2 is obtained: ;

[0094] After calculation, the reactive dead zone cumulative sum Q M of the SVG numbers corresponding to the matrix A is obtained: ;

[0095] After calculation, the reactive dead zone cumulative sum Q M1 of the SVG numbers corresponding to the matrix A1 is obtained: ;

[0096] After calculation, the cumulative sum of reactive power dead zones Q corresponding to the SVG number in matrix A2 is obtained. M2 : ;

[0097] Among them, A i d represents the i-th element in matrix A i A 1j Represents the j-th element e in matrix A1 j A 2k f represents the k-th element in matrix A2 k .

[0098] Furthermore, since the elements in the first combination matrix A1 are mutually exclusive with the elements in the second combination matrix A2, therefore: Q M =Q M1 +Q M2 .

[0099] Furthermore, in this embodiment, the reactive power dead zone offsetting allocation strategy for the power station SVG, in step S3, is based on the total reactive power demand Q. req Determine the minimum constraint objective T min Calculation methods include:

[0100] If Q req If T ≥ 0, then T min =Q req +Q M1 -Q M2 (1)

[0101] If Q req <0, then T min =-Q req +Q M1 -Q M2 (2)

[0102] Specifically, based on the obtained total reactive power demand Q req The sign of the numerical value determines the minimum constraint objective T during iteration. min The calculation method for Q, if Q req If the value is negative, then T is calculated using formula (2) during iteration. min If Q req If the value is positive or zero, then T is calculated using formula (1) during iteration. min .

[0103] Furthermore, in this embodiment, the reactive power dead zone offsetting allocation strategy for the power station SVG, in step S4, involves iteratively solving for the minimum constraint objective T. min And store the corresponding calculation results, including:

[0104] Initial assignment T min =T min0=Q nA ;

[0105] Take any one or more values ​​from matrix A to create a first combined matrix A1, and you can obtain the corresponding second combined matrices A2 and Q. M1 and Q M2 Then iterate sequentially. Since matrix A has n numbers, a total of (2... n -1) first combination matrix A1, requires (2) n -1) iterations are performed to solve for the minimum constraint objective T. min The specific process is as follows:

[0106] First iteration;

[0107] Take the value 1 from matrix A to create the first combined matrix A1, then A1 = [1], and the corresponding Q M1 =Q min1 ,A2=[2,3,...,n],Q M2 =Q M -Q M1 T is calculated based on the calculation method determined in step S3. min Then, for the obtained T min Perform logical judgments:

[0108] If [|T] is satisfied min |<|T min0 |、or (|T) min |=|T min0 |and T min >0 and T min0 If the logical condition is <0), then update T. min0 That is, T min0 =T min And store the A1, A2, and Q values ​​corresponding to this iteration. M1 and Q M2 ;

[0109] If |T min |>|T min0 If the logical condition is |, then T will not be updated. min0 And continue iterative calculations.

[0110] Second iteration:

[0111] Take the value 2 from matrix A to create a new first combined matrix A1, then A1 = [2], and the corresponding Q M1 =Q min2 ,A2=[1,3,...,n],Q M2 =Q M -Q M1 T is calculated based on the calculation method determined in step S3.min Then, the obtained T min is subjected to logical judgment:

[0112] If the logical condition of [|T min |<|T min0 |], or (|T min |=|T min0 | and T min >0 and T min0 <0)] is met, T min0 is updated, i.e., T min0 =T min , and the A1, A2, Q M1 and Q M2 corresponding to this iteration are stored.

[0113] If the logical condition of |T min |>|T min0 | is met, T min0 is not updated, and the iteration calculation is continued.

[0114] …

[0115] The (2 n -1)th iteration:

[0116] All the values in the matrix A are taken to create a new first combination matrix A1, i.e., A1=[1, 2, …, n], and the corresponding Q M1 =Q M , A2=[] (at this time, the matrix A2 is empty), Q M2 =Q M -Q M1 =0; T min is calculated based on the calculation method determined in step S3, and then the obtained T min is subjected to logical judgment:

[0117] If the logical condition of [|T min |<|T min0 |], or (|T min |=|T min0 | and T min >0 and T min0 <0)] is met, T min0 is updated, i.e., T min0 =T min , and the A1, A2, Q M1 and Q M2 corresponding to this iteration are stored.

