A method and system for calculating the thermal transient time constant of a bare conductor under standard conditions

Abstract

The present invention relates to a method and system for calculating the thermal transient time constant of a bare conductor under standard conditions. The method comprises the following steps: obtaining the specification parameters of the bare conductor; calculating the specific heat capacity per unit length of the bare conductor according to the specification parameters of the bare conductor: #imgabs0# wherein C is the specific heat capacity per unit length of the bare conductor, m AL is the weight of aluminum per unit length of bare conductor, m AL =ρ AL S AL L, ρ AL is the density of aluminum, S AL is the aluminum cross-sectional area of ​​the bare wire, L is the unit length of the bare wire, c AL is the specific heat capacity of aluminum, m T is the weight of steel per unit length of bare conductor, m T =ρ T S T L, ρ T is the density of steel, S T is the steel cross-sectional area of ​​the bare conductor, c T is the specific heat capacity of steel, W is the mass of bare wire per unit length; the thermal transient time constant is calculated based on the specific heat capacity of bare wire per unit length: #imgabs1##imgabs2#where, θ a is the air environment temperature of the thermal transient process, R is the DC resistance at 20℃, C is the specific heat capacity of the above-mentioned bare wire per unit length, and W is the mass of the above-mentioned bare wire per unit length.

Description

Technical Field

[0001] The invention relates to a method and a system for calculating a thermal transient time constant of a bare conductor under standard conditions, and belongs to the technical field of transmission line operation and control. Background Art

[0002] When the transmission line suddenly switches to the N-1 state in normal operation, the current carrying capacity of the line jumps from a lower state I1 to another higher state I2. Figure 1 In a certain period of time, the conductor temperature gradually rises to another higher state. This process is called the line thermal transient process. If this process is equivalent to the first-order step response of the LRC loop in circuit theory, the line temperature at each moment can be calculated using the following formula.

[0003] θ t =θ i +(θ s -θ i )(1-e -t / τ )

[0004] In the formula, θ t represents the line temperature at time t, θ i represents the initial line temperature, θ s Indicates the line temperature when the wire finally reaches the steady state, the temperature unit is Celsius / ℃; t is the time it takes for the state transition, the unit is second / s; τ is the time constant, the unit is second / s;

[0005] If we set the maximum temperature that the wire can reach, θ s and the overload time t, the dynamic change of the overhead conductor temperature during this period can be calculated using (Equation 1). i ,θ s , t are all known quantities, θ t is the variable to be determined, but there is no data available for the time constant τ, so numerical calculus needs to be used to iterate the calculation, and the calculation process is very complicated. Summary of the invention

[0006] In order to solve the problems existing in the above-mentioned prior art, the present invention proposes a method and system for calculating the thermal transient time constant of a bare conductor under standard conditions, and proposes a new calculation method, which saves complicated calculation steps. At the same time, the calculation results can meet the engineering design requirements and power grid operation and dispatching requirements, greatly improving the design efficiency.

[0007] The technical solution of the present invention is as follows:

[0008] In the first aspect, the present invention proposes a method for calculating the thermal transient time constant of a bare conductor under standard conditions, wherein the standard condition is that the solar radiation power is 1000W / m 2, the convection heat dissipation wind speed is 0.5m / s, the conductor radiation heat dissipation coefficient and the conductor surface heat absorption coefficient are both 0.9; the bare conductor is steel core aluminum stranded wire, and the calculation method includes the following steps:

[0009] Get the specification parameters of bare wire;

[0010] According to the specification parameters of the bare wire, calculate the specific heat capacity per unit length of the bare wire:

[0011]

[0012] Where C is the specific heat capacity per unit length of bare wire, m AL is the weight of aluminum per unit length of bare conductor, m AL =ρ AL S AL L, ρ AL is the density of aluminum, S AL is the aluminum cross-sectional area of ​​the bare wire, L is the unit length of the bare wire, c AL is the specific heat capacity of aluminum, m T is the weight of steel per unit length of bare conductor, m T =ρ T S T L, ρ T is the density of steel, S T is the steel cross-sectional area of ​​the bare conductor, c T is the specific heat capacity of steel, W is the mass of bare wire per unit length;

[0013] Calculate the thermal transient time constant based on the specific heat capacity per unit length of bare wire:

[0014]

[0015] In the formula, θ a is the air environment temperature of the thermal transient process, R is the DC resistance at 20℃, C is the specific heat capacity of the above-mentioned bare wire per unit length, and W is the mass of the above-mentioned bare wire per unit length.

