A method and device for predicting the self-oscillation fundamental frequency of a dry-type air-core reactor

Abstract

The present application discloses a method and device for predicting the natural fundamental frequency of a dry-type air-core reactor, the method comprising obtaining first parameter information about the reactor coil and second parameter information about the support system; establishing a beam unit model about the support system according to the second parameter information, and calculating the first lateral displacement stiffness of the beam unit model; calculating the total lateral displacement stiffness of the support system according to the first lateral displacement stiffness; adjusting the total lateral displacement stiffness according to the first parameter information and the second parameter information, and calculating the natural fundamental frequency. The technical solution provided in the embodiment of the present invention obtains parameter information about the reactor coil and the support system, and calculates the total lateral displacement stiffness of the support system based on the information, and outputs the natural fundamental frequency of the reactor equipment by further correcting the coil mass and the total lateral displacement stiffness, thereby ensuring that the structural dynamic characteristics of the reactor equipment are evaluated in the scheme design stage, assisting in guiding the design and selection of the support system, and improving the design and development efficiency.

Description

Technical Field

[0001] The invention relates to a method and a device for predicting the self-oscillation fundamental frequency of a dry-type air-core reactor, belonging to the technical field of reactors. Background Art

[0002] Dry-type air-core reactors have the characteristics of simple structure, good linearity of reactance value, relatively low equipment cost, and convenient installation and maintenance. They are widely used in reactive power compensation, filtering, current limiting, etc., and are important equipment for UHV substations and converter stations. From a structural point of view, dry-type air-core reactors are generally composed of coils (with rain caps) and support systems. The coils are at a considerable height from the ground, and the equipment is "top-heavy". The frequency of such equipment is usually in the range of 0.5Hz~10Hz, which is close to the frequency of seismic waves and wind loads, and is easy to cause resonance. Therefore, the natural fundamental frequency of the equipment is an important indicator of structural design.

[0003] Regarding the natural fundamental frequency of dry-type air-core reactors, the existing public technical methods usually use finite element simulation calculations using three-dimensional structural digital models after the structural design is completed. However, the disadvantage is that it takes a long time and is difficult to support efficient development work in the scheme design stage. Summary of the invention

[0004] Therefore, the purpose of the present invention is to provide a method and device for predicting the natural fundamental frequency of a dry-type air-core reactor, so as to propose a way to evaluate the natural fundamental frequency and improve the design and development efficiency of new reactor products.

[0005] In order to achieve the above object, the present invention provides a method for predicting the natural fundamental frequency of a dry-type air-core reactor, comprising:

[0006] Obtaining first parameter information about the reactor coil and second parameter information about the support system;

[0007] According to the second parameter information, a beam unit model of the support system is established, and the first lateral displacement stiffness of the beam unit model is calculated;

[0008] According to the first lateral stiffness, calculate the total lateral stiffness of the support system;

[0009] According to the first parameter information and the second parameter information, the total lateral stiffness is adjusted and the natural fundamental frequency is calculated.

[0010] Further, the first parameter information includes quality information of the reactor coil;

[0011] The support system includes a plurality of support components, and the second parameter information includes first structural information and first quantity information of the support components and second structural information and second quantity information of parts included in the support components.

[0012] Furthermore, before establishing the beam unit model of the support system, it also includes:

[0013] The beam element model includes flange mounting.

[0014] Furthermore, the first lateral stiffness of the beam element model is calculated, specifically including:

[0015] The deflection equation is derived according to the model of a cantilever beam with concentrated load applied to its end, and the deflection value under the action of unit force is calculated; the deflection value is used as the stiffness value of the first lateral displacement stiffness.

[0016] Further, according to the first lateral stiffness, the total lateral stiffness of the support system is calculated, specifically including:

[0017] Calculate the second lateral stiffness of the supporting component of the supporting system according to the first lateral stiffness;

[0018] The total lateral stiffness is calculated based on the second lateral stiffness.

[0019] Further, multiple first lateral displacement stiffnesses are calculated by equivalent cumulative parallel connection to obtain a second lateral displacement stiffness;

[0020] Multiple second lateral displacement stiffnesses are calculated by equivalent accumulation in series to obtain the total lateral displacement stiffness.

[0021] Further, according to the first parameter information and the second parameter information, the total lateral stiffness is adjusted and the natural fundamental frequency is calculated, specifically including:

[0022] Adjusting the quality conversion coefficient of the quality information in the first parameter information;

[0023] Add tie rings to the support system to obtain the amplification factor of the tie rings on the total lateral stiffness;

[0024] The natural fundamental frequency is calculated according to the first amplification factor, the amplification factor and the total lateral stiffness.

