Power flow optimization calculation method and device of power distribution network, electronic equipment and storage medium
By constructing a total power loss model and branch flow model, considering the reactive power of the electrical energy router port, the problem of insufficient calculation accuracy in the existing technology is solved, and the accuracy of trend optimization calculation is improved.
Patent Information
- Application Number
- CN202310679055.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-08
- Publication Date
- 2024-12-10
AI Technical Summary
The existing current optimization calculation method fails to fully consider the reactive power when considering the port loss of the electric energy router, resulting in insufficient calculation accuracy, especially when the port reactive power changes, the impact of equipment loss cannot be accurately described.
The total power loss model of multi-port power router is constructed, and the branch current model of the entire distribution network topology is determined by the branch current method, and the power constraint relationship of the multi-port power router is determined based on the total power loss model and the branch current model is considered. Reactive power of the port to create a more accurate loss model.
The current optimization calculation accuracy of multi-port power routers in the distribution network is improved, the error of the original loss model is reduced, and the accuracy of the calculation results is enhanced.
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Figure CN119109002A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the technical field of power system analysis, and in particular to a method, device, electronic device and computer storage medium for power flow optimization calculation of a distribution network. Background Art
[0002] With the rapid development of power electronics technology and the widespread access to large-scale distributed renewable energy, the power system is also developing towards the stage of coordinated and optimized operation of "source, grid, load and storage". Therefore, in recent years, new power electronic devices such as electrical energy routers (EER) have also been gradually applied to power supply and distribution systems. The electrical energy router is a multi-port, multi-flow energy exchange device based on power electronics technology. It has evolved from the early solid-state transformer (SST). The electrical energy router can provide separate interfaces for various devices such as distributed power sources and energy storage in the network to achieve multi-directional flow and flexible control of energy. Therefore, the use of a power supply system based on the networking of electrical energy routers can reduce additional links such as converters and improve the overall energy efficiency of the distribution network.
[0003] Traditional power flow optimization calculations simplify the port loss of the power router to a multiple of the port power; or establish a detailed model based on its internal structure, but the use of a detailed model brings too many supplementary constraints, which reduces the solution speed during large-scale optimization. Currently, there is an EER loss modeling method based on the port loss model, which uses a quadratic function model to describe the relationship between port power and port loss, so as to describe the loss of EER under any operating state, thereby improving the speed of power flow calculation while ensuring accuracy.
[0004] However, the current power system also has certain requirements for the reactive output capacity of the power router. However, the above methods do not consider the influence of the reactive power of the port. When the reactive power of the port changes, only the quadratic function form of active power cannot accurately describe the influence of reactive fluctuations on equipment losses. Therefore, it is necessary to take the reactive power of the port into account when establishing the loss model of the power router, so as to model the loss more accurately and improve the calculation accuracy of the power flow optimization. Summary of the invention
[0005] The purpose of the present disclosure is to provide a method, device, electronic device and computer storage medium for power flow optimization calculation of a distribution network, thereby overcoming the problem that the power flow optimization calculation accuracy of a distribution network containing a multi-port power router cannot be improved to a certain extent due to the limitations and defects of related technologies.
[0006] Other features and advantages of the present disclosure will become apparent from the following detailed description, or may be learned in part by the practice of the present disclosure.
[0007] According to one aspect of the present disclosure, a method for optimizing power flow calculation of a distribution network is provided, comprising: constructing a total power loss model of a multi-port power router; using a branch power flow method to determine a branch power flow model of any branch in the entire distribution network topology; and determining a power constraint relationship of the multi-port power router based on the total power loss model and the branch power flow model.
[0008] In one embodiment of the present disclosure, a total power loss model of a multi-port power router is constructed, including: obtaining a power loss expression of any port of the multi-port power router; determining a power loss expression of the multi-port power router expressed in apparent power, where the apparent power includes active power and reactive power; and obtaining a total power loss model of the multi-port power router expressed in apparent power.
[0009] In one embodiment of the present disclosure, obtaining a power loss expression of any port of a multi-port power router includes: Among them, P loss_i is the power loss expression of any port of the multi-port power router, I i is the current flowing through any port, and a, b, and c are constant coefficients.
[0010] In one embodiment of the present disclosure, determining a power loss expression of a multi-port power router expressed in apparent power includes: Among them, P loss_i is the power loss expression of any port, S is the apparent power of the port, i is the serial number of the port, and a, b, and c are constant coefficients.
