New energy station topology fine equivalence and automatic verification method

Abstract

The invention relates to the technical field of new energy station modeling, and provides a new energy station topology fine equivalence and automatic verification method. The method comprises the following steps: step 1, constructing structured modeling data of a new energy station; 2, PSASP software is operated through an RPA tool to complete automatic modeling of the new energy station; 3, calculating current collection line loss, box transformer loss and topological equivalent impedance based on a load flow calculation result of the PSASP software; and step 4, iteratively modifying the numerical values of the PSASP software transient stability fault card grounding fault R and X according to different high / low voltage ride-through verification working conditions until the new energy station grid-connected point voltage Ufault is consistent with the set verification working condition voltage Uset during the fault ride-through period. According to the scheme of the invention, joint modeling based on the RPA tool and the PSASP software greatly improves the modeling work quality and efficiency of the new energy station, thereby guaranteeing the stable operation and optimal scheduling of the new energy power system.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy station modeling, and in particular relates to a new energy station topology fine equivalence and automatic verification method. Background Art

[0002] The high proportion of new energy access systems has squeezed the power generation space of conventional units, and traditional rotating synchronous equipment has been gradually replaced by large-scale power electronic equipment, and the operation characteristics of the power grid have undergone profound changes. Carrying out large-scale power system simulation analysis is an important means to enhance the understanding of the characteristics of new power systems, guide the arrangement of power grid operation modes, and ensure the safe and stable operation of the system. However, unlike the AC power grid simulation dominated by traditional synchronous machines, the large number of new energy stations and their components, and the complex control process of power electronic devices have seriously restricted the simulation and calculation efficiency of new energy power systems. Equivalent modeling of new energy stations is an effective method that takes into account both the simulation and calculation efficiency of large-scale power systems and the dynamic response characteristics of new energy stations.

[0003] The single-machine multiplication model uses a single renewable energy unit to be equivalent to the entire station, making its external characteristics tend to be consistent. Currently, renewable energy stations in large power grid simulation generally use this model. Although this simplification can reduce the model order and simulation calculation amount of renewable energy stations, the model does not consider the characteristic differences between different types of single machines, and cannot reflect the impedance distribution within the station. For multiple renewable energy units connected by long-distance collector lines, due to the different voltage distribution at the machine end along the line, the response characteristics of each unit during low voltage ride-through are not the same. Summary of the invention

[0004] The present invention provides a new energy station topology fine equivalence and automatic verification method, which can improve the technical problems of low modeling efficiency and insufficient equivalence accuracy of new energy station modeling technology in related technologies.

[0005] The present invention provides a new energy site topology fine equivalence and automatic verification method, comprising the following steps: Step 1: Constructing structured modeling data of new energy stations: Constructing structured modeling data of new energy stations including unit parameters, line parameters, box transformer parameters, busbar modeling, unit modeling, box transformer modeling and collector line modeling; Step 2: Design an automatic modeling process for new energy stations based on RPA tools: Use the RPA tool to operate the PSASP software to complete the construction of new energy station projects, read the structured modeling data of new energy stations, and automatically model busbars, AC lines, transformers, and generators; Step 3: Calculate the topological equivalent impedance based on the PSASP power flow result report: Calculate the collector line loss, box transformer loss and topological equivalent impedance based on the power flow calculation results of the PSASP software; The specific steps are: run the power flow calculation program of PSASP software to generate power flow results, export the result report data of the physical bus and the two-winding transformer respectively, and calculate the collector line loss, box transformer loss and topological equivalent impedance based on the result report data; Step 4: According to the different high / low voltage ride-through verification conditions, iteratively modify the values ​​of ground fault R and X of the transient stability fault card of the PSASP software until the voltage U of the grid connection point of the new energy station during the fault ride-through period is fault Verification condition voltage U set consistent; where R is the grounding resistance and X is the grounding reactance.

[0006] A method for fine equivalence and automatic verification of the topology of a new energy station provided by the present invention has at least the following technical effects: by constructing structured modeling data of new energy stations, designing an automatic modeling process for new energy stations based on RPA tools, calculating the topological equivalent impedance based on the PSASP flow result report, and automatically verifying the calibration condition impedance based on the PSASP software loop call, efficient modeling and accurate equivalence verification of new energy stations are achieved based on joint modeling of RPA tools and PSASP software, which greatly improves the quality and efficiency of new energy station modeling work, thereby ensuring the stable operation and optimized scheduling of the new energy power system.

