Power distribution network reactive power optimization control method and system, terminal and medium

Abstract

The invention discloses a power distribution network reactive power optimization control method, and discloses a system with the power distribution network reactive power optimization control method and a storage medium, and the power distribution network reactive power optimization control method comprises the steps: building a power distribution network voltage supporting capability evaluation index, and quantifying the power grid voltage stability level; and a decision basis is provided for reactive power control. Meanwhile, the optimization model realizes new energy access and dynamic adjustment of output of a traditional generator set, the capability of a power grid to adapt to new energy fluctuation is improved, the utilization efficiency of new energy is maximized, and green transformation of a power system is promoted. The invention further provides a flexible control strategy, the reactive power control requirements of the power distribution network under different regions, scales and operation conditions are met, the effectiveness of the method and the feasibility of engineering application are verified through simulation experiments, and the method has important theoretical significance and application value.

Description

Technical Field

[0001] The present invention relates to the technical field of power system optimization, and in particular to a distribution network reactive power optimization control method, system and medium. Background Art

[0002] With the increasing attention paid to sustainable energy and environmental protection around the world, the widespread application of new energy such as wind and solar energy in power systems has become the key to promoting energy structure transformation and reducing greenhouse gas emissions. However, the volatility and uncertainty of new energy, especially affected by environmental factors such as weather changes, have brought unprecedented challenges to the stability of the power system.

[0003] In this context, the importance of reactive power control has become increasingly prominent. It is not only related to the stability of grid voltage, but also directly affects the stability and power quality of the power system. In the face of the irregularity of renewable energy output, traditional reactive power control methods are no longer sufficient, and innovative control strategies and optimization models are urgently needed. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a reactive power optimization control method for a distribution network, which can quantify the voltage stability level of the power grid by establishing an evaluation index for the voltage support capacity of the distribution network, and provide a decision-making basis for reactive power control. At the same time, the optimization model realizes the dynamic adjustment of the access of new energy and the output of traditional generator sets, improves the ability of the power grid to adapt to the fluctuations of new energy, maximizes the utilization efficiency of new energy, and promotes the green transformation of the power system.

[0005] The present invention also provides a system and a storage medium having the above-mentioned reactive power optimization control method for distribution network.

[0006] According to the first aspect of the present invention, the reactive power optimization control method of the distribution network is characterized by comprising the following steps:

[0007] Evaluate the voltage support capability index of the power grid; wherein the voltage support capability index includes a node voltage deviation index, a voltage margin support index and a reactive power balance margin index;

[0008] According to the voltage support capability index, construct an objective function of a distribution network reactive power optimization model;

[0009] Based on the physical characteristics, operating conditions and safety standards of the power grid, the first constraint condition for power grid operation is established;

[0010] Based on the characteristics of reactive power compensation equipment in the power system, the second constraint condition for power grid operation is constructed;

[0011] Based on the upper limit of renewable energy power output, the third constraint condition for grid operation is established;

[0012] The example information of the power system is used as the input of the reactive power optimization model, and at least one of the first constraint condition, the second constraint condition and the third constraint condition is used as the constraint condition of the reactive power optimization model to solve the reactive power compensation strategy.

[0013] The reactive power optimization control method of the distribution network according to the embodiment of the present invention has at least the following beneficial effects: This application quantifies the voltage stability level of the power grid by establishing an evaluation index for the voltage support capacity of the distribution network, and provides a decision-making basis for reactive power control. At the same time, the reactive power optimization model realizes the dynamic adjustment of the access of new energy and the output of traditional generator sets, improves the ability of the power grid to adapt to the fluctuations of new energy, maximizes the efficiency of new energy utilization, and promotes the green transformation of the power system. The present invention also provides a flexible control strategy to meet the reactive power control needs of distribution networks in different regions, scales and operating conditions, and verifies the effectiveness of the method and the feasibility of engineering application through simulation experiments, which has important theoretical significance and application value.

[0014] According to some embodiments of the present invention, the node voltage deviation indicator L U It is calculated using the following formula:

[0015]

[0016] Among them, U i is the voltage at node i; is the nominal voltage at node i.

