A power grid SFCL configuration method and device

Abstract

The application discloses a power transmission network SFCL configuration method and device, the method comprises the following steps: obtaining the basic data of the power transmission network; according to the basic data, constructing a power transmission network planning model with the minimum SFCL comprehensive configuration cost as the target; and constructing the power transmission network operation constraint and the SFCL operation constraint of the power transmission network planning model based on the basic data; under the constraints of the power transmission network operation constraint and the SFCL operation constraint, solving the power transmission network planning model to generate the configuration type of each SFCL and the configuration position of each SFCL when the SFCL comprehensive configuration cost is minimum; wherein the configuration type of the SFCL comprises resistance type and inductance type; and according to the configuration type of each SFCL and the configuration position of each SFCL, performing SFCL configuration in the power transmission network.

Description

Technical Field

[0001] This invention relates to the field of power transmission network planning technology, and in particular to a method and apparatus for configuring SFCL (Small Private Cloud Classification) in a power transmission network. Background Technology

[0002] With the development of power transmission networks, it is necessary to expand the load capacity of the transmission network to meet future load demands. TCSCs (Thyristor-Controlled Series Capacitors) are widely used in transmission networks to improve the transmission capacity, voltage stability, and ensure flexible operation of the power system. However, when TCSCs are added to existing transmission networks, they reduce transmission impedance, increasing short-circuit currents in existing substations. This can cause short-circuit currents to exceed limits, resulting in short circuits in the transmission network. Current methods to address substation short-circuit problems caused by TCSCs involve upgrading the short-circuit levels of substation components, such as switchgear and transformers. However, this direct upgrade of substation equipment leads to prolonged power outages during the upgrade process.

[0003] SFCL (Superconducting Fault Current Limiter) can quickly exhibit a large impedance under fault conditions to limit short-circuit current, thus effectively suppressing fault current. Configuring SFCL in a transmission network that includes TCSC can eliminate the need for direct upgrades to substation equipment, using SFCL to limit short-circuit problems caused by TCSC. Summary of the Invention

[0004] This invention provides a method and apparatus for configuring SFCL in a power transmission network, which can effectively solve the problem of substations needing to upgrade their short-circuit current due to the introduction of TCSC in the power transmission network. It eliminates the need for direct upgrades and modifications to substation equipment and solves the short-circuit problem caused by TCSC by adding SFCL in the power transmission network.

[0005] An embodiment of the present invention provides a method for configuring SFCL in a power transmission network, comprising:

[0006] Obtain basic data of the power transmission network; wherein, the basic data includes: the cost of adding a resistive SFCL to the power transmission line, the cost of adding an inductive SFCL to the power transmission line, the cost of adding a resistive SFCL to the generator, the cost of adding an inductive SFCL to the generator, the relationship between the generator and the node, the range of node voltage amplitude, the range of generator active power amplitude, the range of generator reactive power amplitude, the dynamic maximum apparent power of each line, the conductance of each line, the susceptance of each line, the range of parallel equivalent conductance generated by the series resistive SFCL of each line, the range of parallel equivalent susceptance generated by the series resistive SFCL of each line, and the upper limit of short-circuit current;

[0007] Based on the aforementioned basic data, a power grid planning model is constructed with the goal of minimizing the overall configuration cost of SFCL; and based on the aforementioned basic data, power grid operation constraints and SFCL operation constraints are constructed for the power grid planning model.

[0008] Under the constraints of power transmission network operation and SFCL operation, the power transmission network planning model is solved to generate the configuration type and location of each SFCL when the overall configuration cost of SFCL is minimized; wherein, the configuration type of SFCL includes: resistive and inductive.

[0009] SFCL configuration is performed in the transmission network according to the configuration type and location of each SFCL.

[0010] Furthermore, the power transmission network planning model is specifically as follows:

[0011]

[0012]

[0013] Where C represents the power transmission network planning model; C I For investment costs; C OP For operating costs; Ω LC A collection of routes; The investment cost of line l; Indicates whether line l participates in the planning process within time t; This indicates whether line l participates in the planning process within time t-1; γ is the investment discount rate. ψ represents the TCSC investment cost when the maximum compensation level of line l is q; l,q,t Indicates whether line l contains a TCSC with a maximum compensation level of q within time t; ψ l,q,t-1 Indicate whether line l contains a TCSC with a maximum compensation level of q within time t-1; The cost of adding a resistive SFCL to the r module on line l; The cost of adding an inductive SFCL to the x module on line l; e l.r.t Indicates whether line l contains a resistive SFCL at time t in module r; e l,r,t-1 Indicates whether line l contains a resistive SFCL in module r at time t-1; f l,x,t Indicates whether line l contains an inductive SFCL at time t in module x; f l,x,t-1 Indicates whether line l contains an inductive SFCL at time x in time t-1; The cost of adding a resistive SFCL to the generator g-module; The cost of adding an inductive SFCL to the x module on generator g; v g,r,t Indicates whether the generator g on module r contains a resistive SFCL; v g,r,t-1 Indicates whether the t-1 time generator g on the r module contains a resistive SFCL; w g,x,t Indicates whether the x module on the time generator g contains an inductive SFCL; w g,x,t-1 Indicates whether the x module on the t-1 time generator g contains an inductive SFCL; Let g be the active power output of generator g under the demand level d at time t; The unit operating cost of generator g; τ d The duration of demand level d; The power loss is given when the demand level is d at time t; ψ l,q,t ψ l,q,t-1 e l.r.t e l,r,t-1 f l,x,t f l,x,t-1 v g,r,t v g,r,t-1 w g,x,t and w g,x,t-1 All values ​​are taken from Boolean values.