[0007] Furthermore, the step 1 comprises the following steps: Step 101: Construct a structured modeling data group that can be read by the RPA tool: obtain the modeling parameters of the new energy station, including the type and capacity of the new energy station, the parameters of the box transformer, and the measured parameters of the converter fault ride-through characteristics; and obtain the topology modeling parameters of the new energy station, including the primary system diagram of the new energy station, the cable direction diagram of the collector line, and the parameters of the step-up transformer; The box transformer parameters include capacity, short-circuit voltage percentage, short-circuit loss, no-load loss and no-load current percentage, the collector line cable trend diagram includes the collector line model and length, and the step-up transformer parameters include capacity, short-circuit voltage percentage, short-circuit loss, no-load loss and no-load current percentage; Step 102: constructing a unit parameter structured modeling data group, including generator index, generator rated capacity, generator model type and parameter group number; Step 103: constructing a line parameter structured modeling data group, including line index, line type, unit length positive sequence resistance, unit length positive sequence reactance, unit length positive sequence susceptance, unit length zero sequence resistance, unit length zero sequence reactance and unit length zero sequence susceptance; Step 104: construct a structured modeling data set of box-type transformer parameters, including transformer index, transformer rated capacity, short-circuit loss, short-circuit voltage percentage, no-load loss and no-load current percentage; Step 105: construct a busbar modeling structured modeling data group, including a busbar index, a reference voltage, a voltage upper limit, and a voltage lower limit; Step 106: constructing a unit modeling structured modeling data group, including the unit name, access bus and generator type, wherein the generator type is consistent with the generator index number of step 102; Step 107: constructing a structured modeling data group for collector line modeling, including the collector line name, I-side busbar, J-side busbar, line index and line length, wherein the line type is consistent with the line index number of step 103; Step 108: construct a structured modeling data group for the box-type transformer modeling, including the box-type transformer name, high-voltage side bus, low-voltage side bus, and box-type transformer type. The box-type transformer type is consistent with the transformer index number of step 104.

[0008] Furthermore, the step 2 comprises the following steps: The step 2 comprises the following steps: Step 201: Create a new energy station project: Use the RPA tool to open the application, create a new energy station project, name it, and save it; Step 202: Reading the structured modeling data of the new energy station: using the RPA tool to read the structured modeling data of the new energy station constructed in step 1, and storing it in the line parameters, generator parameters, transformer parameters, busbar modeling, generator modeling, transformer modeling and collector modeling variables; Step 203: Automatic bus modeling: Open the component data bus, use the RPA tool to loop through the bus modeling variables one by one, and fill in the bus name, reference voltage, upper voltage limit, and lower voltage limit; Step 204: Automatic modeling of AC lines: Open the component data AC line, use the RPA tool to loop through the collector line modeling variables one by one, and fill in the collector line name, I-side busbar, and J-side busbar; The unit length line parameter reads the line parameter variable, and the AC line impedance phasor is calculated as: [R 1L ,X 1L ,B 1L ,R 0L ,X 0L ,B 1L ] = [R1,X1,B1,R0,X0,B0]×L; Where: R 1L , X 1L , B 1L , R 0L , X 0L and B 1LThey are the total positive-sequence resistance, total positive-sequence reactance, total positive-sequence susceptance, total zero-sequence resistance, total zero-sequence reactance and total zero-sequence susceptance of the AC line respectively; R1, X1, B1, R0, X0 and B0 are the positive-sequence resistance per unit length, positive-sequence reactance per unit length, positive-sequence susceptance per unit length, zero-sequence resistance per unit length, zero-sequence reactance per unit length and zero-sequence susceptance per unit length of the AC line respectively; L is the length of each line section; Step 205: Automatic transformer modeling: Open the two-winding transformer in the component data, use the RPA tool to loop through the transformer modeling variables one by one, and fill in the name of the box transformer, the high-voltage side bus, the low-voltage side bus, and the box transformer capacity; Calculate the transformer resistance R T , Transformer Reactance X T , Transformer conductivity G T And transformer susceptance B T ; It is expressed as: R T =P k / 1000*U N 2 / S N 2 ; Where: R T is the transformer resistance, P k is the transformer short-circuit loss, U N is the transformer rated voltage and S N is the rated capacity of the transformer; and, X T = U k % / 100*U N 2 / S N ; Where: X T is the transformer reactance, U k % is the transformer short-circuit voltage percentage, U N is the transformer rated voltage and S N is the rated capacity of the transformer; and, G T = ΔP0 / U N 2 ×10 -3 ; Where: G T is the transformer conductance, ΔP0 is the transformer no-load loss and U N is the rated voltage of the transformer; and, B T = I0% / 100*S N / U N 2 ; Where: BT is the transformer susceptance, I0% is the transformer no-load current percentage, U N is the transformer rated voltage and S N is the rated capacity of the transformer; Step 206: Automatic generator modeling: Open the component data generator and regulator, use the RPA tool to loop through the generator modeling variables one by one, and fill in the unit name, access bus, generator type, generator rated capacity, generator model type and parameter group number.

