Insulating device and power equipment having the same

Abstract

The application provides an insulation device and a power equipment with the insulation device. The insulation device comprises an insulation part and at least one conductive part located on at least one surface of the insulation part, wherein the at least one surface of the insulation part facing the at least one conductive part is in a concave shape; a longitudinal section of the at least one conductive part comprises a straight line part in the middle and two curve parts extending outward from two ends of the straight line part respectively, wherein the curve parts satisfy the following equation: wherein d is the insulation thickness of the straight line part of the insulation part along the longitudinal section, i is an imaginary unit, the value range of is (-∞, +∞), and the value range of is (0.5π, 0.56π]. The application can effectively solve the electric field distortion problem at the edge and realize the homogenization of the electric field.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power electronics, and in particular to an insulation device and a power device having the same. BACKGROUND

[0002] Power electronic converters are the development direction of future data center and charging pile power supply due to their high efficiency and modularity. The converter system can be composed of multiple modules in cascade, wherein the system input side is a high-voltage alternating current input (such as an input voltage of 10 kV, 13.8 kV or 20 kV), and the system output side is a low-voltage direct current output (such as an output voltage of 1 kV). In the entire system, there are mainly three places involving the isolation of the system voltage level: the first is the inter-phase insulation and the inter-module insulation, which is mainly realized by the insulation shell of each module; the second is the isolation between the high-voltage side of the auxiliary power supply circuit and the safety extra low voltage (SELV, Safety Extra Low Voltage), and the current main method is to realize a high safety isolation level by adopting two-stage magnetic ring series connection; the third is the insulation between the high-voltage side and the low-voltage side of the main transformer, because the power of the main transformer is high, so the design needs to achieve good heat dissipation conditions at the same time.

[0003] For the insulation between the high-voltage side and the low-voltage side of the main transformer, because the breakdown field strength of air is low, so when air is used as the insulation medium, the size of the transformer is generally large. The insulating oil is flammable and explosive, and after leakage, it is easy to pollute the environment. Therefore, at present, some main transformers use solid as the insulation medium, so that the volume can be reduced while the reliability is improved. Figure 1 As shown in FIG. 1, it is a structural schematic diagram of the existing main transformer 100', wherein the primary side (including the primary side magnetic core 10' and the primary side coil 30') and the secondary side (including the secondary side magnetic core 20' and the secondary side coil 40') of the transformer are respectively located on the upper and lower sides of the insulation structure 50' of the transformer, and are respectively at two different potentials, and they are isolated by the insulation structure 50'. The insulation structure 50' can be a structure of a solid insulation partition plate and a semiconductive layer coated on both sides of the solid insulation partition plate as a shielding layer 51', and such parallel shielding layer structure can confine the electric field in the solid insulation partition plate, fully utilize the high breakdown field strength characteristic of the solid insulation partition plate, realize the decoupling of insulation and magnetism, open the power limit, benefit heat dissipation, and at the same time benefit the electric field homogenization. However, there is obvious electric field distortion at the edge of the solid insulation partition plate of the insulation structure 50', and therefore, the insulation design at the edge is the key to realize the electric field homogenization.

[0004] Meanwhile, for the medium voltage driving circuit, although its size is small, the isolation voltage is increasing with the power device voltage level. A practical example is an isolation transformer for high voltage device driving, whose size is only a few millimeters, and the insulation withstand voltage is as high as 20kV. The magnetic core of such an isolation transformer is in an up-down position relationship, and the coil is surrounded by the magnetic core, and the opposite two planes of the magnetic core are parallel to each other. The middle part of the parallel plane of the magnetic core is a uniform electric field, but the edge of the magnetic core also faces the problem of electric field distortion, and the electric field distortion will reduce the service life of the insulation, so reasonable insulation structure design is very important to the uniformization of the edge electric field, and even to the reduction of the overall size of the transformer.

[0005] Therefore, under the trend of continuously increasing voltage application level, in order to effectively isolate the high and low voltage components, it is necessary to design an insulation structure with high reliability, that is, to require the electric field in the insulation structure to be as uniform as possible. At the same time, in order to improve the power density, it is required to minimize the geometric size of the insulation structure, which also requires reasonable insulation design, especially edge design. SUMMARY

[0006] The purpose of the present application is to provide an insulation device and a power device with the insulation device, which can effectively solve at least one or more defects of the prior art through reasonable edge design.

