Rotary power flow controller power control method, device, equipment and medium

Abstract

The invention relates to a rotating power flow controller power control method, device and equipment and a medium, and the method comprises the steps: taking a power distribution network bearing capacity index as a target, taking a power flow constraint, a node voltage constraint and a line current-carrying capacity constraint as constraint conditions, and constructing a rotating power flow controller power optimization model; solving the power optimization model of the rotary power flow controller to obtain an optimal power value of the rotary power flow controller; obtaining a rotation angle reference value of the rotation power flow controller based on the optimal power value of the rotation power flow controller; and taking the rotation angle of the rotation power flow controller as the control target of the controller, taking the rotation angle reference value as the input of the controller, obtaining a power control instruction, and completing the power control of the rotation power flow controller by adopting the power control instruction. The bearing capacity of the power distribution network and the accuracy of power control can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power distribution network and distributed power supply grid connection, and in particular to a power control method, device, equipment and medium of a rotating power flow controller. Background Art

[0002] As the final link of the power system facing users, the distribution network is a key part to ensure urban industrial production and residents' daily life. The carrying capacity and stability of the active distribution network are crucial to ensure power supply reliability. At present, most distribution substations adopt the power supply mode of "closed-loop design and open-loop operation". With the high proportion of access to various sources and loads such as new energy power generation and electric vehicles, the distribution substations are facing problems such as insufficient carrying capacity such as reverse flow and voltage over-limit. In addition, the traditional distribution substation has a weak grid structure, a fixed adjustment method, and a lack of sufficient flexible adjustment capabilities, making it more difficult to regulate voltage and flow.

[0003] In recent years, the emergence of different types of flexible interconnection devices (FIDs) has provided an effective solution to the problem of interconnection between substations. The flexible transformation of the distribution network using flexible interconnection devices can greatly improve the flexibility and safety of distribution network control. By interconnecting and supplying multiple substations through FIDs, the excess renewable energy power in the substation area can be transferred to another heavy-load substation area, which can effectively improve the carrying capacity of the distribution network while reducing the network loss in the distribution substation area.

[0004] Rotary Power Flow Controller (RPFC) is an electromagnetic flexible AC interconnected distribution device. It controls the line flow by changing the rotor angle of phase synthesis and adjusting the voltage and phase of the RPFC injected into the line. As a continuously adjustable flow control device, it can flexibly compensate the line voltage and accurately achieve the goal of flow control. It has the advantages of fast response speed, high reliability, simple control, low cost and strong fault tolerance. It can be seen that RPFC has broad application prospects in distribution network flow control and improving the carrying capacity of distribution network.

[0005] At present, the power control method of RPFC is mostly to regulate active and reactive power according to the set control target values. However, these control target values ​​are usually set based on manual experience and lack accurate calculation and scientific guidance. In addition, the control targets set according to static experience values ​​may not be able to effectively respond to changes in the load characteristics and operating characteristics of the power system, resulting in a decrease in control effect when the load fluctuates or the network structure changes, and cannot enhance the carrying capacity of the distribution network. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a power control method, device, equipment and medium for a rotating power flow controller, which can improve the carrying capacity of a distribution network and the accuracy of power control.

[0007] The technical solution adopted by the present invention to solve the technical problem is: to provide a power control method of a rotating power flow controller, comprising the following steps:

[0008] Taking the distribution network carrying capacity index as the target, and taking the power flow constraint, node voltage constraint, and line current carrying capacity constraint as the constraint conditions, a power optimization model of the rotating power flow controller is constructed.

[0009] Solving the power optimization model of the rotating power flow controller to obtain the optimal power value of the rotating power flow controller;

[0010] Obtaining a rotation angle reference value of the rotating power flow controller based on the optimal power value of the rotating power flow controller;

[0011] The rotation angle of the rotating power flow controller is used as the control target of the controller, the rotation angle reference value is used as the controller input, a power control instruction is obtained, and the power control of the rotating power flow controller is completed by using the power control instruction.