[0009] Furthermore, the step 3 comprises the following steps: Step 301: Divide the renewable energy station units G into M groups according to the types, capacities and control performance differences of the renewable energy station units, and set them as: G={G1,G2,...,G i ,...,G M}, G i For the i-th group, i={1,2,...,M}, the corresponding box transformer T is set to: T={T1,T2,...,T i ,...,T M}; There are N units in the i-th group, set as: G i ={G i1 ,G i2 ,...,G ij ,...,G iN}, G ij The i-th group has j units, j={1,2,...,N}, and the corresponding box transformer T i Set to: T i ={T i1 ,T i2 ,...,T ij ,...,T iN}; Step 302: Read the bus voltage phasor U at the low voltage side of the grid connection point according to the result report data of the physical bus BusPOIL , Unit G ij 35 kV bus voltage U Busij 、Box Transformer T ij High voltage side power S H-Busij And box transformer T ij Low voltage side power S L-Busij ; Calculate the unit G ij The generated power flows through the collection line to the grid connection point, and the apportioned loss is: ; Where: U Busij For unit G ij 35 kV bus voltage, U BusPOILis the bus voltage phase quantity on the low voltage side of the grid connection point and S H-Busij For box transformer T ij High voltage side power; Box transformer T ij The resulting loss is: ; Where: S L-Busij For box transformer T ij Low voltage side power and S H-Busij For box transformer T ij High voltage side power; Step 303: After accumulating the losses of each collector line of cluster i, the total collector line loss of cluster i is obtained as follows: ; Where: is the total collector line loss of group i, k is the kth unit in group i and is the power loss of the kth unit in the cluster i on the collector circuit; After accumulating the losses of each box transformer in cluster i, the total box transformer loss of cluster i is: ; In the formula, is the total transformer loss of cluster i; k is the sum of the kth transformer in cluster i is the loss of the kth box transformer in cluster i; Step 304: The equivalent collector line impedance of computer group i is: ; In the formula, is the equivalent collector line impedance of cluster i, is the total collection line loss of cluster i, U BusPOIL is the bus voltage phase quantity and For box transformer T ij The sum of the power on the low voltage side; The equivalent transformer impedance of computer group i is: ; In the formula, is the equivalent box transformer impedance of cluster i, is the total box transformer loss of cluster i, U BusPOIL is the bus voltage phase quantity and For box transformer T ij The sum of the low voltage side powers.

[0010] Furthermore, step 4 includes the following steps: Step 401: Given the initial values ​​of the fault card grounding impedance R and X as 0, where R is the grounding resistance and X is the grounding reactance, obtain the fault response curve of the new energy station through transient simulation, and read the voltage U during the fault period fault ; Step 402: If |U fault -Uset |>ɛ U , ɛ U That is the allowable voltage deviation; Where U fault is the voltage during the fault and U set To verify the working voltage; Then continue to increase the ground impedance value according to the ΔR and ΔX steps: R nxt =R pre +ΔR; Where: R nxt For the next transient simulation ground resistance, R pre is the ground resistance of this transient simulation and ΔR is the resistance change step; and, X nxt =X pre +ΔX; Where: X nxt Simulate the grounding reactance, X for the next transient pre is the grounding reactance for this transient simulation and ΔX is the reactance change step. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0012] Figure 1 A flowchart of a new energy station topology fine equivalence and automatic verification method provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0013] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention 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 invention and are not intended to limit the present invention.

[0014] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs; the terms used herein are only for the purpose of describing specific embodiments rather than limiting the present invention.

[0015] In order to improve the technical problems of low modeling efficiency and insufficient equivalent accuracy of new energy station modeling technology in related technologies, the embodiments of the present invention provide the following solutions.

