Line power flow regulation and control method, system and equipment for power system and medium

Abstract

The invention relates to the technical field of electric power systems, and discloses a line power flow regulation and control method, system and device for an electric power system and a medium, and the method comprises the steps: predicting a reactive power demand target value of the system through collecting operation data of the electric power system after new energy equipment is connected; determining a plurality of target equipment according to the capacity margin of the equipment and the electrical distance between the equipment and the new energy equipment when the value is within the regulation capability range of reactive power flow regulation and control equipment comprising a bypass switch, an LC filter, an H-bridge converter and a direct-current capacitor; building a quadratic programming model based on the reactive power demand target value, solving the model, obtaining a target equipment output strategy, and sending the target equipment output strategy to the corresponding target equipment, so as to control each target equipment to regulate and control the line power flow through a decoupling control technology; and verifying the regulation and control result, if the regulation and control result does not pass the verification, performing incremental correction on the reactive power demand target value, and solving the strategy again until the final verification is passed, thereby realizing effective regulation and control of the line power flow in the power system.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a line flow control method, system, equipment and medium for power systems. Background Art

[0002] In the existing technology, the control method of traditional reactive compensation equipment, such as capacitors and reactors, is relatively simple and independent. They are usually switched on and off according to fixed set values ​​or simple local measurement signals. They lack the ability to perceive and coordinate the global information of the entire power system. As a result, in a complex power grid environment, the adjustment of various devices is difficult to coordinate and cooperate, and over-compensation or under-compensation is prone to occur. It is impossible to accurately meet the dynamic needs of the power system that change with the intermittent and fluctuating access of renewable energy power generation, thereby affecting the stable operation of the power grid and the power quality.

[0003] It can be seen that how to regulate the line flow in the power system so that the system can adapt to the changes in reactive power demand caused by the access of new energy to the power grid has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0004] The present invention provides a line flow control method, system, device and medium for an electric power system, which solves the problem of how to control the line flow in the electric power system so that the system can adapt to the changes in reactive power demand caused by the access of new energy sources to the power grid.

[0005] To solve the above technical problems, the present invention provides a first aspect of a line flow control method for a power system, comprising: Real-time collection of operating data of the power system after the connection of new energy equipment, and prediction of the reactive power demand target value of the power system in a future preset time period based on the operating data; When the reactive power demand target value is within the regulation capacity constraint range of the reactive power flow control device, multiple target devices are determined based on the capacity margin of the reactive power flow control device and the electrical distance between the reactive power flow control device and the new energy device; the reactive power flow control device includes a bypass switch, an LC filter, an H-bridge converter, and a DC capacitor; A quadratic programming model is constructed and solved according to the reactive power demand target value to obtain a target device output strategy and send it to the corresponding target device, so as to control each target device to regulate the line power flow through a decoupling control technology; Acquiring actual power data of the power system after power flow control of each target device line, and calculating the deviation between the actual power data and the reactive power demand target value; When the deviation exceeds the preset deviation threshold, the reactive power demand target value is incrementally corrected, and the target device output strategy generation process is iteratively executed according to the corrected reactive power demand target value until the actual power data finally obtained does not exceed the preset deviation threshold, so as to realize the regulation of the line flow in the power system.

[0006] A second aspect of the present invention provides a line flow control system for a power system, comprising: A target prediction module is used to collect real-time operating data of the power system after the new energy equipment is connected, and to predict the reactive power demand target value of the power system in a preset time period in the future based on the operating data; an equipment selection module for determining, when the reactive power demand target value is within the regulation capacity constraint range of the reactive power flow control device, a plurality of target devices based on the capacity margin of the reactive power flow control device and the electrical distance between the reactive power flow control device and the new energy device; the reactive power flow control device includes a bypass switch, an LC filter, an H-bridge converter, and a DC capacitor; A power flow control module is used to construct and solve a quadratic programming model based on the reactive power demand target value, obtain a target device output strategy, and send it to the corresponding target device to control each target device to control the line power flow through decoupling control technology; a deviation calculation module, configured to obtain actual power data of the power system after power flow control of each target device line, and calculate a deviation between the actual power data and the reactive power demand target value; An iterative control module is used to incrementally correct the reactive power demand target value when the deviation exceeds a preset deviation threshold, and iteratively execute the target equipment output strategy generation process according to the corrected reactive power demand target value until the actual power data finally obtained does not exceed the preset deviation threshold, so as to realize the control of the line flow in the power system.

[0007] A third aspect of the present invention provides an electronic device comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, the line flow control method for the power system as described above is implemented.

[0008] A fourth aspect of the present invention provides a computer-readable storage medium, which includes a stored computer program, wherein when the device where the computer-readable storage medium is located executes the computer program, the line flow control method for the power system as described above is implemented.

[0009] Compared with the prior art, the embodiments of the present invention have the following advantages: (1) By collecting and analyzing the operating data of the power system after the connection of new energy equipment in real time, it is possible to accurately predict the future reactive power demand target value and formulate a reactive power flow control strategy based on it. In addition, when formulating the strategy, the regulation capacity constraints, capacity margin and electrical distance of the reactive power flow control equipment are comprehensively considered to ensure the effectiveness and feasibility of the control strategy; (2) Through decoupling control technology, each target device can independently and accurately control the line flow, achieving coordinated output of multiple reactive power flow control devices and improving the stability and operating efficiency of the power system. At the same time, the scheme also has self-correction capabilities. It can make incremental corrections to the reactive power demand target value based on the deviation between the actual power data and the reactive power demand target value, and iteratively execute the control strategy until the preset control accuracy is achieved, thereby achieving precise control of the line flow in the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are only some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0011] Figure 1 This is a flow chart of a method for controlling line flow in a power system provided by one embodiment of the present invention; Figure 2 This is a topological diagram of a reactive power flow control device provided by an embodiment of the present invention; Figure 3 This is a main circuit diagram of a reactive power flow control device provided by a certain embodiment of the present invention; Figure 4 is an equivalent circuit diagram of a reactive power flow control device provided by a certain embodiment of the present invention; Figure 5 This is a block diagram of a voltage outer loop control provided by an embodiment of the present invention; Figure 6 This is a block diagram of the current inner loop control provided by an embodiment of the present invention; Figure 7 This is a structural diagram of a line flow control system for a power system provided by an embodiment of the present invention; Figure 8 This is a structural diagram of an electronic device provided by one embodiment of the present invention; Reference numerals: Among them, 1. Reactive power flow control equipment; 2. Bypass switch; 3. LC filter; 4. H-bridge converter; 5. DC capacitor; 6. Inductor; 7. External access equipment; 8. Transformer; 10. Target prediction module; 20. Equipment selection module; 30. Power flow control module; 40. Deviation calculation module; 50. Iterative control module; 5000, electronic equipment; 5001, processor; 5002, bus; 5003, memory; 5004, transceiver. DETAILED DESCRIPTION