[0118] If the logical condition of |T min |>|T min0 | is met, T min0 is not updated.

[0119] End iteration calculation, T min Update assignment: T min = T min0 , and store the minimum constraint target T min and its corresponding A1, A2, Q M1 and Q M2 .

[0120] Specifically, in this embodiment, first, according to the numerical value of total reactive power demand Q req , it is determined whether formula (1) or formula (2) is used to solve and calculate the minimum constraint target T min .

[0121] Then, the initial assignment of T min is Q nA (the cumulative sum of the rated capacity of the SVG corresponding to the matrix A). In each iteration, any one or more values in the matrix A are taken to create a new first combination matrix A1, and a new A2, Q M1 and Q M2 are obtained accordingly. The value of T min of this iteration is calculated according to the calculation formula of T min , and then logical analysis and judgment are performed on the value of T min : if the absolute value of T min is less than the absolute value of the previously reserved and stored T min0 , or the absolute value of T min is equal to the absolute value of the previously reserved and stored T min0 and the value of T min is greater than 0 and the value of the previously reserved and stored T min0 is less than 0, then the minimum constraint target T min is updated, T min0 is updated to the iteration result T min of this time, and A1, A2, Q M1 and Q M2 corresponding to this iteration are saved; if the absolute value of T min is greater than the absolute value of the previously reserved and stored T min0 , then T min0 is not updated.

[0122] After each iteration, the T min with smaller absolute value is saved, and if the values of T min obtained in different iterations are equal, then the iteration result with positive T min value is saved. There are n available SVGs in the matrix A, and a total of (2 n -1) first combination matrices A1 can be created. After (2 n -1) iterations, the Tmin0 and assign it to the minimum constraint target T min and save the minimum T min0 corresponding A1, A2, Q M1 and Q M2 .

[0123] Further, in the station SVG reactive dead zone hedging allocation strategy in the embodiment, in step S5, the total reactive demand Q req and the minimum constraint target T min solved, determine the corresponding allocation strategy of each available SVG, including:

[0124] If Q req ≥ 0 and T min ≥ 0, the reactive command of each available SVG is allocated as follows:

[0125] (3)

[0126] (4)

[0127] If Q req ≥ 0 and T min < 0, the reactive command of each available SVG is allocated as follows:

[0128] (5)

[0129] (6)

[0130] If Q req < 0 and T min ≥ 0, the reactive command of each available SVG is allocated as follows:

[0131] (7)

[0132] (8)

[0133] If Q req < 0 and T min < 0, the reactive command of each available SVG is allocated as follows:

[0134] (9)

[0135] (10)

[0136] Thus, the SVG reactive command matrix Q C is obtained, Q C = [Q CA1 , Q CA2 , …, Q CAn ].

[0137] wherein, represents the SVG reactive power instruction numbered A i represents the SVG reactive power instruction numbered A 1j represents the SVG reactive power instruction numbered A 2k Q CAn represents the SVG reactive power instruction numbered Ai.

[0138] Specifically, in the embodiment, according to the different positive and negative signs of the total reactive power demand Q req and the minimum constraint target T min value, different distribution methods are adopted to obtain the reactive power instructions of each available SVG, so as to obtain the reactive power instruction matrix Q C of each available SVG, Q C =[Q CA1 , Q CA2 , …, Q CAn ].

[0139] In order to facilitate understanding, the distribution strategy of the application is specifically described by way of example as follows.

[0140] Suppose that there are four SVGs in the station, only three of which are available, and the numbers of the four SVGs are 1, 2, 3 and 4 in turn, the numbers of the three available SVGs are 1, 2 and 4 in turn, and the SVG numbered 3 cannot be unlocked for reactive power distribution due to equipment reasons. The rated capacities of the four SVGs are 30 Mvar, 30 Mvar, 45 Mvar and 45 Mvar in turn, the SVG dead zones are 1 Mvar, 1 Mvar, 2 Mvar and 2 Mvar in turn, the total demand for reactive power is 0.5 Mvar, and the process of distributing the reactive power instructions according to the distribution strategy of the application is as follows:

[0141] Step one, obtain the application station information, including:

[0142] the number matrix S A of all SVGs: S A =[1, 2, 3, 4];

[0143] the SVG rated capacity matrix Q n : Q n =[30, 30, 45, 45];

[0144] the SVG dead zone matrix Q min , Q min =[1, 1, 2, 2];

[0145] the available SVG number matrix A, A=[1, 2, 4]; ​​

[0146] And further get:

[0147] The matrix A corresponds to the rated capacity of SVG number cumulative sum Q nA , Q nA = Q n1 + Q n2 + Q n4 = 30 + 30 + 45 = 105;

[0148] The matrix A corresponds to the SVG number of reactive dead zone cumulative sum Q M , Q M = Q min1 + Q min2 + Q min4 = 1 + 1 + 2 = 4;

[0149] Step two, get the total reactive demand Q req , Q req = 0.5.

