Power transmission line dynamic load management method based on load feedback adjustment

Abstract

The invention relates to the technical field of power transmission control, in particular to a power transmission line dynamic load management method based on load feedback regulation, which comprises the following steps: estimating a first temperature rise wire temperature after a preset time period for a to-be-evaluated line, and calculating a first dynamic long-term current-carrying capacity; determining a current-carrying capacity value range according to the first dynamic long-term current-carrying capacity, and estimating the temperature of the second temperature rise lead; and calculating a second dynamic long-term current-carrying capacity at the second temperature rise wire temperature, and then screening to obtain an actual dynamic long-term current-carrying capacity. Aiming at the problem that the existing dynamic rated value technology is insufficient in response to load change, the available current-carrying capacity range of the line is determined by estimating the temperature rise and the current-carrying capacity of each line to be evaluated in advance after a preset time period, feasible current-carrying capacity parameters are searched in the range, and the corresponding temperature rise condition is estimated; therefore, errors of the temperature rise and the current-carrying capacity which are obtained through final estimation are small, and accurate control over the line is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of power transmission control, and in particular to a method for dynamic load management of a power transmission line based on load feedback regulation. Background Art

[0002] Transmission control refers to the process of allocating various parameters according to line conditions in a high-voltage transmission system. Since the capacity of a transmission line is affected by various environmental parameters, for example, when the ambient temperature is high, the temperature range within which the line is allowed to operate becomes narrower, and the available line capacity will decrease. Incorrectly estimating the line capacity will lead to a significant reduction in economic benefits. Therefore, it is necessary to accurately estimate and timely control various parameters during the transmission process. The stable operation of the existing power system depends on the precise control of the transmission line capacity by the power system dispatcher. However, the traditional power system operation mode usually adopts the thermal rating of the transmission line based on static environmental conditions, which does not fully utilize the capacity margin in the actual operating environment. With the digital development of the power system, how to more efficiently utilize the existing transmission network resources has become an urgent need. In recent years, the dynamic rating (DLR) technology has gradually attracted widespread attention because it can be adjusted according to real-time environmental conditions to ensure that the transmission line operates close to its maximum limit. In particular, by combining regional meteorological conditions, the dynamic rating technology has obvious advantages in improving the operating efficiency of transmission lines and ensuring safe and stable operation.

[0003] Although dynamic rating technology has certain flexibility compared to traditional static rating, the current technology still has many shortcomings. Existing dynamic capacity increase monitoring systems mostly dynamically adjust the current carrying capacity of overhead lines based on real-time data. However, these systems only provide capacity information at the current moment and cannot provide effective decision support for power system dispatchers under future load changes.

[0004] First, the traditional method of calculating the dynamic current carrying capacity of transmission lines relies on real-time regional meteorological conditions, while the operation planning of the power market usually needs to be carried out several hours or even a day in advance. This will lead to a lag in decision-making information, making it difficult for dispatchers to accurately predict future changes in line capacity, increasing the risk of system operation. Secondly, short-term meteorological forecasting models also have limitations in practical applications. Current short-term forecasts rely only on meteorological models, which themselves have prediction errors and are difficult to provide accurate meteorological data, making it difficult for dispatchers to trust the predicted current carrying capacity in practical applications. Finally, existing dynamic rating technologies fail to effectively respond to sudden load changes. Because the impact of load changes on line temperature and future dynamic current carrying capacity is not fully considered, the current dynamic rating technology cannot be adjusted accurately in time when the load fluctuates drastically, posing a safety hazard. Summary of the invention

[0005] In view of the above problems existing in the prior art, a method for dynamic load management of a transmission line based on load feedback regulation is now provided.