[0025] In a second aspect, the present invention further provides a device for predicting the natural fundamental frequency of a dry-type air-core reactor, applying the prediction method provided in the first aspect, comprising:

[0026] A parameter information acquisition module, used to obtain first parameter information about the reactor coil and second parameter information about the support system;

[0027] A first lateral displacement stiffness calculation module is used to establish a beam unit model of the support system according to the second parameter information, and calculate a first lateral displacement stiffness of the beam unit model;

[0028] The overall stiffness coefficient calculation module is used to calculate the overall lateral stiffness of the support system according to the first lateral stiffness;

[0029] The natural fundamental frequency calculation module is used to adjust the total lateral stiffness and calculate the natural fundamental frequency according to the first parameter information and the second parameter information.

[0030] By adopting the above technical scheme, a method and device for predicting the natural fundamental frequency of a dry-type air-core reactor provided in an embodiment of the present invention obtains parameter information of the reactor coil and the support system, and calculates the total lateral stiffness of the support system based on this information. By further correcting the coil mass and the total lateral stiffness, the natural fundamental frequency of the reactor equipment is output, thereby ensuring that the structural dynamic characteristics of the reactor equipment are evaluated in the scheme design stage, assisting in guiding the design and selection of the support system, and improving the design and development efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A flow chart of a method for predicting the natural fundamental frequency of a dry-type air-core reactor provided by the present invention;

[0032] Figure 2 A flow chart of calculating the first lateral displacement stiffness in a method for predicting the natural fundamental frequency of a dry-type air-core reactor provided by the present invention;

[0033] Figure 3 A flow chart for calculating the total lateral stiffness in a method for predicting the natural fundamental frequency of a dry-type air-core reactor provided by the present invention;

[0034] Figure 4 A flow chart of calculating the natural fundamental frequency in a method for predicting the natural fundamental frequency of a dry-type air-core reactor provided by the present invention;

[0035] Figure 5 A schematic diagram of a beam unit model in a method for predicting the natural fundamental frequency of a dry-type air-core reactor provided by the present invention;

[0036] Figure 6 A schematic diagram of supporting parts in a supporting component in a method for predicting the natural fundamental frequency of a dry-type air-core reactor provided by the present invention;

[0037] Figure 7 A schematic diagram of an assembled structure of a post insulator in a method for predicting the natural fundamental frequency of a dry-type air-core reactor provided by the present invention;

[0038] Figure 8 The present invention provides a schematic structural diagram of a device for predicting the natural fundamental frequency of a dry-type air-core reactor. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below through the accompanying drawings and specific implementation methods. Usually, the method for estimating the natural fundamental frequency in the dry-type air-core reactor is to use a three-dimensional structural digital model to perform finite element simulation calculations after the structural design is completed, but the disadvantage is that it takes a long time and is difficult to support efficient development work in the scheme design stage.

[0040] Embodiment 1

[0041] like Figure 1 As shown, the present invention provides a method for predicting the natural fundamental frequency of a dry-type air-core reactor, comprising:

[0042] S10: Obtaining first parameter information about the reactor coil and second parameter information about the support system; the support system includes a plurality of support components, which are generally arranged in a circumferential array along the installation pitch diameter. The corresponding first parameter information includes the mass information of the reactor coil; the second parameter information includes the first structural information and the first quantity information of the support component and the second structural information and the second quantity information of the parts included in the support component.

[0043] The first structural information includes the rod diameter, height, density and mechanical performance parameters (elastic modulus E, moment of inertia I, etc.) of the post insulator and the steel post, and the thickness, density and mechanical performance parameters (elastic modulus E, moment of inertia I, etc.) of the tie rod ring.

[0044] S20: According to the second parameter information, a beam unit model of the support system is established, and the first lateral displacement stiffness of the beam unit model is calculated; the specific process is as follows: Figure 2 As shown:

[0045] S21: Derived the deflection equation according to the model of cantilever beam with concentrated load on the end, and calculated the deflection value under unit force;

[0046] S22: The deflection value is used as the stiffness value of the first lateral stiffness.

[0047] Identify the parts with slenderness ratio greater than 5 in the support system, model them with beam element model, and calculate the relationship between deflection y and end concentrated load F according to the model of cantilever beam with end concentrated load, as shown in the figure. Figure 5 As shown:

[0048] (1)

[0049] After integrating formula (1) twice, the second relationship is obtained:

[0050] (2)

[0051] Considering that point B does not produce any displacement under the concentrated load, that is to say x = LDepartment, y =0, then we get:

[0052] (3)

[0053] Then the vertical deflection of the member at any point under the concentrated load at end A is:

[0054] (4)

[0055] (5)

[0056] in, is the lateral stiffness of a single beam element, that is, the first lateral stiffness.