[0007] In order to achieve the above-mentioned purpose, according to an embodiment of the present application, the present application provides an insulation device, comprising an insulation part and at least one conductive part, the at least one conductive part is located on at least one surface of the insulation part, wherein the at least one surface of the insulation part facing the at least one conductive part is a middle concave shape; and a longitudinal section of the at least one conductive part comprises a straight line part located in the middle and two curve parts extending outward from the two ends of the straight line part respectively, wherein the curve part satisfies the following equation:

[0008]

[0009] wherein, d is the insulation thickness of the straight line part of the insulation part along the longitudinal section, i is an imaginary unit, the value range of is (-∞, +∞), the value range of is (0.5π, 0.56π].

[0010] In an embodiment of the present application, the at least one conductive part comprises a first conductive part and a second conductive part arranged oppositely, and the insulation part is arranged between the first conductive part and the second conductive part.

[0011] In an embodiment of the present application, the first surface of the insulating portion facing the first conductive portion and the second surface of the insulating portion facing the second conductive portion are in a middle concave shape.

[0012] In an embodiment of the present application, each of the curve portions is composed of at least two circular arc lines connected to each other, and the vertex of each of the circular arc lines falls within the range of the curve defined by the equation.

[0013] In an embodiment of the present application, the outer end of each of the curve portions further forms an end point circular arc.

[0014] In an embodiment of the present application, the angle of the end point circular arc is not less than 180°, and the vertex of the end point circular arc is located outside the curve defined by the equation.

[0015] In an embodiment of the present application, the curve portion corresponding to the at least one conductive portion is such that the electric field distortion rate of the area where the two ends of the at least one conductive portion are located is less than a set value.

[0016] In an embodiment of the present application, the insulating portion is composed of a solid insulating material, and the at least one conductive portion is composed of a conductive or semi-conductive material.

[0017] In an embodiment of the present application, the insulating device further comprises an outer contour, and the cross section of the outer contour is circular or square.

[0018] In an embodiment of the present application, the outer contour surrounds the at least one conductive portion and the insulating portion; or the outer contour completely covers the at least one conductive portion and the insulating portion.

[0019] According to another embodiment of the present application, the present application further provides an insulating device comprising an insulating portion and at least one conductive portion, the at least one conductive portion being located on at least one surface of the insulating portion, wherein the at least one surface of the insulating portion facing the at least one conductive portion is in a middle concave shape, wherein the at least one surface comprises a middle portion and an edge, and the middle portion extends in an axial direction to form the edge; and a longitudinal section of the at least one conductive portion comprises a straight line portion and two curve portions extending outwardly from the two ends of the straight line portion respectively; wherein the longitudinal section of the middle portion corresponds to the straight line portion, and the longitudinal section of the edge corresponds to the curve portion.

[0020] In another embodiment of the present application, the curve portion satisfies the following equation:

[0021]

[0022] wherein, d is the insulation thickness of the straight portion of the insulation portion along the longitudinal section, i is an imaginary unit, the value range of d is (-∞, +∞), the value range of d is (0.5π, 0.56π].

[0023] In another embodiment of the present application, the at least one conductive portion comprises a first conductive portion and a second conductive portion oppositely arranged, and the insulation portion is arranged between the first conductive portion and the second conductive portion.

[0024] In another embodiment of the present application, a first surface of the insulation portion facing the first conductive portion and a second surface of the insulation portion facing the second conductive portion are in a middle concave shape.

[0025] In another embodiment of the present application, each of the curve portions is composed of at least two circular arcs connected with each other, and the vertex of each of the circular arcs falls within the range of the curve defined by the equation.

[0026] In another embodiment of the present application, the outer end of each of the curve portions further forms an end point circular arc.

[0027] In another embodiment of the present application, the angle of the end point circular arc is not less than 180°, and the vertex of the end point circular arc is located outside the curve defined by the equation.

[0028] In another embodiment of the present application, the curve portion corresponding to the at least one conductive portion makes the electric field distortion rate of the area where the two ends of the at least one conductive portion are located less than a set value.

[0029] In another embodiment of the present application, the insulation portion is composed of solid insulation material, and the at least one conductive portion is composed of conductive or semi-conductive material.