[0012] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings and embodiments. Obviously, the embodiments described are only some embodiments of the present invention, rather than all embodiments. The purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0013] In the description of this application, the terms "first," "second," "third," etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first," "second," "third," etc. may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0014] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be a communication between the two components. The terms "vertical", "horizontal", "left", "right", "up", "down" and similar expressions used herein are for illustrative purposes only, and do not indicate or imply that the system or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0015] In the description of this application, it should be noted that, unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by those skilled in the art. The terms used in this specification are only for describing specific embodiments and are not intended to limit the present invention. Those skilled in the art will understand the specific meanings of the above terms in this application according to specific circumstances.

[0016] Currently, with the expansion of power systems and the increasing complexity of loads, reactive power flow control faces numerous challenges. On the one hand, line impedance leads to significant reactive power transmission losses, and regional variations in reactive power demand lead to irrational power flow distribution, resulting in voltage fluctuations and restricted active power transmission. On the other hand, traditional reactive power compensation equipment has a single adjustment method and slow response, and switching easily generates inrush currents, making it difficult to meet the requirements of fast and precise control. Furthermore, the integration of new energy equipment causes frequent changes in the system's reactive power demand, which in turn affects the grid's voltage stability and power quality.

[0017] Based on this, in one embodiment, if Figure 1 As shown, the first aspect of the present invention provides a line flow control method for a power system, comprising: S1. Real-time collection of operating data of the power system after access to new energy equipment, and prediction of a reactive power demand target value of the power system within a future preset time period based on the operating data; In one embodiment, step S1 includes: collecting in real time the output power, line flow data, and equipment operating status data of the power system after the new energy equipment is connected, as the operating data; The operating data is processed based on a sliding time window or a pre-trained long short-term memory network to predict the reactive power demand change trend of the power system in a future preset time period and obtain a reactive power demand target value.

[0018] Specifically, after the new energy equipment is connected to the power system through the transmission line, multiple reactive power flow control devices 1 are installed at the connection point between the new energy equipment and the system. It should be noted that the functions and structures of the various reactive power flow control devices connected to the power system are the same and can all be referred to as reactive power flow control devices 1. The topological structure of the reactive power flow control device 1 used in the present invention is as follows: Figure 2As shown, it includes a bypass switch 2, an LC filter 3, an H-bridge converter 4, and a DC capacitor 5. Multiple devices are deployed in series in the power system. All reactive power flow control devices 1 are considered as a whole - a series device group. Then, external access devices 7 (that is, loads and new energy devices, such as wind turbines, photovoltaic units, etc.) are set at both ends of the series device group and connected to the series device group through a transformer 8. In addition, an inductor 6 is deployed at the input end of the series device group and connected to the output end of the external access device 7. The main circuit of the reactive power flow control device 1 is as follows Figure 3 As shown, in Figure 3 middle, is the voltage of the left access point to ground; is the voltage of the right access point to ground; is the equivalent internal resistance of the series access side; 、 are the filter inductance and DC capacitance of the reactive power flow control device 1 respectively; is the current flowing into the grid side; is the current flowing through the H-bridge converter 4 after being filtered by the LC filter 3; is the inverter voltage on the AC side; is the capacitor voltage of the reactive power flow control device 1.

[0019] The working principle of the reactive power flow control device 1 is to control the on and off of the IGBT switching devices in the upper and lower arms of the single-phase full bridge, so that it outputs an equivalent voltage phasor with controllable amplitude and phase, which is filtered by the LC filter 3 and input into the line through the single-turn coupling transformer. Therefore, the reactive power flow control device 1 can be equivalent to a controlled voltage source connected in series on the line, thereby completing the control of the line flow. Among them, the equivalent circuit of the reactive power flow control device 1 connected to the power system is as follows Figure 4 As shown, it is a dual power supply system, and the voltage amplitude at the first end is , the phase angle is The terminal voltage amplitude is , the phase angle is ; The equivalent impedance of the line is ; is the equivalent output voltage; is the transmission line current amplitude, and the initial phase angle is set to 0°.

[0020] When the reactive power flow control device 1 is connected to the power system and is in operation, the transmission line current is: Then, when the reactive power flow control device 1 is not connected to the system or is not running, ignoring the line resistance, the line current amplitude is: Where, is the transmission line current; , is the phase angle difference of the voltage at the first and last ends.

[0021] Since the line current phase angle is set to 0° and the equipment loss is ignored, we have: It can be seen that the connection of the reactive power flow control device 1 only changes the amplitude of the controlled line current but does not change its phase. Hysteresis , that is, when the equivalent output capacitive voltage is , the line current increases, and the line transmission power increases, but the maximum increase in line transmission power depends on the equipment capacity and line transmission capacity. Ahead , that is, when the equivalent output inductive voltage is , the line current decreases and the line transmission power decreases. , the line current is zero, the voltage on the line impedance is also zero, and the line transmission power is zero; when At this time, the line current is reversed and the line flow is reversed. Therefore, the reactive power flow control device 1 can realize flow control and flow reversal, and realize flexible transmission of line flow value and direction within a certain range.

[0022] Therefore, the reactive power flow control device 1 is connected to the system and injected into the system. The apparent power at the head end of the transmission line is for: Furthermore, the apparent power at the end of the transmission line for: Then, based on the apparent power at the beginning and end of the transmission line, the active power at the beginning and end of the line can be determined as: Where, P A 、P B are the active power at the beginning and end of the line respectively.

[0023] According to the apparent power at the beginning and end of the transmission line, the reactive power at the beginning and end of the line can be determined as: Where Q A , Q B are the reactive power at the beginning and end of the line respectively.

[0024] Then, after the reactive power flow control device 1 is put into operation, the changes in the active power of the line and the reactive power at the head and end are: Where, is the change in active power of the line; 、 are the changes in reactive power at the beginning and end of the line respectively.