[0006] The specific technical scheme is as follows: A method for dynamic load management of a transmission line based on load feedback regulation, characterized in that it includes: step S1: constructing a state vector for the line to be evaluated and estimating the first temperature-rise conductor temperature after a predetermined time period; step S2: estimating a first dynamic long-term current carrying capacity according to the first temperature-rise conductor temperature; step S3: determining a current carrying capacity value range of a second dynamic long-term current carrying capacity according to the first dynamic long-term current carrying capacity for the line to be evaluated, and estimating a second temperature-rise conductor temperature after the line to be evaluated has been running for a predetermined time according to the current carrying capacity value range; step S4: calculating a second dynamic long-term current carrying capacity at the second temperature-rise conductor temperature according to the second temperature-rise conductor temperature; step S5: judging whether the error between the second dynamic long-term current carrying capacity and the current carrying capacity to be predicted in the current carrying capacity value range is within the error setting range; if so, outputting the second dynamic long-term current carrying capacity as the actual dynamic current carrying capacity; if not, increasing the predetermined time according to a preset step length, and then returning to step S3; on the other hand, in step S1, the method for generating the first temperature-rise conductor temperature includes: ; In the formula, is the first temperature-rise conductor temperature; for t = Wire temperature at time 0; For the current running Initial temperature rise under is the heat generated by the AC resistance per unit length of the wire under initial conditions; is the solar heat absorption per unit length of the conductor under initial conditions; is the convective heat dissipation per unit length of the wire under initial conditions; is the radiation heat dissipation per unit length of the wire under initial conditions; dt is the time increment, dt =Δ t .

[0007] On the other hand, the step S1 includes: step S11: collecting thermal parameter information of the circuit to be evaluated; step S12: generating an initial temperature rise according to the thermal parameter information; step S13: generating the first temperature rise conductor temperature according to the initial temperature rise.

[0008] On the other hand, in step S2, the method for generating the first dynamic long-term current carrying capacity includes:

[0009] In the formula, is the first dynamic long-term current carrying capacity; Indicates the current running on the wire With wire temperature The radiation heat dissipation per unit length of the conductor; Indicates the current running on the wire With wire temperature Convection heat dissipation per unit length of the conductor; Indicates the current running on the wire With wire temperature The solar heat absorption per unit length of the conductor; is the conductor temperature limit.

[0010] On the other hand, the step S3 includes: step S31: generating the current carrying capacity value range according to the first dynamic long-term current carrying capacity; step S32: searching in the current carrying capacity value range according to a preset step size to obtain multiple feasible current carrying capacities to be predicted; step S33: generating the second temperature rise conductor temperature according to the current carrying capacities to be predicted.

[0011] On the other hand, in step S33, the method for generating the second temperature-rise conductor temperature includes: ; In the formula, is the second temperature rise conductor temperature; is the conductor temperature before temperature rise; is the current ambient temperature rise; Indicates the current running on the wire I K With wire temperature The heat generated by the AC resistance per unit length of the wire; Indicates the current running on the wire I K With wire temperature The solar heat absorption per unit length of the conductor; Indicates the current running on the wire IK With wire temperature Convection heat dissipation per unit length of the conductor; Indicates the current running on the wire I K With wire temperature The radiation heat dissipation per unit length of the wire.

[0012] On the other hand, in step S4, the method for generating the second dynamic long-term current carrying capacity includes: ; In the formula, is the second dynamic long-term current carrying capacity; Indicates the current running on the wire I K With wire temperature T lim Radiative heat dissipation per unit length of the conductor; Indicates the current running on the wire I K With wire temperature T lim Convection heat dissipation per unit length of the conductor; Indicates the current running on the wire I K With wire temperature T lim The solar heat absorption per unit length of the conductor.

[0013] A memory includes computer instructions. When a computer device executes the computer instructions, the above-mentioned transmission line dynamic load management method is executed.

[0014] The above technical scheme has the following advantages or beneficial effects: in view of the problems of prediction hysteresis, insufficient accuracy of short-term meteorological forecast models, poor local applicability and insufficient response to load changes in existing dynamic rating technologies, this scheme introduces an adjustment process based on real-time load feedback. By pre-estimating the temperature rise and current carrying capacity after a predetermined time period for each line to be evaluated, the available current carrying capacity range of the line is determined, and then feasible current carrying capacity parameters are searched within the range and the corresponding temperature rise conditions are estimated, so that the errors of the final estimated temperature rise and current carrying capacity are small, avoiding the problem of poor accuracy of using the current temperature for estimation in existing estimation schemes, and realizing accurate control of the line. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The embodiments of the present invention will be described more fully with reference to the attached drawings, which are provided for illustration and description only and are not intended to limit the scope of the present invention.