[0012] The objective function of the power optimization model of the rotating power flow controller is expressed as: F1 = αF M +βF L , where F1 is the carrying capacity of the distribution network, F M is the power flow balance, expressed as: F L is the line capacity margin, expressed as: α and β are weight coefficients, and α+β=1,0≤α≤1,0≤β≤1, S M,1,t and S M,2,t are the apparent powers flowing through the main transformers of the two flexible interconnected lines at time t; S max,1 and S max,2 are the rated apparent powers of the main transformers of the two flexible interconnected lines respectively; T is the number of time periods; N is the total number of branches of the two flexible interconnected lines; I ij,n,t is the branch current flowing through the nth line at time t; I max,n is the rated current of the nth circuit.

[0013] The constraints of the power optimization model of the rotating power flow controller are expressed as: Among them, V i and V j are the voltages at nodes i and j, respectively, and r ij is the resistance of branch ij, x ij is the reactance of branch ij, P ijis the active power flowing through branch ij, Q ij is the reactive power flowing through branch ij, k is the end node of the branch with node j as the first node, P L,j represents the active power of the load at node j, P DG,j represents the active power of the distributed generation at node j, P RPFC.j is the active power flowing through the rotating power flow controller at node j; Q L,j is the reactive power of the load at node j; Q RPFC.j is the reactive power flowing through the rotating power flow controller at node j, S ij,max is the maximum apparent power allowed to pass through line ij.

[0014] The step of obtaining a rotation angle reference value of the rotating power flow controller based on the optimal power value of the rotating power flow controller specifically includes:

[0015] Inputting the optimal power value of the rotating power flow controller into the controller as a set value to obtain the actual active power value and reactive power value of the rotating power flow controller;

[0016] Perform dq decomposition on the three-phase voltage at the R end and the three-phase voltage at the G end of the line to which the rotating power flow controller is connected, and obtain the direct-axis voltage at the G end, the direct-axis voltage at the R end, and the quadrature-axis voltage at the R end of the rotating power flow controller;

[0017] Calculate the d-axis voltage and q-axis voltage of the rotating power flow controller according to the actual active power value, reactive power value, the direct-axis voltage at the G end, the direct-axis voltage at the R end, the quadrature-axis voltage at the R end of the rotating power flow controller, and the impedance of the rotating power flow controller connected in series with the line;

[0018] According to the d-axis voltage and q-axis voltage of the rotating power flow controller, the voltage amplitude and voltage angle of the line connected in series with the rotating power flow controller are obtained;

[0019] A rotation angle reference value of the rotating power flow controller is obtained based on the voltage amplitude and voltage angle of the line connected in series with the rotating power flow controller.

[0020] The d-axis voltage and q-axis voltage of the rotating power flow controller are Calculated, where U RPFCd and U RPFCq are the d-axis voltage and q-axis voltage of the rotating power flow controller, U Gd is the direct-axis voltage at the G end of the rotary power flow controller, U Rd is the direct-axis voltage at the R terminal of the rotary power flow controller, U Rq is the quadrature-axis voltage at the R end of the rotating power flow controller, P and Q are the actual active power value and reactive power value of the rotating power flow controller, R and L are the resistance and inductance of the rotating power flow controller, and ω is the angular frequency.

[0021] The technical solution adopted by the present invention to solve the technical problem is: to provide a power control device of a rotating power flow controller, comprising:

[0022] A construction module is used to construct a power optimization model of a rotating power flow controller with the distribution network carrying capacity index as the target and the power flow constraint, node voltage constraint, and line current carrying capacity constraint as the constraint conditions;

[0023] A solution module, used for solving the power optimization model of the rotating power flow controller to obtain the optimal power value of the rotating power flow controller;

[0024] A calculation module, used for obtaining a rotation angle reference value of the rotating power flow controller based on the optimal power value of the rotating power flow controller;

[0025] The control module is used to use the rotation angle of the rotating power flow controller as the control target of the controller, use the rotation angle reference value as the controller input, obtain the power control instruction, and use the power control instruction to complete the power control of the rotating power flow controller.

[0026] The objective function of the power optimization model of the rotating power flow controller constructed by the building module is expressed as: F1 = αF M +βF L , where F1 is the carrying capacity of the distribution network, F M is the power flow balance, expressed as: F L is the line capacity margin, expressed as: α and β are weight coefficients, and α+β=1,0≤α≤1,0≤β≤1, S M,1,t and S M,2,t are the apparent powers flowing through the main transformers of the two flexible interconnected lines at time t; S max,1 and S max,2 are the rated apparent powers of the main transformers of the two flexible interconnected lines respectively; T is the number of time periods; N is the total number of branches of the two flexible interconnected lines; I ij,n,t is the branch current flowing through the nth line at time t; I max,n is the rated current of the nth line.