[0030] In another embodiment of the present application, the first surface comprises a first middle portion extending along a first axial direction to form a first edge, and the longitudinal section of the first middle portion corresponds to the straight portion of the first conductive portion, and the longitudinal section of the first edge corresponds to the curve portion of the first conductive portion; and the second surface comprises a second middle portion extending along a second axial direction to form a second edge, and the longitudinal section of the second middle portion corresponds to the straight portion of the second conductive portion, and the longitudinal section of the second edge corresponds to the curve portion of the second conductive portion.

[0031] Wherein, the first axial direction is opposite to the second axial direction.

[0032] In another embodiment of the present application, the insulation device further comprises an outer profile, the outer profile has a circular or square cross section.

[0033] In another embodiment of the present application, the outer profile surrounds the at least one conductive portion and the insulation portion; or the outer profile completely covers the at least one conductive portion and the insulation portion.

[0034] According to yet another embodiment of the present application, the present application further provides an electrical device, comprising: the insulation device according to any one of the above embodiments; and at least one electrical structure, arranged corresponding to the at least one conductive portion of the insulation device.

[0035] In yet another embodiment of the present application, the at least one conductive portion of the insulation device comprises a first conductive portion and a second conductive portion, and the at least one electrical structure comprises a high-voltage structure and a low-voltage structure, the high-voltage structure is arranged corresponding to the first conductive portion, and the low-voltage structure is arranged corresponding to the second conductive portion.

[0036] In yet another embodiment of the present application, a potential difference between the high-voltage structure and the low-voltage structure is greater than 1 kV and forms an electric field, and the insulation device is arranged in the electric field.

[0037] In yet another embodiment of the present application, the electrical device is a transformer, and the transformer comprises a first magnetic core, a second magnetic core, a first winding, and a second winding; the first winding is surrounded by the first magnetic core and arranged corresponding to the first conductive portion, and the second winding is surrounded by the second magnetic core and arranged corresponding to the second conductive portion; wherein a top surface of the first magnetic core and a top surface of the second magnetic core are arranged in parallel and opposite to each other, the first conductive portion covers the top surface of the first magnetic core, and the second conductive portion covers the top surface of the second magnetic core.

[0038] According to still another embodiment of the present application, the present application further provides an electrical device, comprising: the insulation device according to another embodiment described above; and at least one electrical structure, arranged corresponding to the at least one conductive portion of the insulation device.

[0039] In still another embodiment of the present application, the at least one conductive portion of the insulation device comprises a first conductive portion and a second conductive portion, and the at least one electrical structure comprises a high-voltage structure and a low-voltage structure, the high-voltage structure is arranged corresponding to the first conductive portion, and the low-voltage structure is arranged corresponding to the second conductive portion.

[0040] In still another embodiment of the present application, a potential difference between the high-voltage structure and the low-voltage structure is greater than 1 kV and forms an electric field, and the insulation device is arranged in the electric field.

[0041] In another embodiment of the present invention, the power equipment is a transformer, and the transformer includes a first magnetic core, a second magnetic core, a first winding, and a second winding; the first winding is surrounded by the first magnetic core and is disposed corresponding to the first conductive portion, the second winding is surrounded by the second magnetic core and is disposed corresponding to the second conductive portion; wherein, the top surface of the first magnetic core and the top surface of the second magnetic core are parallel to each other and disposed opposite to each other, the first conductive portion covers the top surface of the first magnetic core, and the second conductive portion covers the top surface of the second magnetic core.

[0042] This invention effectively solves the problem of electric field distortion at the edge by designing the edge of the insulating device, thereby achieving electric field homogenization.

[0043] The present invention further optimizes the design of the edge of the insulating device so that the curved part of the edge meets certain conditions, thereby achieving the goals of uniform electric field and reducing the volume occupied by the edge at the same time.

[0044] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. Attached Figure Description

[0045] The above and other features and advantages of the present invention will become more apparent from a detailed description of exemplary embodiments thereof with reference to the accompanying drawings.

[0046] Figure 1 This is a schematic diagram of the existing main transformer.

[0047] Figure 2A This is a three-dimensional structural diagram of an insulating device according to a preferred embodiment of the present invention;

[0048] Figure 2B For along Figure 2A A cross-sectional view along the AA direction;

[0049] Figure 3A This is a schematic diagram of the structure of the conductive part of the first preferred embodiment of the insulating device of the present invention, which is a "straight section + rounded edge section".