[0016] like Figure 1 As shown, an embodiment of the present invention provides a new energy site topology fine equivalence and automatic verification method, comprising the following steps: Step 1: Constructing structured modeling data of new energy stations: Constructing structured modeling data of new energy stations including unit parameters, line parameters, box transformer parameters, busbar modeling, unit modeling, box transformer modeling and collector line modeling; Step 2: Design an automatic modeling process for new energy stations based on RPA tools: Use the RPA tool to operate the PSASP software to complete the construction of new energy station projects, read the structured modeling data of new energy stations, and automatically model busbars, AC lines, transformers, and generators; Step 3: Calculate the topological equivalent impedance based on the PSASP power flow result report: Calculate the collector line loss, box transformer loss and topological equivalent impedance based on the power flow calculation results of the PSASP software; Step 4: According to the different high / low voltage ride-through verification conditions, iteratively modify the values ​​of ground fault R and X of the transient stability fault card of the PSASP software until the voltage U of the grid connection point of the new energy station during the fault ride-through period is fault Verification condition voltage U set consistent; where R is the grounding resistance and X is the grounding reactance.

[0017] It can be understood that in order to take into account both the simulation calculation accuracy and calculation efficiency of new energy stations, it is necessary to reasonably group the units according to the differences in response characteristics of each unit, and consider the network topology to calculate the equivalent parameters of each cluster.

[0018] By constructing structured modeling data for new energy stations, designing an automatic modeling process for new energy stations based on RPA tools, calculating the topological equivalent impedance based on the PSASP flow result report, and automatically verifying the verification condition impedance based on the PSASP software loop call, the joint modeling based on RPA tools and PSASP software is used to achieve efficient modeling and accurate equivalent verification of new energy stations, greatly improving the quality and efficiency of new energy station modeling work, thereby ensuring the stable operation and optimized scheduling of the new energy power system.

[0019] Specifically, in some embodiments, the specific steps of step 3 are: running the power flow calculation program of the PSASP software to generate power flow results, exporting the result report data of the physical bus and the two-winding transformer respectively, and calculating the collection line loss, box transformer loss and topological equivalent impedance based on the result report data.

[0020] Specifically, in some embodiments, step 1 includes the following steps: The step 1 comprises the following steps: Step 101: Construct a structured modeling data group that can be read by the RPA tool: obtain the modeling parameters of the new energy station, including the type and capacity of the new energy station, the parameters of the box transformer, and the measured parameters of the converter fault ride-through characteristics; and obtain the topology modeling parameters of the new energy station, including the primary system diagram of the new energy station, the cable direction diagram of the collector line, and the parameters of the step-up transformer; It can be understood that the parameters of the box transformer include capacity, short-circuit voltage percentage, short-circuit loss, no-load loss and no-load current percentage, the cable trend diagram of the collector line includes the model and length of the collector line, and the parameters of the step-up transformer include capacity, short-circuit voltage percentage, short-circuit loss, no-load loss and no-load current percentage; Step 102: constructing a unit parameter structured modeling data group, including a generator index, a generator rated capacity, a generator model type, and a parameter group number; It can be understood that the generator model types are type 12 double-fed wind turbine, type 13 direct-drive wind turbine, and type 14 centralized photovoltaic; Step 103: constructing a line parameter structured modeling data group, including line index, line type, unit length positive sequence resistance, unit length positive sequence reactance, unit length positive sequence susceptance, unit length zero sequence resistance, unit length zero sequence reactance and unit length zero sequence susceptance; Step 104: construct a structured modeling data set of box-type transformer parameters, including transformer index, transformer rated capacity, short-circuit loss, short-circuit voltage percentage, no-load loss and no-load current percentage; Step 105: construct a busbar modeling structured modeling data group, including a busbar index, a reference voltage, a voltage upper limit, and a voltage lower limit; Step 106: constructing a unit modeling structured modeling data group, including the unit name, access bus and generator type, wherein the generator type is consistent with the generator index number of step 102; Step 107: constructing a structured modeling data group for collector line modeling, including the collector line name, I-side busbar, J-side busbar, line index and line length, wherein the line type is consistent with the line index number of step 103; Step 108: construct a structured modeling data group for the box-type transformer modeling, including the box-type transformer name, high-voltage side bus, low-voltage side bus, and box-type transformer type, where the box-type transformer type is consistent with the transformer index number of step 104.