[0027] The constraints of the power optimization model of the rotating power flow controller constructed by the building module are expressed as follows: Among them, V i and V j are the voltages at nodes i and j, respectively, and r ij is the resistance of branch ij, x ij is the reactance of branch ij, P ij is the active power flowing through branch ij, Q ijis the reactive power flowing through branch ij, k is the end node of the branch with node j as the first node, P L,j represents the active power of the load at node j, P DG,j represents the active power of the distributed generation at node j, P RPFC.j is the active power flowing through the rotating power flow controller at node j; Q L,j is the reactive power of the load at node j; Q RPFC.j is the reactive power flowing through the rotating power flow controller at node j, S ij,max is the maximum apparent power allowed to pass through line ij.

[0028] The calculation module comprises:

[0029] A power value calculation unit, used to input the optimal power value of the rotating power flow controller as a set value into the controller to obtain the actual active power value and reactive power value of the rotating power flow controller;

[0030] A decomposition unit is used to perform dq decomposition on the three-phase voltage at the R end and the three-phase voltage at the G end of the rotating power flow controller access line to obtain the direct-axis voltage at the G end, the direct-axis voltage at the R end and the quadrature-axis voltage at the R end of the rotating power flow controller;

[0031] A voltage calculation unit, used for calculating the d-axis voltage and q-axis voltage of the rotating power flow controller according to the actual active power value and reactive power value of the rotating power flow controller, the direct-axis voltage at the G end, the direct-axis voltage at the R end, the quadrature-axis voltage at the R end of the rotating power flow controller, and the impedance of the rotating power flow controller connected in series with the line;

[0032] A determination unit, used to obtain a voltage amplitude and a voltage angle of a rotating power flow controller connected in series to a line according to a d-axis voltage and a q-axis voltage of the rotating power flow controller;

[0033] The reference value calculation unit is used to obtain a rotation angle reference value of the rotating power flow controller based on the voltage amplitude and voltage angle of the line connected in series with the rotating power flow controller.

[0034] The voltage calculation unit is Calculate the d-axis voltage and q-axis voltage of the rotating power flow controller, where U RPFCd and U RPFCq are the d-axis voltage and q-axis voltage of the rotating power flow controller, U Gd is the direct-axis voltage at the G end of the rotary power flow controller, U Rd is the direct-axis voltage at the R terminal of the rotary power flow controller, U Rq is the quadrature-axis voltage at the R end of the rotating power flow controller, P and Q are the actual active power value and reactive power value of the rotating power flow controller, R and L are the resistance and inductance of the rotating power flow controller, and ω is the angular frequency.

[0035] The technical solution adopted by the present invention to solve its technical problem is: to provide an electronic device, including a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned rotating power flow controller power control method when executing the computer program.

[0036] The technical solution adopted by the present invention to solve its technical problem is: providing a computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, the steps of the power control method of the rotating power flow controller are implemented.

[0037] Beneficial Effects

[0038] Due to the adoption of the above-mentioned technical scheme, the present invention has the following advantages and positive effects compared with the prior art: the present invention aims at the power control problem of the rotating power flow controller, takes the carrying capacity index of the active distribution network as the first control target, and solves the optimal power value of the rotating power flow controller under the conditions of satisfying various constraints; takes the rotation angle of the rotating power flow controller as the second control target, and utilizes double closed-loop PI control to obtain the rotation angle reference value of the rotating power flow controller, so as to realize the power control of the rotating power flow controller considering the improvement of the carrying capacity of the active distribution network. The present invention can improve the carrying capacity of the distribution network and the accuracy of power control, realize the technical goal of quickly and accurately controlling the power flow of the power flow controller, and achieve the technical effect of improving the carrying capacity of the distribution network. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a flow chart of a power control method of a rotating power flow controller according to a first embodiment of the present invention;

[0040] Figure 2 is a block diagram of rotation angle control in a first embodiment of the present invention;

[0041] Figure 3 is a schematic diagram of a topological structure of a distribution network according to an embodiment of the present invention;