[0150] Step three, determine the minimum constraint target T min Calculation method.

[0151] Because Q req = 0.5 ≥ 0, the formula (1) is used to calculate the minimum constraint target T min , that is, T min = Q req + Q M1 - Q M2 .

[0152] Step four, iterative solution of the minimum constraint target T min And store the corresponding calculation results.

[0153] The minimum constraint target initial assignment: T min = T min0 = Q nA = 105.

[0154] The first iteration:

[0155] Take the number 1 in the matrix A to create a matrix A1, then A1 = [1], the corresponding Q M1 = Q min1 = 1, A2 = [2, 4], Q M2 = Q M - Q M1 = 4 - 1 = 3. According to formula (1) to calculate T min , T min = Q req + Q M1 - Q M2 = 0.5 + 1 - 3 = -1.5.

[0156] Then, the obtained T min Perform logical judgments on the value, and use the T obtained in the first iteration. min Value and initial assignment T min0 Comparing them, since |-1.5| < |105|, it satisfies [(|T min |<|T min0 |) or (|T) min |=|T min0 |and T min >0 and T min0 The logical condition is <0), so the T value after this iteration is updated and saved. min Value, T after this iteration min The value was updated from the initial assignment of 105 to -1.5, that is: T min0 =T min = -1.5, and store A1, A2, and Q corresponding to this iteration. M1 And Q M2 That is: A1 = [1], A2 = [2, 4], Q M1 =1, Q M2 =3, then continue iterative calculation.

[0157] Second iteration:

[0158] Take index 2 from matrix A to create a new matrix A1, then A1 = [2], and the corresponding Q M1 =Q min2 =1, A2=[1,4], Q M2 =Q M -Q M1 =4-1=3. The calculation yields: T min =Q req +Q M1 -Q M2 =0.5 + 1 - 3 = -1.5.

[0159] Then, the obtained T min Perform logical judgments on the value, and use the T obtained in the second iteration. min The value is the same as the previously saved T. min The values ​​are compared because [(|T] is not satisfied. min |<|T min0 |) or (|T) min |=|T min0 |and T min >0 and T min0 The logical condition is <0), therefore, after this iteration, T min The value is not updated and remains -1.5 from the first iteration, and the iteration calculation continues.

[0160] 3rd iteration:

[0161] Take the index 4 from matrix A to create a new matrix A1, then A1 = [4], Q M1 =Q min3 =2, A2=[1,2], Q M2 =Q M -Q M1 =4-2=2. The calculation yields: T min =Q req +Q M1 -Q M2 =0.5 + 2 - 2 = 0.5.

[0162] Then, the obtained T min Perform logical judgment on the value, and use the T obtained in the 3rd iteration. min The value is the same as the previously saved T. min The values ​​are compared because |0.5| < |-1.5|, satisfying [(|T min |<|T min0 |) or (|T) min |=|T min0 |and T min >0 and T min0 The logical condition is <0), so the T value after this iteration is updated and saved. min Value, T after this iteration min The value is updated from -1.5 after the first iteration to 0.5, that is: T min0 =T min =0.5, and store A1, A2, and Q corresponding to this iteration. M1 And Q M2 That is: A1 = [4], A2 = [1, 2], Q M1 =2, Q M2 =2, then continue iterative calculation.

[0163] 4th iteration:

[0164] Take the indices 1 and 2 from matrix A to create a new matrix A1, then A1 = [1, 2], Q M1 =Q min1 +Q min2 =1+1=2, A2=[4], Q M2 =Q M -Q M1 =4-2=2. The calculation yields: T min =Q req +Q M1 -Q M2 =0.5 + 2 - 2 = 0.5.