[0021] Specifically, in some embodiments, step 2 includes the following steps: Step 201: Create a new energy station project: Use the RPA tool to open the application, create a new energy station project, name it, and save it; Step 202: Reading the structured modeling data of the new energy station: using the RPA tool to read the structured modeling data of the new energy station constructed in step 1, and storing it in the line parameters, generator parameters, transformer parameters, busbar modeling, generator modeling, transformer modeling and collector modeling variables; Step 203: Automatic bus modeling: Open the component data bus, use the RPA tool to loop through the bus modeling variables one by one, and fill in the bus name, reference voltage, upper voltage limit, and lower voltage limit; Step 204: Automatic modeling of AC lines: Open the component data AC line, use the RPA tool to loop through the collector line modeling variables one by one, and fill in the collector line name, I-side busbar, and J-side busbar; The unit length line parameter reads the line parameter variable, and the AC line impedance phasor is calculated as: [R 1L ,X 1L ,B 1L ,R 0L ,X 0L ,B 1L ] = [R1,X1,B1,R0,X0,B0]×L; Where: R 1L , X 1L , B 1L , R 0L , X 0L and B 1L They are the total positive-sequence resistance, total positive-sequence reactance, total positive-sequence susceptance, total zero-sequence resistance, total zero-sequence reactance and total zero-sequence susceptance of the AC line respectively; R1, X1, B1, R0, X0 and B0 are the positive-sequence resistance per unit length, positive-sequence reactance per unit length, positive-sequence susceptance per unit length, zero-sequence resistance per unit length, zero-sequence reactance per unit length and zero-sequence susceptance per unit length of the AC line respectively; L is the length of each line section; Step 205: Automatic transformer modeling: Open the two-winding transformer in the component data, use the RPA tool to loop through the transformer modeling variables one by one, and fill in the name of the box transformer, the high-voltage side bus, the low-voltage side bus, and the box transformer capacity; Calculate the transformer resistance R T , Transformer Reactance X T , Transformer conductivity G T And transformer susceptance B T ; It is expressed as: R T =P k / 1000*U N 2 / S N 2 ; Where: R T is the transformer resistance, P kis the transformer short-circuit loss, U N is the transformer rated voltage and S N is the rated capacity of the transformer; and, X T = U k % / 100*U N 2 / S N ;

[0022] Where: X T is the transformer reactance, U k % is the transformer short-circuit voltage percentage, U N is the transformer rated voltage and S N is the rated capacity of the transformer; and, G T = ΔP0 / U N 2 ×10 -3 ; Where: G T is the transformer conductance, ΔP0 is the transformer no-load loss and U N is the rated voltage of the transformer; and, B T = I0% / 100*S N / U N 2 ; Where: B T is the transformer susceptance, I0% is the transformer no-load current percentage, U N is the transformer rated voltage and S N is the rated capacity of the transformer; Step 206: Automatic generator modeling: Open the component data generator and regulator, use the RPA tool to loop through the generator modeling variables one by one, and fill in the unit name, access bus, generator type, generator rated capacity, generator model type and parameter group number.

[0023] Specifically, in some embodiments, step 3 includes the following steps: Step 301: Divide the renewable energy station units G into M groups according to the types, capacities and control performance differences of the renewable energy station units, and set them as: G={G1,G2,...,G i ,...,G M}, G i For the i-th group, i={1,2,...,M}, the corresponding box transformer T is set to: T={T1,T2,...,T i ,...,T M}; There are N units in the i-th group, set as: G i ={G i1,G i2 ,...,G ij ,...,G iN}, G ij The i-th group has j units, j={1,2,...,N}, and the corresponding box transformer T i Set to: T i ={T i1 ,T i2 ,...,T ij ,...,T iN}; Step 302: Read the bus voltage phasor U at the low voltage side of the grid connection point according to the result report data of the physical bus BusPOIL , Unit G ij 35 kV bus voltage U Busij 、Box Transformer T ij High voltage side power S H-Busij And box transformer T ij Low voltage side power S L-Busij ; Calculate the unit G ij The generated power flows through the collection line to the grid connection point, and the apportioned loss is: ; Where: U Busij For unit G ij 35 kV bus voltage, U BusPOIL is the bus voltage phase quantity on the low voltage side of the grid connection point and S H-Busij For box transformer T ij High voltage side power; Box transformer T ij The resulting loss is: ; Where: S L-Busij For box transformer T ij Low voltage side power and S H-Busij For box transformer T ij High voltage side power; Step 303: After accumulating the losses of each collector line of cluster i, the total collector line loss of cluster i is obtained as follows: ; Where: is the total collector line loss of group i, k is the kth unit in group i and is the power loss of the kth unit in the cluster i on the collector circuit; After accumulating the losses of each box transformer in cluster i, the total box transformer loss of cluster i is: ; In the formula, is the total transformer loss of cluster i; k is the sum of the kth transformer in cluster i is the loss of the kth box transformer in cluster i; Step 304: The equivalent collector line impedance of computer group i is: ; In the formula, is the equivalent collector line impedance of cluster i, is the total collection line loss of cluster i, U BusPOIL is the bus voltage phase quantity and For box transformer T ij The sum of the power on the low voltage side; The equivalent transformer impedance of computer group i is: ; In the formula, is the equivalent box transformer impedance of cluster i, is the total box transformer loss of cluster i, U BusPOIL is the bus voltage phase quantity and For box transformer T ij The sum of the low voltage side powers.

