A composite insulating cross arm shed structure and parameter determination method and system thereof

Abstract

The present invention relates to a composite insulating cross-arm shed structure and a method and system for determining its parameters, comprising a core rod, hardware provided at both ends of the core rod, a plurality of sheds and a sheath covering the surface of the core rod; the plurality of sheds are arranged at equal intervals on the core rod, the sheath covers between two adjacent sheds and between the shed and the hardware; the sheds of the composite insulating cross-arm shed structure have an shed extension of 12 mm, and a creepage coefficient of 1.22. The present invention sets the shed extension of the composite insulating cross-arm shed structure to 12 mm and the creepage coefficient to 1.22, so as to improve the negative polarity lightning impulse discharge performance of the shed group structure of the composite insulating cross-arm.

Description

Technical Field

[0001] The invention relates to the technical field of insulation structure design, and in particular to a composite insulation cross arm shed structure and a method and system for determining parameters thereof. Background Art

[0002] Distribution networks are threatened not only by direct lightning strikes but also by induced lightning strikes due to the generally low insulation level of their lines. The lightning impulse flashover voltage of the insulators used on traditional iron crossarms is relatively low, and their lightning protection performance is poor, resulting in a high lightning trip rate for distribution network lines, and even possible line breakage due to lightning strikes.

[0003] Composite insulated crossarms have begun to attract widespread attention due to their good insulation performance, high strength, light weight, high pollution flashover voltage, easy manufacturing, transportation, installation and maintenance, etc., which is beneficial to improving the lightning protection performance of distribution networks.

[0004] The umbrella group structure of the composite insulation crossarm of the distribution network is mainly equal umbrella extension. Many users and manufacturers, based on the operating experience of traditional porcelain insulators, simply stipulate the required creepage distance to ensure that the standard lightning impulse withstand voltage of the composite crossarm meets the requirements, and lack scientific basis for the value of the umbrella skirt structure parameters. Due to the simple manufacturing process, by changing parameters such as umbrella extension and umbrella spacing, manufacturers can almost produce composite crossarms with any creepage distance required by users under a given installation length. Because the 50% breakdown voltage of the negative polarity lightning impulse of the composite insulation crossarm of the distribution network under rain conditions drops seriously, the umbrella group structure has a significant impact on the arc path. Therefore, under the same structural length conditions, the difference in structural parameters makes the 50% breakdown voltage of the negative polarity lightning impulse of the composite insulation crossarm of the distribution network under rain conditions vary greatly.

[0005] How to achieve parameter optimization design of shed structure to improve negative polarity lightning impulse discharge performance of shed group structure with composite insulation cross arm. Summary of the invention

[0006] In view of this, the present invention provides a composite insulating crossarm shed structure and a parameter determination method and system thereof, so as to achieve parameter optimization design of the shed structure and improve the negative polarity lightning impulse discharge performance of the shed group structure of the composite insulating crossarm.

[0007] To achieve the above object, the present invention provides the following solutions:

[0008] A composite insulating cross-arm shed structure, comprising a core rod, hardware arranged at both ends of the core rod, and a plurality of sheds and a sheath covering the surface of the core rod;

[0009] A plurality of sheds are arranged at equal intervals on the core rod, and the sheath covers between two adjacent sheds and between the shed and the fittings;

[0010] The umbrella extension of the composite insulating cross-arm umbrella skirt structure is 12 mm, the creepage coefficient of the composite insulating cross-arm umbrella skirt structure is 1.22, the umbrella extension is the radial distance between the outer edge of the umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the sheath, and the creepage coefficient is the ratio of the creepage distance of the composite insulating cross-arm umbrella skirt structure to the insulation distance.

[0011] Optionally, the umbrella spacing of the composite insulating cross-arm umbrella skirt structure is 120 mm, and the end umbrella spacing of the composite insulating cross-arm umbrella skirt structure is 85 mm. The umbrella spacing is the axial distance between any position on any umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the corresponding position on the adjacent umbrella skirt of the umbrella skirt. The end umbrella spacing is the axial distance between the hardware of the composite insulating cross-arm umbrella skirt structure and the umbrella skirt closest to the hardware.