[0050] Figure 3B For along Figure 3A A schematic diagram of the electric field distortion of the cross section shown;

[0051] Figure 4A This is a schematic diagram of the structure of the conductive portion of the insulating device of the present invention, which has a cross-section of "straight portion + edge Rogowski curve portion";

[0052] Figure 4B For along Figure 4A A schematic diagram of the electric field distortion of the cross section shown;

[0053] Figure 5A Schematic diagram of the cross section of the conductive part of the third preferred embodiment of the insulation device of the present application, which is of the structure of "straight line part + defined curve part";

[0054] Figure 5B Normalized equipotential line diagram formed by parallel electrodes when the insulation thickness of the insulation part of the insulation device of the present application is d;

[0055] Figure 5C Schematic diagram of the variation of the electric field distortion ratio Emax / Eavg and the edge width Δx of the insulation device of the present application with the angle ;

[0056] Figure 6A , Figure 6B , Figure 6C Schematic diagrams of the electric field distribution when the edge is a circular arc with R = 4.5 mm, a Rosser curve, and a defined curve ;

[0057] Figure 7 Schematic diagrams of the electric field distortion along the insulation cross-sectional curves of the edge being a circular arc with R = 4.5 mm, a Rosser curve, and a defined curve ;

[0058] Figure 8 Schematic diagram of the cross section of the conductive part of the fourth preferred embodiment of the insulation device of the present application, which is of the structure of "straight line part + circular arc line combination";

[0059] Figure 9 Schematic diagram of the electric field distribution along the insulation cross-sectional curve of the edge being a circular arc line combination with a defined curve φ = 0.56π;

[0060] Figure 10 Schematic diagram of the cross section of the conductive part of the fifth preferred embodiment of the insulation device of the present application, which is of the structure of "straight line part + defined curve part + end point circular arc";

[0061] Figure 11 Schematic diagram of the cross section of the conductive part of the sixth preferred embodiment of the insulation device of the present application, which is of the structure of "straight line part + circular arc line combination + end point circular arc";

[0062] Figure 12A , Figure 12B Schematic diagrams of the electric field distribution when the edge is a Rosser curve and a "defined curve ";

[0063] Figure 13A Schematic diagram of the three-dimensional structure of the insulation device of another preferred embodiment of the present application;

[0064] Figure 13B For along Figure 13A A cross-sectional view along the CC direction;

[0065] Figure 14A This is a three-dimensional structural diagram of a power equipment according to a preferred embodiment of the present invention;

[0066] Figure 14B For along Figure 14A Cross-sectional view along the BB direction;

[0067] Figure 15 This is a three-dimensional structural diagram of a power device according to another preferred embodiment of the present invention. Detailed Implementation

[0068] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that the invention will be thorough and complete, and the concept of the exemplary embodiments will be fully conveyed to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted.

[0069] In describing the elements / components / etc. described and / or illustrated herein, the terms “a,” “an,” “the,” “the,” and “at least one” are used to indicate the presence of one or more elements / components / etc. The terms “comprising,” “including,” and “having” are used to indicate an open-ended inclusion and to mean that additional elements / components / etc. may exist in addition to those listed. Relative terms, such as “upper” or “lower,” may be used in the embodiments to describe the relative relationship of one component of the icon to another component. It is understood that if the device of the icon is flipped so that it is upside down, the component described as being on the “upper” side will become the component on the “lower” side. Furthermore, the terms “first,” “second,” etc., in the claims are used only as illustrative marks and are not intended to limit the number of objects to which they apply.

[0070] To address the problem of electric field distortion at the edges, such as Figure 2A and Figure 2B As shown, the present invention proposes an insulating device 100, which mainly includes an insulating portion 10 and at least one conductive portion 20, wherein the at least one conductive portion 20 is located corresponding to at least one surface of the insulating portion 10. For example, the insulating portion 10 may include a first surface 11 and a second surface 12 disposed opposite to each other, and the at least one conductive portion 20 may include a first conductive portion 21 and a second conductive portion 22 disposed opposite to each other, wherein the insulating portion 10 is disposed between the first conductive portion 21 and the second conductive portion 22.