[0165] Then, the obtained T min Perform logical judgment on the value, and use T obtained in the 4th iteration.min value and the previously saved T min value, since the logical condition [(|T min | < |T min0 |) or (|T min | = |T min0 | and T min > 0 and T min0 < 0)] is not satisfied, the T min value is not updated after this iteration, still 0.5 after the third iteration, and the iteration calculation continues.

[0166] Fifth iteration:

[0167] Take the numbers 1 and 3 in matrix A to create a new matrix A1, then A1 = [1, 3], Q M1 = Q min1 + Q min3 = 1 + 2 = 3, A2 = [2], Q M2 = Q M - Q M1 = 4 - 3 = 1. The calculation gives: T min = Q req + Q M1 - Q M2 = 0.5 + 3 - 1 = 2.5.

[0168] Logical judgment is made on the obtained T min value, the T min value obtained in the fifth iteration is compared with the previously saved T min value, since the logical condition [(|T min | < |T min0 |) or (|T min | = |T min0 | and T min > 0 and T min0 < 0)] is not satisfied, the T min value is not updated after this iteration, still 0.5 after the third iteration, and the iteration calculation continues.

[0169] Sixth iteration:

[0170] Take the numbers 2 and 3 in matrix A to create a new matrix A1, then A1 = [2, 3], Q M1 = Q min2 + Q min3 = 1 + 2 = 3, A2 = [1], Q M2 = Q M - Q M1 = 4 - 3 = 1. The calculation gives: T min = Q req + Q M1 - QM2 = 0.5 + 3 - 1 = 2.5.

[0171] The T min value obtained is logically judged, and the T min value obtained in the 6th iteration is compared with the previously saved T min value. Since the logical condition [(|T min | < |T min0 |) or (|T min | = |T min0 | and T min > 0 and T min0 < 0)] is not met, the T min value is not updated after this iteration, and remains 0.5 after the 3rd iteration, and the iteration calculation is continued.

[0172] 7th (2 n -1) iteration:

[0173] Create matrix A1 by taking numbers 1, 2 and 3 in matrix A, then A1 = [1, 2, 3], Q M1 = Q min1 + Q min2 + Q min3 = 1 + 1 + 2 = 4, A2 = [], Q M2 = Q M - Q M1 = 4 - 4 = 0. Calculate: T min = Q req + Q M1 - Q M2 = 0.5 + 4 - 0 = 4.5.

[0174] The T min value obtained is logically judged, and the T min value obtained in the 7th iteration is compared with the previously saved T min value. Since the logical condition [(|T min | < |T min0 |) or (|T min | = |T min0 | and T min > 0 and T min0 < 0)] is not met, the T min value is not updated after this iteration, and remains 0.5 after the 3rd iteration, and the iteration calculation is continued.

[0175] After 7 (2 n -1) iterations, the absolute value of the minimum constraint target T min is solved to be 0.5. Finally, the T min is updated and saved, that is, the minimum constraint target T minFor the value after the 3rd iteration: T min = T min0 = 0.5, corresponding to A1 = [4], A2 = [1, 2], Q M1 = 2, Q M2 = 2.

[0176] Step five, determine the reactive power distribution strategy corresponding to each available SVG, and obtain the reactive power instruction matrix.

[0177] Since in this example, Q req = 0.5 ≥ 0 and T min = 0.5 ≥ 0, the reactive power instructions corresponding to each available SVG are calculated using formula (3) and formula (4): the SVG reactive power instructions contained in matrix A1 are calculated using formula (3), and the SVG reactive power instructions contained in matrix A2 are calculated using formula (4).

[0178] And since A1 = [4] and A2 = [1, 2], it is known that Q nA1 = Q n4 = 45, Q nA2 = Q n1 + Q n2 = 30 + 30 = 60, and the reactive power instructions of each available SVG are as follows:

[0179] SVG1 reactive power instruction:

[0180] Q CA21 = Q C1 = Q min1 + Q n1 / Q nA2 × T min = 1 + 30 / 60 × 0.5 = 1.25

[0181] SVG2 reactive power instruction:

[0182] Q CA22 = Q C2 = Q min2 + Q n2 / Q nA2 × T min = 1 + 30 / 60 × 0.5 = 1.25

[0183] SVG4 reactive power instruction:

[0184] Q CA11 = Q C4 = -Q minA11 = -Q min4 = -2

[0185] The available reactive power values ​​of the three SVG units at the power station are 1.25 Mvar, 1.25 Mvar, and -2 Mvar, respectively, totaling 0.5, which is related to the total reactive power demand Q. req =0.5Mvar matches.