[0014] Furthermore, the power grid operation constraints include: basic operation constraints, node power constraints, node voltage constraints, generator operation constraints, and power flow constraints.

[0015] Furthermore, the basic operational constraints are specifically as follows:

[0016]

[0017] ψ l,q,t ≥ψ l,q,t-1 ;

[0018]

[0019] in, Indicates whether line l participates in the planning process within time t; Indicates whether line l participates in the planning process within time t-1; ψ l,q,t Indicates whether line l contains a TCSC with a maximum compensation level of q within time t; ψ l,q,t-1 Indicate whether line l contains a TCSC with a maximum compensation level of q within the time interval t-1.

[0020] Furthermore, the node power constraint is specifically as follows:

[0021]

[0022] in, Let g be the active power output of generator g under the demand level d at time t; Let g be the reactive power output of generator g under the demand level d at time t; This indicates the positional relationship between generator g and node i. The value is 1 when generator g is on node i and 0 when generator g is not on node i. When the time demand level is d, the active power flowing from node i to node j through the existing lines and the lines. When the time demand level is d, the reactive power flowing from node i to node j through the existing lines and the lines. Let d be the active load from node i to node j when the demand level is d at time t. Let d be the reactive load from node i to node j when the demand level is d at time t.

[0023] Furthermore, the node voltage constraint is specifically as follows:

[0024] V i min ≤V i,d,t ≤V i max ;

[0025]

[0026] Among them, V i min V is the lower bound of the voltage magnitude at node i; i max V is the upper bound of the voltage magnitude at node i; i,d,t δ represents the voltage magnitude of node i when the required level is d at time t; i,d,t Let d be the voltage angle of node i when the required level is d at time t.

[0027] Furthermore, the generator operating constraints are specifically as follows:

[0028]

[0029] in, This is the lower bound of the active power amplitude of generator g; This is the upper limit of the active power amplitude of generator g; Let g be the active power amplitude of generator g when the required level is d at time t. This is the lower bound of the reactive power amplitude of generator g; This is the upper limit of the reactive power amplitude of generator g; Let g be the reactive power amplitude of generator g when the required level is d at time t.

[0030] Furthermore, the power flow constraint specifically refers to:

[0031]

[0032] in, When the time demand level is d, the active power flowing from node i to node j through the existing lines and the lines. When the time demand level is d, the reactive power flowing from node i to node j through the existing lines and the lines. The line conductance when the demand level at time t is d during normal operation; V represents the line susceptance when the demand level at time t is d during normal operation; i,d,t V is the voltage at node i when the required level is d at time t; j,d,t Let be the voltage level at node j when the required level is d at time t; δ represents the dynamic maximum apparent power of line ij at time t; ij,d,t Let be the voltage angle of line ij when the required level is d at time t.

[0033] Furthermore, the SFCL operational constraints are specifically as follows:

[0034]

[0035] Among them, e l.r.t Indicates whether line l contains a resistive SFCL at time t in module r; Indicates whether line l participates in the planning process within time t; f l,x,t Indicates whether line l contains an inductive SFCL at time t x; The parallel equivalent conductance generated by the series resistive SFCL of module r on line l; The parallel equivalent susceptance generated by the series resistive SFCL of module r on line l; The parallel equivalent conductance generated by the series inductive SFCL of module x on line l; The parallel equivalent susceptance generated by the series inductive SFCL of module x on line l; This indicates the connection relationship between line l and nodes i and j; To increase the conductivity; To increase the susceptance; Let L be the conductance of line l; The susceptance of line l; The minimum parallel equivalent conductance generated by the TCSC at the maximum compensation level q of line l; The minimum parallel equivalent susceptance generated by the TCSC at the maximum compensation level q of line l; The maximum parallel equivalent conductance generated by the TCSC at the maximum compensation level q of line l; The maximum parallel equivalent susceptance generated by the TCSC at the maximum compensation level q of line l; This refers to the parallel equivalent conductance added to line ij when SFCL is connected in series with line ij; This refers to the parallel equivalent susceptance added to line ij when SFCL is connected in series with line ij; This is due to the parallel equivalent conductance added at node i when the generator is connected in series with the SFCL; This is due to the parallel equivalent susceptance added at node i when the generator is connected in series with the SFCL; The parallel equivalent conductance at generator g is generated by the resistive SFCL of module r. The parallel equivalent conductance at generator g is generated by the inductive SFCL of module x; Let be the short-circuit current of node i when the time requirement level is d at time t. Z for time t BUS The diagonal element i; This is the upper limit of the short-circuit current.