[0042] Figure 4 4 is a simplified circuit diagram of a distribution network according to an embodiment of the present invention. DETAILED DESCRIPTION

[0043] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0044] The first embodiment of the present invention relates to a power control method for a rotating power flow controller. The method uses the distribution network carrying capacity index as the first control target, and solves the optimal power value of the rotating power flow controller under various constraints; uses the rotation angle of the rotating power flow controller as the second control target, and uses double closed-loop PI control to obtain the rotation angle reference value of the rotating power flow controller, thereby realizing the power control of the rotating power flow controller considering the improvement of the carrying capacity of the active distribution network. Figure 1 As shown, the following steps are included:

[0045] Step 1: Taking the distribution network carrying capacity index as the target, and taking the power flow constraint, node voltage constraint, and line current carrying capacity constraint as the constraint conditions, a power optimization model of the rotating power flow controller is constructed.

[0046] In this step, the objective function of the power optimization model of the rotating power flow controller is expressed as:

[0047] F1=αF M +βF L

[0048] Among them, F1 is the carrying capacity of the distribution network, F M is the power flow balance, F L is the line capacity margin, α and β are weight coefficients, and α+β=1, 0≤α≤1, 0≤β≤1.

[0049] Flow balance F M It can be expressed as:

[0050]

[0051] Among them, S M,1,t and S M,2,t are the apparent powers flowing through the main transformers of the two flexible interconnected lines at time t; S max,1 and S max,2 are the rated apparent powers of the main transformers of the two flexible interconnected lines respectively; T is the number of time periods.

[0052] Line capacity margin F L It can be expressed as:

[0053]

[0054] Where N is the total number of branches of the two flexible interconnection lines; I ij,n,t is the branch current flowing through the nth line at time t; I max,n is the rated current of the nth line.

[0055] In this step, the constraints of the power optimization model of the rotating power flow controller are expressed as:

[0056]

[0057] Among them, V i and V j are the voltages at nodes i and j, respectively, and r ij is the resistance of branch ij, x ij is the reactance of branch ij, P ij is the active power flowing through branch ij, Q ij is the reactive power flowing through branch ij, k is the end node of the branch with node j as the first node, P L,j represents the active power of the load at node j, P DG,j represents the active power of the distributed generation at node j, P RPFC.j is the active power flowing through the rotating power flow controller at node j; Q L,j is the reactive power of the load at node j; Q RPFC.j is the reactive power flowing through the rotating power flow controller at node j, S ij,max is the maximum apparent power allowed to pass through line ij.

[0058] Step 2, solving the power optimization model of the rotating power flow controller to obtain the optimal power value of the rotating power flow controller. In this step, the power optimization model of the rotating power flow controller is solved using a Cplex solver to obtain the optimal power value of the rotating power flow controller.

[0059] Step 3: obtaining a rotation angle reference value of the rotating power flow controller based on the optimal power value of the rotating power flow controller.

[0060] like Figure 2 As shown, this step specifically includes:

[0061] The optimal power value of the rotating power flow controller (including the optimal active power value and the optimal reactive power value) is used as the set value P ref and Q ref Input the inner loop controller in the double closed-loop PI controller to obtain the actual active power value P and reactive power value Q of the rotating power flow controller;

[0062] The three-phase voltage U at the R end of the rotating power flow controller connected to the line Rabc and the three-phase voltage U at the G end Gabc Perform dq decomposition to obtain the direct axis voltage U at the G end of the rotating power flow controller Gd , R terminal direct axis voltage U Rd and R-terminal quadrature axis voltage U Rq ;

[0063] According to the actual active power value P, reactive power value Q, and G-terminal direct axis voltage U of the rotating power flow controller, Gd , R terminal direct axis voltage URd , R-end quadrature axis voltage U Rq , and the impedance Z of the rotating power flow controller connected in series to the line RPFC Calculate the d-axis voltage U of the rotating power flow controller RPFCd and q-axis voltage U RPFCq , where the calculation method is:

[0064]

[0065] According to the d-axis voltage U of the rotating power flow controller RPFCd and q-axis voltage U RPFCq Get the voltage amplitude of the rotating power flow controller connected in series to the line and voltage angle ∠RPFC;

[0066] Based on the voltage amplitude of the line connected in series with the rotating power flow controller The rotation angle reference value of the rotating power flow controller is obtained by adding the voltage angle ∠RPFC, that is, the first rotation angle reference value α inside the rotating power flow controller. 1ref and the second rotation angle reference value α 2ref Specifically, according to Figure 4 The voltage-current relationship combined with Ohm's law gives in, is the current at terminal G, T RPFC is the coefficient obtained according to the rotation angle of the rotating power flow controller, and its expression is: k is the voltage transformation ratio of RPFC.