[0186] The reactive power command matrix for the three usable SVG units is: Q C = [1.25, 1.25, -2].

[0187] Special Note: This example illustrates an application scenario where the total number of SVGs (4) at the site exceeds the number of available SVGs (3). Reactive power dead-zone offsetting is performed based on the available SVGs. This scenario is common in real-world applications; for example, one SVG might require maintenance due to module bypass or periodic equipment repair, while the remaining SVGs continue to operate normally. The reactive power dead-zone offsetting allocation strategy of this invention has the ability to dynamically adjust the allocation of reactive power commands based on SVG availability information.

[0188] Example 2: Figure 5 This is a schematic diagram of the station SVG reactive dead zone offset distribution device in Embodiment 2 of the present invention.

[0189] like Figure 5 As shown, the station SVG reactive power dead zone offsetting distribution device of this embodiment includes:

[0190] The instruction generation module is used to generate total reactive power demand.

[0191] The iterative solution module is used to iteratively solve the minimum constraint objective T. min and their corresponding A1, A2, Q M1 and Q M2 .

[0192] The reactive power instruction allocation calculation module is used to calculate the reactive power instructions allocated to each available SVG.

[0193] The reactive power command distribution module is used to distribute reactive power commands to each available SVG.

[0194] The SVG reactive power dead zone offsetting distribution device provided in this embodiment achieves precise distribution of multiple available SVG reactive power within the station through the cooperation between various modules.

[0195] Specifically, after receiving the total reactive power command (total reactive power demand) from the command generation module, the minimum constraint target T is determined during iteration by combining information such as the number of SVGs configured in the power station, the number of available SVGs, the rated capacity of SVGs, and the reactive power dead zone of SVGs. min The calculation method is based on the minimum constraint objective T. min The calculation method involves an iterative solution module to determine the minimum constraint objective T. minAnd save the minimum constraint objective T min The corresponding A1, A2, Q M1 and Q M2 Based on the total reactive power command value and the minimum constraint target T min The reactive power command allocation calculation module calculates the reactive power allocation command for each available SVG, and the reactive power command issuing module issues the reactive power command to each available SVG, thus realizing the accurate allocation of reactive power for multiple available SVGs in the station.

[0196] Furthermore, in the SVG reactive dead zone offset distribution device of this embodiment, the total reactive power demand (total reactive power command) can be derived from an external system, such as AVC or a scheduling system; the total reactive power command can also be generated by the internal voltage closed loop of the device or directly set by the device.

[0197] In this invention, unless otherwise explicitly specified and limited, the first feature being "on" or "below" the second feature can mean that the first feature and the second feature are in direct contact, or that the first feature and the second feature are in indirect contact through an intermediate medium.