[0036] Based on the above method embodiments, the present invention provides corresponding apparatus embodiments;

[0037] One embodiment of the present invention provides a power transmission network SFCL configuration device, including a data acquisition module, a model and constraint construction module, a model solving module, and a planning module;

[0038] The data acquisition module is used to acquire basic data of the power transmission network. This basic data includes: the cost of adding a resistive SFCL to the transmission line, the cost of adding an inductive SFCL to the transmission line, the cost of adding a resistive SFCL to the generator, the cost of adding an inductive SFCL to the generator, the relationship between the generator and the node location, the node voltage amplitude range, the generator active power amplitude range, the generator reactive power amplitude range, the dynamic maximum apparent power of each line, the conductance of each line, the susceptance of each line, the parallel equivalent conductance range generated by the series resistive SFCLs on each line, the parallel equivalent susceptance range generated by the series resistive SFCLs on each line, and the upper limit of the short-circuit current.

[0039] The model and constraint construction module is used to construct a power transmission network planning model based on the basic data, with the goal of minimizing the comprehensive configuration cost of SFCL; and to construct the power transmission network operation constraints and SFCL operation constraints of the power transmission network planning model based on the basic data.

[0040] The model solving module and planning module are used to solve the transmission network planning model under the constraints of transmission network operation and SFCL operation to generate the configuration type and location of each SFCL when the overall configuration cost of SFCL is minimized; wherein, the configuration type of SFCL includes resistive and inductive types; and SFCLs are configured in the transmission network according to the configuration type and location of each SFCL.

[0041] The following benefits can be obtained by implementing the present invention:

[0042] This invention discloses a method and apparatus for configuring SFCLs in a power transmission network. The method acquires basic data of the power transmission network, constructs a power transmission network planning model with the objective of minimizing the overall configuration cost of SFCLs, and includes corresponding power transmission network operation constraints and SFCL operation constraints. Under these constraints, the model is solved to generate the configuration type and location of each SFCL when the overall configuration cost is minimized. Then, based on the configuration type and location of each SFCL, SFCLs are configured in the power transmission network, resulting in a configured power transmission network containing SFCLs. By adding SFCLs to the power transmission network, the short-circuit problem caused by TCSCs is addressed, resolving the issue of substation short-circuit current upgrades required due to the introduction of TCSCs in the power transmission network. This eliminates the need for direct upgrades to substation equipment and reduces long-term power outages during power transmission network upgrade planning. Furthermore, considering the configuration type of SFCLs during configuration ensures that the configured SFCLs better match the load and power demand of the power transmission network. Attached Figure Description

[0043] Figure 1 This is a flowchart illustrating a power transmission network SFCL configuration method according to an embodiment of the present invention.

[0044] Figure 2 This is a voltage stability margin comparison chart provided by an embodiment of the present invention.

[0045] Figure 3 This is a schematic diagram of the structure of a power transmission network SFCL configuration device provided in an embodiment of the present invention. Detailed Implementation

[0046] 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, and 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.

[0047] like Figure 1 As shown, an embodiment of the present invention provides a method for configuring SFCL in a power transmission network, including:

[0048] Step S1: Obtain basic data of the power transmission network; wherein, the basic data includes: the cost of adding a resistive SFCL to the transmission line, the cost of adding an inductive SFCL to the transmission line, the cost of adding a resistive SFCL to the generator, the cost of adding an inductive SFCL to the generator, the relationship between the generator and the node, the range of node voltage amplitude, the range of generator active power amplitude, the range of generator reactive power amplitude, the dynamic maximum apparent power of each line, the conductance of each line, the susceptance of each line, the range of parallel equivalent conductance generated by the series resistive SFCL of each line, the range of parallel equivalent susceptance generated by the series resistive SFCL of each line, and the upper limit of short-circuit current;

[0049] Step S2: Based on the basic data, construct a power transmission network planning model with the goal of minimizing the overall configuration cost of SFCL; and construct the power transmission network operation constraints and SFCL operation constraints of the power transmission network planning model based on the basic data.

[0050] Step S3: Under the constraints of power transmission network operation and SFCL operation, solve the power transmission network planning model to generate the configuration type and configuration location of each SFCL when the comprehensive configuration cost of SFCL is minimized; wherein, the configuration type of SFCL includes: resistive and inductive.

[0051] Step S4: Configure SFCLs in the transmission network according to the configuration type and location of each SFCL.

[0052] For step S1, obtain the basic data of the transmission network, including the cost of adding a resistive SFCL to the transmission line, the cost of adding an inductive SFCL to the transmission line, the cost of adding a resistive SFCL to the generator, the cost of adding an inductive SFCL to the generator, the relationship between the generator and the node, the range of node voltage amplitude, the range of generator active power amplitude, the range of generator reactive power amplitude, the dynamic maximum apparent power of each line, the conductance of each line, the susceptance of each line, the range of parallel equivalent conductance generated by the series resistive SFCL of each line, the range of parallel equivalent susceptance generated by the series resistive SFCL of each line, and the upper limit of short-circuit current.

[0053] For step S2, based on the basic data obtained in step S1, with the goal of minimizing the comprehensive configuration cost of SFCL, that is, minimizing the comprehensive investment cost and operating cost of the transmission network after adding SFCL, a transmission network planning model is constructed, along with the corresponding transmission network operation constraints and SFCL operation constraints.