[0011] In one embodiment of the present disclosure, obtaining a total power loss model of a multi-port power router expressed in apparent power includes: Among them, P loss is the total power loss model of multiple ports of the multi-port power router, S is the apparent power of the port, i is the serial number of the port, n is the number of ports of the multi-port power router, and a, b and c are constant coefficients.
[0012] In one embodiment of the present disclosure, a branch flow method is used to determine a branch flow model of any branch in the entire distribution network topology, including: obtaining a power constraint relationship flowing through the branch; and determining a power constraint relationship of a node injected into the branch.
[0013] In one embodiment of the present disclosure, obtaining a power constraint relationship flowing through a branch includes:
[0014]
[0015]
[0016] Among them, V i 、V j is the node voltage, I ij is the branch current, P ij , Q ij are the active power and reactive power flowing through branch ij, r ij is the resistance of branch ij, x ij is the reactance of branch ij.
[0017] In one embodiment of the present disclosure, determining a power constraint relationship of a node of an injection branch includes:
[0018]
[0019]
[0020] Among them, P j and Q j is the active power and reactive power injected by node j, r ij is the resistance of branch ij, x ij is the reactance of branch ij, P ij , Q ij are the active power and reactive power flowing through branch ij respectively.
[0021] In one embodiment of the present disclosure, obtaining a power constraint relationship flowing through a branch includes: linearizing the power constraint relationship of the branch; obtaining the linearized power constraint relationship of the branch; and performing second-order cone relaxation on the linearized power constraint relationship of the branch.
[0022] In one embodiment of the present disclosure, a linear transformation is performed on the power constraint relationship of the branch, including:
[0023] U i =V i 2
[0024]
[0025] Among them, V i is the node voltage, I ij is the branch current.
[0026] In one embodiment of the present disclosure, obtaining a linearized power constraint relationship of a branch includes:
[0027]
[0028] Among them, P ij , Qij are the active power and reactive power flowing through branch ij respectively.
[0029] In one embodiment of the present disclosure, a second-order cone relaxation is performed on the power constraint relationship of the linearized branch, including:
[0030]
[0031] Among them, V i is the node voltage, I ij is the branch current, P ij , Q ij are the active power and reactive power flowing through branch ij respectively.
[0032] In one embodiment of the present disclosure, determining the power constraint relationship of the node of the injection branch includes: determining the power constraint relationship of the network injection power, load power and port power of the node of the injection branch.
[0033] In one embodiment of the present disclosure, determining the power constraint relationship between the network injection power of the node of the injection branch, the load power, and the port power of the power router includes:
[0034] P j =P s,j +P sst,j -P L,j
[0035] Q j =Q s,j +Q sst,j -Q L,j
[0036] Among them, P s,j , Q s,j The active power and reactive power injected into the network node, P L,j , Q L,j is the load active power and reactive power, P sst,j , Q sst,j It is the active power and reactive power of the power router port.
[0037] In one embodiment of the present disclosure, a power constraint relationship of a multi-port power router is determined based on a total power loss model and a branch power flow model, including: linearizing the total power loss model of the multi-port power router; obtaining a linearized total power loss model of the multi-port power router; performing a second-order cone relaxation on the linearized total power loss model; and establishing a power constraint relationship between the total power loss model of the multi-port power router and the power of multiple ports.
[0038] In one embodiment of the present disclosure, a linear transformation is performed on the total power loss model of the multi-port power router, including:
[0039]
[0040] Where Si is the apparent power of the multi-port power router port, U 0i is the node voltage, I ij is the branch current.
[0041] In one embodiment of the present disclosure, obtaining a linearized total power loss model of a multi-port power router includes:
[0042]
[0043] Where Si is the apparent power of the multi-port power router port, U 0i is the node voltage, I ij is the branch current, P loss The total power loss model of the linearized multi-port power router.
[0044] In one embodiment of the present disclosure, a second-order cone relaxation is performed on the linearized total power loss model, including:
[0045]
[0046] Wherein, Si is the apparent power of the multi-port power router port, Pi is the active power of the multi-port power router port, and Qi is the reactive power of the multi-port power router port.
[0047] In one embodiment of the present disclosure, a power constraint relationship between a total power loss model of a multi-port power router and the power of multiple ports is established, including:
[0048]
[0049] Among them, P loss is the total power loss model of the linearized multi-port power router, P sst,j , Q sst,j It is the active power and reactive power of the power router port.