[0024] Specifically, in some embodiments, step 4 includes the following steps: Step 401: Given the initial values ​​of the fault card grounding impedance R and X as 0, where R is the grounding resistance and X is the grounding reactance, obtain the fault response curve of the new energy station through transient simulation, and read the voltage U during the fault period fault ; Step 402: If |U fault -U set |>ɛ U , ɛ U That is the allowable voltage deviation; Where U fault is the voltage during the fault and U set To verify the working voltage; Then continue to increase the ground impedance value according to the ΔR and ΔX steps: R nxt =R pre +ΔR; Where: R nxt For the next transient simulation ground resistance, R pre is the ground resistance of this transient simulation and ΔR is the resistance change step; and, X nxt =X pre +ΔX; Where: X nxt Simulate the grounding reactance, X for the next transient pre is the grounding reactance for this transient simulation and ΔX is the reactance change step. Example 1

[0025] The actual wind farm topology includes 6 collector lines, each of which is radial and connected to 7 to 10 2.5 MW or 3.2 MW wind turbines. All power is collected through the 35 kV bus and then boosted and sent out. The structured modeling information of unit parameters is shown in Table 1, the structured modeling information of line parameters is shown in Table 2, the structured modeling information of box transformer parameters is shown in Table 3, the structured modeling information of bus modeling is shown in Table 4, the structured modeling information of unit modeling is shown in Table 5, the structured modeling information of box transformer modeling is shown in Table 6, and the structured modeling information of collector line modeling is shown in Table 7.

[0026] Table 1 Unit parameter structured modeling data set

[0027] Table 2 Line parameter structured modeling data set

[0028] Table 3. Data set of structural modeling of box-type transformer parameters

[0029] Table 4 Busbar modeling structured modeling data set

[0030] Table 5 Unit modeling structured modeling data group

[0031] Table 6: Structured modeling data set for box-type transformer modeling

[0032] Table 7: Data set for structured modeling of collector line modeling

[0033] Through the RPA tool, PSASP software is operated to complete the new construction of new energy station projects, the reading of structured modeling data of new energy stations, automatic busbar modeling, automatic AC line modeling, automatic transformer modeling and automatic generator modeling.

[0034] After the automatic modeling is completed, the flow result report is exported and the 51 units of the station are divided into 2 groups. Numbers G91~G122 are the first group, with active power loss of the collector line of 2.61 MW, reactive power loss of the collector line of 5.30 MW, active power loss of the box transformer of 0.65 MW, reactive power loss of the box transformer of 4.62 MW, equivalent resistance of the collector line of 0.0423 pu, equivalent reactance of the collector line of 0.0861 pu, short-circuit loss of the box transformer of 812.60 kW, and short-circuit voltage percentage of the box transformer of 6.60%; numbers G123~G141 are the second group, with active power loss of the collector line of 0.57 MW, reactive power loss of the collector line of 1.02 MW, active power loss of the box transformer of 0.48 MW, reactive power loss of the box transformer of 3.85 MW, equivalent resistance of the collector line of 0.016 pu, equivalent reactance of the collector line of 0.0281 pu, short-circuit loss of the box transformer of 569.90 kW, and short-circuit voltage percentage of the box transformer of 6.93%.

[0035] The low voltage ride-through verification condition is set to 0.1pu, and the grounding resistance and reactance are obtained through cyclic iteration, which are 0.031pu and 0.031pu, respectively, with a comparison error of 3×10e -4 .

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A new energy station topology fine equivalence and automatic verification method, characterized in that: The following steps are involved: Step 1: Construct new energy station structured modeling data including unit parameters, line parameters, box transformer parameters, busbar modeling, unit modeling, box transformer modeling and collector line modeling; Step 2: Use the RPA tool to operate the PSASP software to complete the construction of new energy station projects, read the structured modeling data of new energy stations, and automatically model the busbars, AC lines, transformers, and generators. Step 3: Calculate the collector line loss, transformer loss and topology equivalent impedance based on the power flow calculation results of PSASP software; Step 4: According to the different high / low voltage ride-through verification conditions, iteratively modify the values ​​of ground fault R and X of the transient stability fault card of the PSASP software until the voltage U of the grid connection point of the new energy station during the fault ride-through period is fault Verification condition voltage U set consistent; where R is the grounding resistance and X is the grounding reactance.