[0012] Optionally, the thickness of the sheath is 6 mm.

[0013] A method for determining parameters of a composite insulating cross arm shed structure, the method for determining parameters being applied to the composite insulating cross arm shed structure, the method for determining parameters comprising the following steps:

[0014] A negative polarity lightning impulse flashover test is conducted under rain conditions to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the umbrella extension of a composite insulating cross-arm umbrella skirt structure as a first relationship curve, and to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the creepage coefficient of the composite insulating cross-arm umbrella skirt structure as a second relationship curve; the umbrella extension is the radial distance between the outer edge of the umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the sheath; the creepage coefficient is the ratio of the creepage distance of the composite insulating cross-arm umbrella skirt structure to the insulation distance;

[0015] Based on the first relationship curve, determining the umbrella extension of the composite insulation cross arm umbrella skirt structure when the lightning impulse 50% breakdown voltage is optimal as the parameter value of the umbrella extension;

[0016] Based on the second relationship curve, the creepage coefficient of the composite insulating crossarm shed structure when the lightning impulse 50% breakdown voltage is optimal is determined as the parameter value of the creepage coefficient.

[0017] Optionally, the umbrella extension of the composite insulating cross arm umbrella skirt structure when the lightning impulse 50% breakdown voltage is optimal is determined based on the first relationship curve as the parameter value of the umbrella extension, and then further includes:

[0018] According to the parameter value of the umbrella extension, use the formula Determine the parameter value of the umbrella spacing of the composite insulating cross-arm umbrella skirt structure; wherein K represents the ratio of the umbrella spacing to the umbrella extension, K=10, S1 represents the umbrella spacing of the composite insulating cross-arm umbrella skirt structure, P represents the umbrella extension of the composite insulating cross-arm umbrella skirt structure, and the umbrella spacing is the axial distance between any position on any umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the corresponding position on the adjacent umbrella skirt of the umbrella skirt.

[0019] Optionally, the step of determining the creepage coefficient of the composite insulating crossarm shed structure when the lightning impulse 50% breakdown voltage is optimal based on the second relationship curve as a parameter value of the creepage coefficient further includes:

[0020] According to the parameter values ​​of creepage coefficient, umbrella spacing and umbrella extension, the solution formula is used Determine a parameter value of an end shed spacing of a composite insulating cross-arm shed structure, wherein the end shed spacing is an axial distance between a fitting of the composite insulating cross-arm shed structure and the shed closest to the fitting;

[0021] Wherein, CF represents the creepage coefficient of the composite insulating cross-arm shed structure, d represents the insulation distance of the composite insulating cross-arm shed structure, and the insulation distance is the axial distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure, that is, d=2×S2+(N-1)×S1, wherein S2 represents the end shed spacing of the composite insulating cross-arm shed structure, N represents the number of sheds included in the composite insulating cross-arm shed structure, and l represents the creepage distance of the composite insulating cross-arm shed structure, and the creepage distance is the shortest distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure along the shed and the sheath surface, that is, α represents the umbrella inclination angle, which is the angle between the surface of the umbrella skirt and the vertical line of the core rod, and α=0.25 degrees.

[0022] A parameter determination system for a composite insulating cross arm shed structure, the parameter determination system:

[0023] A relationship curve establishment module is used to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the umbrella extension of a composite insulating cross-arm umbrella skirt structure by using a negative polarity lightning impulse flashover test under rain conditions as a first relationship curve, and to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the creepage coefficient of the composite insulating cross-arm umbrella skirt structure as a second relationship curve;

[0024] An umbrella extension determination module is used to determine the umbrella extension of the composite insulation cross arm umbrella skirt structure when the lightning impulse 50% breakdown voltage is optimal based on the first relationship curve, as a parameter value of the umbrella extension; the umbrella extension is the radial distance between the outer edge of the umbrella skirt of the composite insulation cross arm umbrella skirt structure and the sheath;

[0025] A creepage coefficient determination module is used to determine the creepage coefficient of the composite insulating cross-arm shed structure when the lightning impulse 50% breakdown voltage is optimal based on the second relationship curve, as a parameter value of the creepage coefficient; the creepage coefficient is the ratio of the creepage distance of the composite insulating cross-arm shed structure to the insulation distance.