[0017] According to some embodiments of the present invention, the voltage margin support indicator L ΔU It is calculated using the following formula:

[0018]

[0019] Where N is the number of nodes in the partition; E i is a measurement variable, U i,min , U i,max are the upper and lower limits of the voltage of the i-th node; τ is the margin factor, the purpose of which is to set a virtual critical safety voltage before the voltage reaches the critical value.

[0020] According to some embodiments of the present invention, the reactive power balance margin indicator L ΔQ It is calculated using the following formula:

[0021]

[0022] Among them, Q L Represents the reactive power demand of load, Q i,GIt represents the maximum reactive power that can be adjusted in normal operation or phase leading operation of the i-th power plant unit or DG, Q i,r Indicates the capacity of each reactive compensation device, Q i,l is the maximum reactive power that each interconnected partition can provide, N g 、N r 、N l They are the number of power sources, the number of reactive power compensation devices and the number of interconnected partitions.

[0023] According to some embodiments of the present invention, the objective function of the power grid reactive power optimization model includes:

[0024] minF=γ1F1+γ2F2+γ3F3

[0025]

[0026] Among them, F is the overall objective function, F1, F2, F3 are sub-objective functions, λ1, λ2, λ3 are weights of sub-objective functions, t is a certain period in the time series, T is the set of time periods, Q L Represents the reactive power demand of load, Q i,G It represents the maximum reactive power that can be adjusted in normal operation or phase leading operation of the i-th power plant unit or DG, Q i,r Indicates the capacity of each reactive compensation device, Q i,l is the maximum reactive power that each interconnected partition can provide, N g 、N r 、N l They are the number of power sources, the number of reactive power compensation devices and the number of interconnected partitions. It represents the node voltage deviation index at time t, U i is the voltage of node i at time t; is the rated voltage of node i, represents the voltage margin support index at time t, is the measurement variable at time t, Represents the reactive power balance margin index at time t.

[0027] According to some embodiments of the present invention, the features of the reactive power compensation device include a number constraint of mechanically switched capacitors and reactive power upper and lower limit constraints of a static VAR compensator.

[0028] According to some embodiments of the present invention, the example information of the power system is used as the input of the reactive power optimization model, and at least one of the first constraint, the second constraint, and the third constraint is used as the constraint of the reactive power optimization model. In the step of solving the reactive power compensation strategy, the JuMP optimization toolkit is used to mathematically model the problem, and then the reactive power optimization model is solved using the CPLEX optimization solver to obtain the optimal reactive power compensation strategy.

[0029] The reactive power optimization control system for a distribution network according to the second aspect of the present invention is characterized by comprising:

[0030] An indicator formulation module, capable of evaluating the voltage support capability indicators of the power grid; wherein the voltage support capability indicators include node voltage deviation indicators, voltage margin support indicators and reactive power balance margin indicators;

[0031] An objective function construction module is capable of constructing a reactive power optimization model of a distribution network according to the voltage support capability index;

[0032] A first constraint module, capable of constructing a first constraint condition for power grid operation based on the physical characteristics, operating conditions and safety standards of the power grid;

[0033] The second constraint module is capable of constructing a second constraint condition for power grid operation based on the characteristics of reactive compensation equipment in the power system;

[0034] The third constraint module can construct the third constraint condition for power grid operation based on the power output upper limit of renewable energy;

[0035] The strategy formulation module can use the example information of the power system as the input of the reactive power optimization model, and use at least one of the first constraint condition, the second constraint condition, and the third constraint condition as the constraint condition of the reactive power optimization model to solve the reactive power compensation strategy.

[0036] According to the terminal of the third aspect embodiment of the present application, the terminal includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, and when the processor executes the computer program, the above-mentioned distribution network reactive power optimization control method is implemented.

[0037] According to a computer-readable storage medium of an embodiment of the fourth aspect of the present invention, the medium stores computer-executable instructions, and the computer-executable instructions are used to execute the above-mentioned distribution network reactive power optimization control method.