[0050] The embodiment of the present disclosure provides a power flow optimization calculation method for a distribution network, wherein the distribution network includes a multi-port power router, and the power flow optimization calculation method includes: constructing a total power loss model of the multi-port power router; using the branch power flow method to determine the branch power flow model of any branch in the entire distribution network topology; and determining the power constraint relationship of the multi-port power router according to the total power loss model and the branch power flow model. Considering the reactive power of the port, a loss model of the multi-port power router is established, which reduces the error of the original loss model and improves the power flow optimization calculation accuracy of the distribution network containing the multi-port power router.
[0051] According to another aspect of the present disclosure, a power flow optimization calculation device for a distribution network is provided. The distribution network includes a multi-port power router. The power flow optimization calculation device includes: a total power loss construction module, which is used to construct a total power loss model of the multi-port power router; a branch power flow model determination module, which is used to determine the branch power flow model of any branch in the entire distribution network topology by using a branch power flow method; a power constraint determination module, which is used to determine the power constraint relationship of the multi-port power router according to the total power loss model and the branch power flow model.
[0052] According to another aspect of the present disclosure, an electronic device is provided, comprising: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to execute the power flow optimization calculation method for a distribution network in any embodiment by executing the executable instructions.
[0053] According to another aspect of the present disclosure, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the power flow optimization calculation method for a distribution network in any embodiment is implemented.
[0054] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS
[0055] Figure 1 FIG. 4 is an internal circuit diagram of a multi-port power router according to an exemplary embodiment of the present disclosure.
[0056] Figure 2 It is a flow chart of a power flow optimization calculation method for a distribution network according to an exemplary embodiment of the present disclosure.
[0057] Figure 3 It is a schematic diagram of loss modeling of an exemplary embodiment of the present disclosure.
[0058] Figure 4 It is a flow chart of a method for establishing a loss model based on a simulation platform according to an exemplary embodiment of the present disclosure.
[0059] Figure 51 is a loss model error verification waveform considering reactive power and not considering reactive power according to an exemplary embodiment of the present disclosure.
[0060] Figure 6 1 is a loss model error verification waveform considering reactive power and not considering reactive power according to an exemplary embodiment of the present disclosure.
[0061] Figure 7 1 is a loss model error verification waveform considering reactive power and not considering reactive power according to an exemplary embodiment of the present disclosure.
[0062] Figure 8 1 is a loss model error verification waveform considering reactive power and not considering reactive power according to an exemplary embodiment of the present disclosure.
[0063] Fig. 9 It is a branch flow model of an exemplary embodiment of the present disclosure.
[0064] Fig.10 It is a schematic diagram of a power flow optimization calculation device for a distribution network according to an exemplary embodiment of the present disclosure.
[0065] Fig.11 is a structural block diagram of an electronic device according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION
[0066] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the disclosure will be more comprehensive and complete and to fully convey the concepts of the example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0067] This patent proposes a multi-port power router loss modeling method that takes into account the reactive power of the port, conducts a theoretical analysis of the various parts of the power router loss, establishes a polynomial loss model based on apparent power, and can be applied to the power flow optimization calculation of the distribution network, effectively improving the accuracy of the power flow optimization calculation.
[0068] The embodiment of the present disclosure provides a power flow optimization calculation method for a distribution network, which considers the reactive power of the port, establishes a loss model of a multi-port power router, reduces the error of the original loss model, and improves the power flow optimization calculation accuracy of the distribution network containing the multi-port power router. The power flow optimization calculation method for the distribution network provided by the embodiment of the present disclosure is described below in conjunction with the accompanying drawings.
[0069] The method includes the following contents: by analyzing the various parts of the loss in the power router, the relationship between the loss of each port of the power router and the port current is obtained, and then the port loss is described in the form of apparent power to obtain the power router port loss model considering reactive power, and the apparent power of each port is fitted with the port loss to calculate the coefficient value in the model. Under certain conditions where the internal structure of the power router cannot be obtained, the loss of each port cannot be obtained, and the total loss of the power router can only be measured through experiments. At this time, the total loss model of the power router can be established, and this model can be applied to the optimization of the power flow. When optimizing the power flow calculation, the influence of reactive power is considered to improve the accuracy of the power flow calculation results.
[0070] Figure 1 The internal circuit diagram of a multi-port power router included in the power distribution network provided by the embodiment of the present disclosure is shown. For example, the multi-port power router may be a 50kVA four-port power router 100. The power router 100 mainly includes a transformer and an A / D conversion circuit, specifically, a 350V DC connector 101. In addition, a DC load 102, a first AC load 103, and a second AC load 103 are connected to the power router 100, respectively.