[0026] Optionally, the parameter determination system further includes:

[0027] The umbrella spacing determination module is used to determine the distance between the umbrellas according to the parameter value of the umbrella extension using the formula Determine the parameter value of the umbrella spacing of the composite insulating cross-arm umbrella skirt structure; wherein K represents the ratio of the umbrella spacing to the umbrella extension, K=10, S1 represents the umbrella spacing of the composite insulating cross-arm umbrella skirt structure, P represents the umbrella extension of the composite insulating cross-arm umbrella skirt structure, and the umbrella spacing is the axial distance between any position on any umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the corresponding position on the adjacent umbrella skirt of the umbrella skirt.

[0028] Optionally, the parameter determination system further includes:

[0029] The module for determining the distance between end umbrellas is used to solve the formula according to the parameter values ​​of creepage coefficient, umbrella distance and umbrella extension. Determine a parameter value of an end shed spacing of a composite insulating cross-arm shed structure, wherein the end shed spacing is an axial distance between a fitting of the composite insulating cross-arm shed structure and the shed closest to the fitting;

[0030] Wherein, CF represents the creepage coefficient of the composite insulating cross-arm shed structure, d represents the insulation distance of the composite insulating cross-arm shed structure, and the insulation distance is the axial distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure, that is, d=2×S2+(N-1)×S1, wherein S2 represents the end shed spacing of the composite insulating cross-arm shed structure, N represents the number of sheds included in the composite insulating cross-arm shed structure, and l represents the creepage distance of the composite insulating cross-arm shed structure, and the creepage distance is the shortest distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure along the shed and the sheath surface, that is, α represents the umbrella inclination angle, which is the angle between the surface of the umbrella skirt and the vertical line of the core rod, and α=0.25 degrees.

[0031] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0032] The present invention discloses a composite insulating cross-arm shed structure, comprising a core rod, hardware provided at both ends of the core rod, a plurality of sheds and a sheath covering the surface of the core rod; the plurality of sheds are arranged at equal intervals on the core rod, the sheath covers between two adjacent sheds and between the shed and the hardware; the sheds of the composite insulating cross-arm shed structure have an shed extension of 12 mm, and a creepage coefficient of 1.22. The present invention sets the shed extension of the composite insulating cross-arm shed structure to 12 mm and a creepage coefficient of 1.22, so as to improve the negative polarity lightning impulse discharge performance of the shed group structure of the composite insulating cross-arm.

[0033] The present invention also discloses a method and system for determining parameters of a composite insulating cross-arm shed structure, which optimizes the parameters of the composite insulating cross-arm shed structure based on the characteristics of rain-induced lightning impulse discharge, so as to improve the negative polarity lightning impulse discharge performance of the shed group structure of the composite insulating cross-arm. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1 A schematic structural diagram of a composite insulating cross arm shed structure provided in Example 1 of the present invention;

[0036] Figure 2 A flow chart of a method for determining parameters of a composite insulating crossarm shed structure provided in Example 2 of the present invention;

[0037] Figure 3 A first relationship curve diagram provided in Example 2 of the present invention;

[0038] Figure 4 This is a second relationship curve diagram provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0039] 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.

[0040] The object of the present invention is to provide a composite insulating cross arm shed structure and a parameter determination method and system thereof, so as to realize parameter optimization design of the shed structure and improve the negative polarity lightning impulse discharge performance of the shed group structure of the composite insulating cross arm.