[0016] In the second aspect, the present invention proposes a calculation system for the thermal transient time constant of a bare conductor under standard conditions, wherein the standard condition is a solar radiation power of 1000W / m 2 , the convection heat dissipation wind speed is 0.5m / s, the conductor radiation heat dissipation coefficient and the conductor surface heat absorption coefficient are both 0.9; the bare conductor is steel core aluminum stranded wire, and the calculation system includes:

[0017] A parameter acquisition unit, used to acquire specification parameters of the bare wire;

[0018] The specific heat capacity calculation unit is used to calculate the specific heat capacity per unit length of bare wire according to the specification parameters of the bare wire:

[0019]

[0020] Where C is the specific heat capacity per unit length of bare wire, m AL is the weight of aluminum per unit length of bare conductor, m AL =ρ AL S AL L, ρ AL is the density of aluminum, S AL is the aluminum cross-sectional area of ​​the bare wire, L is the unit length of the bare wire, c AL is the specific heat capacity of aluminum, m T is the weight of steel per unit length of bare conductor, m T =ρ T S T L, ρ T is the density of steel, S T is the steel cross-sectional area of ​​the bare conductor, c T is the specific heat capacity of steel, W is the mass of bare wire per unit length;

[0021] Thermal transient time constant calculation unit, used to calculate the thermal transient time constant based on the specific heat capacity per unit length of bare wire:

[0022]

[0023] In the formula, θ a is the air environment temperature of the thermal transient process, R is the DC resistance at 20℃, C is the specific heat capacity of the above-mentioned bare wire per unit length, and W is the mass of the above-mentioned bare wire per unit length.

[0024] In a third aspect, the present invention proposes an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for calculating the thermal transient time constant of a bare conductor under standard conditions as described in any embodiment of the present invention is implemented.

[0025] In a fourth aspect, the present invention proposes a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a method for calculating the thermal transient time constant of a bare conductor under standard conditions as described in any embodiment of the present invention.

[0026] In a fifth aspect, the present invention provides a power grid peak regulation method, comprising the following steps:

[0027] Calculating the thermal transient time constant according to the method for calculating the thermal transient time constant of a bare conductor under standard conditions described in any embodiment of the present invention;

[0028] Draw a time-line temperature curve based on the calculated thermal transient time constant;

[0029] A power grid peak regulation strategy is formulated based on the time-line temperature curve.

[0030] In a sixth aspect, the present invention proposes an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a grid peak regulation method as described in any embodiment of the present invention is implemented.

[0031] In a seventh aspect, the present invention proposes a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a power grid peak regulation method as described in any embodiment of the present invention.

[0032] In an eighth aspect, the present invention provides a method for dynamic dispatching of a power grid, comprising the following steps:

[0033] Calculating the thermal transient time constant according to the method for calculating the thermal transient time constant of a bare conductor under standard conditions described in any embodiment of the present invention;

[0034] Determine the short-time overload capacity of the bare conductor based on the calculated thermal transient time constant;

[0035] A dynamic dispatching strategy for the power grid is formulated based on the short-term overload capacity of the bare conductor.

[0036] In a ninth aspect, the present invention proposes an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a method for dynamic dispatching of a power grid as described in any embodiment of the present invention is implemented.

[0037] In a tenth aspect, the present invention proposes a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a method for dynamic dispatching of a power grid as described in any embodiment of the present invention.

[0038] The present invention has the following beneficial effects:

[0039] 1. The present invention provides a method for calculating the thermal transient time constant of a bare conductor under standard conditions. A new method for calculating the thermal transient time constant of a bare conductor is provided. The method can calculate the thermal transient time constant τ of the power grid N-1 transition stage under standard conditions according to the most basic parameters of the conductor. Compared with the previous iterative calculation using numerical calculus, it saves a lot of complicated calculation steps. At the same time, the calculation results can meet the engineering design requirements and the power grid operation and dispatching requirements, greatly improving the design efficiency.