[0071] Figure 2 The power flow optimization calculation method of the distribution network shown includes steps S201-S203, wherein the distribution network includes a multi-port power router. It is understandable that the method provided by the embodiment of the present disclosure can be executed by any electronic device. Steps S201-S203 include:
[0072] S201: Constructing a total power loss model of the multi-port power router;
[0073] S202: Determine a branch power flow model of any branch in the entire distribution network topology using a branch power flow method;
[0074] S203: Determine the power constraint relationship of the multi-port power router according to the total power loss model and the branch power flow model.
[0075] The above-mentioned power flow optimization calculation method of the distribution network takes into account the reactive power of the port, establishes a loss model of the multi-port power router, reduces the error of the original loss model, and improves the power flow optimization calculation accuracy of the distribution network containing the multi-port power router.
[0076] Power loss is an important indicator of power routers. The loss of power routers mainly includes the loss of power electronic devices and the loss of high-frequency transformers. The loss of power electronic devices is mainly conduction loss and switching loss. The loss of high-frequency transformers includes copper loss, iron loss and other additional losses, as shown in formula (1):
[0077] P loss =P on +P sw +P Cu +P Fe (1)
[0078] Where P loss is the power loss of the energy router, P on is the switch conduction loss, P sw is the switching loss, P Cu is the transformer copper loss, P Fe is the transformer iron loss.
[0079] Among them, the conduction loss is obtained by the following process. Due to the influence of the on-resistance, the voltage drop of the switch device when it is turned on changes with the on-current. The expression of the on-voltage drop is formula (2):
[0080] u on =U on0 +R th i on (2)
[0081] Among them, u on The current is i on The conduction voltage drop, R th is the on-resistance, U on0 is the pressure drop when no load.
[0082] Therefore, in the steady state, the expression of conduction loss in one switching cycle T is:
[0083]
[0084] Among them I on_rms is the effective value of the switching current.
[0085] In formula (3), U on0 and R th are all constants, so the conduction loss can be described as:
[0086]
[0087] In addition, the switch conduction loss is derived from the following process. The switching loss of the device is related to the device itself, the switching frequency, and the operating conditions during switching. The switching loss is further divided into the turn-on loss E on and turn-off loss E off The switching loss curve of each device can be found in the device parameter table on the official website of the relevant commercial company. Both can be approximately regarded as a primary curve related to current. Therefore, the switching loss is:
[0088]
[0089] where f sw is the switching frequency, E on_i and E off_i is the turn-on loss and turn-off loss of the i-th switch device, the number of switch devices is N, I sw is the switch on and off current, U sw K is the withstand voltage when the switch device is turned off. U It is the voltage correction coefficient introduced when the actual withstand voltage of the switching device is different from the device parameter table given in the official website of the relevant commercial company. k1, b1, k2 and b2 are the coefficients when the turn-on loss and turn-off loss are approximated to a linear curve.
[0090] When the power router is in a stable working state, all parameters in formula (5) can be regarded as constants. Therefore, it can be written as follows:
[0091] P sw =b3I sw +c2(6)
[0092] In addition, the transformer copper loss is obtained by the following process. Transformer copper loss is also called variable loss. If the skin effect and proximity effect are ignored, the copper loss mainly comes from the thermal effect in the coil, that is, it is only related to the resistance of the coil, so the copper loss expression is:
[0093]
[0094] Among them I L is the current flowing through the transformer coil, R L and R TR is the equivalent resistance of the transformer equivalent circuit. So the copper loss can be described as:
[0095]
[0096] In addition, the transformer iron loss is obtained by the following process. Transformer iron loss is also called constant loss. According to a classic empirical formula Steinmetz Equation proposed by Steinmetz, iron loss is mainly related to magnetic flux density, voltage frequency, core volume and core material. The iron loss expression is:
[0097]
[0098] Among them C Fe is the loss coefficient of the core, f is the voltage frequency, B m is the maximum magnetic flux density, V c is the core volume, α and β are constant coefficients.
[0099] When the power router works in a stable condition, for a certain transformer, all parameters do not change, so P Fe is also a constant. It can be written as:
[0100] P F e =c4(10)
[0101] From formulas (2)-(11), the losses of each part of the power router can be unified as:
[0102]
[0103] Where a5, b5 and c5 are constant coefficients related only to the power router hardware.
[0104] When the working condition of the power router does not change, the current of the internal converter does not change either. Therefore, the current of each device in the converter has a certain proportional relationship with the input or output current, namely:
[0105] I i =k i I cvt (12)
[0106] Among them I cvt is the current flowing through the converter, k i is a constant.