[0057] It should be added here that if the beam unit model uses porcelain post insulators, since the two ends of the porcelain post insulators are glued with flanges, the beam unit model also includes flange glue; and when the porcelain post insulator and the flange are connected in different ways such as glue or spring clip connection, the first lateral displacement stiffness needs to be calculated separately:

[0058] If the glue connection method is adopted, the stiffness of the equivalent beam unit is:

[0059] (6)

[0060] in, The outer diameter of the binding part;

[0061] It is the height of porcelain bushing and flange glue assembly;

[0062] It is the gap distance between flange and porcelain bushing.

[0063] If the spring clip connection method is used, the stiffness of the equivalent beam unit is:

[0064] (7)

[0065] in, It is the height from the center of the spring clip connection to the bottom of the flange.

[0066] S30: Calculate the total lateral stiffness of the support system according to the first lateral stiffness; the specific process is as follows Figure 3 As shown, they include:

[0067] S31: Calculate the second lateral stiffness of the support component of the support system according to the first lateral stiffness; the specific calculation method is to calculate multiple first lateral stiffnesses in parallel and cumulatively to obtain the second lateral stiffness;

[0068] S32: According to the second lateral displacement stiffness, the total lateral displacement stiffness is calculated. The specific calculation method is to calculate multiple second lateral displacement stiffnesses in series and equivalently add them together to obtain the total lateral displacement stiffness. Figure 6 As shown, assuming that a support component is assembled from i support parts, and the connection between the support parts is equivalent to parallel connection. Then the calculation method of the second lateral displacement stiffness of the support component is as follows:

[0069] (8)

[0070] in, is the second lateral stiffness of the first supporting member;

[0071] is the total length of the first support member;

[0072] , … respectively corresponding to the first lateral displacement stiffness of each beam element in the first supporting component;

[0073] , … They correspond to the lengths of the beam elements in the first supporting component respectively;

[0074] According to the lateral stiffness value of each support component and the number of support components, the total lateral stiffness value of the support system is calculated. After the stiffness value of the second lateral stiffness of each support component is calculated separately, the total lateral stiffness of the support system is obtained by cumulative calculation, that is:

[0075] (9)

[0076] in, is the total lateral stiffness of the support system, , … Corresponding to the second lateral displacement stiffness of each supporting component respectively.

[0077] S40: According to the first parameter information and the second parameter information, the total lateral stiffness is adjusted and the natural fundamental frequency is calculated. The specific calculation process is as follows: Figure 4 As shown:

[0078] S41: Adjust the mass conversion coefficient of the mass information in the first parameter information; specifically, a rain cap is provided on the top of the reactor coil to prevent the effect of rainwater, thereby amplifying the mass of the overall structure, and converting the mass of the rain cap into the mass of the coil.

[0079] Adjust the mass of the coil and convert the mass of the support system into the coil. The converted mass is M’.

[0080] S42: Add a tie ring to the support system to obtain the amplification factor of the tie ring on the total lateral stiffness; specifically, a tie ring is set between each support component to provide a fixed support for each support component and amplify the total lateral stiffness of the support component. The amplification factor is .

[0081] S43: Calculate the natural fundamental frequency according to the first magnification factor, the magnification factor and the total lateral stiffness. The details are as follows:

[0082] (10)

[0083] (11)

[0084] in, is the magnification factor generated by the reinforcement ring, and its value range is 1~1.1;

[0085] M is the mass of the coil body (including the rain cap);

[0086] K is the overall stiffness coefficient;

[0087] is the mass conversion coefficient, ranging from 1 / 4 to 1 / 3;

[0088] is the mass of each beam element;

[0089] f is the natural fundamental frequency of the reactor.

[0090] Embodiment 2

[0091] Based on the first embodiment, the present invention provides an implementation example of a method for predicting the natural fundamental frequency of a dry-type air-core reactor, such as Figure 7 As shown, specifically including:

[0092] An initial model of the support system of the reactor is established to obtain the deflection information of the initial model; the support system used by the reactor includes 4 support structures, among which a rain cap is set on the top of the coil, and the support structure uses a post insulator that includes two assembled structures, namely: the first layer of post insulators (spring parts) and the second layer of post insulators (spring parts), and also includes the tie bars added between the post insulators; the mass of the rain cap is about 100kg, and the mass of the coil is about 6000kg. The mass of the tie bars is about 1000kg, and the first layer of post insulators and the second layer of post insulators are of the same model and specifications, that is, they are all composite post insulators. The relevant information parameters are shown in the following table:

[0093] Table 1 Composite post insulator parameters

[0094]

[0095] The total stiffness value K is calculated to be 86909.465, and the amplification factor is 5. Mass conversion factor 1 / 3; Substituting into formula (10) we get:

[0096]

[0097] The numerical comparison is made with the fundamental frequency simulation calculation value, and the comparison file obtained is as follows:

[0098] Table 2 Comparison of base frequency simulation value and calculated value

[0099]

[0100] Embodiment 3

[0101] Based on the first and second embodiments, the present invention proposes a device for predicting the natural fundamental frequency of a dry-type air-core reactor. Figure 8 As shown, including:

[0102] A parameter information acquisition module, used to obtain first parameter information about the reactor coil and second parameter information about the support system;

[0103] A first lateral displacement stiffness calculation module is used to establish a beam unit model of the support system according to the second parameter information, and calculate a first lateral displacement stiffness of the beam unit model;

[0104] The overall stiffness coefficient calculation module is used to calculate the overall lateral stiffness of the support system according to the first lateral stiffness;

[0105] The natural fundamental frequency calculation module is used to adjust the total lateral stiffness and calculate the natural fundamental frequency according to the first parameter information and the second parameter information.

[0106] The device for predicting the natural fundamental frequency of a dry-type air-core reactor provided in the embodiment of the present invention adopts the same technical means as the method for predicting the natural fundamental frequency of a dry-type air-core reactor, and achieves the same technical effect, which will not be described in detail here.

Claims

1. A method for predicting the natural fundamental frequency of a dry-type air-core reactor, characterized in that: include: Obtaining first parameter information about the reactor coil and second parameter information about the support system; According to the second parameter information, a beam unit model of the support system is established, and a first lateral displacement stiffness of the beam unit model is calculated; Calculating the total lateral stiffness of the support system according to the first lateral stiffness; According to the first parameter information and the second parameter information, the total lateral stiffness is adjusted to calculate the natural fundamental frequency, specifically including: Adjusting the quality conversion coefficient of the quality information in the first parameter information; Adding a tie rod ring to the support system to obtain a magnification factor of the tie rod ring on the total lateral stiffness; The natural fundamental frequency is obtained by calculation according to the mass conversion factor, the amplification factor and the total lateral stiffness.

2. The method for predicting the natural fundamental frequency of a dry-type air-core reactor according to claim 1, characterized in that: The first parameter information includes quality information of the reactor coil; The support system includes a plurality of support components, and the second parameter information includes first structural information and first quantity information of the support components and second structural information and second quantity information of support parts included in the support components.

3. The method for predicting the natural fundamental frequency of a dry-type air-core reactor according to claim 1, characterized in that: The beam unit model includes a flange assembly.

4. The method for predicting the natural fundamental frequency of a dry-type air-core reactor according to claim 1, characterized in that: The calculating the first lateral stiffness of the beam unit model specifically includes: The deflection equation is derived according to the model of a cantilever beam with concentrated load applied to the end, and the deflection value under the action of unit force is calculated; the deflection value is used as the stiffness value of the first lateral displacement stiffness.

5. The method for predicting the natural fundamental frequency of a dry-type air-core reactor according to claim 4, characterized in that: Calculating the total lateral stiffness of the support system according to the first lateral stiffness specifically includes: Calculating a second lateral stiffness of a support component of the support system according to the first lateral stiffness; The total lateral stiffness is calculated based on the second lateral stiffness.

6. The method for predicting the natural fundamental frequency of a dry-type air-core reactor according to claim 5, characterized in that: Calculating multiple first lateral displacement stiffnesses by equivalent cumulative calculation in parallel to obtain the second lateral displacement stiffness; Multiple second lateral displacement stiffnesses are calculated by equivalent accumulation in series to obtain the total lateral displacement stiffness.

7. A device for predicting the natural fundamental frequency of a dry-type air-core reactor, using the method for predicting the natural fundamental frequency of a dry-type air-core reactor according to any one of claims 1 to 6, characterized in that: include: A parameter information acquisition module, used to obtain first parameter information about the reactor coil and second parameter information about the support system; A first lateral displacement stiffness calculation module, used for establishing a beam unit model of the support system according to the second parameter information, and calculating a first lateral displacement stiffness of the beam unit model; A total stiffness coefficient calculation module, used for calculating the total lateral stiffness of the support system according to the first lateral stiffness; A natural vibration fundamental frequency calculation module is used to adjust the total lateral stiffness and calculate the natural vibration fundamental frequency according to the first parameter information and the second parameter information, specifically including: adjusting a quality conversion coefficient of the quality information in the first parameter information; Adding a tie rod ring to the support system to obtain a magnification factor of the tie rod ring on the total lateral stiffness; The natural fundamental frequency is obtained by calculation according to the mass conversion factor, the amplification factor and the total lateral stiffness.

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