[0016] Figure 1 It is an overall schematic diagram of an embodiment of the present invention; Figure 2 This is a schematic diagram of step S1 in an embodiment of the present invention; Figure 3 This is a schematic diagram of step S3 in an embodiment of the present invention; Figure 4 Schematic diagram of the dynamic current carrying capacity adjustment effect in an embodiment of the present invention. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0019] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0020] The present invention comprises: a method for dynamic load management of a transmission line based on load feedback regulation, such as Figure 1 As shown, it includes: step S1: constructing a state vector for the line to be evaluated and estimating the first temperature-rise conductor temperature after a predetermined time period; step S2: estimating a first dynamic long-term current carrying capacity according to the first temperature-rise conductor temperature; step S3: determining a current carrying capacity value range of a second dynamic long-term current carrying capacity according to the first dynamic long-term current carrying capacity for the line to be evaluated, and estimating a second temperature-rise conductor temperature at the second temperature-rise conductor temperature after the line to be evaluated has been running for a predetermined time according to the current carrying capacity value range; step S4: calculating a second dynamic long-term current carrying capacity at a second temperature-rise conductor temperature according to the second temperature-rise conductor temperature; step S5: judging whether an error between the second dynamic long-term current carrying capacity and a current carrying capacity to be predicted in the current carrying capacity value range is within an error setting range; if so, outputting the second dynamic long-term current carrying capacity as the actual dynamic current carrying capacity; if not, increasing a predetermined time according to a preset step length, and then returning to step S3.

[0021] Specifically, in response to the problems of prediction hysteresis, insufficient accuracy of short-term meteorological forecast models, poor local applicability and insufficient response to load changes in existing dynamic rating technologies, this solution introduces a regulation process based on real-time load feedback. In particular, in the calculation process, after estimating the current carrying capacity value range, the second temperature rise conductor temperature that may be reached by the line to be evaluated after running for a predetermined time under the current carrying capacity value range is first estimated. Based on the estimated second temperature rise conductor temperature, the line capacity at this temperature is evaluated to obtain the second dynamic long-term current carrying capacity, thereby avoiding the inaccuracy caused by the evaluation scheme in the prior art that evaluates according to the temperature in the initial state. Furthermore, in order to ensure the accuracy of the estimation, multiple current carrying capacities to be predicted are determined in the predetermined current carrying capacity value range, and the accuracy of the prediction process is determined according to the error between the second dynamic long-term current carrying capacity and the current carrying capacity to be predicted. If it is inaccurate, it may be that the line has not yet entered a steady state, so the prediction time period is extended to improve the accuracy of the measurement.

[0022] Specifically, for each line to be evaluated, a state vector is constructed at the initial stage of the evaluation. As the initial value of the system, the state vector corresponds to the various states of the line to be evaluated, such as, for t = Ambient temperature at time 0, in °C; for t = Wire temperature at time 0, unit: °C; for t =Sunlight intensity at time 0, unit: W / m 2 ; for t =The conductor current at time 0, in A; for t =The wind speed at time 0, in m / s.

[0023] Based on the above state vector, the temperature rise of the conductor of the line to be evaluated and the first temperature rise of the conductor after a period of time can be calculated under this state.

[0024] With respect to the first temperature rise of the conductor, the line capacity may be evaluated to determine the first dynamic long-term current carrying capacity of the line that can enter steady-state operation under current conditions.

[0025] Then, the static rated current carrying capacity of the conductor and the first dynamic long-term current carrying capacity are used as the upper and lower boundaries of the search range, and a search is performed according to a preset step length to obtain a plurality of current carrying capacities to be predicted.

[0026] For multiple current carrying capacities to be predicted, the temperature change under the corresponding current carrying capacity can be simulated based on the above state vector as the second temperature-rise conductor temperature; based on the second temperature-rise conductor temperature, the second dynamic long-term current carrying capacity that can be operated for a long time when the conductor enters a steady state at this temperature is calculated.