[0107] Combining (11) and (12), we can get the converter loss as:
[0108]
[0109] Constructing a total power loss model of the multi-port power router, including:
[0110] Obtaining a power loss expression of any port of the multi-port power router;
[0111] Determine the power loss expression of the multi-port power router in terms of apparent power, wherein the apparent power includes active power and reactive power;
[0112] The total power loss model of the multi-port power router expressed by the apparent power is obtained.
[0113] Specifically, it is obvious that the converter also satisfies the unified form of formula (11). Similarly, when the power router works in a stable state, for each converter:
[0114]
[0115] Where P i and Q iis the active and reactive power flowing through the converter port. For a normally functioning power router, at least one voltage on either side of any converter is controlled and stable, so U i Assuming it to be a constant, the loss model of the power router port can be characterized in the form of apparent power:
[0116]
[0117] Where a, b, c are all constants, S i is the apparent power of the power router port.
[0118] After determining the power router port loss model in the form of formula (15), the loss model establishment method based on the simulation platform can be applied to identify the coefficient parameters of each port. Since the power loss formula of formula (15) is a linear form for parameters a, b, and c, multiple groups of working conditions can be selected and different working conditions can be simulated using simulation software, such as applying an apparent power of a fixed multiple of the capacity to the port, from 0 to 100% of the port capacity, increasing by 10% each time, to obtain a set of port power and corresponding port loss data. The coefficients a, b, and c are identified using the system parameter identification method to obtain a quadratic curve model of the port loss. The power loss under any working condition can be calculated by the apparent power of the port. Therefore, in any application scenario, the total loss formula of the power router can be obtained by combining the apparent power of the multi-port power router ports.
[0119] Figure 3 Shown according to Figure 1 The loss modeling diagram of the four-port power router shown in the figure, where the loss formula of each port is as follows:
[0120]
[0121] Figure 4 The method for establishing a loss model based on a simulation platform is shown, including:
[0122] S401: Establishing a polynomial loss model form for a power router port;
[0123] S402: Building a power router simulation model in the simulation software;
[0124] S403: Select multiple groups of working conditions with different port powers for simulation;
[0125] S404: extracting port apparent power and port loss data under various working conditions;
[0126] S405: performing curve fitting on the parameters by using the least square method to fit the three coefficients a, b, and c of the output port to obtain a quadratic curve model of the port loss;
[0127] S406: Obtain a total loss model of the multi-port power router by combining the port loss models.
[0128] Figures 5 to 8 The error verification waveforms of the loss model with and without reactive power are shown. It can be seen from the figure that when reactive power is considered, the error of the loss model is significantly smaller than that when reactive power is not considered.
[0129] The loss of each port of the power router is established as a loss model in the form of formula (15). By measuring the loss of the power router port under different working conditions for many times, three coefficients can be fitted to give the total loss formula of the multi-port power router.
[0130] However, in many practical situations, it is not possible to accurately obtain the loss value from a single port to the busbar inside the power router, and the total loss of all ports can only be obtained through experimental measurement. Therefore, for a power router with multiple ports, its loss model can be described as
[0131]
[0132] Where P loss is the total power loss of the power router, and its value is the sum of the quadratic polynomials of the apparent power of each port. Therefore, the loss polynomial can be fitted through simulation, and the polynomial coefficients under each port can be solved using the conventional least squares method.
[0133] Fig. 9 The branch power flow model is shown, and the branch power flow method is used to perform optimized power flow calculations. The constraints are written by the power flowing through the branch and the voltages at both ends of the node.
[0134] exist Fig. 9 For a branch ij at a certain moment in time, the following constraints are satisfied:
[0135]
[0136]
[0137] For node j, the following constraints are satisfied:
[0138]
[0139]
[0140] Where V i 、V j is the node voltage, I ij is the branch current, P ij , Q ijare the power flowing through branch ij, P j and Q j is the power injected by node j, rij is the resistance of branch ij, and xij is the reactance of branch ij. Since the above equations contain square terms of voltage and current, it is necessary to linearize the nonlinear terms in the original equations. Therefore, two new variables are established at this time to eliminate the nonlinear part by variable substitution:
[0141] U i =V i 2 (twenty one)
[0142]
[0143] At this time (18) can be transformed into
[0144]
[0145] Therefore, we can further perform convex relaxation and transform the constraint into the form of a standard second-order cone:
[0146]
[0147] The power P injected into node j j , Q j The power balance constraint must also be met:
[0148] P j =P s,j +P sst,j -P L,j (25)
[0149] Q j =Q s,j +Q sst,j -Q L,j (26)
[0150] Where P s,j , Q s,j The power injected into the network node, such as the power provided by the grid node and the distributed power supply node, when there is no external power injection to the j node, P s,j , Q s,j The value of P is zero. L,j , Q L,j is the active and reactive load value of the load, P sst,j , Q sst,j is the power of the power router port, with the direction from the power router to the distribution network being positive. If the network contains energy storage devices, the power exchange with the energy storage devices also needs to be considered.