[0041] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] like Figure 1 As shown in the figure, the composite insulating cross-arm umbrella skirt structure includes a core rod, hardware at both ends of the core rod, and an umbrella skirt and a sheath covering the outside of the core rod. The umbrella skirt part is composed of a plurality of umbrellas with equal extension. A standard negative polarity lightning impulse flashover test is adopted under rain conditions to establish a relationship curve between the lightning impulse 50% breakdown voltage and the composite insulating cross-arm umbrella extension and creepage coefficient of different umbrella group structures, and then the optimized structural parameters of the composite insulating cross-arm umbrella group are as follows: the sheath thickness is 6mm; the umbrella spacing between adjacent umbrellas is 120mm; the umbrella extension is 12mm; the creepage coefficient of the composite insulating cross-arm is 1.22.

[0043] Example 2

[0044] like Figure 2 As shown, the present invention also provides a method for determining parameters of a composite insulating cross-arm shed structure, the parameter determination method is applied to the composite insulating cross-arm shed structure, and the parameter determination method comprises the following steps:

[0045] Step 201, a negative polarity lightning impulse flashover test is performed under rain conditions to establish a relationship curve between the lightning impulse 50% breakdown voltage and the umbrella extension of the composite insulation cross arm umbrella skirt structure as a first relationship curve, such as Figure 3 As shown, a relationship curve between the 50% breakdown voltage of a lightning impulse and the creepage coefficient of the composite insulation cross arm shed structure is established as the second relationship curve, such as Figure 4 As shown;

[0046] Step 202: Based on the first relationship curve, determine the umbrella extension of the composite insulation cross arm umbrella skirt structure when the lightning impulse 50% breakdown voltage is optimal, as the parameter value of the umbrella extension.

[0047] Under the same umbrella spacing conditions, the distribution network composite insulation cross-arm umbrella with different umbrella skirt structural parameters extends P and rains under the condition of negative polarity lightning impulse 50% breakdown voltage U (hereinafter referred to as U 50％ , unit kV) is shown in the following figure Figure 2 As shown, the thickness of the sheath is 6 mm, the distance S1 between adjacent umbrellas is 120 mm, and the distance S2 between the end umbrellas is 85 mm.

[0048] Depend on Figure 3It can be seen that under the same umbrella spacing conditions, the umbrella extension P has an effect on the negative polarity U of the composite insulation cross arm of the distribution network under rain conditions. 50％ The influence of U is quite obvious. 50％ It increases as the umbrella's extension P increases.

[0049] Therefore, by Figure 3 The analysis shows that for the composite insulating cross arm of the distribution network in the embodiment, when the umbrella extension P is 12 mm in the rain, its negative polarity lightning impulse discharge characteristics are optimal.

[0050] Step 203: Based on the second relationship curve, determine the creepage coefficient of the composite insulating cross-arm shed structure when the lightning impulse 50% breakdown voltage is optimal, as a parameter value of the creepage coefficient.

[0051] Reference Figure 4 , negative polarity U 50％ It increases with the increase of the creepage coefficient CF of the composite insulation cross arm. In the case of rain, when the creepage coefficient CF is 1.22, that is, when the umbrella extends P to 12mm, the negative polarity lightning impulse discharge characteristics are the best, and the lightning impulse flashover voltage U 50％ can reach the maximum value.

[0052] The above research results show that the umbrella group structure parameters of the composite insulation cross-arm of the distribution network are directly related to the 50% breakdown voltage of the negative polarity lightning impulse under rain conditions, and show a certain regularity. Reasonable optimization and design of the umbrella group structure parameters of the composite insulation cross-arm can greatly improve the lightning impulse flashover voltage of the composite insulation cross-arm of the distribution network, thereby improving the lightning protection performance of the composite insulation cross-arm of the distribution network.

[0053] Exemplarily on this basis, the embodiment of the present invention further provides a method for determining the umbrella spacing and the end umbrella spacing.