[0027] Generally speaking, the second dynamic long-term current carrying capacity and the current carrying capacity to be predicted should have a small error, and the current carrying capacity to be predicted whose error range meets the requirements is selected for output as the actual dynamic long-term current carrying capacity in the actual control process.

[0028] In one embodiment, in step S1, the method for generating the first temperature-rise conductor temperature includes: ; In the formula, is the first temperature rise conductor temperature; for t = Wire temperature at time 0; For the current running Initial temperature rise under is the heat generated by the AC resistance per unit length of the wire under initial conditions; is the solar heat absorption per unit length of the conductor under initial conditions; is the convective heat dissipation per unit length of the wire under initial conditions; is the radiation heat dissipation per unit length of the wire under initial conditions; dt is the time increment, dt =Δ t .

[0029] Specifically, in order to effectively estimate the temperature rise of the conductor under the initial conditions, in this embodiment, the initial temperature rise is first calculated by combining various environmental parameters. Then, the first temperature rise conductor temperature is calculated in combination with the initial temperature.

[0030] Among them, the initial temperature rise The calculation process is mainly related to four environmental parameters, including line resistance heat generation, sunlight west heat generation, convection heat generation and radiation heat generation.

[0031] Specifically: (1) , , R 20 It is the DC resistance value of the conductor when the temperature is 20℃, in Ω / m; α20 The temperature coefficient of the conductor material at 20°C, in units of 1 / °C; k 1 is the skin effect coefficient, the conductor cross-sectional area is less than or equal to 400mm 2 When the recommended value is 0.0025, it is greater than 400mm 2 It is recommended to take 0.01; k 2 is the combined influence coefficient of proximity effect and hysteresis loss.

[0032] (2) , ε It is the heat absorption coefficient of the wire surface. The bright new wire is 0.35~0.46, and the old wire or the wire with black preservative is 0.90~0.95.

[0033] (3) , μ 0 The conductor temperature is The kinematic viscosity of the air layer on the conductor surface is m 2 / s; λ 0 The conductor temperature is The heat transfer coefficient of the air layer on the conductor surface is W / m·℃; D is the conductor diameter, in m.

[0034]

[0035]

[0036] (4) , π is the ratio of pi; s is the Stefan-Boltzmann constant, 5.67×10 -8 W·m -2 ·K -4 , σ The surface radiation coefficient of the wire is 0.23~0.43 for bright new wire and 0.90~0.95 for old wire or wire with black preservative.

[0037] (5) Taking steel core aluminum stranded wire as an example, , m , m stl , m al are the mass per unit length of steel and aluminum, steel, and aluminum, respectively, in kg / m; c p , c stl , c alThe specific heat capacity of steel and aluminum, steel and aluminum respectively, in J / (kg·℃); T line is the conductor temperature, unit: °C; t is the time, unit is s.

[0038] Based on the above process, if Figure 2 As shown, step S1 includes: step S11: collecting thermal parameter information of the circuit to be evaluated; step S12: generating an initial temperature rise according to the thermal parameter information; step S13: generating a first temperature rise conductor temperature according to the initial temperature rise.

[0039] In one embodiment, in step S2, the method for generating the first dynamic long-term current carrying capacity includes:

[0040] In the formula is the first dynamic long-term current carrying capacity; Indicates the current running on the wire With wire temperature Radiative heat dissipation per unit length of the conductor; Indicates the current running on the wire With wire temperature Convection heat dissipation per unit length of the conductor; Indicates the current running on the wire With wire temperature The solar heat absorption per unit length of the conductor; is the conductor temperature limit.

[0041] Specifically, after the first temperature-rise conductor temperature is calculated, the first dynamic long-term current-carrying capacity that can be operated for a long time at the corresponding temperature can be calculated based on the above process.

[0042] in, Indicates the current running on the wire With wire temperature The radiation heat dissipation per unit length of the conductor, unit J; Indicates the current running on the wire With wire temperature T lim Convection heat dissipation per unit length of the conductor, unit J; Indicates the current running on the wire With wire temperature T lim The solar heat absorption per unit length of the conductor at that time, unit is J.