[0151] In addition, constraints such as line capacity and power factor limit must be met, and the power flow optimization problem is solved through second-order cone optimization. However, in the second-order cone optimization model, only the voltage and current terms are in quadratic form. Therefore, the quadratic form of the apparent power term of the loss model in formula (16) will bring nonlinear parts to the optimization solution, affecting the speed and accuracy of the optimization. Therefore, this part needs to be transformed.
[0152] The port voltage of the power router is limited to the rated voltage during normal operation and can be approximately regarded as a constant U 0i ,but
[0153]
[0154] Furthermore, the power loss constraint of the energy router is also simplified to a linear constraint:
[0155]
[0156] The relationship between apparent power and active and reactive power needs to be described by a second-order cone relaxation, as shown in formula (29).
[0157]
[0158] The power router loss is then linked to the line power through the power balance constraint of the power router:
[0159]
[0160] Where P loss is the power consumption of the energy router. Assuming that the energy router has n ports, due to P sst,j , Q sst,j The outflow direction from the power router is positive, so the sum of the outflow power of each port and the total power loss of the power router is 0.
[0161] In summary, the power router loss model based on the second-order polynomial form of apparent power can be applied to power flow calculation. This method takes into account the influence of reactive power at the power router port and describes the power router loss more accurately, which can improve the accuracy of power flow calculation to a certain extent.
[0162] Fig.10A power flow optimization calculation device 1000 for a distribution network provided by an embodiment of the present disclosure is shown. The distribution network includes a multi-port power router. The power flow optimization calculation device 1000 includes: a total power loss construction module 1001, which is used to construct a total power loss model of the multi-port power router; a branch power flow model determination module 1002, which is used to determine the branch power flow model of any branch in the entire distribution network topology by using a branch power flow method; a power constraint determination module 1003, which is used to determine the power constraint relationship of the multi-port power router according to the total power loss model and the branch power flow model.
[0163] Fig.11 An electronic device 1100 according to an embodiment of the present disclosure is shown. Fig.11 The electronic device 1100 shown is only an example and should not limit the functions and scope of use of the embodiments of the present invention. The electronic device 1000 includes: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to execute the power flow optimization calculation method of the distribution network in any embodiment by executing the executable instructions.
[0164] like Fig.11 As shown, the electronic device 1100 is in the form of a general computing device. The components of the electronic device 1100 may include but are not limited to: at least one processing unit 1110, at least one storage unit 1120, and a bus 1130 connecting different system components (including the storage unit 1120 and the processing unit 1110).
[0165] The storage unit stores program codes, which can be executed by the processing unit 1110, so that the processing unit 1110 performs the steps of various exemplary embodiments of the present invention described in the detailed implementation section of this specification. For example, the processing unit 1110 can perform the following steps: Figure 2 S201 shown in: constructing a total power loss model of the multi-port power router; S202: using the branch flow method to determine the branch flow model of any branch in the entire distribution network topology; S203: determining the power constraint relationship of the multi-port power router based on the total power loss model and the branch flow model.
[0166] The storage unit 1120 may include a readable medium in the form of a volatile storage unit, such as a random access storage unit (RAM) 11201 and / or a cache storage unit 11202 , and may further include a read-only storage unit (ROM) 11203 .
[0167] The storage unit 1120 may also include a program / utility 11204 having a set (at least one) of program modules 11205, such program modules 11205 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.
[0168] Bus 1130 may represent one or more of several types of bus structures, including a memory unit bus or memory unit controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus architectures.
[0169] The electronic device 1100 may also communicate with one or more external devices 1200 (e.g., keyboards, pointing devices, Bluetooth devices, etc.), may also communicate with one or more devices that enable a user to interact with the electronic device 1100, and / or communicate with any device that enables the electronic device 1100 to communicate with one or more other computing devices (e.g., routers, modems, etc.). Such communication may be performed via an input / output (I / O) interface 1150. Furthermore, the electronic device 1100 may also communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) via a network adapter 1160. As shown, the network adapter 1160 communicates with other modules of the electronic device 1100 via a bus 1130. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 1100, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.