2. The new energy station topology fine equivalence and automatic verification method according to claim 1 is characterized in that: The step 1 comprises the following steps: Step 101: Construct a structured modeling data group that can be read by the RPA tool: obtain the modeling parameters of the new energy station, including the type and capacity of the new energy station, the parameters of the box transformer, and the measured parameters of the converter fault ride-through characteristics; and obtain the topology modeling parameters of the new energy station, including the primary system diagram of the new energy station, the cable direction diagram of the collector line, and the parameters of the step-up transformer; Step 102: constructing a unit parameter structured modeling data group, including generator index, generator rated capacity, generator model type and parameter group number; Step 103: constructing a line parameter structured modeling data group, including line index, line type, unit length positive sequence resistance, unit length positive sequence reactance, unit length positive sequence susceptance, unit length zero sequence resistance, unit length zero sequence reactance and unit length zero sequence susceptance; Step 104: construct a structured modeling data set of box-type transformer parameters, including transformer index, transformer rated capacity, short-circuit loss, short-circuit voltage percentage, no-load loss and no-load current percentage; Step 105: construct a busbar modeling structured modeling data group, including a busbar index, a reference voltage, a voltage upper limit, and a voltage lower limit; Step 106: constructing a unit modeling structured modeling data group, including the unit name, access bus and generator type, wherein the generator type is consistent with the generator index number of step 102; Step 107: constructing a structured modeling data group for collector line modeling, including the collector line name, I-side busbar, J-side busbar, line index and line length, wherein the line type is consistent with the line index number of step 103; Step 108: construct a structured modeling data group for the box-type transformer modeling, including the box-type transformer name, high-voltage side bus, low-voltage side bus, and box-type transformer type. The box-type transformer type is consistent with the transformer index number of step 104.

3. The new energy station topology fine equivalence and automatic verification method according to claim 2 is characterized by: In step 101, the box transformer parameters include capacity, short-circuit voltage percentage, short-circuit loss, no-load loss and no-load current percentage, the collector line cable route diagram includes the collector line model and length, and the step-up transformer parameters include capacity, short-circuit voltage percentage, short-circuit loss, no-load loss and no-load current percentage.

4. The new energy station topology fine equivalence and automatic verification method according to claim 1 is characterized in that: The step 2 comprises the following steps: Step 201: Create a new energy station project: Use the RPA tool to open the application, create a new energy station project, name it, and save it; Step 202: Reading the structured modeling data of the new energy station: using the RPA tool to read the structured modeling data of the new energy station constructed in step 1, and storing it in the line parameters, generator parameters, transformer parameters, busbar modeling, generator modeling, transformer modeling and collector modeling variables; Step 203: Automatic bus modeling: Open the component data bus, use the RPA tool to loop through the bus modeling variables one by one, and fill in the bus name, reference voltage, upper voltage limit, and lower voltage limit; Step 204: Automatic modeling of AC lines: Open the component data AC line, use the RPA tool to loop through the collector line modeling variables one by one, and fill in the collector line name, I-side busbar, and J-side busbar; The unit length line parameter reads the line parameter variable, and the AC line impedance phasor is calculated as: [R 1L ,X 1L ,B 1L ,R 0L ,X 0L ,B 1L ] = [R1,X1,B1,R0,X0,B0]×L; Where: R 1L , X 1L , B 1L , R 0L , X 0L and B 1L They are the total positive-sequence resistance, total positive-sequence reactance, total positive-sequence susceptance, total zero-sequence resistance, total zero-sequence reactance and total zero-sequence susceptance of the AC line respectively; R1, X1, B1, R0, X0 and B0 are the positive-sequence resistance per unit length, positive-sequence reactance per unit length, positive-sequence susceptance per unit length, zero-sequence resistance per unit length, zero-sequence reactance per unit length and zero-sequence susceptance per unit length of the AC line respectively; L is the length of each line section; Step 205: Automatic transformer modeling: Open the two-winding transformer in the component data, use the RPA tool to loop through the transformer modeling variables one by one, and fill in the name of the box transformer, the high-voltage side bus, the low-voltage side bus, and the box transformer capacity; Calculate the transformer resistance R T , Transformer Reactance X T , Transformer conductivity G T And transformer susceptance B T ; It is expressed as: R T = P k / 1000*U N 2 / S N 2 ; Where: R T is the transformer resistance, P k is the transformer short-circuit loss, U N is the transformer rated voltage and S N is the rated capacity of the transformer; and, X T = U k % / 100*U N 2 / S N ; Where: X T is the transformer reactance, U k % is the transformer short-circuit voltage percentage, U N is the transformer rated voltage and S N is the rated capacity of the transformer; and, G T = ΔP0 / U N 2 ×10 -3 ; Where: G T is the transformer conductance, ΔP0 is the transformer no-load loss and U N is the rated voltage of the transformer; and, B T = I0% / 100*S N / U N 2 ; Where: B T is the transformer susceptance, I0% is the transformer no-load current percentage, U N is the transformer rated voltage and S N is the rated capacity of the transformer; Step 206: Automatic generator modeling: Open the component data generator and regulator, use the RPA tool to loop through the generator modeling variables one by one, and fill in the unit name, access bus, generator type, generator rated capacity, generator model type and parameter group number.