[0198] Furthermore, "above," "on top of," and "above" the first feature in relation to the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "under," and "beneath" the first feature in relation to the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0199] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0200] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A reactive power dead zone offsetting allocation strategy for power station SVG, characterized in that, Includes the following steps; S1 obtains application site information, including: Obtain the matrix S of all SVG numbers for the site A S A = [1, 2, ..., N], where N represents the total number of SVGs in the station; Obtain the rated capacity matrix Q of the SVG n Q n =[Q n1 Q n2 Q nN ], Q ni This represents the rated capacity corresponding to SVG numbered i, and also represents matrix Q. n The i-th element; Obtain the reactive dead zone matrix Q of SVG min Q min =[Q min1 Q min2 Q minN ], Q mini This indicates that the SVG with the number i corresponds to the reactive power dead zone, and also represents the matrix Q. min The i-th element; Obtain the available SVG number matrix A for the site, A = [d1, d2, ..., d n ], where n represents the total number of available SVGs; Create a first combination matrix A1 for available SVG numbers to store the final output instructions and Q. req Numerical values ​​with opposite signs can be numbered using SVG, A1 = [e1, e2, ..., e m ], m represents the relationship with Q req The number of available SVGs with opposite numerical signs; Create a second combined matrix A2 containing available SVG numbers to store the final output instructions and Q. req Numerical signs that are the same can be represented by SVG numbers, A2 = [f1, f2, ..., f n-m ], nm represents the relationship with Q req The number of available SVGs with the same numerical sign; The sum of the rated capacities Q corresponding to the SVG numbers in matrix A is obtained. nA : Obtain the sum of the rated capacity of the SVG number corresponding to matrix A1. The sum of the rated capacity of the SVG number corresponding to matrix A2 is obtained. Obtain the cumulative sum of reactive dead zones Q corresponding to the SVG number of matrix A. M : The reactive dead zone sum Q corresponding to the SVG number in matrix A1 is obtained. M1 : The reactive dead zone sum Q corresponding to the SVG number in matrix A2 is obtained. M2 : Among them, A i d represents the i-th element in matrix A i A 1j Represents the j-th element e in matrix A1 j A 2k f represents the k-th element in matrix A2 k ; S2 obtains the total reactive power requirement Q. req ; S3 is based on the total reactive power demand Q req Determine the minimum constraint objective T min Calculation methods include: If Q req If T ≥ 0, then T min =Q req +Q M1 -Q M2 ; If Q req <0, then T min =-Q req +Q M1 -Q M2 ; S4 Iteratively solves the minimum constraint objective T min And store the corresponding calculation results, including: Initial assignment T min =T min0 =Q nA ; Take any one or more values ​​from matrix A to form the first combined matrix A1, and iterate sequentially as follows: First iteration; A1=[1], then Q M1 =Q min1 ,A2=[2,3,...,n],Q M2 =Q M -Q M1 T is calculated based on the calculation method determined in step S3. min ; If |T min |<|T min0 |、or|T min |=|T min0 |and T min >0 and T min0 <0, then T min0 =T min And store the corresponding A1, A2, Q M1 and Q M2 ; If |T min |>|T min0 |, then do not update T min0 And continue iterative calculations; Second iteration: A1 = [2], then Q M1 =Q min2 ,A2=[1,3,...,n],Q M2 =Q M -Q M1 T is calculated based on the calculation method determined in step S3. min ; If |T min |<|T min0 |、or|T min |=|T min0 |and T min >0 and T min0 <0, then T min0 =T min And store the corresponding A1, A2, Q M1 and Q M2 ; If |T min |>|T min0 |, then do not update T min0 And continue iterative calculations; …… No. (2 n -1) iterations: A1 = [1, 2, ..., n], then Q M1 =Q M A2 = [], Q M2 =Q M -Q M1 =0, T is calculated based on the calculation method determined in step S3. min ; If |T min |<|T min0 |), or |T min |=|T min0 |and T min >0 and T min0 <0, then T min0 =T min And store the corresponding A1, A2, Q M1 and Q M2 ; If |T min |>|T min0 |, then do not update T min0 ; The iteration ends, and the minimum constraint objective T is stored. min and their corresponding A1, A2, Q M1 And Q M2 ; S5 is based on the total reactive power demand and the minimum constraint target T. min Determine the reactive power allocation strategy corresponding to each available SVG to obtain the reactive power instruction matrix, including: If Q req ≥0 and T min If ≥0, then the reactive power instruction allocation for each available SVG is as follows: If Q req ≥0 and T min If <0, the reactive power instruction allocation for each available SVG is as follows: If Q req <0 and T min If ≥0, then the reactive power instruction allocation for each available SVG is as follows: If Q req <0 and T min If <0, the reactive power instruction allocation for each available SVG is as follows: Obtain the usable SVG reactive power instruction matrix Q C Q C =[Q CA1 Q CA2 Q CAn ]; in, Indicates that the number is A i SVG reactive power instructions, Indicates that the number is A 1j SVG reactive power instructions, Indicates that the number is A 2k SVG reactive commands.

2. A distribution device for implementing the reactive power dead zone offsetting distribution strategy of the station SVG as described in claim 1, characterized in that, include: The instruction generation module is used to generate the total reactive power demand; The iterative solution module is used to iteratively solve the minimum constraint objective T. min and their corresponding A1, A2, Q M1 and Q M2 ; The reactive power instruction allocation calculation module is used to calculate the reactive power instructions allocated to each available SVG; The reactive power command distribution module is used to distribute reactive power commands to each available SVG.

3. The allocation device for the reactive power dead zone offset allocation strategy of the station SVG according to claim 2, characterized in that, The total reactive power demand originates from external systems or internal devices.

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