[0170] Through the description of the above implementation, it is easy for those skilled in the art to understand that the example implementation described here can be implemented by software, or by software combined with necessary hardware. Therefore, the technical solution according to the implementation of the present disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which can be a personal computer, a server, a terminal device, or a network device, etc.) to execute the method according to the implementation of the present disclosure.
[0171] In an exemplary embodiment of the present disclosure, a computer-readable storage medium is also provided, on which a computer program is stored, and when the computer program is executed by a processor, the power flow optimization calculation method of the distribution network in any embodiment is implemented. In some possible implementations, various aspects of the present invention can also be implemented in the form of a program product, which includes a program code, and when the program product is run on a terminal device, the program code is used to enable the terminal device to execute the steps according to various exemplary embodiments of the present invention described in the specific embodiment section of this specification.
[0172] A program product for implementing the above method according to an embodiment of the present invention is described, which can adopt a portable compact disk read-only memory (CD-ROM) and include program code, and can be run on a terminal device, such as a personal computer. However, the program product of the present invention is not limited thereto, and in this document, a readable storage medium can be any tangible medium containing or storing a program, which can be used by or in combination with an instruction execution system, an apparatus or a device.
[0173] The program product may use any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.
[0174] Computer readable signal media may include data signals propagated in baseband or as part of a carrier wave, in which readable program code is carried. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Readable signal media may also be any readable medium other than a readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.
[0175] The program code contained on the readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the above media.
[0176] Program code for performing the operations of the present invention may be written in any combination of one or more programming languages, including object-oriented programming languages such as Java, C++, etc., and conventional procedural programming languages such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., through the Internet using an Internet service provider).
[0177] It should be noted that, although several modules or units of the device for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present disclosure, the features and functions of two or more modules or units described above can be embodied in one module or unit. On the contrary, the features and functions of one module or unit described above can be further divided into multiple modules or units to be embodied.
[0178] In addition, although the steps of the method in the present disclosure are described in a specific order in the drawings, this does not require or imply that the steps must be performed in this specific order, or that all the steps shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps, etc.
[0179] Through the description of the above implementation, it is easy for those skilled in the art to understand that the example implementation described here can be implemented by software, or by software combined with necessary hardware. Therefore, the technical solution according to the implementation of the present disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which can be a personal computer, a server, a mobile terminal, or a network device, etc.) to execute the method according to the implementation of the present disclosure.
[0180] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.
Claims
1. A power flow optimization calculation method for a distribution network, characterized in that: The distribution network includes a multi-port power router, and the power flow optimization calculation method includes: Constructing a total power loss model of the multi-port power router; The branch flow method is used to determine the branch flow model of any branch in the entire distribution network topology; The power constraint relationship of the multi-port power router is determined according to the total power loss model and the branch power flow model.
2. The power flow optimization calculation method according to claim 1, characterized in that: Constructing a total power loss model of the multi-port power router, including: Obtaining a power loss expression of any port of the multi-port power router; Determine the power loss expression of the multi-port power router in terms of apparent power, wherein the apparent power includes active power and reactive power; The total power loss model of the multi-port power router expressed by the apparent power is obtained.
3. The power flow optimization calculation method according to claim 2, characterized in that: Obtaining a power loss expression of any port of the multi-port power router, including: Among them, P loss_i is the power loss expression of any port of the multi-port power router, I i is the current flowing through any of the ports, and a, b and c are constant coefficients.
4. The power flow optimization calculation method according to claim 3 is characterized in that: Determining the power loss expression of the multi-port power router expressed in apparent power comprises: Among them, P loss_i is the power loss expression of any of the ports, S i is the apparent power of the port, i is the serial number of the port, and a, b and c are constant coefficients.
5. The power flow optimization calculation method according to claim 4, characterized in that: Obtaining the total power loss model of the multi-port power router expressed by the apparent power, comprising: Among them, P loss is the total power loss model of the multiple ports of the multi-port power router, S i is the apparent power of the port, i is the serial number of the port, n is the number of the ports of the multi-port power router, and a, b and c are constant coefficients.
6. The power flow optimization calculation method according to claim 1, characterized in that: The branch flow method is used to determine the branch flow model of any branch in the entire distribution network topology, including: Obtaining a power constraint relationship flowing through the branch; A power constraint relationship of a node injected into the branch is determined.