[0025] The difference in reactive power between the ends of a transmission line for: Furthermore, the reactive power loss caused by the equivalent impedance of the transmission line for: Reactive power injected into the transmission line by reactive power flow control device 1 for: It can be seen that the reactive power flow control device 1 changes The size and phase of the reactive power injected into the line can be changed, and the active power at both ends of the line can also be regulated, that is, the power flow regulation of the line can be achieved.

[0026] When fluctuations in renewable energy power cause a sudden change in reactive power demand, the output power of the power system (that is, the active power and reactive power of the renewable energy equipment), line flow data (current, voltage), and equipment operating status data (operating status information of key equipment such as transformers, circuit breakers, capacitors, etc., including equipment temperature, pressure and other parameters) are collected in real time as operating data.

[0027] Then, based on the characteristics of the power system and the cycle of reactive power demand changes, determine the appropriate time window size, such as 15 minutes, 30 minutes or 1 hour. Slide the time window on the operating data at a certain step size (such as 1 minute). After each slide, perform statistical analysis on the data in the current time window, and calculate statistical quantities such as the average, maximum, minimum, and standard deviation to extract features related to reactive power demand, such as the rate of change of output power, fluctuations in line flow, and changing trends in equipment operating status. Use time series analysis methods (such as exponential smoothing and ARIMA models) to analyze the extracted features, and then predict the reactive power demand changing trend of the power system in the future preset period (the next 5 to 10 seconds) to obtain the reactive power demand target value.

[0028] The collected operating data can also be preprocessed, including data cleaning and normalization, and then converted into a format suitable for LSTM model input and input into the LSTM model trained with historical operating data, so that the model can output the reactive power demand change trend of the power system in the next 5 to 10 seconds and obtain the reactive power demand target value.

[0029] The present invention collects and analyzes operating data in real time to predict the changing trend of reactive power demand, and can timely adjust the reactive compensation device of the power system to prevent voltage fluctuations and power factor degradation caused by insufficient or excessive reactive power, thereby ensuring the safe and stable operation of the power system; accurately predicting the target value of reactive power demand helps to reasonably allocate reactive resources, avoid over-compensation or insufficient reactive power, improve the operating efficiency of the power system, and reduce operating costs; by real-time monitoring and prediction of changes in reactive power demand, the power system can quickly respond to fluctuations in renewable energy power generation and improve its ability to absorb new energy.

[0030] S2. When the reactive power demand target value is within the regulation capacity constraint range of the reactive power flow control device, determining multiple target devices according to the capacity margin of the reactive power flow control device and the electrical distance between the reactive power flow control device and the new energy device; Specifically, determine whether the reactive power demand target value is within the regulation capacity constraint range of the reactive power flow control device (i.e., the reactive power output range of the reactive power flow control device 1). If it meets the constraint range, enter the target device selection process; otherwise, compress the demand proportionally to adjust it to within the constraint range, and then enter the target device selection process.

[0031] In one embodiment, the determining of the plurality of target devices based on the capacity margin of the reactive power flow control device and the electrical distance between the reactive power flow control device and the new energy device includes: Obtaining the capacity margin of the reactive power flow control device, and determining the electrical distance between the reactive power flow control device and the new energy device according to the impedance modulus or electrical coupling of the reactive power flow control device; Normalizing the capacity margin and the electrical distance, and performing weighted summation on the normalized results to obtain a priority weight of the reactive power flow control device; Based on the priority weights, the reactive power flow control devices are sorted from high to low to construct a regulation queue; According to the reactive power demand target value, a number of target devices are selected from the adjustment queue in a weighted ratio.

[0032] Specifically, the present invention takes the difference between the maximum reactive power output of the reactive power flow control device 1 and the current reactive power output value of the reactive power flow control device 1 obtained, that is, the current remaining adjustable reactive power of the device as the capacity margin of the reactive power flow control device 1 and obtains it; calculates the impedance modulus of the line between the reactive power flow control device 1 and the new energy device, and takes the inverse of the impedance modulus as the electrical distance between the two, or calculates the electrical coupling degree between the reactive power flow control device 1 and the new energy device (such as the sensitivity of the node admittance matrix), and takes the absolute value of the differential result of the coupling degree as the electrical distance between the two.

[0033] Both the capacity margin and the electrical distance are normalized to become dimensionless values ​​of 0~1, and then the two normalized results are weighted and summed to obtain the priority weights of each reactive power flow control device 1; wherein, the sum of the capacity margin weight and the electrical distance weight is 1. Preferably, the capacity margin weight is 0.7 to emphasize the responsiveness, and the electrical distance weight is 0.3 to emphasize the control efficiency.

[0034] According to the calculated priority weight, the reactive power flow control device 1 is sorted from high to low to form a regulation queue. According to the reactive power demand target value, the regulation task is allocated in proportion to the priority weight, that is, the reactive power compensation amount of the device. A greedy algorithm can be used to call the devices in sequence until the demand is met. If the device regulation amount exceeds its margin, it is marked as fully loaded and the remaining demand is reallocated to the suboptimal device. Finally, several target devices and their assigned reactive power compensation amounts are determined.

[0035] The present invention selects the optimal equipment for reactive power compensation through a comprehensive assessment of electrical distance and capacity margin, thereby improving control efficiency. Normalization processing and a weighted summation mechanism enable the solution to flexibly adapt to different system scenarios, ensuring that the adjustment priority is scientific and reasonable. Target equipment is selected according to the weight ratio to ensure the rapid stabilization of key lines, avoid resource waste, and maximize the reactive power compensation effect.

[0036] S3. Constructing and solving a quadratic programming model based on the reactive power demand target value to obtain a target device output strategy and sending it to the corresponding target device to control each target device to regulate the line power flow through a decoupling control technology; In one embodiment, constructing and solving a quadratic programming model based on the reactive power demand target value to obtain a target device output strategy includes: Obtaining loss data, output voltage, and usage capacity of each target device to construct an operation function of each target device using a Lagrangian method; Collecting the real-time power flow value of the controlled line of each target device, and using the sum of squares of errors between the real-time power flow value and a given reference value as the optimization function of each target device; Constructing a device quantity variable function according to the number of the target devices, and constructing a planning sub-model for each of the target devices based on the reactive power demand target value through each of the operation functions, each of the optimization functions, and the device quantity variable function; The planning sub-models are integrated to generate a quadratic programming model, and the quadratic programming model is solved by calling the interior point solver under preset constraints to obtain the output voltage amplitude and phase distribution of each target device as the output strategy output of the target device.