[0040] 2. A power grid peak regulation method of the present invention draws a time-line temperature curve according to the calculated time constant, which can provide accurate, safe and reliable support for power grid peak regulation.

[0041] 3. A power grid dynamic dispatching method of the present invention determines the short-term overload capacity of the bare conductor by calculating the thermal transient time constant, which can provide a simple and effective reference basis for the power grid dynamic dispatching strategy. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is the current carrying capacity change diagram of the transmission line from the normal state to the N-1 state;

[0043] Figure 2 This is a flow chart of a method according to Embodiment 1 of the present invention;

[0044] Figure 3 This is a schematic diagram of the system framework of Embodiment 2 of the present invention;

[0045] Figure 4 This is a flow chart of the method of Embodiment 5 of the present invention;

[0046] Figure 5 An example diagram of a time-line temperature curve drawn in an embodiment of the present invention;

[0047] Figure 6 This is a flow chart of the method of embodiment 8 of the present invention. DETAILED DESCRIPTION

[0048] 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.

[0049] It should be understood that the step numbers used in this document are only for convenience of description and are not intended to limit the order in which the steps are executed.

[0050] It should be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0051] The terms “include” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0052] The term "and / or" means and includes any and all possible combinations of one or more of the associated listed items.

[0053] Embodiment 1:

[0054] See also Figure 2 This embodiment proposes a method for calculating the thermal transient time constant of a bare conductor under standard conditions. Considering that the design specification recommends the use of a unified solar radiation power (1000W / m 2 ) and convection heat dissipation wind speed (0.5m / s), the conductor radiation heat dissipation coefficient and the conductor surface heat absorption coefficient are both taken as 0.9. This setting is called the standard condition. In this way, the time constant of the conventional bare conductor of the overhead line (i.e. steel-core aluminum stranded wire and aluminum-clad steel-core aluminum stranded wire) under standard conditions can be calculated;

[0055] The calculation method proposed in this embodiment includes the following steps:

[0056] Step S101, obtaining specification parameters of the bare wire;

[0057] Step S102: Calculate the specific heat capacity per unit length of the bare wire according to the specification parameters of the bare wire:

[0058]

[0059] Wherein, C is the specific heat capacity of the bare wire per unit length (the unit length in this embodiment is selected as one kilometer) (the amount of heat absorbed (or released) when the temperature of a certain substance per unit mass increases (or decreases) by 1°C, in units of J / (kg.K));

[0060] m AL The weight of aluminum in each kilometer of bare conductor, in kg / km, m AL =ρ AL S AL L, ρ AL is the density of aluminum, ρ AL =2.7×103(kg / m 3 ), S AL is the aluminum cross-sectional area of ​​the bare conductor, in mm 2 , L is the unit length of the bare wire, in this embodiment, it is 1000m, c AL is the specific heat capacity of aluminum, c AL =955J / (kg.K);

[0061] m T The weight of steel in each kilometer of bare conductor, in kg / km, m T =ρ T S T L, ρ T is the density of steel, ρ T =7.85×10 3 (kg / m 3 ), ST is the steel cross-sectional area of ​​the bare conductor, in mm 2 , c T is the specific heat capacity of steel, c T =476J / (kg.K), if it is 20.3%IACS aluminum-clad steel, it is 534;

[0062] W is the mass of bare conductor per kilometer, kg / km;

[0063] S103. Calculate the thermal transient time constant based on the specific heat capacity per unit length of bare wire:

[0064]

[0065] In the formula, θ a is the air environment temperature during the thermal transient process. Assuming that θ a Keep constant, unit is ℃;

[0066] R is the DC resistance at 20°C, in Ω / m;

[0067] C is the specific heat capacity of the above bare wire per kilometer, and W is the mass of the above bare wire per kilometer;

[0068] τ is the ambient temperature θ a The time constant in this case can be expressed in minutes or seconds. Generally, engineering calculations mainly consider the line temperature changes within 30 minutes.