[0038] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0040] Figure 1 A schematic diagram of the steps of a reactive power optimization control method for a distribution network according to an embodiment of the present invention;

[0041] Figure 2It is a structural block diagram of a reactive power optimization control system for a distribution network according to an embodiment of the present invention. DETAILED DESCRIPTION

[0042] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0043] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0044] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0045] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0046] With the large-scale access of renewable energy such as wind power and solar energy, the power system faces challenges brought by volatility and uncertainty. In particular, under high penetration, traditional control methods are no longer sufficient to maintain system stability. Aiming at the problem of insufficient stability and voltage support capacity of distribution network under high penetration of new energy, this paper proposes a reactive power control method for distribution network based on multi-objective optimization.

[0047] Embodiment 1

[0048] Reference Figure 1 The embodiment of the present invention provides a method for optimizing reactive power control in a distribution network, the method comprising the following steps:

[0049] Step S100, evaluating the voltage support capability index of the power grid; wherein the voltage support capability index includes a node voltage deviation index, a voltage margin support index and a reactive power balance margin index.

[0050] Step S200: constructing an objective function of a distribution network reactive power optimization model according to the voltage support capability index.

[0051] Step S300: construct the first constraint condition for the operation of the power grid based on the physical characteristics, operating conditions and safety standards of the power grid.

[0052] Step S400: construct a second constraint condition for power grid operation based on the characteristics of reactive power compensation equipment in the power system.

[0053] Step S500: constructing a third constraint condition for grid operation based on the power output upper limit of renewable energy;

[0054] Step S600: Use the example information of the power system as the input of the reactive power optimization model, and use at least one of the first constraint condition, the second constraint condition, and the third constraint condition as the constraint condition of the reactive power optimization model to solve the reactive power compensation strategy.

[0055] Furthermore, in order to describe the purpose and calculation process of the above embodiment in more detail, the above steps are described in more detail.

[0056] Step S100, evaluating the voltage support capability index of the power grid; wherein the voltage support capability index includes a node voltage deviation index, a voltage margin support index and a reactive power balance margin index.

[0057] 1) Node voltage deviation index:

[0058]

[0059] Among them, U i is the voltage at node i; is the rated voltage at node i.

[0060] 2) Voltage margin support indicators:

[0061]

[0062]

[0063] Where N is the number of nodes in the partition; E i is a measurement variable, U i,min , U i,max are the upper and lower limits of the voltage of the i-th node; τ is the margin factor, the purpose of which is to set a virtual critical safety voltage before the voltage reaches the critical value.

[0064] 3) Reactive power balance margin index:

[0065]

[0066] Among them, QL Represents the reactive power demand of load, Q i,G It represents the maximum reactive power that can be adjusted in normal operation or phase leading operation of the i-th power plant unit or DG, Q i,r Indicates the capacity of each reactive compensation device, Q i,l is the maximum reactive power that each interconnected partition can provide, N g 、N r 、N l They are the number of power sources, the number of reactive power compensation devices and the number of interconnected partitions.

[0067] Step S200: constructing an objective function of a distribution network reactive power optimization model according to the voltage support capability index.

[0068] The model uses the above three voltage support capability evaluation indicators as the objective function. Specifically including:

[0069] minF=γ1F1+γ2F2+γ3F3 (5)

[0070]

[0071] Among them, F is the overall objective function, F1, F2, and F3 are sub-objective functions, λ1, λ2, and λ3 are the weights of the sub-objective functions, t is a period in the time series, and T is a set of time periods.

[0072] Step S300: construct the first constraint condition for the operation of the power grid based on the physical characteristics, operating conditions and safety standards of the power grid.

[0073] Grid operation constraints are the cornerstone for ensuring safe, stable and efficient operation of the power system. The grid operation constraints in the present invention include power flow constraints, voltage safety constraints and topology constraints, which are specifically expressed by equations (9) to (16). Power flow constraints ensure the balance between power supply and demand in the power system to prevent overload or insufficient power supply; voltage safety constraints ensure that the voltage of all nodes is maintained within a safe range, protect grid equipment and prevent voltage collapse; and topology constraints involve the physical structure and connection mode of the grid, ensuring that the grid maintains the correct connection and operation mode under various operating conditions.