[0067] Step 4: Using the rotation angles θ1 and θ2 of the rotating power flow controller as the control targets of the outer loop controller in the double closed-loop PI controller, the rotation angle reference value (i.e., the first rotation angle reference value α 1ref and the second rotation angle reference value α 2ref ) is used as the outer loop controller input in the double closed-loop PI controller to obtain a power control instruction (i.e., the first actual value of the rotation angle α1 and the second actual value of the rotation angle α2 inside the rotating power flow controller), and the power control of the rotating power flow controller is completed using the power control instruction.

[0068] Below Figure 3 The distribution network shown is an embodiment to further illustrate the present invention. The distribution network in this embodiment includes 10kV bus 1 and 10kV bus 2, 10kV bus 1 contains nodes 1-5, 10kV bus 2 contains nodes 6-10, and RPFC is configured between nodes 5 and 10 to realize the interconnection of two lines. Figure 4 for Figure 3 The simplified circuit diagram of the distribution network shown in the figure is obtained by simplifying the two lines according to the topological structure diagram. Figure 4The meanings of various parameters of RPFC power control in the second control target can be clearly understood.

[0069] Through example simulation analysis Figure 2 The distribution network topology in the example has three schemes:

[0070] Solution 1: The distribution network operates in open loop and RPFC is not configured.

[0071] Solution 2: Configure RPFC, but the optimal power flow value of RPFC is set based on experience.

[0072] Solution 3: configure RPFC and use the method of the first embodiment to set the optimal power value of RPFC.

[0073] Table 1 Comparison of simulation results under different schemes

[0074] Solution No. Network loss / MW Trend Balance Line capacity margin Bearing capacity index Solution 1 2.37 0.879 0.853 0.866 Solution 2 2.15 0.892 0.869 0.881 Solution 3 2.09 0.916 0.877 0.897

[0075] From the perspective of network loss: Scheme 1 has the highest network loss, which indicates that without RPFC, the distribution network operation will generate large network losses. After RPFC is configured, the network losses of Schemes 2 and 3 are lower than those of Scheme 1, indicating that flexible interconnection through RPFC can effectively reduce network losses.

[0076] From the analysis of power flow balance: In the case of scheme 1 without configuring RPFC, the power flow distribution is relatively dispersed. By configuring RPFC, scheme 2 builds a power flow transfer channel, and the power flow balance is improved to 0.892, which improves the power flow distribution. The power flow balance of scheme 3 is the highest, reaching 0.916, showing that the method of the first implementation method has significantly improved the power flow balance.

[0077] From the perspective of line capacity margin analysis: the line capacity margin of solution 1 is 0.853, indicating that some lines are overloaded. Solution 2 increases the line capacity margin to 0.869 by configuring RPFC, improving the line load situation. The line capacity margin of solution 3 is 0.877, further optimizing the power flow distribution of the line and reducing the risk of overload.

[0078] Comprehensive analysis from the carrying capacity index: The carrying capacity index of Scheme 1 is 0.866, which is the lowest among the three schemes, indicating that the overall carrying capacity of the distribution network is insufficient when RPFC is not configured. Scheme 2 sets the power value of RPFC by experience, and increases the carrying capacity index to 0.881, indicating that RPFC has a certain effect in improving the carrying capacity of the distribution network. The carrying capacity index of Scheme 3 is the highest, which is 0.897, indicating that the optimal power value of RPFC set by the method of the first implementation method can maximize the carrying capacity of the distribution network.

[0079] In summary, configuring RPFC can play a good role in optimizing the operation of the distribution network, and setting the optimal power value of RPFC using the method of the first implementation (Scheme 3) performs best in all indicators, while reducing network losses and improving power flow balance and line capacity margin, thereby improving the carrying capacity of the distribution network.