[0069] The method proposed in this embodiment is applicable to conventional bare conductors, i.e., steel core aluminum stranded wire and aluminum clad steel core aluminum stranded wire. For other special and uncommon bare conductors, the parameters of other types of conductors can be converted into equivalent corresponding parameters with a deep understanding of the current carrying capacity calculation principle in this embodiment.

[0070] In order to demonstrate the effectiveness and superiority of the calculation method of the thermal transient time constant proposed in this embodiment, a specific application example and application effect are provided below:

[0071] Select the aluminum-clad steel-core aluminum stranded wire model JL / LB20A-400 / 35 and obtain its specification parameters, including the aluminum cross-sectional area of ​​the bare conductor 390.88mm 2 , the steel (steel core) cross-sectional area of ​​the bare conductor is 34.36mm 2 , 20℃ DC resistance 0.00007177Ω / m, according to the specific heat capacity calculation formula of bare wire per unit length, CW=1136.3J / K, according to the time constant calculation formula, the time constant at ambient temperature 15-40℃ is shown in Table 1 below:

[0072] Table 1: Time constant calculation table for aluminum-clad steel core aluminum stranded wire JL / LB20A-400 / 35

[0073]

[0074] Assuming that at N-1, the current jumps from the initial 500A to 800A in steady state, the initial line temperature and the final steady-state line temperature can be calculated according to the standard formula as shown in Table 2 below:

[0075] Table 2: Initial and steady-state wire temperature of aluminum-clad steel core aluminum stranded wire JL / LB20A-400 / 35

[0076]

[0077] According to the data in the above two tables, when the ambient temperature is between 15℃ and 40℃, the real-time wire temperature (℃) of the conductor is calculated every 1 minute within 30 minutes as shown in Table 3 below:

[0078] Table 3: Real-time line temperature calculated according to the time constant of the method of this embodiment (°C)

[0079]

[0080]

[0081] In the ambient temperature range of 15°C to 40°C, the difference (°C) between the calculation method proposed in this embodiment and the result obtained by the differential precise calculation method (this algorithm is a traditional method) is shown in Table 4:

[0082] Table 4: Difference between the real-time line temperature calculated according to the method of this embodiment and the real-time line temperature accurately calculated by differentiation (°C)

[0083] Time t (minutes) 15℃ 20℃ 25℃ 30℃ 35℃ 40℃ 1 0.028 0.027 0.026 0.026 0.025 0.024 2 0.046 0.045 0.043 0.042 0.041 0.039 3 0.058 0.056 0.054 0.051 0.049 0.046 4 0.065 0.061 0.058 0.055 0.051 0.048 5 0.067 0.063 0.059 0.054 0.050 0.047 6 0.067 0.062 0.057 0.051 0.047 0.042 7 0.064 0.058 0.052 0.046 0.041 0.036 8 0.060 0.053 0.047 0.040 0.034 0.029 9 0.054 0.047 0.040 0.033 0.027 0.021 10 0.048 0.041 0.034 0.026 0.020 0.013 11 0.042 0.034 0.027 0.019 0.012 0.006 12 0.036 0.028 0.020 0.012 0.005 -0.001 13 0.030 0.021 0.013 0.006 -0.002 -0.008 14 0.024 0.015 0.007 0.000 -0.008 -0.014 15 0.018 0.010 0.002 -0.006 -0.013 -0.019 16 0.013 0.005 -0.003 -0.011 -0.018 -0.024 17 0.008 0.000 -0.008 -0.015 -0.022 -0.028 18 0.003 -0.004 -0.012 -0.019 -0.026 -0.031 19 -0.001 -0.008 -0.016 -0.023 -0.029 -0.034 20 -0.004 -0.011 -0.019 -0.025 -0.031 -0.036 21 -0.007 -0.014 -0.021 -0.028 -0.033 -0.038 22 -0.010 -0.017 -0.023 -0.029 -0.035 -0.039 23 -0.012 -0.019 -0.025 -0.031 -0.036 -0.040 24 -0.014 -0.020 -0.026 -0.032 -0.036 -0.040 25 -0.016 -0.022 -0.027 -0.033 -0.037 -0.040 26 -0.017 -0.023 -0.028 -0.033 -0.037 -0.040 27 -0.018 -0.024 -0.029 -0.033 -0.037 -0.040 28 -0.019 -0.024 -0.029 -0.033 -0.036 -0.039 29 -0.020 -0.024 -0.029 -0.033 -0.036 -0.038 30 -0.020 -0.024 -0.029 -0.032 -0.035 -0.037