[0054] In a preferred embodiment, the power transmission network planning model is specifically as follows:

[0055]

[0056] Where C represents the power transmission network planning model; C I For investment costs; C OP For operating costs; Ω LC A collection of routes; The investment cost of line l; Indicates whether line l participates in the planning process within time t; This indicates whether line l participates in the planning process within time t-1; γ is the investment discount rate. ψ represents the TCSC investment cost when the maximum compensation level of line l is q; l,q,t Indicates whether line l contains a TCSC with a maximum compensation level of q within time t; ψ l,q,t-1 Indicate whether line l contains a TCSC with a maximum compensation level of q within time t-1; The cost of adding a resistive SFCL to the r module on line l; The cost of adding an inductive SFCL to the x module on line l; e l.r.t Indicates whether line l contains a resistive SFCL at time t in module r; e l,r,t-1 Indicates whether line l contains a resistive SFCL in module r at time t-1; f l,x,t Indicates whether line l contains an inductive SFCL at time t in module x; f l,x,t-1 Indicates whether line l contains an inductive SFCL at time x in time t-1; The cost of adding a resistive SFCL to the generator g-module; The cost of adding an inductive SFCL to the x module on generator g; v g,r,t Indicates whether the generator g on module r contains a resistive SFCL; v g,r,t-1 Indicates whether the t-1 time generator g on the r module contains a resistive SFCL; w g,x,t Indicates whether the x module on the time generator g contains an inductive SFCL; w g,x,t-1 Indicates whether the x module on the t-1 time generator g contains an inductive SFCL; Let g be the active power output of generator g under the demand level d at time t; The unit operating cost of generator g; τ d The duration of demand level d; The power loss is given when the demand level is d at time t; ψ l,q,t ψ l,q,t-1 e l.r.t e l,r,t-1 f l,x,t f l,x,t-1 v g,r,t v g,r,t-1 w g,x,t and w g,x,t-1 All values ​​are taken from Boolean values.

[0057] It should be noted that in the above power transmission network planning model, ψ l,q,t ψ l,q,t-1 e l.r.t e l,r,t-1 f l,x,t f l,x,t-1 v g,r,t v g,r,t-1 w g,x,t and w g,x,t-1 All values ​​are Boolean; if line l did not participate in the planning at time t, The value is then 0 if line l participates in the planning at time t. Then the value is 1; if line l contains a TCSC with a maximum compensation level of q within time t, ψ l,q,t The value is 1; if line l does not contain a TCSC with a maximum compensation level of q within time t, ψ l,q,t The value is 0; line l contains a resistive SFCL in module r at time t, e l.r.t The value is 1; line l does not contain resistive SFCL in module r at time t, e l.r.t The value is 0; line l contains an inductive SFCL in module x at time t, fl,x,t The value is 1; line l does not contain an inductive SFCL in module x at time t, f l,x,t The value is 0; the time generator g on the r module contains a resistive SFCL, v g,r,t The value is 1; the t-time generator g module does not contain a resistive SFCL, v g,r,t The value is 0; the x module on the time generator g contains an inductive SFCL, w g,x,t The value is 1; the x module on the time generator g does not contain an inductive SFCL, w g,x,t The value is 0. Furthermore, γ、 These cost and expense related parameters are constants, for example... Let g be the unit operating cost of generator g. For each generator, the operating cost per unit of power generation is a constant, and this objective constant is used as the value in the calculation. The above-mentioned lines all refer to lines that can be considered as candidate lines for planning during the transmission network planning process.

[0058] In a preferred embodiment, the power grid operation constraints include: basic operation constraints, node power constraints, node voltage constraints, generator operation constraints, and power flow constraints.

[0059] Specifically, transmission network operation constraints mainly refer to the operation constraints of the transmission network when no new SFCLs are added, but only new lines and TCSCs are added.

[0060] In a preferred embodiment, the basic operational constraints are specifically:

[0061]

[0062] ψ l,q,t ≥ψ l,q,t-1 (5)

[0063]

[0064] in, Indicates whether line l participates in the planning process within time t; Indicates whether line l participates in the planning process within time t-1; ψ l,q,t Indicates whether line l contains a TCSC with a maximum compensation level of q within time t; ψ l,q,t-1 Indicate whether line l contains a TCSC with a maximum compensation level of q within the time interval t-1.

[0065] Specifically, if a new line or TCSC is configured within a time period, the constraints of formulas (4) and (5) above can ensure that the newly added line and TCSC in subsequent event segments are also available in subsequent time periods. Formula (6) above indicates that TCSC is installed only on the selected line, which ensures that only a specific TCSC compensation level is selected in each time interval.

[0066] In a preferred embodiment, the node power constraint specifically includes:

[0067]

[0068] in, Let g be the active power output of generator g under the demand level d at time t; Let g be the reactive power output of generator g under the demand level d at time t; This indicates the positional relationship between generator g and node i. The value is 1 when generator g is on node i and 0 when generator g is not on node i. When the time demand level is d, the active power flowing from node i to node j through the existing lines and the lines. When the time demand level is d, the reactive power flowing from node i to node j through the existing lines and the lines. Let d be the active load from node i to node j when the demand level is d at time t. Let d be the reactive load from node i to node j when the demand level is d at time t.

[0069] Specifically, formula (7) represents the active power balance constraint of each node, and formula (8) represents the reactive power balance constraint of each node.

[0070] In a preferred embodiment, the node voltage constraint specifically includes:

[0071] V i min ≤V i,d,t ≤V i max (9)

[0072]

[0073] Among them, V i min V is the lower bound of the voltage magnitude at node i; i max V is the upper bound of the voltage magnitude at node i; i,d,t δ represents the voltage magnitude of node i when the required level is d at time t; i,d,t Let d be the voltage angle of node i when the required level is d at time t.