[0080] A second embodiment of the present invention relates to a rotating power flow controller power control device, comprising:

[0081] A construction module is used to construct a power optimization model of a rotating power flow controller with the distribution network carrying capacity index as the target and the power flow constraint, node voltage constraint, and line current carrying capacity constraint as the constraint conditions;

[0082] A solution module, used for solving the power optimization model of the rotating power flow controller to obtain the optimal power value of the rotating power flow controller;

[0083] A calculation module, used for obtaining a rotation angle reference value of the rotating power flow controller based on the optimal power value of the rotating power flow controller;

[0084] The control module is used to use the rotation angle of the rotating power flow controller as the control target of the controller, use the rotation angle reference value as the controller input, obtain the power control instruction, and use the power control instruction to complete the power control of the rotating power flow controller.

[0085] The objective function of the power optimization model of the rotating power flow controller constructed by the building module is expressed as: F1 = αF M +βF L , where F1 is the carrying capacity of the distribution network, F M is the power flow balance, expressed as: F L is the line capacity margin, expressed as: α and β are weight coefficients, and α+β=1,0≤α≤1,0≤β≤1, S M,1,t and S M,2,t are the apparent powers flowing through the main transformers of the two flexible interconnected lines at time t; S max,1 and S max,2 are the rated apparent powers of the main transformers of the two flexible interconnected lines respectively; T is the number of time periods; N is the total number of branches of the two flexible interconnected lines; I ij,n,t is the branch current flowing through the nth line at time t; I max,n is the rated current of the nth line.

[0086] The constraints of the power optimization model of the rotating power flow controller constructed by the building module are expressed as follows: Among them, V i and V jare the voltages at nodes i and j, respectively, and r ij is the resistance of branch ij, x ij is the reactance of branch ij, P ij is the active power flowing through branch ij, Q ij is the reactive power flowing through branch ij, k is the end node of the branch with node j as the first node, P L,j represents the active power of the load at node j, P DG,j represents the active power of the distributed generation at node j, P RPFC.j is the active power flowing through the rotating power flow controller at node j; Q L,j is the reactive power of the load at node j; Q RPFC.j is the reactive power flowing through the rotating power flow controller at node j, S ij,max is the maximum apparent power allowed to pass through line ij.

[0087] The calculation module comprises:

[0088] A power value calculation unit, used to input the optimal power value of the rotating power flow controller as a set value into the controller to obtain the actual active power value and reactive power value of the rotating power flow controller;

[0089] A decomposition unit is used to perform dq decomposition on the three-phase voltage at the R end and the three-phase voltage at the G end of the rotating power flow controller access line to obtain the direct-axis voltage at the G end, the direct-axis voltage at the R end and the quadrature-axis voltage at the R end of the rotating power flow controller;

[0090] A voltage calculation unit, used for calculating the d-axis voltage and q-axis voltage of the rotating power flow controller according to the actual active power value and reactive power value of the rotating power flow controller, the direct-axis voltage at the G end, the direct-axis voltage at the R end, the quadrature-axis voltage at the R end of the rotating power flow controller, and the impedance of the rotating power flow controller connected in series with the line;

[0091] A determination unit, used to obtain a voltage amplitude and a voltage angle of a rotating power flow controller connected in series to a line according to a d-axis voltage and a q-axis voltage of the rotating power flow controller;

[0092] The reference value calculation unit is used to obtain a rotation angle reference value of the rotating power flow controller based on the voltage amplitude and voltage angle of the line connected in series with the rotating power flow controller.

[0093] The voltage calculation unit is Calculate the d-axis voltage and q-axis voltage of the rotating power flow controller, where U RPFCd and U RPFCq are the d-axis voltage and q-axis voltage of the rotating power flow controller, U Gd is the direct-axis voltage at the G end of the rotary power flow controller, U Rdis the direct-axis voltage at the R terminal of the rotary power flow controller, U Rq is the quadrature-axis voltage at the R end of the rotating power flow controller, P and Q are the actual active power value and reactive power value of the rotating power flow controller, R and L are the resistance and inductance of the rotating power flow controller, and ω is the angular frequency.

[0094] The third embodiment of the present invention relates to an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the power control method of the rotating power flow controller of the first embodiment when executing the computer program.

[0095] A fourth embodiment of the present invention relates to a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the power control method of the rotating power flow controller of the first embodiment.

[0096] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) that contain computer-usable program code.