[0084] It can be seen from the above table that the difference between the real-time line temperature calculated by the time constant calculated by the method of this embodiment and the real-time line temperature accurately calculated by differential is -0.04°C at the minimum and 0.067°C at the maximum. The absolute value of the maximum error does not exceed 0.1°C, which is accurate enough for engineering design and operation scheduling.

[0085] Similarly, according to the method of this embodiment, the time constants of several other commonly used wires in the ambient temperature of 15°C to 40°C are calculated as shown in Table 5:

[0086] Table 5: Time constant calculation table for some commonly used conductors

[0087]

[0088]

[0089] In the ambient temperature range of 15°C to 40°C, the relative percentage of the real-time line temperature calculated by the time constant calculated by the method of this embodiment and the real-time line temperature accurately calculated by differential is shown in Table 6:

[0090] Table 6: Relative percentage of the time constant calculated according to the method of this embodiment and the time constant accurately calculated by differentiation

[0091] Lead wire model 15℃ 20℃ 25℃ 30℃ 35℃ 40℃ JL / LB20A-185 / 30 99.69％ 99.46％ 99.46％ 99.46％ 99.46％ 99.46％ JL / LB20A-240 / 30 99.32％ 99.28％ 99.24％ 99.20％ 99.15％ 99.31％ JL / LB20A-300 / 25 100.76％ 100.71％ 100.67％ 100.80％ 100.75％ 100.71％ JL / LB20A-400 / 35 98.83％ 98.97％ 99.11％ 99.10％ 99.25％ 99.25％ JL / LB20A-500 / 45 98.72％ 98.73％ 98.74％ 98.75％ 98.76％ 98.76％ JL / LB20A-630 / 45 100.75％ 100.73％ 100.71％ 100.57％ 100.54％ 100.51％ JL / LB20A-720 / 50 99.71％ 99.68％ 99.76％ 99.73％ 99.69％ 99.66％ JL / LB20A-800 / 55 99.57％ 99.48％ 99.47％ 99.38％ 99.37％ 99.27％

[0092] From the above table, we can see that the maximum time constant error of JL / LB20A-400 / 35 and JL / LB20A-500 / 45 is about -1.17 to -1.28%. According to Table 4, the maximum absolute value of the real-time wire temperature error calculated by the JL / LB20A-400 / 35 time constant is about 0.067°C, and according to relevant calculations, the absolute value of the real-time wire temperature error calculated by the JL / LB20A-500 / 45 time constant does not exceed 0.08°C. The relative errors of the time constants of other wires are smaller, and it can be inferred that the absolute error of the real-time wire temperature calculated by them is even smaller.

[0093] This embodiment uses analog circuit theory to provide a method for calculating the thermal transient time constant when steel core aluminum stranded wire (or aluminum clad steel core aluminum stranded wire) is used as an overhead conductor. This method can calculate the thermal transient time constant τ under standard conditions in the N-1 transition stage of the power grid based on the most basic parameters of the conductor. Compared with the previous iterative calculation using numerical calculus, it saves a lot of complicated calculation steps. At the same time, the calculation results can meet the engineering design requirements and the power grid operation and dispatching requirements, greatly improving the design efficiency.