[0054] The method for determining the distance between umbrellas is as follows: Based on the parameter value of the umbrella extension, use the formula Determine the parameter value of the umbrella spacing of the composite insulating cross-arm umbrella skirt structure; wherein K represents the ratio of the umbrella spacing to the umbrella extension, K=10, S1 represents the umbrella spacing of the composite insulating cross-arm umbrella skirt structure, P represents the umbrella extension of the composite insulating cross-arm umbrella skirt structure, and the umbrella spacing is the axial distance between any position on any umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the corresponding position on the adjacent umbrella skirt of the umbrella skirt.

[0055] The method for determining the distance between the end umbrellas is as follows: Based on the parameter values ​​of the creepage coefficient, the parameter values ​​of the distance between the umbrellas, and the parameter values ​​of the umbrella extension, the solution formula is used. Determine the parameter value of the end shed spacing of the composite insulating cross-arm shed structure, the end shed spacing is the axial distance between the hardware of the composite insulating cross-arm shed structure and the shed closest to the hardware; wherein CF represents the creepage coefficient of the composite insulating cross-arm shed structure, d represents the insulation distance of the composite insulating cross-arm shed structure, the insulation distance is the axial distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure, that is, d=2×S2+(N-1)×S1, wherein S2 represents the end shed spacing of the composite insulating cross-arm shed structure, N represents the number of sheds included in the composite insulating cross-arm shed structure, l represents the creepage distance of the composite insulating cross-arm shed structure, the creepage distance is the shortest distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure along the shed and the sheath surface, that is, α represents the umbrella inclination angle, which is the angle between the surface of the umbrella skirt and the vertical line of the core rod, and α=0.25 degrees.

[0056] The principle of determining the umbrella spacing and the end umbrella spacing is:

[0057] 1. Creepage coefficient CF: The creepage coefficient CF is a parameter for comprehensively checking the total density of creepage distance of insulating crossarms. Its formula is:

[0058] Where: l is the creepage distance of the insulating cross arm;

[0059] d——Insulation distance of insulating crossarm.

[0060] It can be seen from the second relationship curve that when the CF value is about 1.22, its negative polarity flashover voltage under rain has excellent performance.

[0061] 2. The ratio of umbrella spacing to umbrella extension: The ratio of umbrella spacing to umbrella extension is the ratio of the vertical distance between two identical points of two consecutive umbrellas with the same diameter (umbrella spacing s) and the maximum umbrella extension (p), and the formula is s / p.

[0062] Through a large number of experiments, it is known that when the s / p value is around 10, its negative polarity flashover voltage under rain has excellent performance.

[0063] 3. Creepage distance to spacing ratio: d is the straight-line air distance between two points on the insulating crossarm or between one point and another point on the metal attachment. l1 is the creepage distance between the bright points on the above side. l1 / d is the maximum value of the ratio between the two obtained from the intended cross section of the insulating crossarm.

[0064] For checking the risk of arc bridging creepage distances in the presence of dry zones or uneven hydrophobicity, the creepage distance to straight-line distance ratio is a parameter that focuses more on checking the local umbrella shape. This parameter is crucial for avoiding contamination in deep and narrow local areas.

[0065] Through experiments, we know that when the l1 / d value is around 1.245 (that is, when the umbrella is extended to 12mm), its negative polarity flashover voltage performance in rain is excellent.

[0066] 4. Umbrella inclination angle: In the umbrella section, the angle between the shed surface and the vertical line perpendicular to the cross arm is the umbrella inclination angle α. Since the insulating body is horizontal after the insulation cross arm is installed, in order not to hinder the natural cleaning of water on both sides of the shed, the angle α should be less than 20°.

[0067] The embodiment of the present invention adopts the design of α=2.5°, mainly because of the consideration of the thickness of the cross arm shed and the processability and economy in the manufacturing process. The hydrophobic effect is in line with expectations.