[0037] Specifically, during the system-level control process, the present invention obtains information such as loss data, output voltage (e.g., rated voltage, actual operating voltage), and usage capacity (e.g., rated capacity, current usage capacity) of each target device in real time from the power system monitoring system. The Lagrangian method is used to take factors such as the device's loss data, output voltage, and usage capacity into consideration to construct an operating function for the target device, which is expressed as follows: Where, 、 、 、 are the operation function, loss function, device output voltage, and usage capacity evaluation function of the i-th target device, respectively; the loss function represents the total power loss of the i-th target device during operation, including resistance loss, switching loss, and harmonic loss; R se is the equivalent series resistance of the target device (including the filter inductor resistance and the H-bridge converter on-resistance); i se2,i is the filtered effective value of the current flowing through the i-th target device; f sw is the switching frequency of the H-bridge converter; E on 、E off is the turn-on and turn-off energy loss of a single IGBT device; I h,i , Z h,i are the effective value of the hth harmonic current and the corresponding harmonic impedance, respectively; α, β, and γ are weight coefficients used to balance the contributions of different loss terms. The weight coefficients are dynamically generated through a multi-factor optimization model based on equipment operating status parameters and historical performance data, where α corresponds to the conductor loss weight, β is related to the operating conditions of the switching devices, and γ reflects the harmonic suppression requirements; λ is the number of target devices; is the injection voltage of the i-th target device into the line, which can also be understood as the output voltage of the device; 、 are the rated output voltage and rated capacity of the i-th target device respectively; is the usage capacity of the i-th target device. Among them, the loss function The dimensions of each item in the formula are exactly the same, all in watts (W), which is the unit of power loss. First, the first item in the formula represents the conductor loss, where resistance (Unit: Ohm) and the square of the current (Unit: Ampere²) multiplied by the result is Ω A 2 =W, which directly corresponds to the Joule heat loss in the power system. Describing switching losses: switching frequency (Unit: Hertz Hz, i.e. number of switches per second) and single switching energy (unit: joule J) product, converted to (1 / s) J=J / s=W, which reflects the total power loss of high-frequency switching operation in the time domain. Its physical mechanism originates from the dynamic switching characteristics of power electronic devices. Finally, the third harmonic loss In the current square (A²) vs. Impedance The product of (Ω) also gives A 2 Ω=W.

[0038] In addition, the constraints for running the function for: Where, is the equation operation constraint condition of the i-th target device, including the total injection voltage equation constraint; is the inequality operating constraint condition of the i-th target device, including single device output constraint, transformer voltage constraint, transformer capacity constraint, and line flow constraint; 、 are the lower and upper bounds of the inequality constraints, respectively.

[0039] The power flow data (active power and reactive power) of the controlled lines of each target device is collected in real time, and the sum of the squares of the errors between the real-time power flow value and the given reference value is used as the optimization objective function to minimize the power flow error. A device quantity variable function is then constructed based on the number of target devices in operation, taking into account the impact of the device combination on the reactive power compensation effect, so that the reactive power compensation of the target device meets the reactive power demand target value. Based on the reactive power demand target value, the operation function, optimization function, and device quantity variable function are integrated to construct a planning sub-model for each target device. For the reactive power compensation demand in a certain area, the model considers the reactive power compensation effect and cost under different device combinations and optimizes the output strategy of each device through the sub-model. The planning sub-model is represented by the following formula: Where, Planning sub-model for the i-th target device; 、 They are real-time value of the flow and given reference value respectively; It is a function of the number of equipment variables, and can also be understood as an additional term related to the number of equipment, used to quantify the impact of the input quantity of target equipment on economic efficiency or resource utilization; The input quantity of the target equipment; It is the full life cycle cost of a single target device (including purchase, installation, and operation and maintenance costs).

[0040] By integrating the planning sub-models of each target device, a quadratic programming model can be generated, which is expressed as follows: Finally, under the preset constraints, the quadratic programming model is solved by calling the interior point solver to obtain the output voltage amplitude and phase distribution of each target device as the output strategy of the target device.

[0041] By constructing and solving a quadratic programming model, the present invention can accurately formulate the output strategy of the target equipment according to the reactive power demand target value, ensure the reactive power balance of the power system, and improve the stability and reliability of the power system; the system-level control process can comprehensively consider multiple factors such as the total injection voltage required for line flow regulation, line flow constraints, single device output limitations, and transformer-related constraints, to achieve coordinated work of multiple reactive flow regulation devices, thereby more reasonably optimizing the active and reactive flows of the line; using the square sum of the errors between the real-time value of the flow and the given reference value as the optimization function, the operation of the target equipment can be made as close to the ideal state as possible, the flow error can be reduced, and the operating efficiency of the power system can be improved; by constructing a device quantity variable function and combining it with the reactive power demand target value, the number of target devices can be reasonably configured on the premise of meeting the reactive power demand, avoiding equipment redundancy or shortage, and improving the economy of the power system.

[0042] In one embodiment, the preset constraints include: The output constraint of a single device is expressed as follows: Where k is the efficiency constraint coefficient, which is 0.8.

[0043] Transformer voltage constraint, which is expressed by: Where, It is the maximum value of the voltage injected into the transmission line by the reactive power flow control device 1.

[0044] Transformer capacity constraint, which is expressed by the following formula: Where, is the rated power of the single-turn coupling transformer between the reactive power flow control device 1 and the transmission line.

[0045] Also included is the total injection voltage constraint, which is expressed as: Wherein, n is the number of reactive power flow control devices 1.

[0046] Line power flow constraint, which is expressed by the following formula: Where, and They correspond to the minimum and maximum values ​​of the active and reactive power of the controlled line respectively; They correspond to the minimum and maximum current of the controlled circuit respectively; 、 are the currents corresponding to the reactive power of the controlled lines.

[0047] The method of solving the quadratic programming model by calling an interior point solver under preset constraints to obtain the output voltage amplitude and phase distribution of each target device as the output strategy of the target device includes: Under the preset constraints, the quadratic programming model is solved once by calling an interior point solver to obtain the initial output voltage amplitude and phase distribution of each target device; If the initial output voltage amplitude and phase distribution do not satisfy the single device output constraint or the transformer capacity constraint, adjusting the transformer voltage constraint to form a transformer voltage soft constraint; Using the square of the transformer voltage soft constraint as a penalty term, and updating the quadratic programming model based on the penalty term to obtain a quadratic programming target model; Under the single device output constraint, the transformer capacity constraint and the transformer voltage soft constraint, the quadratic programming target model is solved quadratically by calling the interior point solver to obtain the output voltage amplitude and phase distribution of each target device as the output strategy output of the target device.