[0074]

[0075] Among them, i, j, k are the node numbers of the distribution network. is the active power at node j during period t, are the active power flowing from node i to node j and from node j to node k in period t, r ij is the resistance of the line between nodes i and j, It is the square value of the line current between nodes i and j during period t.

[0076]

[0077] in, is the reactive power at node j during period t, are the reactive power flowing from node i to node j and from node j to node k in period t, respectively, ij is the reactance of the line between nodes i and j.

[0078]

[0079] in, is the active power of DG at node j during period t, is the active power of the load at node j during period t.

[0080]

[0081] in, is the reactive power of DG at node j during period t, is the reactive power of the load at node j during period t.

[0082]

[0083] in, is the reactive power of the mechanically switched capacitor at node j during period t, is the reactive power of SVC at node j during period t, N C It is a collection of nodes equipped with reactive power compensation equipment.

[0084]

[0085] Among them, U j,max , U j,min are the upper and lower limits of the voltage at node j.

[0086]

[0087] in, is the square of the voltage at node i.

[0088]

[0089] Among them, l ij,max It is the upper limit of the square value of the line current between nodes i and j.

[0090] These constraints take into account the physical characteristics, operating conditions and safety standards of the power grid, and provide the necessary boundary conditions for the reactive power optimization model of the distribution network. In the optimization process, they are comprehensively considered together with other factors such as reactive compensation equipment constraints and renewable energy constraints to achieve optimal control of reactive power in the distribution network. This approach not only ensures the voltage stability and power balance of the power grid, but also improves the operating efficiency and power supply quality of the power grid, helps the power grid maintain stability and reliability in the face of challenges such as high penetration of renewable energy and load fluctuations, and supports the intelligent and green development of the power system.

[0091] Step S400: construct a second constraint condition for power grid operation based on the characteristics of reactive power compensation equipment in the power system.

[0092] In the power system, reactive power compensation devices play a vital role. They maintain the voltage stability of the power grid and improve the efficiency of power transmission by regulating reactive power.

[0093] The reactive power compensation equipment constraint in the present invention is a key component of the reactive power optimization model of the distribution network, which includes the number constraint of mechanical switching capacitors and the reactive power upper and lower limit constraints of the static VAR compensator (SVC). Mechanical switching capacitors quickly respond to changes in the reactive power demand of the power grid through switching operations, and the number constraint ensures that the number of capacitors used does not exceed the maximum capacity of the system design, avoiding over- or under-compensation. As a dynamic reactive power compensation device, SVC can continuously adjust the reactive power output within a certain range, and its upper and lower limit constraints ensure that the reactive power output does not exceed the designed maximum and minimum values, ensuring that the equipment operates within a safe and effective range.

[0094] These constraints are specifically expressed in the model through equations (17) to (18), and they are comprehensively considered with the grid operation constraints and renewable energy constraints to achieve the optimal control of the reactive power of the distribution network. Through this comprehensive optimization, the present invention not only ensures the voltage stability of the grid, but also improves the utilization efficiency of the reactive compensation equipment, reduces the operating cost, and provides flexible and reliable support for the access of new energy, which is of great significance to the efficient, economical and environmentally friendly operation of the power system.

[0095]

[0096] Among them, Q j,svc,max , Q j,svc,min are the upper and lower limits of the SVC reactive power at node j.

[0097]

[0098] in, is the number of mechanically switched capacitors at node j during period t, N C,maxis the upper limit of the number of mechanical switching capacitors, Q C,step is the reactive power of a single mechanically switched capacitor.

[0099] Step S500: constructing a third constraint condition for grid operation based on the power output upper limit of renewable energy.

[0100] In modern power systems, with the increasing integration of renewable energy sources such as wind and solar energy, they provide a clean and sustainable source of electricity for the power grid. However, the natural volatility and unpredictability of these energy sources also pose challenges to the stability and reliability of the power grid. In order to meet these challenges, the reactive power optimization model of the distribution network of the present invention specifically considers the power output upper limit constraint of renewable energy sources to ensure that the system can maintain efficient and stable operation when integrating these energy sources. Specifically, the power output upper limit constraint ensures that the output of renewable energy at any given point in time does not exceed its technical or physical maximum capacity, preventing equipment damage or grid instability caused by exceeding equipment capacity.