[0068] Example 3

[0069] Embodiment 3 of the present invention provides a parameter determination system for a composite insulating cross arm shed structure, wherein the parameter determination system:

[0070] A relationship curve establishment module is used to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the umbrella extension of a composite insulating cross-arm umbrella skirt structure by using a negative polarity lightning impulse flashover test under rain conditions as a first relationship curve, and to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the creepage coefficient of the composite insulating cross-arm umbrella skirt structure as a second relationship curve;

[0071] An umbrella extension determination module is used to determine the umbrella extension of the composite insulation cross arm umbrella skirt structure when the lightning impulse 50% breakdown voltage is optimal based on the first relationship curve, as a parameter value of the umbrella extension; the umbrella extension is the radial distance between the outer edge of the umbrella skirt of the composite insulation cross arm umbrella skirt structure and the sheath;

[0072] A creepage coefficient determination module is used to determine the creepage coefficient of the composite insulating cross-arm shed structure when the lightning impulse 50% breakdown voltage is optimal based on the second relationship curve, as a parameter value of the creepage coefficient; the creepage coefficient is the ratio of the creepage distance of the composite insulating cross-arm shed structure to the insulation distance.

[0073] The parameter determination system also includes:

[0074] The umbrella spacing determination module is used to determine the distance between the umbrellas according to the parameter value of the umbrella extension using the formula Determine the parameter value of the umbrella spacing of the composite insulating cross-arm umbrella skirt structure; wherein K represents the ratio of the umbrella spacing to the umbrella extension, K=10, S1 represents the umbrella spacing of the composite insulating cross-arm umbrella skirt structure, P represents the umbrella extension of the composite insulating cross-arm umbrella skirt structure, and the umbrella spacing is the axial distance between any position on any umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the corresponding position on the adjacent umbrella skirt of the umbrella skirt.

[0075] The parameter determination system also includes:

[0076] The module for determining the distance between end umbrellas is used to solve the formula according to the parameter values ​​of creepage coefficient, umbrella distance and umbrella extension. Determine a parameter value of an end shed spacing of a composite insulating cross-arm shed structure, wherein the end shed spacing is an axial distance between a fitting of the composite insulating cross-arm shed structure and the shed closest to the fitting;

[0077] Wherein, CF represents the creepage coefficient of the composite insulating cross-arm shed structure, d represents the insulation distance of the composite insulating cross-arm shed structure, and the insulation distance is the axial distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure, that is, d=2×S2+(N-1)×S1, wherein S2 represents the end shed spacing of the composite insulating cross-arm shed structure, N represents the number of sheds included in the composite insulating cross-arm shed structure, and l represents the creepage distance of the composite insulating cross-arm shed structure, and the creepage distance is the shortest distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure along the shed and the sheath surface, that is, α represents the umbrella inclination angle, which is the angle between the surface of the umbrella skirt and the vertical line of the core rod, and α=0.25 degrees.

[0078] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0079] The present invention discloses a heterogeneous electric vehicle aggregation control method and system, the method comprising the following steps: within the scheduling period, obtaining the power data and parameter data of each electric vehicle participating in charging at each sampling moment; the parameter data includes the battery capacity and the charging power range; respectively substituting the power data and parameter data obtained within the scheduling period into the aggregation model to obtain the electric vehicle load at each sampling moment output by the aggregation model; according to the difference between the target scheduling power and the electric vehicle load at each sampling moment, using the sliding mode control method to determine the charging power coefficient at the next scheduling moment; and adjusting the charging power of the charging pile according to the charging power coefficient. The aggregation model and sliding mode control of the present invention overcome the difficulties brought by the parameter heterogeneity and charging randomness of electric vehicles to the consumption scheduling, and realize the full scheduling of electric vehicle clusters to consume the target scheduling power given by the power grid side to overcome the fluctuation of clean energy. The present invention realizes the consumption of the fluctuation of clean energy based on the electric vehicle cluster with parameter heterogeneity and charging randomness.