[0048] Specifically, under preset constraints, the present invention calls an interior point solver (such as CPLEX, Gurobi, etc.) to solve the quadratic programming model once to obtain the initial output voltage amplitude and phase distribution of each target device; checks whether the initial output voltage amplitude and phase distribution exceed the device output range. If they are not satisfied, it can also be understood that the model has no solution. By adjusting the transformer voltage constraint, such as adjusting the local voltage fluctuation limit from ±2% to ±3%, or expanding the voltage limit, etc., a transformer voltage soft constraint is formed; then the square of the transformer voltage soft constraint is used as a penalty term, and the penalty term is added to the quadratic programming model to update it, thereby obtaining the quadratic programming target model.

[0049] The transformer voltage soft constraint is used to replace the original transformer voltage constraint under the preset constraint conditions to form a new constraint. Under the new constraint, the updated quadratic programming target model is solved secondary by calling the interior point solver to obtain the output voltage amplitude and phase distribution of each target device. The strategy is checked again and, after passing the check, it is used as the target device output strategy and output to each target device so that each target device adjusts the controlled line power flow according to the received strategy. Otherwise, the output strategy of each objective function is re-solved according to the constraint adjustment method until the calculated strategy meets the constraint.

[0050] By solving the quadratic programming model, the present invention can obtain the optimal output voltage amplitude and phase distribution of each target device under various constraints, thereby formulating a reasonable target device output strategy and improving the operating efficiency and stability of the energy system; the introduction of transformer voltage soft constraints and penalty term mechanism enables the model to be dynamically adjusted and re-solved when the initial solution results do not meet certain constraints, thereby enhancing the algorithm's adaptability to complex constraints; the interior point method solver has high solution accuracy and efficiency when processing quadratic programming problems, and can quickly find the optimal solution that meets the constraints, providing a reliable decision-making basis for the operation of the actual system.

[0051] In one embodiment, controlling each of the target devices to regulate the line power flow through a decoupling control technology includes: Constructing a loop model of each target device in the abc three-phase stationary coordinate system, and performing a single-phase Park transform on each loop model to obtain a voltage model and a current model of each target device in a two-phase synchronous rotating coordinate system; Introducing intermediate variables into each of the voltage models to perform cross-decoupling to obtain a decoupling model of each of the target devices, and processing each of the decoupling models through a PI controller to obtain a reference voltage value of each of the target devices; Processing each of the current models using Park transformation and feedforward decoupling method to obtain a current processing model of each of the target devices, and processing each of the current processing models using a PI controller to obtain a reference current value of each of the target devices; Based on each of the reference voltage values ​​and each of the reference current values, a modulation signal is generated for the H-bridge converter 4 in each of the target devices, and each of the bypass switches 2 is controlled according to each of the modulation signals to obtain an equivalent voltage phasor to control each of the target devices to regulate the line flow.

[0052] Specifically, in the device-level control process, the present invention maintains the voltage stability of the DC capacitor 5 of the reactive power flow control device 1 itself and performs power flow control. The control quantity is the modulation ratio of the single-phase H bridge. and trigger phase angle , to construct the loop model of the target device in the abc three-phase stationary coordinate system, which is expressed by the following formula: Where, Connect the voltage difference on both sides of the access point in series to the target device.

[0053] In order to realize the single-phase coordinate transformation, the hysteresis of the original variable is constructed. The new variable, assuming is the original variable, To lag behind variables, is the directional phase, then: Where, 、 are the new variables and their lags, respectively. variables.

[0054] The voltage outer loop control block diagram is as follows Figure 5 As shown, it should be noted that Figure 5 All unmarked calculation units in the default value are added. Performing a single-phase Park transform on the loop model of each target device can obtain the voltage model and current model of the corresponding target device in the two-phase synchronous rotating coordinate system, which can be expressed as follows: Where, Connect the target device to the voltage difference on both sides of the access point; is the grid-side frequency; 、 i se2 The q-axis and d-axis components in the synchronously rotating coordinate system; 、 i se1 The q-axis and d-axis components in the synchronously rotating coordinate system.

[0055] According to the voltage model, by It is also affected by the output voltage In order to facilitate control, cross decoupling is performed and intermediate variables are introduced. , and obtain the decoupling model of each target device, which is expressed by the following formula: in, thus, The decoupling between the d-axis and q-axis components of the current has been achieved, and the PI controller can be used to process the decoupling models to obtain the reference voltage value of each target device. 、 , which is represented by the following formula: in, 、 are proportional and integral coefficients respectively; 、 They are 、 The reference value is generated by the voltage outer loop control strategy.

[0056] The current inner loop control block diagram is as follows Figure 6 As shown, similarly, Figure 6 In the current inner loop, the present invention adopts the control method of current state feedback combined with voltage feedforward compensation to perform Park transformation on each current model. There is also a coupling relationship between the d-axis and q-axis components of , so feedforward decoupling is adopted, and: Where, 、 are proportional and integral gains respectively; 、 They are The d and q axis components 、 The former is generated by the DC capacitor voltage loop, and the latter is specified according to the voltage control requirements.

[0057] The current processing model of each target device can be obtained, which is expressed by the following formula: By processing each current processing model through the PI controller, the reference current value of each target device can be obtained 、 ; According to the reference voltage value and the reference current value, a suitable modulation strategy (such as PWM modulation) is adopted to generate a modulation signal for the H-bridge converter 4, and then the on-off state of the bypass switch 2 contained therein is controlled according to the modulation signal of each target device, thereby changing the output voltage and current of its own H-bridge converter 4, and obtaining an equivalent voltage phasor with adjustable amplitude and phase to control each target device to regulate the line flow.

[0058] The ultimate goal of the voltage loop control of the reactive power flow control device 1 is to maintain the voltage stability of its own DC capacitor 5 and the output voltage of the tracking device. Only when the voltage control of the DC capacitor 5 is stable can the device work reliably. The stability of the capacitor voltage requires the support of active power, that is, the capacitor voltage is strongly correlated with the d-axis component of the grid-side injected voltage, and then the d-axis component is given by controlling the capacitor voltage.