[0094] Embodiment 2:

[0095] See also Figure 3 This embodiment proposes a calculation system for the thermal transient time constant of a bare conductor under standard conditions, wherein the standard condition is that the solar radiation power is 1000W / m 2 , the convection heat dissipation wind speed is 0.5m / s, the conductor radiation heat dissipation coefficient and the conductor surface heat absorption coefficient are both 0.9; the bare conductor is steel core aluminum stranded wire, and the calculation system includes:

[0096] A parameter acquisition unit, used to acquire specification parameters of the bare wire, which is used to implement the function of step S101 in the first embodiment, and will not be described in detail here;

[0097] The specific heat capacity calculation unit is used to calculate the specific heat capacity of the bare wire per unit length according to the specification parameters of the bare wire; this unit is used to implement the function of step S102 in the first embodiment, which will not be repeated here

[0098]

[0099] Where C is the specific heat capacity per unit length of bare wire, m AL is the weight of aluminum per unit length of bare conductor, m AL =ρ AL S AL L, ρ AL is the density of aluminum, S AL is the aluminum cross-sectional area of ​​the bare wire, L is the unit length of the bare wire, c AL is the specific heat capacity of aluminum, m T is the weight of steel per unit length of bare conductor, m T =ρ T S T L, ρ T is the density of steel, S T is the steel cross-sectional area of ​​the bare conductor, W is the mass of the bare conductor per unit length;

[0100] The thermal transient time constant calculation unit is used to calculate the thermal transient time constant according to the specific heat capacity per unit length of the bare wire; this unit is used to implement the function of step S103 in the first embodiment, which will not be described in detail here.

[0101]

[0102] In the formula, θ a is the air environment temperature of the thermal transient process, R is the DC resistance at 20℃, C is the specific heat capacity of the above-mentioned bare wire per unit length, and W is the mass of the above-mentioned bare wire per unit length.

[0103] Embodiment three:

[0104] This embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the method for calculating the thermal transient time constant of a bare conductor under standard conditions as described in the first embodiment above is implemented.

[0105] Embodiment 4:

[0106] This embodiment provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the method for calculating the thermal transient time constant of a bare conductor under standard conditions as described in the first embodiment above is implemented.

[0107] Embodiment five:

[0108] See also Figure 4 This embodiment provides a power grid peak load regulation method, comprising the following steps:

[0109] S201, calculating the thermal transient time constant according to the method for calculating the thermal transient time constant of a bare conductor under standard conditions described in the first embodiment;

[0110] S202, draw a time-line temperature curve according to the calculated thermal transient time constant, and the drawn time-line temperature curve is as follows: Figure 5 As shown, Figure 5 The figure shows an example of a time-wire temperature curve of a bare conductor of model JL / LB20A-400 / 35 drawn based on the calculated thermal transient time constant;

[0111] S203: Formulate a power grid peak regulation strategy based on the time-line temperature curve.

[0112] The power grid peak regulation method proposed in this embodiment draws a time-line temperature curve (or table) according to the calculated time constant, which can provide accurate, safe and reliable support for power grid peak regulation.

[0113] Embodiment six:

[0114] This embodiment proposes an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a power grid peak regulation method as described in the fifth embodiment is implemented.

[0115] Embodiment seven:

[0116] This embodiment provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, a power grid peak regulation method as described in the fifth embodiment is implemented.

[0117] Embodiment eight:

[0118] See also Figure 6 This embodiment proposes a power grid dynamic dispatching method, comprising the following steps:

[0119] S301, calculating the thermal transient time constant according to the method for calculating the thermal transient time constant of a bare conductor under standard conditions described in the first embodiment;

[0120] S302, determining the short-time overload capacity of the bare wire according to the calculated thermal transient time constant;

[0121] S303: formulating a dynamic dispatching strategy for a power grid based on the short-term overload capacity of the bare conductor.

[0122] The power grid dynamic dispatching method proposed in this embodiment determines the short-term overload capacity of the bare conductor by calculating the thermal transient time constant, which can provide a simple and effective reference basis for the power grid dynamic dispatching strategy.

[0123] Embodiment nine:

[0124] This embodiment proposes an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a method for dynamic scheduling of a power grid as described in the eighth embodiment above is implemented.

[0125] Embodiment ten:

[0126] The present invention proposes a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a power grid dynamic scheduling method as described in the above-mentioned embodiment eight.

[0127] Those of ordinary skill in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented in a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0128] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0129] In several embodiments provided in the present application, if any function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory; hereinafter referred to as: ROM), random access memory (Random Access Memory; hereinafter referred to as: RAM), disk or optical disk, and other media that can store program codes.