[0043] (1)

[0044] (2) , μ m The conductor temperature is T lim The kinematic viscosity of the air layer on the conductor surface is m 2 / s; λ m The conductor temperature is T lim The heat transfer coefficient of the air layer on the surface of the conductor at this time, the unit is W / m·℃.

[0045]

[0046]

[0047] (3)

[0048] (4) , T lim is the conductor temperature limit, unit is ℃.

[0049] In one embodiment, Figure 3 As shown, step S3 includes: step S31: generating a current carrying capacity value range according to the first dynamic long-term current carrying capacity; step S32: searching in the current carrying capacity value range according to a preset step size to obtain multiple feasible current carrying capacities to be predicted; step S33: generating a second temperature rise conductor temperature according to the current carrying capacities to be predicted.

[0050] Specifically, after determining the first dynamic long-term current carrying capacity, the static rated current carrying capacity of the conductor and the first dynamic long-term current carrying capacity can be used as the upper and lower boundaries of the search range, and the search can be performed according to a preset step size to obtain multiple current carrying capacities to be predicted.

[0051] For multiple current carrying capacities to be predicted, the temperature change conditions under the corresponding current carrying capacities can be simulated based on the state vectors respectively as the second temperature-rise conductor temperature.

[0052] In one embodiment, in step S33, the method for generating the second temperature-rise conductor temperature includes: ; In the formula, is the second temperature rise conductor temperature; Temperature of the conductor before temperature rise; is the current ambient temperature rise; Indicates the current running on the wire I K With wire temperature The heat generated by the AC resistance per unit length of the wire; Indicates the current running on the wire I K With wire temperature The solar heat absorption per unit length of the conductor; Indicates the current running on the wire I K With wire temperature Convection heat dissipation per unit length of the conductor; Indicates the current running on the wire I K With wire temperature The radiation heat dissipation per unit length of the wire.

[0053] Among them, the definition is t K The dynamic current carrying capacity that can still operate for a long time in an environment with a constant temperature rise is I K , value range I K ∈[ I R , I M ], unit A; Δ I =1; I R is the static rated current carrying capacity of the conductor, in A. And set the step size Δ I . Traverse I K Substitute the current operating current into the temperature rise model to calculate the temperature rise under the current environment and i Wire temperature at time +1 : The calculation methods of the above-mentioned environmental heat include: (1) ,

[0054] (2)

[0055] (3) , μ i The conductor temperature is The kinematic viscosity of the air layer on the conductor surface is m 2 / s; λi The conductor temperature is The heat transfer coefficient of the air layer on the surface of the conductor at this time, the unit is W / m·℃.

[0056]

[0057]

[0058] (4)

[0059] Preferably, t K The value range of should at least reserve enough time for the dispatcher to plan the line operation in advance, and should not exceed the time it takes for the conductor to reach a steady state; I K The range of values ​​is usually a reasonable range of dynamic long-term current carrying capacity to ensure that possible current carrying capacity values ​​are fully covered; the step size Δ I It is advisable to take a fixed value within the range of 1 to 10 to ensure that there are sufficiently dense values ​​within the current range.

[0060] Typical, t K The value range of t K ∈[30, 240].

[0061] In one embodiment, in step S4, the method for generating the second dynamic long-term current carrying capacity includes: ; In the formula, is the second dynamic long-term current carrying capacity; Indicates the current running on the wire I K With wire temperature T lim Radiative heat dissipation per unit length of the conductor; Indicates the current running on the wire I K With wire temperature T lim Convection heat dissipation per unit length of the conductor; Indicates the current running on the wire I K With wire temperature T lim The solar heat absorption per unit length of the conductor.

[0062] Among them, (1)

[0063] (2)

[0064] (3)

[0065] Indicates the current running on the wire I K With wire temperature T lim The radiation heat dissipation per unit length of the conductor; Indicates the current running on the wire With wire temperature T lim The radiation heat dissipation per unit length of the conductor, unit J; ; μ m The conductor temperature is T lim The kinematic viscosity of the air layer on the conductor surface is m 2 / s; λ m The conductor temperature is T lim The heat transfer coefficient of the air layer on the surface of the conductor at this time, the unit is W / m·℃.