[0074] In a preferred embodiment, the generator operating constraints are specifically:

[0075]

[0076] in, This is the lower bound of the active power amplitude of generator g; This is the upper limit of the active power amplitude of generator g; Let g be the active power amplitude of generator g when the required level is d at time t. This is the lower bound of the reactive power amplitude of generator g; This is the upper limit of the reactive power amplitude of generator g; Let g be the reactive power amplitude of generator g when the required level is d at time t.

[0077] In a preferred embodiment, the power flow constraint specifically includes:

[0078]

[0079] in, When the time demand level is d, the active power flowing from node i to node j through the existing lines and the lines. When the time demand level is d, the reactive power flowing from node i to node j through the existing lines and the lines. The line conductance when the demand level at time t is d during normal operation; V represents the line susceptance when the demand level at time t is d during normal operation; i,d,t V is the voltage at node i when the required level is d at time t; j,d,t Let be the voltage level at node j when the required level is d at time t; δ represents the dynamic maximum apparent power of line ij at time t; ij,d,t Let be the voltage angle of line ij when the required level is d at time t.

[0080] In a preferred embodiment, the SFCL operating constraints are specifically:

[0081]

[0082] Among them, e l.r.t Indicates whether line l contains a resistive SFCL at time t in module r; Indicates whether line l participates in the planning process within time t; f l,x,t Indicates whether line l contains an inductive SFCL at time t x; The parallel equivalent conductance generated by the series resistive SFCL of module r on line l; The parallel equivalent susceptance generated by the series resistive SFCL of module r on line l; The parallel equivalent conductance generated by the series inductive SFCL of module x on line l; The parallel equivalent susceptance generated by the series inductive SFCL of module x on line l; This represents the connection relationship between line l and nodes i and j, and is a Boolean value. If line l connects both nodes i and j, then... The value is 1. If line l does not simultaneously connect nodes i and j, then The value is 0; To increase the conductivity; To increase the susceptance; Let L be the conductance of line l; The susceptance of line l; The minimum parallel equivalent conductance generated by the TCSC at the maximum compensation level q of line l; The minimum parallel equivalent susceptance generated by the TCSC at the maximum compensation level q of line l; The maximum parallel equivalent conductance generated by the TCSC at the maximum compensation level q of line l; The maximum parallel equivalent susceptance generated by the TCSC at the maximum compensation level q of line l; This refers to the parallel equivalent conductance added to line ij when SFCL is connected in series with line ij; This refers to the parallel equivalent susceptance added to line ij when SFCL is connected in series with line ij; This is due to the parallel equivalent conductance added at node i when the generator is connected in series with the SFCL; This is due to the parallel equivalent susceptance added at node i when the generator is connected in series with the SFCL; The parallel equivalent conductance at generator g is generated by the resistive SFCL of module r. The parallel equivalent conductance at generator g is generated by the inductive SFCL of module x; Let be the short-circuit current of node i when the time requirement level is d at time t. Z for time t BUS The diagonal element i; This is the upper limit of the short-circuit current.

[0083] Specifically, equations (16) and (17) represent the constraints required to allow the installation of resistive and inductive SFCLs in selected lines. Equations (18) and (19) represent the equivalent parallel admittance to line ij increased due to the line SFCL. Equations (20) and (21) represent the transmission line admittance increments due to the addition of new lines, TCSCs, and SFCLs. Equations (22) and (23) represent the effect of generator SFCLs on node self-admittance. Equation (24) represents the effect of the updated Z... BUS The short-circuit current of all nodes in the transmission network calculated by the diagonal elements must satisfy the constraint that it is less than the upper limit of the short-circuit current, so as to achieve the desired effect of the present invention.

[0084] Regarding the transmission network impedance matrix, it should be noted that the network impedance matrix will change after adding new lines, TCSCs, and SFCLs. In this case, it is necessary to calculate the change in the network impedance matrix. This is because this invention connects the TCSC / SFCL in series with existing / new lines, increasing the line-related components and altering the original Z-axis impedance. BUS Diagonal elements can be transformed into their parallel equivalent admittances. Specifically, in Z... BUS Add a line to the existing line mn on the diagonal element. Then increase After Z BUS The change in diagonal element i for:

[0085]

[0086] in, This represents the diagonal element values ​​of the original impedance matrix at node m; This represents the diagonal element values ​​of the original impedance matrix at node n; To increase After Z BUS The amount of change in the diagonal element i; the superscript L indicates a change due to the addition of line-related components; This indicates that the line has added the SFCL component; Z represents BUS The primitive elements ij (in bold, indicating complex numbers); Let be the branch impedance between nodes m and n. Define a constant. and Then, summing the parallel admittances of all added components, Z is calculated. BUS The change of the diagonal element i is:

[0087]

[0088] In this equation, the superscript PLS indicates the line series SFCL; the superscript PT indicates the effect of TCSC on the line. In fact, all changes resulting from the addition of new components are incorporated into the above equation and apply only to the original Z. BUS The element is quantized once. This one-step Z-formation... BUS Updating, rather than repeatedly updating, reduces the number of constraints in the optimization problem. The above equation can be rewritten using the real and imaginary parts as follows:

[0089]

[0090] in, Its components represent the total parallel conductance and susceptance of the new components.