[0101] These constraints are specifically expressed through equations (19) to (20) in the model, which comprehensively consider the current state of renewable energy, weather conditions, equipment capacity and other relevant factors, and define the maximum safe output limit of renewable energy under different operating conditions. By incorporating these renewable energy constraints into the reactive power optimization model, the present invention improves the adaptability of the power grid to the volatility of renewable energy and optimizes the reactive power balance of the power grid. This method not only maximizes the utilization efficiency of renewable energy, but also ensures the stability and voltage quality of the power grid, providing a flexible and sustainable reactive power management strategy for the power system. Ultimately, this reactive power optimization method that comprehensively considers the characteristics of renewable energy is of great significance for promoting the development of the power system in a more green, efficient and intelligent direction, and provides strong technical support for achieving energy transformation and responding to climate change.

[0102]

[0103] Among them, P j,pv,max , P j,pv,min are the upper and lower limits of the PV active power at node j.

[0104]

[0105] Among them, Q j,pv,max , Q j,pv,min are the upper and lower limits of the PV reactive power at node j.

[0106]

[0107] Among them, is the decimal positive integer Convert to binary number, let the total number of digits be The value of the nth bit is For the new variables introduced,

[0108]

[0109] in, For the new variables introduced, M is a sufficiently large number in the big-M method.

[0110]

[0111] Wherein, M is a sufficiently large number in the Big-M method.

[0112]

[0113] in, It is the number of transformer tap positions.

[0114] Step S600: Use the example information of the power system as the input of the reactive power optimization model, and use at least one of the first constraint condition, the second constraint condition, and the third constraint condition as the constraint condition of the reactive power optimization model to solve the reactive power compensation strategy.

[0115] The stable operation of the distribution network and the guarantee of voltage quality are the core tasks of power system management. In the present invention, the distribution network is connected to the upper power grid through the key node 1. The setting of this node has a decisive influence on the voltage stability of the entire power grid. In order to enhance the voltage support capacity of this key node, the present invention adopts the transformer tap voltage regulation technology. By adjusting the tap position of the transformer, the voltage level at the node can be effectively adjusted, thereby improving the voltage stability of the entire distribution network.

[0116] The solution process of this model is the key step to achieve the above goals. Specifically, it includes:

[0117] S601. Taking the calculation information of the distribution network, including detailed data of nodes, branches, loads and power sources, as input, these data provide the necessary system parameters and operating conditions for the model.

[0118] S602: Use the JuMP optimization toolkit to mathematically model the problem. This step converts the actual power system operation problem into a solvable mathematical model, including the setting of the objective function and the expression of the constraint conditions.

[0119] S603, the model is solved using the CPLEX optimization solver. CPLEX is an efficient mathematical programming solver that can handle large-scale linear, integer and mixed integer programming problems. In the present invention, CPLEX is used to solve the established reactive power optimization model and find the optimal reactive power compensation strategy. This strategy is designed to meet the voltage margin and reactive power margin requirements of the distribution network under different operating conditions, while reducing the voltage deviation as much as possible to ensure the voltage quality and system stability of the power grid.

[0120] S604: Output reactive power compensation strategy.

[0121] This calculation process can not only effectively cope with the challenges brought by the high penetration of new energy, but also improve the distribution network's adaptability to new energy fluctuations and voltage support capabilities while ensuring system stability. The implementation of this strategy will further promote the development of the power system in a more intelligent, efficient and sustainable direction.