[0130] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for calculating the thermal transient time constant of a bare conductor under standard conditions, wherein the standard condition is a solar radiation power of 1000 W / m 2 , the convection heat dissipation wind speed is 0.5m / s, the conductor radiation heat dissipation coefficient and the conductor surface heat absorption coefficient are both 0.9; the bare conductor is a steel core aluminum stranded wire, characterized in that, The calculation method includes the following steps: Get the specification parameters of bare wire; According to the specification parameters of the bare wire, calculate the specific heat capacity per unit length of the bare wire: Where C is the specific heat capacity per unit length of bare wire, m AL is the weight of aluminum per unit length of bare conductor, m AL =ρ AL S AL L, ρ AL is the density of aluminum, S AL is the aluminum cross-sectional area of ​​the bare wire, L is the unit length of the bare wire, c AL is the specific heat capacity of aluminum, m T is the weight of steel per unit length of bare conductor, m T =ρ T S T L, ρ T is the density of steel, S T is the steel cross-sectional area of ​​the bare conductor, c T is the specific heat capacity of steel, W is the mass of bare wire per unit length; Calculate the thermal transient time constant based on the specific heat capacity per unit length of bare wire: In the formula, θ a is the air environment temperature of the thermal transient process, R is the DC resistance at 20℃, C is the specific heat capacity of the bare wire per unit length, and W is the mass of the bare wire per unit length.

2. A calculation system for the thermal transient time constant of a bare conductor under standard conditions, wherein the standard condition is a solar radiation power of 1000 W / m 2 , the convection cooling wind speed is 0.5m / s, the conductor radiation cooling coefficient and the conductor surface heat absorption coefficient are both 0.9; The bare conductor is a steel core aluminum stranded wire, characterized in that: The computing system includes: A parameter acquisition unit, used to acquire specification parameters of the bare wire; The specific heat capacity calculation unit is used to calculate the specific heat capacity per unit length of bare wire according to the specification parameters of the bare wire: Where C is the specific heat capacity per unit length of bare wire, m AL is the weight of aluminum per unit length of bare conductor, m AL =ρ AL S AL L, ρ AL is the density of aluminum, S AL is the aluminum cross-sectional area of ​​the bare wire, L is the unit length of the bare wire, c AL is the specific heat capacity of aluminum, m T is the weight of steel per unit length of bare conductor, m T =ρ T S T L, ρ T is the density of steel, S T is the steel cross-sectional area of ​​the bare conductor, c T is the specific heat capacity of steel, W is the mass of bare wire per unit length; Thermal transient time constant calculation unit, used to calculate the thermal transient time constant based on the specific heat capacity per unit length of bare wire: In the formula, θ a is the air environment temperature of the thermal transient process, R is the DC resistance at 20℃, C is the specific heat capacity of the bare wire per unit length, and W is the mass of the bare wire per unit length.

3. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the method for calculating the thermal transient time constant of a bare conductor under standard conditions as described in claim 1 is implemented.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for calculating the thermal transient time constant of a bare conductor under standard conditions as claimed in claim 1 is implemented.

5. A power grid peak regulation method, characterized in that: The following steps are involved: Calculate the thermal transient time constant according to the method for calculating the thermal transient time constant of a bare conductor under standard conditions as described in claim 1; Draw a time-line temperature curve based on the calculated thermal transient time constant; A power grid peak regulation strategy is formulated based on the time-line temperature curve.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the power grid peak regulation method as described in claim 5 is implemented.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, a power grid peak regulation method as described in claim 5 is implemented.

8. A method for dynamic dispatching of a power grid, characterized in that: The following steps are involved: Calculate the thermal transient time constant according to the method for calculating the thermal transient time constant of a bare conductor under standard conditions as described in claim 1; Determine the short-time overload capacity of the bare conductor based on the calculated thermal transient time constant; A dynamic dispatching strategy for the power grid is formulated based on the short-term overload capacity of the bare conductor.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, a power grid dynamic scheduling method as described in claim 8 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, a power grid dynamic scheduling method as claimed in claim 8 is implemented.

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