[0091] The network impedance changes after adding the generator SFCL are as follows:

[0092] The impedance at node m is The series-connected generator SFCL can be expressed as the equivalent parallel admittance. As shown in the following formula:

[0093]

[0094] in, The generator impedance; Z represents BUS The diagonal element i due to The amount of change that occurs.

[0095] By defining constants and Formula (29) can be simplified to:

[0096]

[0097] Among them, C i,m and D m It can be derived from the original Z BUS The calculation yields the following result. Rewriting the complex quantity in the above equation using the real and imaginary parts, we get:

[0098]

[0099] Based on the above Z BUS Based on the theory of diagonal element changes, using formulas (27) and (31), it can be seen that after adding new components to the transmission network, namely new lines, TCSCs, and SFCLs, Z BUS The diagonal element i changes as follows:

[0100]

[0101]

[0102] Using the updated Z BUS Diagonal element, i.e., Z at time t BUS The diagonal element i and the voltage of node i when the time demand level is d can be used to calculate the short-circuit current of node i when the time demand level is d. Then, the short-circuit current of all nodes in the transmission network can be obtained. Combined with formula (24), it can be determined whether the calculated short-circuit current meets the constraints.

[0103] For step S3, solving the transmission network planning model under all the above constraints, this invention proposes an improved Benders algorithm to solve the transmission network planning model. First, the nonlinear constraints corresponding to the model are linearized.

[0104] Power flow equations are variables The nonlinear function, the equation for the change of the impedance matrix is These are nonlinear functions. Using a first-order Taylor series expansion, these nonlinear functions are linearized around the base point X0 as follows:

[0105]

[0106] Among them, X 1,0 X 2,0 X1 and X2 are the values ​​at the base point X0, respectively; the superscript LN indicates the linearized value of the nonlinear function.

[0107] The results of quadratic constraint linearization are as follows:

[0108]

[0109] Among them, a k ,b k ,c k It is a constant that defines the slope and position of line k. The region a enclosed by these lines... k x+b k y≤c k The intersection of r is approximately equal to the area of ​​a circle, which can be approximated by defining several lines of a polygon inside the circle at equally spaced points.

[0110] Similarly, the nonlinear equation (9) can be rewritten as the following linear equation:

[0111]

[0112] Furthermore, this invention proposes a Benders decomposition scheme to minimize the linearization error of the aforementioned problem. The principal problem (MP) of the decomposition scheme is determined; this MP is a small MILP problem for determining the investment decisions of the power grid. The power grid planning model and its corresponding constraints are transformed, yielding the following results:

[0113]

[0114] st(2),(4)-(6),(16)-(17)

[0115] Where st represents the constraint that needs to be satisfied, and the number following it is the corresponding formula.

[0116] Subproblem 1 (SP1) of the Benders decomposition scheme is proposed. SP1 is an LP problem, as follows:

[0117]

[0118] st(3),(9)-(12),(16)-(23),(32),(35)-(38)

[0119] Where Y is a vector of binary variables whose values ​​are obtained from MP; λ SP1 It is the dual value.

[0120] Furthermore, subproblem 2 (SP2) of the Benders decomposition scheme is proposed. SP2 involves nonlinear functions and is an NLP problem, as shown below:

[0121]

[0122]

[0123] st(3),(13)-(14),(33)-(34),(35)-(40)

[0124] Where, λ SP2 It is the dual value.

[0125] Finally, based on the defined problem, the solvers Gurobi and Conopt are invoked to solve it, and the configuration type and configuration location of each SFCL are obtained when the overall configuration cost of the SFCL is minimized.

[0126] For step S4, determine the location and type of SFCL to be configured in the transmission network based on the configuration type and location of each SFCL, thereby reducing the cost of SFCL configuration while ensuring that the short-circuit current problem caused by TCSC is solved.

[0127] Preferred, such as Figure 2 The diagram shows a comparison of the voltage stability margin between the existing power transmission network planning scheme (traditional TEP) and the power transmission network planning scheme proposed in this invention (proposed TEP). It can be seen that the scheme proposed in this invention has better performance.

[0128] Based on the above method embodiments, the present invention provides corresponding apparatus embodiments.

[0129] like Figure 3 As shown, an embodiment of the present invention provides a power transmission network SFCL configuration device, including a data acquisition module, a model and constraint construction module, a model solving module, and a planning module;

[0130] The data acquisition module is used to acquire basic data of the power transmission network. This basic data includes: the cost of adding a resistive SFCL to the transmission line, the cost of adding an inductive SFCL to the transmission line, the cost of adding a resistive SFCL to the generator, the cost of adding an inductive SFCL to the generator, the relationship between the generator and the node location, the node voltage amplitude range, the generator active power amplitude range, the generator reactive power amplitude range, the dynamic maximum apparent power of each line, the conductance of each line, the susceptance of each line, the parallel equivalent conductance range generated by the series resistive SFCLs on each line, the parallel equivalent susceptance range generated by the series resistive SFCLs on each line, and the upper limit of the short-circuit current.