[0080] The umbrella group structure optimization design of the present invention is mainly optimized for the umbrella extension parameters, and a rain discharge test is performed on it using a standard negative polarity lightning impulse flashover test, and the relationship between the lightning impulse 50% breakdown voltage under rain conditions and the extension and creepage coefficient of the distribution network composite insulation cross arm umbrellas of different umbrella group structures is established, and the distribution network composite insulation cross arm umbrella group structure parameters with the best rain lightning impulse discharge characteristics are provided. The umbrella group structure parameters after the optimized design enable the distribution network composite insulation cross arm to have excellent lightning protection performance under the condition of the same structure length, and can greatly improve the lightning impulse 50% breakdown voltage of the distribution network composite cross arm under rain conditions.

[0081] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0082] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for determining parameters of a composite insulating cross arm shed structure, characterized in that: The parameter determination method is applied to a composite insulating cross-arm shed structure, which comprises a core rod, hardware arranged at both ends of the core rod, and a plurality of sheds and a sheath covering the surface of the core rod; A plurality of sheds are arranged at equal intervals on the core rod, and the sheath covers between two adjacent sheds and between the shed and the fittings; The umbrella extension of the composite insulation cross arm umbrella skirt structure is 12 mm, the creepage coefficient of the composite insulation cross arm umbrella skirt structure is 1.22, the umbrella extension is the radial distance between the outer edge of the umbrella skirt of the composite insulation cross arm umbrella skirt structure and the sheath, and the creepage coefficient is the ratio of the creepage distance of the composite insulation cross arm umbrella skirt structure to the insulation distance; The parameter determination method comprises the following steps: A negative polarity lightning impulse flashover test is conducted under rain conditions to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the umbrella extension of a composite insulating cross-arm umbrella skirt structure as a first relationship curve, and to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the creepage coefficient of the composite insulating cross-arm umbrella skirt structure as a second relationship curve; the umbrella extension is the radial distance between the outer edge of the umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the sheath; the creepage coefficient is the ratio of the creepage distance of the composite insulating cross-arm umbrella skirt structure to the insulation distance; Based on the first relationship curve, determining the umbrella extension of the composite insulation cross arm umbrella skirt structure when the lightning impulse 50% breakdown voltage is optimal as the parameter value of the umbrella extension; Based on the second relationship curve, determining the creepage coefficient of the composite insulation cross arm shed structure when the lightning impulse 50% breakdown voltage is optimal, as the parameter value of the creepage coefficient; The method further comprises: determining the umbrella extension of the composite insulation cross arm umbrella skirt structure when the lightning impulse 50% breakdown voltage is optimal based on the first relationship curve as the parameter value of the umbrella extension; and then: According to the parameter value of the umbrella extension, use the formula Determine the parameter value of the umbrella spacing of the composite insulating cross-arm umbrella skirt structure; wherein K represents the ratio of the umbrella spacing to the umbrella extension, K=10, S1 represents the umbrella spacing of the composite insulating cross-arm umbrella skirt structure, P represents the umbrella extension of the composite insulating cross-arm umbrella skirt structure, and the umbrella spacing is the axial distance between any position on any umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the corresponding position on the adjacent umbrella skirt of the umbrella skirt; The method further comprises: determining the creepage coefficient of the composite insulating cross arm shed structure when the lightning impulse 50% breakdown voltage is optimal based on the second relationship curve as the parameter value of the creepage coefficient; and then: According to the parameter values ​​of creepage coefficient, umbrella spacing and umbrella extension, the solution formula is used Determine a parameter value of an end shed spacing of a composite insulating cross-arm shed structure, wherein the end shed spacing is an axial distance between a fitting of the composite insulating cross-arm shed structure and the shed closest to the fitting; Wherein, CF represents the creepage coefficient of the composite insulating cross-arm shed structure, d represents the insulation distance of the composite insulating cross-arm shed structure, and the insulation distance is the axial distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure, that is, d=2×S2+(N-1)×S1, wherein S2 represents the end shed spacing of the composite insulating cross-arm shed structure, N represents the number of sheds included in the composite insulating cross-arm shed structure, and l represents the creepage distance of the composite insulating cross-arm shed structure, and the creepage distance is the shortest distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure along the shed and the sheath surface, that is, α represents the umbrella inclination angle, which is the angle between the surface of the umbrella skirt and the vertical line of the core rod, and α=0.25 degrees.