[0097] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0098] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction method, which is implemented in the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0099] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0100] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A power control method for a rotating power flow controller, characterized in that: The following steps are involved: Taking the distribution network carrying capacity index as the target, and taking the power flow constraint, node voltage constraint, and line current carrying capacity constraint as the constraint conditions, a power optimization model of the rotating power flow controller is constructed. Solving the power optimization model of the rotating power flow controller to obtain the optimal power value of the rotating power flow controller; Obtaining a rotation angle reference value of the rotating power flow controller based on the optimal power value of the rotating power flow controller; The rotation angle of the rotating power flow controller is used as the control target of the controller, the rotation angle reference value is used as the controller input, a power control instruction is obtained, and the power control of the rotating power flow controller is completed by using the power control instruction.

2. The power control method of the rotating power flow controller according to claim 1, characterized in that: The objective function of the power optimization model of the rotating power flow controller is expressed as: F1 = αF M +βF L , where F1 is the carrying capacity of the distribution network, F M is the power flow balance, expressed as: F L is the line capacity margin, expressed as: α and β are weight coefficients, and α+β=1,0≤α≤1,0≤β≤1, S M,1,t and S M,2,t are the apparent powers flowing through the main transformers of the two flexible interconnected lines at time t; S max,1 and S max,2 are the rated apparent powers of the main transformers of the two flexible interconnected lines respectively; T is the number of time periods; N is the total number of branches of the two flexible interconnected lines; I ij,n,t is the branch current flowing through the nth line at time t; I max,n is the rated current of the nth line.

3. The power control method of the rotating power flow controller according to claim 1, characterized in that: The constraints of the power optimization model of the rotating power flow controller are expressed as: Among them, V i and V j are the voltages at nodes i and j, respectively, and r ij is the resistance of branch ij, x ij is the reactance of branch ij, P ij is the active power flowing through branch ij, Q ij is the reactive power flowing through branch ij, k is the end node of the branch with node j as the first node, P L,j represents the active power of the load at node j, P DG,j represents the active power of the distributed generation at node j, P RPFC.j is the active power flowing through the rotating power flow controller at node j; Q L,j is the reactive power of the load at node j; Q RPFC.j is the reactive power flowing through the rotating power flow controller at node j, S ij,max is the maximum apparent power allowed to pass through line ij.

4. The power control method of the rotating power flow controller according to claim 1, characterized in that: The step of obtaining a rotation angle reference value of the rotating power flow controller based on the optimal power value of the rotating power flow controller specifically includes: Inputting the optimal power value of the rotating power flow controller into the controller as a set value to obtain the actual active power value and reactive power value of the rotating power flow controller; Perform dq decomposition on the three-phase voltage at the R end and the three-phase voltage at the G end of the line to which the rotating power flow controller is connected, and obtain the direct-axis voltage at the G end, the direct-axis voltage at the R end, and the quadrature-axis voltage at the R end of the rotating power flow controller; Calculate the d-axis voltage and q-axis voltage of the rotating power flow controller according to the actual active power value, reactive power value, the direct-axis voltage at the G end, the direct-axis voltage at the R end, the quadrature-axis voltage at the R end of the rotating power flow controller, and the impedance of the rotating power flow controller connected in series with the line; According to the d-axis voltage and q-axis voltage of the rotating power flow controller, the voltage amplitude and voltage angle of the line connected in series with the rotating power flow controller are obtained; A rotation angle reference value of the rotating power flow controller is obtained based on the voltage amplitude and voltage angle of the line connected in series with the rotating power flow controller.

5. The power control method of the rotating power flow controller according to claim 4, characterized in that: The d-axis voltage and q-axis voltage of the rotating power flow controller are Calculated, where U RPFCd and U RPFCq are the d-axis voltage and q-axis voltage of the rotating power flow controller, U Gd is the direct-axis voltage at the G end of the rotary power flow controller, U Rd is the direct-axis voltage at the R terminal of the rotary power flow controller, U Rq is the quadrature-axis voltage at the R end of the rotating power flow controller, P and Q are the actual active power value and reactive power value of the rotating power flow controller, R and L are the resistance and inductance of the rotating power flow controller, and ω is the angular frequency.