[0131] The model and constraint construction module is used to construct a power transmission network planning model based on the basic data, with the goal of minimizing the comprehensive configuration cost of SFCL; and to construct the power transmission network operation constraints and SFCL operation constraints of the power transmission network planning model based on the basic data.

[0132] The model solving module and planning module are used to solve the transmission network planning model under the constraints of transmission network operation and SFCL operation to generate the configuration type and location of each SFCL when the overall configuration cost of SFCL is minimized; wherein, the configuration type of SFCL includes resistive and inductive types; and SFCLs are configured in the transmission network according to the configuration type and location of each SFCL.

[0133] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Furthermore, in the accompanying drawings of the device embodiments provided by this invention, the connection relationships between modules indicate that they have communication connections, which can be specifically implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement this without any creative effort.

[0134] Those skilled in the art will clearly understand that, for convenience and brevity, the specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0135] The terminal device can be a desktop computer, laptop, handheld computer, or cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0136] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the terminal device, connecting all parts of the terminal device via various interfaces and lines.

[0137] The memory can be used to store the computer program. The processor implements various functions of the terminal device by running or executing the computer program stored in the memory and calling data stored in the memory. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function, etc.; the data storage area may store data created based on the use of the mobile phone, etc. In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, RAM, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0138] The storage medium is a computer-readable storage medium, and the computer program is stored in the computer-readable storage medium. When executed by a processor, the computer program can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0139] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for configuring SFCL in a power transmission network, characterized in that, include: Obtain basic data of the power transmission network; wherein, the basic data includes: the cost of adding a resistive SFCL to the power transmission line, the cost of adding an inductive SFCL to the power transmission line, the cost of adding a resistive SFCL to the generator, the cost of adding an inductive SFCL to the generator, the relationship between the generator and the node, the range of node voltage amplitude, the range of generator active power amplitude, the range of generator reactive power amplitude, the dynamic maximum apparent power of each line, the conductance of each line, the susceptance of each line, the range of parallel equivalent conductance generated by the series resistive SFCL of each line, the range of parallel equivalent susceptance generated by the series resistive SFCL of each line, and the upper limit of short-circuit current; Based on the aforementioned basic data, a power grid planning model is constructed with the goal of minimizing the overall configuration cost of SFCL; and based on the aforementioned basic data, power grid operation constraints and SFCL operation constraints are constructed for the power grid planning model. Under the constraints of power transmission network operation and SFCL operation, the power transmission network planning model is solved to generate the configuration type and location of each SFCL when the overall configuration cost of SFCL is minimized; wherein, the configuration type of SFCL includes: resistive and inductive. SFCL configuration is performed in the transmission network according to the configuration type and location of each SFCL.

2. The SFCL configuration method for a power transmission network as described in claim 1, characterized in that, The power transmission network planning model is as follows: Where C represents the power transmission network planning model; C I For investment costs; C OP For operating costs; Ω LC A collection of routes; The investment cost of line l; Indicates whether line l participates in the planning process within time t; This indicates whether line l participates in the planning process within time t-1; γ is the investment discount rate. ψ represents the TCSC investment cost when the maximum compensation level of line l is q; l,q,t Indicates whether line l contains a TCSC with a maximum compensation level of q within time t; ψ l,q,t-1 Indicate whether line l contains a TCSC with a maximum compensation level of q within time t-1; The cost of adding a resistive SFCL to the r module on line l; The cost of adding an inductive SFCL to the x module on line l; e l.r.t Indicates whether line l contains a resistive SFCL at time t in module r; e l,r,t-1 Indicates whether line l contains a resistive SFCL in module r at time t-1; f l,x,t Indicates whether line l contains an inductive SFCL at time t in module x; f l,x,t-1 Indicates whether line l contains an inductive SFCL at time x in time t-1; The cost of adding a resistive SFCL to the generator g-module; The cost of adding an inductive SFCL to the x module on generator g; v g,r,t Indicates whether the generator g on module r contains a resistive SFCL; v g,r,t-1 Indicates whether the t-1 time generator g on the r module contains a resistive SFCL; w g,x,t Indicates whether the x module on the time generator g contains an inductive SFCL; w g,x,t-1 Indicates whether the x module on the t-1 time generator g contains an inductive SFCL; Let g be the active power output of generator g under the demand level d at time t; The unit operating cost of generator g; τ d The duration of demand level d; The power loss is given when the demand level is d at time t; ψ l,q,t ψ l,q,t-1 e l.r.t e l,r,t-1 f l,x,t f l,x,t-1 v g,r,t v g,r,t-1 w g,x,t and w g,x,t-1 All values ​​are taken from Boolean values.

3. The SFCL configuration method for a power transmission network as described in claim 2, characterized in that, The power grid operation constraints include: basic operation constraints, node power constraints, node voltage constraints, generator operation constraints, and power flow constraints.

4. The SFCL configuration method for a power transmission network as described in claim 3, characterized in that, The basic operational constraints are as follows: ψ l,q,t ≥ψ l,q,t-1 ; in, Indicates whether line l participates in the planning process within time t; Indicates whether line l participates in the planning process within time t-1; ψ l,q,t Indicates whether line l contains a TCSC with a maximum compensation level of q within time t; ψ l,q,t-1 Indicate whether line l contains a TCSC with a maximum compensation level of q within the time interval t-1.