[0122] Embodiment 2

[0123] Another embodiment of the present application provides a distribution network reactive power optimization control system, the system 20 comprising:

[0124] The indicator formulation module 201 is capable of evaluating the voltage support capability indicator of the power grid; wherein the voltage support capability indicator includes a node voltage deviation indicator, a voltage margin support indicator and a reactive balance margin indicator;

[0125] An objective function construction module 202 is capable of constructing an objective function of a distribution network reactive power optimization model according to the voltage support capability index;

[0126] The first constraint module 203 can construct a first constraint condition for the operation of the power grid based on the physical characteristics, operating conditions and safety standards of the power grid;

[0127] The second constraint module 204 can construct a second constraint condition for power grid operation based on the characteristics of reactive compensation equipment in the power system;

[0128] The third constraint module 205 can construct a third constraint condition for grid operation based on the power output upper limit of renewable energy;

[0129] The strategy formulation module 206 can use the example information of the power system as the input of the reactive power optimization model, and use at least one of the first constraint condition, the second constraint condition, and the third constraint condition as the constraint condition of the reactive power optimization model to solve the reactive power compensation strategy.

[0130] Another embodiment of the present application provides a terminal, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned distribution network reactive power optimization control method when executing the computer program.

[0131] Specifically, the processor may be a CPU, a general-purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, a transistor logic device, a hardware component or any combination thereof. It may implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of this application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0132] Specifically, the processor is connected to the memory via a bus, and the bus may include a path for transmitting information. The bus may be a PCI bus or an EISA bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc.

[0133] The memory can be a ROM or other type of static storage device that can store static information and instructions, a RAM or other type of dynamic storage device that can store information and instructions, or an EEPROM, CD-ROM or other optical disk storage, optical disk storage (including compressed optical disk, laser disk, optical disk, digital versatile disk, Blu-ray disk, etc.), magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited to this.

[0134] Optionally, the memory is used to store the code of the computer program for executing the solution of the present application, and the execution is controlled by the processor. The processor is used to execute the application program code stored in the memory to implement Figure 2 The illustrated embodiment provides the functions of a reactive power optimization control system for a power distribution network.

[0135] Another aspect of the present application provides a computer-readable storage medium storing computer-executable instructions for executing the above-mentioned Figure 1 The reactive power optimization control method of the distribution network is shown.

[0136] The embodiment of the present application establishes an evaluation index for the voltage support capacity of the distribution network, quantifies the voltage stability level of the power grid, and provides a decision-making basis for reactive power control. At the same time, the optimization model realizes the dynamic adjustment of the access of new energy and the output of traditional generator sets, improves the ability of the power grid to adapt to the fluctuations of new energy, maximizes the efficiency of new energy utilization, and promotes the green transformation of the power system. The present invention also provides a flexible control strategy to meet the reactive power control needs of the distribution network in different regions, scales and operating conditions, and verifies the effectiveness of the method and the feasibility of engineering application through simulation experiments, which has important theoretical significance and application value.

[0137] The device embodiments described above are only illustrative, and the units described as separate components may or may not be physically separated, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0138] It will be appreciated by those skilled in the art that all or some of the steps and systems in the disclosed method above may be implemented as software, firmware, hardware and appropriate combinations thereof. Some physical components or all physical components may be implemented as software executed by a processor, such as a central processing unit, a digital signal processor or a microprocessor, or may be implemented as hardware, or may be implemented as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or a non-transitory medium) and a communication medium (or a temporary medium). As known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, disk storage or other magnetic storage devices, or any other medium that may be used to store desired information and may be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically embodies computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0139] The above is a specific description of the preferred implementation of the present application, but the present application is not limited to the above-mentioned implementation mode. Technical personnel familiar with the field can also make various equivalent deformations or substitutions without violating the spirit of the present application. These equivalent deformations or substitutions are all included in the scope defined by the claims of the present application.

Claims

1. A reactive power optimization control method for a distribution network, characterized in that: The following steps are involved: Evaluate the voltage support capability index of the power grid; wherein the voltage support capability index includes a node voltage deviation index, a voltage margin support index and a reactive power balance margin index; According to the voltage support capability index, a distribution network reactive power optimization model is constructed; Based on the physical characteristics, operating conditions and safety standards of the power grid, the first constraint condition for power grid operation is established; Based on the characteristics of reactive power compensation equipment in the power system, the second constraint condition for power grid operation is constructed; Based on the upper limit of renewable energy power output, the third constraint condition for grid operation is established; The example information of the power system is used as the input of the reactive power optimization model, and at least one of the first constraint condition, the second constraint condition and the third constraint condition is used as the constraint condition of the reactive power optimization model to solve the reactive power compensation strategy.