[0066]

[0067]

[0068] ε It is the heat absorption coefficient of the wire surface. The bright new wire is 0.35~0.46, and the old wire or the wire with black preservative is 0.90~0.95.

[0069] for t =Sunlight intensity at time 0.

[0070] In one embodiment, in step S5, the actual dynamic long-term current carrying capacity is determined according to the error between the second dynamic long-term current carrying capacity and the current carrying capacity to be predicted.

[0071] Specifically, in order to achieve a better estimation effect, in this embodiment, for each generated second dynamic long-term current carrying capacity, the error between the current carrying capacity to be predicted is calculated, that is, ,in is the second dynamic long-term current carrying capacity, It is the second dynamic long-term current carrying capacity.

[0072] when When it is, it is the final calculated dynamic long-term current carrying capacity, otherwise, another second dynamic long-term current carrying capacity is calculated.

[0073] Generally speaking δ The value of should minimize the calculated error as much as possible, but should not be too small to increase unnecessary calculations. It should be a natural number between 0 and 10 and can be adjusted appropriately according to the rated current carrying capacity of the conductor. δ The value of, for example, δ =1.

[0074] The control results achieved based on the above intelligent adjustment method are as follows Figure 4 As shown, the ordinate corresponds to the dynamic current carrying capacity comparison, and the abscissa is the date. It can be seen that the adjustment process based on this solution is smoother and more practical.

[0075] A memory includes computer instructions. When a computer device executes the computer instructions, the above-mentioned transmission line dynamic load management method is executed.

[0076] Those skilled in the art will appreciate that various aspects of the present invention, or possible implementations of various aspects, may be specifically implemented as systems, methods, or computer program products. Therefore, various aspects of the present invention, or possible implementations of various aspects, may take the form of complete hardware embodiments, complete software embodiments (including firmware, resident software, etc.), or embodiments of combined software and hardware aspects, all collectively referred to herein as "circuits," "modules," or "systems." In addition, various aspects of the present invention, or possible implementations of various aspects, may take the form of computer program products, which refer to computer instructions stored in a memory.

[0077] The memory may be a computer-readable signal medium or a computer-readable storage medium. Computer-readable storage media include but are not limited to electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices or apparatuses, or any suitable combination of the foregoing, such as random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable read-only memory (CD-ROM).

[0078] The processor in the computer reads the computer instructions stored in the memory, so that the processor can execute the functional actions specified in each step or the combination of steps in the flowchart; and generate a device for implementing the functional actions specified in each block or the combination of blocks in the block diagram.

[0079] It should be understood that the processor in the computer can be understood as one or more application-specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field programmable gate arrays (FPGAs), general-purpose processors, controllers, microcontrollers (MCUs), microprocessors, or other electronic components implemented to execute the aforementioned computer instructions.

[0080] Computer instructions can be executed completely on the user's local computer, partially on the user's local computer, as a separate software package, partially on the user's local computer and partially on a remote computer, or completely on a remote computer or server. It should also be noted that in some alternative embodiments, the functions noted in each step in the flow chart or each block in the block diagram may not occur in the order noted in the figure. For example, depending on the functions involved, two steps or two blocks shown in succession may actually be executed roughly simultaneously, or these blocks may sometimes be executed in reverse order.

[0081] Of course, in actual application, the various components in the computer system are coupled together through the bus system. It can be understood that the bus system is used to realize the connection and communication between these components. In addition to the data bus, the bus system also includes a power bus, a control bus and a status signal bus.