5. The new energy station topology fine equivalence and automatic verification method according to claim 1 is characterized in that: The specific steps of step 3 are: running the power flow calculation program of the PSASP software to generate power flow results, exporting the result report data of the physical bus and the two-winding transformer respectively, and calculating the collector line loss, box transformer loss and topological equivalent impedance based on the result report data.

6. The new energy station topology fine equivalence and automatic verification method according to claim 5 is characterized in that: The step 3 comprises the following steps: Step 301: Divide the renewable energy station units G into M groups according to the types, capacities and control performance differences of the renewable energy station units, and set them as: G={G1,G2,...,G i ,...,G M }, G i For the i-th group, i={1,2,...,M}, the corresponding box transformer T is set to: T={T1,T2,...,T i ,...,T M }; There are N units in the i-th group, set as: G i ={G i1 ,G i2 ,...,G ij ,...,G iN }, G ij The i-th group has j units, j={1,2,...,N}, and the corresponding box transformer T i Set to: T i ={T i1 ,T i2 ,...,T ij ,...,T iN }; Step 302: Read the bus voltage phasor U at the low voltage side of the grid connection point according to the result report data of the physical bus BusPOIL , Unit G ij 35 kV bus voltage U Busij 、Box Transformer T ij High voltage side power S H-Busij And box transformer T ij Low voltage side power S L-Busij ; Calculate the unit G ij The generated power flows through the collection line to the grid connection point, and the apportioned loss is: ; Where: U Busij For unit G ij 35 kV bus voltage, U BusPOIL is the bus voltage phase quantity on the low voltage side of the grid connection point and S H-Busij For box transformer T ij High voltage side power; Box transformer T ij The resulting loss is: ; Where: S L-Busij For box transformer T ij Low voltage side power and S H-Busij For box transformer T ij High voltage side power; Step 303: After accumulating the losses of each collector line of cluster i, the total collector line loss of cluster i is obtained as follows: ; Where: is the total collector line loss of group i, k is the kth unit in group i and is the power loss of the kth unit in the cluster i on the collector circuit; After accumulating the losses of each box transformer in cluster i, the total box transformer loss of cluster i is: ; In the formula, is the total transformer loss of cluster i; k is the sum of the kth transformer in cluster i is the loss of the kth box transformer in cluster i; Step 304: The equivalent collector line impedance of computer group i is: ; In the formula, is the equivalent collector line impedance of cluster i, is the total collection line loss of cluster i, U BusPOIL is the bus voltage phase quantity and For box transformer T ij The sum of the power on the low voltage side; The equivalent transformer impedance of computer group i is: ; In the formula, is the equivalent box transformer impedance of cluster i, is the total box transformer loss of cluster i, U BusPOIL is the bus voltage phase quantity and For box transformer T ij The sum of the low voltage side powers.

7. The new energy station topology fine equivalence and automatic verification method according to claim 1 is characterized in that: The step 4 comprises the following steps: Step 401: Given the initial values ​​of the fault card grounding impedance R and X as 0, where R is the grounding resistance and X is the grounding reactance, obtain the fault response curve of the new energy station through transient simulation, and read the voltage U during the fault period fault ; Step 402: If |U fault -U set |>ɛ U , ɛ U That is the allowable voltage deviation; Where U fault is the voltage during the fault and U set To verify the working voltage; Then continue to increase the ground impedance value according to the ΔR and ΔX steps: R nxt =R pre +ΔR; Where: R nxt For the next transient simulation ground resistance, R pre is the ground resistance of this transient simulation and ΔR is the resistance change step; and, X nxt =X pre +ΔX; Where: X nxt Simulate the grounding reactance, X for the next transient pre Simulate the grounding reactance and ΔX for this transient is the reactance change step size.

Images