2. The method for determining parameters of a composite insulating crossarm shed structure according to claim 1, characterized in that: The umbrella spacing of the composite insulating cross-arm umbrella skirt structure is 120 mm, the end umbrella spacing of the composite insulating cross-arm umbrella skirt structure is 85 mm, the umbrella spacing is the axial distance between any position on any umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the corresponding position on the adjacent umbrella skirt of the umbrella skirt, and the end umbrella spacing is the axial distance between the hardware of the composite insulating cross-arm umbrella skirt structure and the umbrella skirt closest to the hardware.

3. The method for determining parameters of a composite insulating crossarm shed structure according to claim 1, characterized in that: The thickness of the sheath is 6 mm.

4. A parameter determination system for a composite insulating cross arm shed structure, characterized in that: The parameter determination system: A relationship curve establishment module is used to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the umbrella extension of a composite insulating cross-arm umbrella skirt structure by using a negative polarity lightning impulse flashover test under rain conditions as a first relationship curve, and to establish a relationship curve between the 50% breakdown voltage of a lightning impulse and the creepage coefficient of the composite insulating cross-arm umbrella skirt structure as a second relationship curve; An umbrella extension determination module is used to determine the umbrella extension of the composite insulation cross arm umbrella skirt structure when the lightning impulse 50% breakdown voltage is optimal based on the first relationship curve, as a parameter value of the umbrella extension; the umbrella extension is the radial distance between the outer edge of the umbrella skirt of the composite insulation cross arm umbrella skirt structure and the sheath; A creepage coefficient determination module, used to determine the creepage coefficient of the composite insulation cross arm shed structure when the lightning impulse 50% breakdown voltage is optimal based on the second relationship curve, as a parameter value of the creepage coefficient; The creepage coefficient is the ratio of the creepage distance to the insulation distance of the composite insulating cross arm shed structure; The parameter determination system also includes: The umbrella spacing determination module is used to determine the distance between the umbrellas according to the parameter value of the umbrella extension using the formula Determine the parameter value of the umbrella spacing of the composite insulating cross-arm umbrella skirt structure; wherein K represents the ratio of the umbrella spacing to the umbrella extension, K=10, S1 represents the umbrella spacing of the composite insulating cross-arm umbrella skirt structure, P represents the umbrella extension of the composite insulating cross-arm umbrella skirt structure, and the umbrella spacing is the axial distance between any position on any umbrella skirt of the composite insulating cross-arm umbrella skirt structure and the corresponding position on the adjacent umbrella skirt of the umbrella skirt; The parameter determination system also includes: The module for determining the distance between end umbrellas is used to solve the formula according to the parameter values ​​of creepage coefficient, umbrella distance and umbrella extension. Determine a parameter value of an end shed spacing of a composite insulating cross-arm shed structure, wherein the end shed spacing is an axial distance between a fitting of the composite insulating cross-arm shed structure and the shed closest to the fitting; Wherein, CF represents the creepage coefficient of the composite insulating cross-arm shed structure, d represents the insulation distance of the composite insulating cross-arm shed structure, and the insulation distance is the axial distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure, that is, d=2×S2+(N-1)×S1, wherein S2 represents the end shed spacing of the composite insulating cross-arm shed structure, N represents the number of sheds included in the composite insulating cross-arm shed structure, and 1 represents the creepage distance of the composite insulating cross-arm shed structure, and the creepage distance is the shortest distance between the hardware at both ends of the core rod of the insulating cross-arm shed structure along the shed and the sheath surface, that is, α represents the umbrella inclination angle, which is the angle between the surface of the umbrella skirt and the vertical line of the core rod, and α=0.25 degrees.

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