[0082] The above are only preferred embodiments of the present invention, and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for dynamic load management of a transmission line based on load feedback regulation, characterized in that: include: Step S1: constructing a state vector for the line to be evaluated and estimating the first temperature rise conductor temperature after a predetermined time period; Step S2: obtain a first dynamic long-term current-carrying capacity according to the first temperature-rise conductor temperature estimation; Step S3: determine the current-carrying capacity value range of the second dynamic long-term current-carrying capacity for the line to be evaluated according to the first dynamic long-term current-carrying capacity, and estimate the second temperature-rise conductor temperature of the line to be evaluated after the line to be evaluated has been running for a predetermined time according to the current-carrying capacity value range; Step S4: calculate the second dynamic long-term current-carrying capacity at the second temperature-rise conductor temperature according to the second temperature-rise conductor temperature; Step S5: determine whether the error between the second dynamic long-term current-carrying capacity and the current-carrying capacity to be predicted in the current-carrying capacity value range is within the error setting range; if so, output the second dynamic long-term current-carrying capacity as the actual dynamic current-carrying capacity; if not, increase the predetermined time according to a preset step size, and then return to the step S3.

2. The method for dynamic load management of a power transmission line according to claim 1, characterized in that: In the step S1, the method for generating the first temperature-rise conductor temperature includes: ； In the formula, is the first temperature-rise conductor temperature; for t = Wire temperature at time 0; For the current running Initial temperature rise under is the heat generated by the AC resistance per unit length of the wire under initial conditions; is the solar heat absorption per unit length of the conductor under initial conditions; is the convective heat dissipation per unit length of the wire under initial conditions; is the radiation heat dissipation per unit length of the wire under initial conditions; It is the product of the equivalent mass and specific heat capacity per unit length of the conductor; dt is the time increment, dt =Δ t .

3. The method for dynamic load management of a power transmission line according to claim 2, characterized in that: The step S1 comprises: step S11: collecting thermal parameter information of the circuit to be evaluated; step S12: generating an initial temperature rise according to the thermal parameter information; and step S13: generating the first temperature rise conductor temperature according to the initial temperature rise.

4. The method for dynamic load management of a power transmission line according to claim 1, characterized in that: In step S2, the method for generating the first dynamic long-term current carrying capacity includes: ； In the formula, is the first dynamic long-term current carrying capacity; Indicates the current running on the wire With wire temperature Radiative heat dissipation per unit length of the conductor; Indicates the current running on the wire With wire temperature Convection heat dissipation per unit length of the conductor; Indicates the current running on the wire With wire temperature The solar heat absorption per unit length of the conductor; is the conductor temperature limit.

5. The method for dynamic load management of a power transmission line according to claim 1, characterized in that: The step S3 comprises: step S31: generating the current carrying capacity value range according to the first dynamic long-term current carrying capacity; step S32: searching in the current carrying capacity value range according to a preset step size to obtain a plurality of feasible current carrying capacities to be predicted; step S33: generating the second temperature rise conductor temperature respectively according to the current carrying capacities to be predicted.

6. The method for dynamic load management of a power transmission line according to claim 5, characterized in that: In the step S33, the method for generating the second temperature-rise conductor temperature includes: ； In the formula, is the second temperature rise conductor temperature; is the conductor temperature before temperature rise; is the current ambient temperature rise; Indicates the current running on the wire I K With wire temperature The heat generated by the AC resistance per unit length of the wire; Indicates the current running on the wire I K With wire temperature The solar heat absorption per unit length of the conductor; Indicates the current running on the wire I K With wire temperature Convection heat dissipation per unit length of the conductor; Indicates the current running on the wire I K With wire temperature Radiative heat dissipation per unit length of the conductor; It is the product of the equivalent mass per unit length of the wire and its specific heat capacity.

7. The method for dynamic load management of a power transmission line according to claim 1, characterized in that: In step S4, the method for generating the second dynamic long-term current carrying capacity includes: ； In the formula, is the second dynamic long-term current carrying capacity; Indicates the current running on the wire I K With wire temperature T lim Radiative heat dissipation per unit length of the conductor; Indicates the current running on the wire I K With wire temperature T lim Convection heat dissipation per unit length of the conductor; Indicates the current running on the wire I K With wire temperature T lim The solar heat absorption per unit length of the conductor.

8. A memory comprising computer instructions, characterized in that: When the computer device executes the computer instructions, the method for dynamic load management of a transmission line as described in any one of claims 1 to 7 is executed.

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