7. The power flow optimization calculation method according to claim 6, characterized in that: Obtaining a power constraint relationship flowing through the branch, including: Among them, V i 、V j is the node voltage, I ij is the branch current, P ij , Q ij are the active power and reactive power flowing through branch ij, r ij is the resistance of branch ij, x ij is the reactance of branch ij.
8. The power flow optimization calculation method according to claim 6, characterized in that: Determining a power constraint relationship of a node injected into the branch includes: Among them, P j and Q j is the active power and reactive power injected by node j, r ij is the resistance of branch ij, x ij is the reactance of branch ij, P ij , Q ij are the active power and reactive power flowing through branch ij respectively.
9. The power flow optimization calculation method according to claim 7, characterized in that: Obtaining a power constraint relationship flowing through the branch, including: Performing a linear transformation on the power constraint relationship of the branch; Obtaining a linearized power constraint relationship of the branch; A second-order cone relaxation is performed on the power constraint relationship of the branch in the linearization.
10. The power flow optimization calculation method according to claim 9, characterized in that: The power constraint relationship of the branch is linearly transformed, including: Among them, V i is the node voltage, I ij is the branch current.
11. The power flow optimization calculation method according to claim 10, characterized in that: Obtaining a linearized power constraint relationship of the branch, including: Among them, P ij , Q ij are the active power and reactive power flowing through branch ij respectively.
12. The power flow optimization calculation method according to claim 11, characterized in that: Performing a second-order cone relaxation on the power constraint relationship of the linearized branch includes: Among them, V i is the node voltage, I ij is the branch current, P ij , Q ij are the active power and reactive power flowing through branch ij respectively.
13. The power flow optimization calculation method according to claim 8, characterized in that: Determining a power constraint relationship of a node injected into the branch includes: A power constraint relationship among a network injection power of a node injected into the branch, a load power, and a port power of the power router is determined.
14. The power flow optimization calculation method according to claim 13, characterized in that: Determining a power constraint relationship between a network injection power of a node injected into the branch, a load power, and a port power of the power router includes: P j =P s,j +P sst,j -P L,j Q j =Q s,j +Q sst,j -Q L,j Among them, P s,j , Q s,j The active power and reactive power injected into the network node, P L,j , Q L,j is the load active power and reactive power, P sst,j , Q sst,j is the active power and reactive power of the power router port.
15. The power flow optimization calculation method according to claim 14, characterized in that: Determining the power constraint relationship of the multi-port power router according to the total power loss model and the branch power flow model includes: Performing a linear transformation on the total power loss model of the multi-port power router; Acquire the linearized total power loss model of the multi-port power router; Performing a second-order cone relaxation on the linearized total power loss model; A power constraint relationship between the total power loss model of the multi-port power router and the power of the plurality of ports is established.
16. The power flow optimization calculation method according to claim 15, characterized in that: Performing a linear transformation on the total power loss model of the multi-port power router comprises: Wherein, Si is the apparent power of the multi-port power router port, U 0i is the node voltage, I ij is the branch current.
17. The power flow optimization calculation method according to claim 16, characterized in that: Acquiring the linearized total power loss model of the multi-port power router comprises: Wherein, Si is the apparent power of the multi-port power router port, U 0i is the node voltage, I ij is the branch current, P loss The total power loss model of the multi-port power router is linearized.
18. The power flow optimization calculation method according to claim 17, characterized in that: A second-order cone relaxation is performed on the linearized total power loss model, including: Among them, S i is the apparent power of the multi-port power router port, P i is the active power of the multi-port power router port, and Qi is the reactive power of the multi-port power router port.
19. The power flow optimization calculation method according to claim 18, characterized in that: Establishing a power constraint relationship between the total power loss model of the multi-port power router and the power of the plurality of ports includes: Among them, P loss is the total power loss model of the multi-port power router in linearization, P sst,j , Q sst,j It is the active power and reactive power of the power router port.
20. A power flow optimization calculation device for a distribution network, characterized in that: The power distribution network includes a multi-port power router, and the power flow optimization calculation device includes: A total power loss building module, used to build a total power loss model of the multi-port power router; A branch power flow model determination module, used to determine the branch power flow model of any branch in the entire distribution network topology by using a branch power flow method; The power constraint determination module is used to determine the power constraint relationship of the multi-port power router according to the total power loss model and the branch power flow model.
21. An electronic device, characterized in that: include: processor; as well as A memory, configured to store executable instructions of the processor; Wherein, the processor is configured to execute the power flow optimization calculation method for the distribution network described in any one of claims 1 to 19 by executing the executable instructions.
22. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the power flow optimization calculation method for a distribution network described in any one of claims 1 to 19 is implemented.