[0059] The device-level control process adopted in the present invention focuses on maintaining the voltage stability of the device's own DC capacitor 5. By constructing a precise mathematical model and adopting advanced decoupling control technology, the control accuracy and response speed are improved, ensuring that the device can operate reliably under various working conditions, which greatly improves the accuracy and stability of reactive power flow regulation; by generating a modulation signal and controlling the bypass switch 2, the output of the target device can be flexibly adjusted to adapt to different operating conditions and demand changes; the PI controller is used to process the decoupling model and the current processing model, which can achieve precise control of the output voltage and current of the target device, and improve the control accuracy and response speed.

[0060] S4. Obtain actual power data of the power system after power flow control of each target device line, and calculate the deviation between the actual power data and the reactive power demand target value; wherein the actual power data is the active and reactive power of the line.

[0061] S5. When the deviation exceeds a preset deviation threshold, incrementally correct the reactive power demand target value, and iteratively execute the target device output strategy generation process according to the corrected reactive power demand target value until the actual power data finally obtained does not exceed the preset deviation threshold, thereby achieving regulation of the line flow in the power system; Specifically, when the deviation exceeds the preset deviation threshold, the correction process is triggered. The reactive power demand target value is proportionally corrected according to the deviation direction (positive / negative) and amplitude, and the output strategy of each device is recalculated based on the corrected reactive power demand target value until the deviation converges.

[0062] To address the problem of irrational reactive power flow distribution caused by differences in line impedance and regional load characteristics, the present invention precisely controls the equivalent voltage phasor output by the reactive power flow control device 1 to achieve precise regulation of the line current amplitude. This allows for flexible increase or decrease of line transmission power according to actual needs, optimizes power flow distribution, and reduces reactive power loss during transmission. This effectively improves line voltage fluctuations, enhances the operational stability of power equipment, improves grid transmission efficiency, and reduces power transmission costs. Addressing the shortcomings of traditional reactive power compensation equipment, which suffer from a single adjustment mode, slow response speed, and the tendency to generate inrush currents during switching, the control strategy proposed in the present invention enables rapid and precise control of reactive power flow. The designed reactive power flow control device 1 can track changes in system reactive power demand in real time, rapidly adjust output, and avoid adversely affecting system stability during the adjustment process, thus ensuring reliable system operation. Given the challenges posed by the intermittent and fluctuating nature of renewable energy generation to control reactive power flow in the power grid, the present invention optimizes the control strategy to enable the reactive power flow control device 1 to work in tandem with renewable energy generation, stabilize system voltage, suppress power oscillations, and ensure safe and reliable operation of the power system even with the large-scale integration of renewable energy. In order to solve the problems of regulation conflicts and resource waste caused by the independent operation of various reactive compensation devices in the existing power system and the lack of a coordination mechanism, the present invention realizes the coordinated output of multiple reactive power flow control devices 1 from multiple perspectives such as system condition constraints, regulation demand and device utilization rate. Through optimized control, the efficiency of each device is fully utilized, and the global optimization of the active and reactive power flows of the line is achieved, thereby improving the economic operation level and power supply reliability of the power system.

[0063] In one embodiment, the method further comprises: Determining a DC voltage according to the working requirements of the reactive power flow control device and the voltage of the access point of the new energy device, and determining a ripple current based on the circuit topology of the reactive power flow control device; determining a capacitance value of the DC capacitor 5 based on the DC voltage and the ripple current; The normalized LPF is subjected to cutoff frequency conversion and characteristic impedance conversion processing to determine the parameters of the LC filter 3; wherein the normalized LPF is configured to have an impedance of 1 And the cutoff frequency is Hz LPF.

[0064] Specifically, in the process of line power flow control, the parameter design of the reactive power flow control equipment used is crucial, as it can directly affect the equipment performance and system operation. The present invention determines the DC voltage that the DC capacitor 5 can withstand based on the operating requirements of the reactive power flow control equipment (i.e., its rated voltage and voltage regulation margin) and the voltage at the access point of the new energy device. , so that it matches the AC voltage at the access point and the required compensation capacity. Considering that the power of new energy equipment fluctuates frequently after access, the reactive power compensation demand changes greatly. According to the reactive power demand target value Q of the system, the formula is used to calculate Preliminary estimate of capacitance value, where , f is the system frequency. To suppress the DC side voltage ripple, the allowable ripple voltage amplitude is 1%-5% of the DC voltage. The DC side ripple current is calculated based on the estimated capacitance value, system frequency and ripple voltage amplitude. The ripple current on the DC side can also be calculated based on the working principle and circuit topology of the reactive power flow control device. The appropriate capacitor can be selected based on its ripple current tolerance, and the capacitor value can be estimated using the ripple current and allowable ripple voltage. The calculation process is expressed as follows: To ensure stable operation of the equipment under various working conditions, based on the calculated capacitance value, take 1.2-1.5 times the calculated value as the final capacitance value.

[0065] In addition, the present invention adopts a method based on normalized LPF (Low Pass Filter) to design the parameters of LC filter 3. First, the cutoff frequency of the normalized LPF is transformed to change its parameters, and then the characteristic impedance is transformed to obtain the parameters of LC filter 3. The normalized LPF is configured to have an impedance of 1. And the cutoff frequency is Hz LPF. The transformation process of the normalized LPF is expressed as follows: Where, is the component parameter value of the normalized LPF; are the component parameters of LC filter 3.

[0066] Finally, according to the output signal characteristics of new energy equipment such as wind farms, LC filters are generally required to have a characteristic impedance of 3 The cutoff frequency is 30-70, and 6-8 times of the output signal frequency, so as to optimize the filtering effect, reduce the impact of harmonics on the system, and ensure the power quality of the grid.

[0067] In selecting the parameters of the DC capacitor 5, the present invention comprehensively considers multiple factors such as the equipment operating requirements, system voltage level, compensation capacity requirements, ripple current and voltage ripple, and enhances the reliability of equipment operation by reserving a certain safety margin. In the parameter design of the LC filter 3, a method based on normalized LPF is adopted to simplify the design process, while more effectively improving the filtering performance, reducing the impact of harmonics on the system, and ensuring the power quality of the power system.