5. The SFCL configuration method for a power transmission network as described in claim 4, characterized in that, The node power constraint is specifically as follows: in, Let g be the active power output of generator g under the demand level d at time t; Let g be the reactive power output of generator g under the demand level d at time t; This indicates the positional relationship between generator g and node i. The value is 1 when generator g is on node i and 0 when generator g is not on node i. When the time demand level is d, the active power flowing from node i to node j through the existing lines and the lines. When the time demand level is d, the reactive power flowing from node i to node j through the existing lines and the lines. Let d be the active load from node i to node j when the demand level is d at time t. Let d be the reactive load from node i to node j when the demand level is d at time t.

6. The SFCL configuration method for a power transmission network as described in claim 5, characterized in that, The node voltage constraint is specifically as follows: in, This is the lower bound of the voltage magnitude at node i; V is the upper bound of the voltage magnitude at node i; i,d,t δ represents the voltage magnitude of node i when the required level is d at time t; i,d,t Let d be the voltage angle of node i when the required level is d at time t.

7. The SFCL configuration method for a power transmission network as described in claim 6, characterized in that, The generator operating constraints are as follows: in, This is the lower bound of the active power amplitude of generator g; This is the upper limit of the active power amplitude of generator g; Let g be the active power amplitude of generator g when the required level is d at time t. This is the lower bound of the reactive power amplitude of generator g; This is the upper limit of the reactive power amplitude of generator g; Let g be the reactive power amplitude of generator g when the required level is d at time t.

8. The SFCL configuration method for a power transmission network as described in claim 7, characterized in that, The power flow constraints are specifically as follows: in, When the time demand level is d, the active power flowing from node i to node j through the existing lines and the lines. When the time demand level is d, the reactive power flowing from node i to node j through the existing lines and the lines. The line conductance when the demand level at time t is d during normal operation; V represents the line susceptance when the demand level at time t is d during normal operation; i,d,t V is the voltage at node i when the required level is d at time t; j,d,t Let be the voltage level at node j when the required level is d at time t; δ represents the dynamic maximum apparent power of line ij at time t; ij,d,t Let be the voltage angle of line ij when the required level is d at time t.

9. The SFCL configuration method for a power transmission network as described in claim 8, characterized in that, The specific SFCL operating constraints are as follows: Among them, e l.r.t Indicates whether line l contains a resistive SFCL at time t in module r; Indicates whether line l participates in the planning process within time t; f l,x,t Indicates whether line l contains an inductive SFCL at time t x; The parallel equivalent conductance generated by the series resistive SFCL of module r on line l; The parallel equivalent susceptance generated by the series resistive SFCL of module r on line l; The parallel equivalent conductance generated by the series inductive SFCL of module x on line l; The parallel equivalent susceptance generated by the series inductive SFCL of module x on line l; This indicates the connection relationship between line l and nodes i and j; To increase the conductivity; To increase the susceptance; Let L be the conductance of line l; The susceptance of line l; The minimum parallel equivalent conductance generated by the TCSC at the maximum compensation level q of line l; The minimum parallel equivalent susceptance generated by the TCSC at the maximum compensation level q of line l; The maximum parallel equivalent conductance generated by the TCSC at the maximum compensation level q of line l; The maximum parallel equivalent susceptance generated by the TCSC at the maximum compensation level q of line l; This refers to the parallel equivalent conductance added to line ij when SFCL is connected in series with line ij; This refers to the parallel equivalent susceptance added to line ij when SFCL is connected in series with line ij; This is due to the parallel equivalent conductance added at node i when the generator is connected in series with the SFCL; This is due to the parallel equivalent susceptance added at node i when the generator is connected in series with the SFCL; The parallel equivalent conductance at generator g is generated by the resistive SFCL of module r. The parallel equivalent conductance at generator g is generated by the inductive SFCL of module x; Let be the short-circuit current of node i when the time requirement level is d at time t. Z for time t BUS The diagonal element i; This is the upper limit of the short-circuit current.

10. A power transmission network SFCL configuration device, characterized in that, include: The module includes a data acquisition module, a model and constraint construction module, a model solving module, and a planning module. The data acquisition module is used to acquire basic data of the power transmission network. This basic data includes: the cost of adding a resistive SFCL to the transmission line, the cost of adding an inductive SFCL to the transmission line, the cost of adding a resistive SFCL to the generator, the cost of adding an inductive SFCL to the generator, the relationship between the generator and the node location, the node voltage amplitude range, the generator active power amplitude range, the generator reactive power amplitude range, the dynamic maximum apparent power of each line, the conductance of each line, the susceptance of each line, the parallel equivalent conductance range generated by the series resistive SFCLs on each line, the parallel equivalent susceptance range generated by the series resistive SFCLs on each line, and the upper limit of the short-circuit current. The model and constraint construction module is used to construct a power transmission network planning model based on the basic data, with the goal of minimizing the comprehensive configuration cost of SFCL; and to construct the power transmission network operation constraints and SFCL operation constraints of the power transmission network planning model based on the basic data. The model solving module and planning module are used to solve the transmission network planning model under the constraints of transmission network operation and SFCL operation to generate the configuration type and location of each SFCL when the overall configuration cost of SFCL is minimized; wherein, the configuration type of SFCL includes resistive and inductive types; and SFCLs are configured in the transmission network according to the configuration type and location of each SFCL.

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