2. The method according to claim 1, characterized in that The node voltage deviation index L U It is calculated using the following formula: Among them, U i is the voltage at node i; is the rated voltage at node i.

3. The method according to claim 1, characterized in that The voltage margin support index L ΔU It is calculated using the following formula: Where N is the number of nodes in the partition; E i is a measurement variable, U i,min , U i,max are the upper and lower limits of the voltage of the i-th node; τ is the margin factor, the purpose of which is to set a virtual critical safety voltage before the voltage reaches the critical value.

4. The method according to claim 1, characterized in that: The reactive power balance margin index L ΔQ It is calculated using the following formula: Among them, Q L Represents the reactive power demand of load, Q i,G It represents the maximum reactive power that can be adjusted in normal operation or phase leading operation of the i-th power plant unit or DG, Q i,r Indicates the capacity of each reactive compensation device, Q i,l is the maximum reactive power that each interconnected partition can provide, N g 、N r 、N l They are the number of power sources, the number of reactive power compensation devices and the number of interconnected partitions.

5. The method according to claim 1, characterized in that The objective function of the power grid reactive power optimization model includes: min F=γ1F1+γ2F2+γ3F3 Among them, F is the overall objective function, F1, F2, and F3 are sub-objective functions, λ1, λ2, and λ3 are weights of sub-objective functions, t is a certain period in the time series, T is the set of time periods, and Q L Represents the reactive power demand of load, Q i,G It represents the maximum reactive power that can be adjusted in normal operation or phase leading operation of the i-th power plant unit or DG, Q i,r Indicates the capacity of each reactive compensation device, Q i,l is the maximum reactive power that each interconnected partition can provide, N g 、N r 、N l They are the number of power sources, the number of reactive power compensation devices and the number of interconnected partitions. It represents the node voltage deviation index at time t, U i is the voltage of node i at time t; is the rated voltage of node i, represents the voltage margin support index at time t, is the measurement variable at time t, It represents the reactive power balance margin index at time t.

6. The method according to claim 1, characterized in that The characteristics of the reactive power compensation equipment include the number constraint of mechanical switching capacitors and the reactive power upper and lower limit constraints of the static reactive power compensator.

7. The method according to claim 1, characterized in that In the step of using the example information of the power system as the input of the reactive power optimization model, and using at least one of the first constraint condition, the second constraint condition, and the third constraint condition as the constraint condition of the reactive power optimization model, and solving the reactive power compensation strategy, the JuMP optimization toolkit is used to mathematically model the problem, and then the reactive power optimization model is solved using the CPLEX optimization solver to obtain the optimal reactive power compensation strategy.

8. A reactive power optimization control system for a distribution network, characterized in that: include: An indicator formulation module, capable of evaluating the voltage support capability indicators of the power grid; wherein the voltage support capability indicators include node voltage deviation indicators, voltage margin support indicators and reactive power balance margin indicators; An objective function construction module is capable of constructing a reactive power optimization model of a distribution network according to the voltage support capability index; A first constraint module, capable of constructing a first constraint condition for power grid operation based on the physical characteristics, operating conditions and safety standards of the power grid; The second constraint module is capable of constructing a second constraint condition for power grid operation based on the characteristics of reactive compensation equipment in the power system; The third constraint module can construct the third constraint condition for power grid operation based on the power output upper limit of renewable energy; The strategy formulation module can use the example information of the power system as the input of the reactive power optimization model, and use at least one of the first constraint condition, the second constraint condition, and the third constraint condition as the constraint condition of the reactive power optimization model to solve the reactive power compensation strategy.

9. A terminal, characterized in that: Said include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method according to any one of claims 1 to 7.

10. A computer-readable storage medium storing computer-executable instructions, wherein the computer-executable instructions are used to execute the method according to any one of claims 1 to 7.

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