6. A power control device for a rotating power flow controller, characterized in that: include: A construction module is used to construct a power optimization model of a rotating power flow controller with the distribution network carrying capacity index as the target and the power flow constraint, node voltage constraint, and line current carrying capacity constraint as the constraint conditions; A solution module, used for solving the power optimization model of the rotating power flow controller to obtain the optimal power value of the rotating power flow controller; A calculation module, used for obtaining a rotation angle reference value of the rotating power flow controller based on the optimal power value of the rotating power flow controller; The control module is used to use the rotation angle of the rotating power flow controller as the control target of the controller, use the rotation angle reference value as the controller input, obtain the power control instruction, and use the power control instruction to complete the power control of the rotating power flow controller.

7. The power control device of the rotating power flow controller according to claim 6, characterized in that: The objective function of the power optimization model of the rotating power flow controller constructed by the building module is expressed as: F1 = αF M +βF L , where F1 is the carrying capacity of the distribution network, F M is the power flow balance, expressed as: F L is the line capacity margin, expressed as: α and β are weight coefficients, and α+β=1,0≤α≤1,0≤β≤1, S M,1,t and S M,2,t are the apparent powers flowing through the main transformers of the two flexible interconnected lines at time t; S max,1 and S max,2 are the rated apparent powers of the main transformers of the two flexible interconnected lines respectively; T is the number of time periods; N is the total number of branches of the two flexible interconnected lines; I ij,n,t is the branch current flowing through the nth line at time t; I max,n is the rated current of the nth line.

8. The power control device of the rotating power flow controller according to claim 6, characterized in that: The constraints of the power optimization model of the rotating power flow controller constructed by the building module are expressed as follows: Among them, V i and V j are the voltages at nodes i and j, respectively, and r ij is the resistance of branch ij, x ij is the reactance of branch ij, P ij is the active power flowing through branch ij, Q ij is the reactive power flowing through branch ij, k is the end node of the branch with node j as the first node, P L,j represents the active power of the load at node j, P DG,j represents the active power of the distributed generation at node j, P RPFC.j is the active power flowing through the rotating power flow controller at node j; Q L,j is the reactive power of the load at node j; Q RPFC.j is the reactive power flowing through the rotating power flow controller at node j, S ij,max is the maximum apparent power allowed to pass through line ij.

9. The power control device of the rotating power flow controller according to claim 6, characterized in that: The calculation module comprises: A power value calculation unit, used to input the optimal power value of the rotating power flow controller as a set value into the controller to obtain the actual active power value and reactive power value of the rotating power flow controller; A decomposition unit is used to perform dq decomposition on the three-phase voltage at the R end and the three-phase voltage at the G end of the rotating power flow controller access line to obtain the direct-axis voltage at the G end, the direct-axis voltage at the R end and the quadrature-axis voltage at the R end of the rotating power flow controller; A voltage calculation unit, used for calculating the d-axis voltage and q-axis voltage of the rotating power flow controller according to the actual active power value and reactive power value of the rotating power flow controller, the direct-axis voltage at the G end, the direct-axis voltage at the R end, the quadrature-axis voltage at the R end of the rotating power flow controller, and the impedance of the rotating power flow controller connected in series with the line; A determination unit, used to obtain a voltage amplitude and a voltage angle of a rotating power flow controller connected in series to a line according to a d-axis voltage and a q-axis voltage of the rotating power flow controller; The reference value calculation unit is used to obtain a rotation angle reference value of the rotating power flow controller based on the voltage amplitude and voltage angle of the line connected in series with the rotating power flow controller.

10. The power control device of the rotating power flow controller according to claim 9, characterized in that: The voltage calculation unit is Calculate the d-axis voltage and q-axis voltage of the rotating power flow controller, where U RPFCd and U RPFCq are the d-axis voltage and q-axis voltage of the rotating power flow controller, U Gd is the direct-axis voltage at the G end of the rotary power flow controller, U Rd is the direct-axis voltage at the R terminal of the rotary power flow controller, U Rq is the quadrature-axis voltage at the R end of the rotating power flow controller, P and Q are the actual active power value and reactive power value of the rotating power flow controller, R and L are the resistance and inductance of the rotating power flow controller, and ω is the angular frequency.

11. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the rotating power flow controller power control method as described in any one of claims 1-5 are implemented.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the power control method of the rotating power flow controller as described in any one of claims 1-5 are implemented.

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