[0068] In the embodiment of the present application, based on the problem of how to regulate the line flow in the power system so that the system can adapt to the changes in reactive power demand caused by the access of new energy to the power grid, a line flow regulation method for the power system is designed. The method predicts the reactive power demand target value for a preset time period in the future by real-time acquisition of the power system operation data after the access of new energy. When the reactive power demand target value is within the regulation capacity range, multiple target devices (bypass switch, LC filter, H-bridge converter, DC capacitor) are screened based on capacity margin and electrical distance. In the system-level control process, a quadratic programming model is constructed to solve the output strategy of the target device, and in the device-level control process, the line flow is regulated by decoupling control technology. The actual power data after regulation is obtained, and the deviation from the target value is calculated. If the deviation exceeds the threshold, the target value is incrementally corrected and the output strategy is iteratively generated until the deviation meets the requirements. This achieves precise regulation of the line flow in the power system and solves the problems of voltage instability caused by the intermittent and fluctuating nature of renewable energy power generation in the reactive power flow control of the power grid.

[0069] It should be noted that although the steps in the above flowchart are shown in sequence as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders.

[0070] In another embodiment, Figure 7 As shown, the second aspect of the present invention provides a line flow control system for a power system, comprising: The target prediction module 10 is used to collect the operating data of the power system after the new energy equipment is connected in real time, and predict the reactive power demand target value of the power system in a preset time period in the future based on the operating data; an equipment selection module 20 for determining a plurality of target devices based on a capacity margin of the reactive power flow control device and an electrical distance between the reactive power flow control device and the new energy device when the reactive power demand target value is within a regulation capacity constraint range of the reactive power flow control device; the reactive power flow control device includes a bypass switch, an LC filter, an H-bridge converter, and a DC capacitor; The power flow control module 30 is used to construct and solve a quadratic programming model based on the reactive power demand target value, obtain the target device output strategy and send it to the corresponding target device, so as to control each target device to control the line power flow through the decoupling control technology; a deviation calculation module 40 for obtaining actual power data of the power system after power flow control of each target device line, and calculating a deviation between the actual power data and the reactive power demand target value; The iterative control module 50 is used to incrementally correct the reactive power demand target value when the deviation exceeds the preset deviation threshold, and iteratively execute the target equipment output strategy generation process according to the corrected reactive power demand target value until the actual power data finally obtained does not exceed the preset deviation threshold, so as to realize the control of the line flow in the power system.

[0071] It should be noted that the various modules in the above-mentioned line flow control system for an electric power system can be implemented in whole or in part through software, hardware, and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above-mentioned modules. For the specific definition of a line flow control system for an electric power system, please refer to the definition of a line flow control method for an electric power system above. The two have the same functions and effects and will not be repeated here.

[0072] A third aspect of the present invention provides an electronic device, comprising: processor, memory, and bus; The bus is used to connect the processor and the memory; The memory is used to store operation instructions; The processor is used to call the operation instruction, and the executable instruction enables the processor to perform operations corresponding to the line flow control method for the power system as shown in the first aspect of the present application.

[0073] In an alternative embodiment, an electronic device is provided, such as Figure 8 As shown, Figure 8 The electronic device 5000 shown includes: a processor 5001 and a memory 5003. The processor 5001 and the memory 5003 are connected, for example, via a bus 5002. Optionally, the electronic device 5000 may further include a transceiver 5004. It should be noted that in actual applications, the number of transceivers 5004 is not limited to one, and the structure of the electronic device 5000 does not constitute a limitation on the embodiments of the present application.

[0074] Processor 5001 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 the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. Processor 5001 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, and the like.

[0075] The bus 5002 may include a path for transmitting information between the above components. The bus 5002 may be a PCI bus or an EISA bus, etc. The bus 5002 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 8 Only one thick line is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0076] The memory 5003 may 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, a CD-ROM or other optical disk storage, an optical disc storage (including a compact disc, a laser disc, an optical disc, a digital versatile disc, a Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited to these.

[0077] The memory 5003 is used to store application code for executing the solution of the present application, and the execution is controlled by the processor 5001. The processor 5001 is used to execute the application code stored in the memory 5003 to implement the content shown in any of the above method embodiments.

[0078] Among them, electronic devices include but are not limited to: mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc.

[0079] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the method for controlling line flow in a power system as shown in the first aspect of the present application is implemented.

[0080] Another embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon. When the computer-readable storage medium is run on a computer, the computer can execute the corresponding contents of the aforementioned method embodiments.

[0081] In addition, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above method when executed by a processor.

[0082] In summary, the present invention relates to the technical field of power systems, and discloses a line flow control method, system, equipment and medium for power systems. The method predicts the reactive power demand target value of the system by collecting the operating data of the power system after connecting to new energy equipment, and when the value is within the adjustment capacity range of the reactive power flow control equipment including bypass switches, LC filters, H-bridge converters and DC capacitors, multiple target devices are determined according to the capacity margin of the equipment and the electrical distance between the equipment and the new energy equipment; a quadratic programming model is constructed and solved based on the reactive power demand target value, and the target device output strategy is obtained and sent to the corresponding target device to control each target device to control the line flow through decoupling control technology; the control result is verified. If the verification fails, the reactive power demand target value is incrementally corrected, and the strategy is re-solved until the final verification passes, so as to achieve effective control of the line flow in the power system.

[0083] Each embodiment in this specification is described in a progressive manner, and the same or similar parts of each embodiment can be directly referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. It should be noted that the various technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0084] The above-described embodiments merely represent several preferred implementations of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art could make several improvements and substitutions without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be based on the scope of protection of the claims.

Claims

1. A line flow control method for a power system, characterized in that: include: Real-time collection of operating data of the power system after the connection of new energy equipment, and prediction of the reactive power demand target value of the power system in a future preset time period based on the operating data; When the reactive power demand target value is within the regulation capacity constraint range of the reactive power flow control device, multiple target devices are determined based on the capacity margin of the reactive power flow control device and the electrical distance between the reactive power flow control device and the new energy device; the reactive power flow control device includes a bypass switch, an LC filter, an H-bridge converter, and a DC capacitor; A quadratic programming model is constructed and solved according to the reactive power demand target value to obtain a target device output strategy and send it to the corresponding target device, so as to control each target device to regulate the line power flow through a decoupling control technology; Acquiring actual power data of the power system after power flow control of each target device line, and calculating the deviation between the actual power data and the reactive power demand target value; When the deviation exceeds the preset deviation threshold, the reactive power demand target value is incrementally corrected, and the target device output strategy generation process is iteratively executed according to the corrected reactive power demand target value until the actual power data finally obtained does not exceed the preset deviation threshold, so as to realize the regulation of the line flow in the power system.

2. A line power flow control method for a power system according to claim 1, characterized in that: The real-time collection of operating data of the power system after the new energy equipment is connected, and prediction of a reactive power demand target value of the power system within a future preset time period based on the operating data, includes: collecting in real time the output power, line flow data, and equipment operating status data of the power system after the new energy equipment is connected, as the operating data; The operating data is processed based on a sliding time window or a pre-trained long short-term memory network to predict the reactive power demand change trend of the power system in a future preset time period and obtain a reactive power demand target value.

3. The line flow control method for a power system according to claim 1, characterized in that: The determining of the plurality of target devices according to the capacity margin of the reactive power flow control device and the electrical distance between the reactive power flow control device and the new energy device includes: Obtaining the capacity margin of the reactive power flow control device, and determining the electrical distance between the reactive power flow control device and the new energy device according to the impedance modulus or electrical coupling of the reactive power flow control device; Normalizing the capacity margin and the electrical distance, and performing weighted summation on the normalized results to obtain a priority weight of the reactive power flow control device; Based on the priority weights, the reactive power flow control devices are sorted from high to low to construct a regulation queue; According to the reactive power demand target value, a number of target devices are selected from the adjustment queue in a weighted ratio.

4. A line power flow control method for a power system according to claim 1, characterized in that: The method of constructing and solving a quadratic programming model based on the reactive power demand target value to obtain a target device output strategy includes: Obtaining loss data, output voltage, and usage capacity of each target device to construct an operation function of each target device using a Lagrangian method; Collecting the real-time power flow value of the controlled line of each target device, and using the sum of squares of errors between the real-time power flow value and a given reference value as the optimization function of each target device; Constructing a device quantity variable function according to the number of the target devices, and constructing a planning sub-model for each of the target devices based on the reactive power demand target value through each of the operation functions, each of the optimization functions, and the device quantity variable function; The planning sub-models are integrated to generate a quadratic programming model, and the quadratic programming model is solved by calling the interior point solver under preset constraints to obtain the output voltage amplitude and phase distribution of each target device as the output strategy output of the target device.

5. A line flow control method for a power system according to claim 4, characterized in that: The preset constraints include single device output constraints, transformer voltage constraints and transformer capacity constraints; wherein, The method of solving the quadratic programming model by calling an interior point solver under preset constraints to obtain the output voltage amplitude and phase distribution of each target device as the output strategy output of the target device includes: Under the preset constraints, the quadratic programming model is solved once by calling an interior point solver to obtain the initial output voltage amplitude and phase distribution of each target device; If the initial output voltage amplitude and phase distribution do not satisfy the single device output constraint or the transformer capacity constraint, adjusting the transformer voltage constraint to form a transformer voltage soft constraint; Using the square of the transformer voltage soft constraint as a penalty term, and updating the quadratic programming model based on the penalty term to obtain a quadratic programming target model; Under the single device output constraint, the transformer capacity constraint and the transformer voltage soft constraint, the quadratic programming target model is solved quadratically by calling the interior point solver to obtain the output voltage amplitude and phase distribution of each target device as the output strategy output of the target device.

6. A line power flow control method for a power system according to claim 1, characterized in that: The controlling of each target device to regulate the line flow through the decoupling control technology includes: Constructing a loop model of each target device in the abc three-phase stationary coordinate system, and performing a single-phase Park transform on each loop model to obtain a voltage model and a current model of each target device in a two-phase synchronous rotating coordinate system; Introducing intermediate variables into each of the voltage models to perform cross-decoupling to obtain a decoupling model of each of the target devices, and processing each of the decoupling models through a PI controller to obtain a reference voltage value of each of the target devices; Processing each of the current models using Park transformation and feedforward decoupling method to obtain a current processing model of each of the target devices, and processing each of the current processing models using a PI controller to obtain a reference current value of each of the target devices; Based on each of the reference voltage values ​​and each of the reference current values, a modulation signal for the H-bridge converter in each of the target devices is generated, and each of the bypass switches is controlled according to each of the modulation signals to obtain an equivalent voltage phasor to control each of the target devices to regulate the line flow.

7. A line power flow control method for a power system according to claim 1, characterized in that: The method further comprises: Determining a DC voltage according to the working requirements of the reactive power flow control device and the voltage of the access point of the new energy device, and determining a ripple current based on the circuit topology of the reactive power flow control device; determining a capacitance value of the DC capacitor based on the DC voltage and the ripple current; The normalized LPF is subjected to cutoff frequency conversion and characteristic impedance conversion processing to determine the parameters of the LC filter; wherein the normalized LPF is configured to have an impedance of 1 And the cutoff frequency is Hz LPF.

8. A line flow control system for a power system, characterized in that: include: A target prediction module is used to collect real-time operating data of the power system after the new energy equipment is connected, and to predict the reactive power demand target value of the power system in a preset time period in the future based on the operating data; an equipment selection module, configured to determine a plurality of target equipment based on the capacity margin of the reactive power flow control equipment and the electrical distance between the reactive power flow control equipment and the new energy equipment when the reactive power demand target value is within the regulation capacity constraint range of the reactive power flow control equipment; The reactive power flow control equipment includes a bypass switch, an LC filter, an H-bridge converter and a DC capacitor; A power flow control module is used to construct and solve a quadratic programming model based on the reactive power demand target value, obtain a target device output strategy, and send it to the corresponding target device to control each target device to control the line power flow through decoupling control technology; a deviation calculation module, configured to obtain actual power data of the power system after power flow control of each target device line, and calculate a deviation between the actual power data and the reactive power demand target value; An iterative control module is used to incrementally correct the reactive power demand target value when the deviation exceeds a preset deviation threshold, and iteratively execute the target equipment output strategy generation process according to the corrected reactive power demand target value until the actual power data finally obtained does not exceed the preset deviation threshold, so as to realize the control of the line flow in the power system.

9. An electronic device, characterized in that: The method comprises a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, the method for line flow control in a power system as claimed in any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium includes a stored computer program, wherein when the device where the computer-readable storage medium is located executes the computer program, the line flow control method for the power system according to any one of claims 1 to 7 is implemented.

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