[0071] The at least one surface of the insulating portion 10 facing the at least one conductive portion 20 can be a middle-recessed shape, the at least one surface including a middle portion and an edge, and the middle portion extending along an axial direction to form the edge. A longitudinal section of the at least one conductive portion 20 includes a straight portion and two curved portions extending outwardly from two ends of the straight portion, respectively, and a longitudinal section of the middle portion of the at least one surface of the insulating portion 10 corresponds to the straight portion of the at least one conductive portion 20, and a longitudinal section of the edge of the at least one surface of the insulating portion 10 corresponds to the curved portion of the at least one conductive portion 20. The curved portion of the at least one conductive portion of the present application can make the electric field distortion rate of the area where the two ends of the at least one conductive portion are located less than a set value. In the present application, the insulating portion 10 can be composed of solid insulating material, and the at least one conductive portion 20 can be composed of conductive or semi-conductive material.

[0072] In Figure 2A and Figure 2B In the embodiments shown in FIGS. 1-3, the first surface 11 and the second surface 12 of the insulating portion 10 are middle-recessed shapes, for example, bowl shapes. The first surface 11 includes a first middle portion 111 extending along a first axial direction F1 (for example, upward) to form a first edge 112, and a longitudinal section of the first middle portion 111 corresponds to the straight portion 211 of the first conductive portion 21, and a longitudinal section of the first edge 112 corresponds to the curved portion 212 of the first conductive portion 21. The second surface 12 includes a second middle portion 121 extending along a second axial direction F2 (for example, downward) to form a second edge 122, and a longitudinal section of the second middle portion 121 corresponds to the straight portion 221 of the second conductive portion 22, and a longitudinal section of the second edge 122 corresponds to the curved portion 222 of the second conductive portion 22. Wherein the first axial direction F1 is opposite to the second axial direction F2.

[0073] In Figure 2A and Figure 2BIn the shown embodiment, the first surface 11 can further comprise an outer profile portion 113 extending outwardly from the outer end of the first edge 112, which is parallel to the straight portion 111; and the second surface 12 can further comprise an outer profile portion 123 extending outwardly from the outer end of the second edge 122, which is parallel to the straight portion 121. The outer profile portions 113, 123 form the outer profile of the insulation device 100, which can have a circular cross-section, for example. Moreover, the outer profile is around the conductive part 20 and the insulation part 10. Of course, it can be understood that the cross-section of the outer profile of the insulation device 100 can also be designed in other shapes, such as a square shape (as shown in Figure 13A and Figure 13B ).

[0074] In the first embodiment of the present application, the insulation device can realize the electric field homogenization through the conductive part with the insulation structure of "straight portion + edge chamfered circular arc portion", and the partial cross-section structure diagram of the longitudinal cross-section thereof is shown in Figure 3A , and the basic technical features are as follows: (1) the insulation device is composed of the first conductive part and the second conductive part from top to bottom, and the insulation part between the first conductive part and the second conductive part; (2) the cross-section curve of the longitudinal cross-section of the first conductive part and the second conductive part comprises the straight portion in the middle and the chamfered portion (i.e. the curved portion is the chamfered circular arc) at the edge, so as to realize the homogenization of the electric field at the edge; (3) the first conductive part and the second conductive part are tightly combined with the insulation part therebetween, and there is no air gap at the interface. The insulation device of this scheme is simple to process, but the electric field distortion at the edge is still relatively serious. For example, for the insulation device in Figure 3A (insulation thickness d = 4 mm, radius r of edge chamfered portion = 4.5 mm), when the voltage U = 45 kV, the average electric field E avg = 45 kV / 4 mm = 11.25 kV / mm, and the electric field distortion ΔE = E - E avg along the curve shown in Figure 3B is 1.25 kV / mm. As can be seen from Figure 3B , the maximum electric field distortion ΔE max is as high as 1.25 kV / mm, and the increase ratio is ΔE max / E avg = 11%.

[0075] In the second embodiment of the present application, the insulation device can realize the electric field homogenization through the conductive part with the insulation structure of "straight portion + edge logarithmic curve portion", and the partial cross-section structure diagram of the longitudinal cross-section thereof is shown in Figure 4AAs shown in the drawings, the basic technical features are: (1) the insulation device is composed of a first conductive part and a second conductive part from top to bottom, and an insulation part located in the middle of the first conductive part and the second conductive part; (2) the cross-sectional curve of the longitudinal section of the first conductive part and the second conductive part includes a straight line part located in the middle and a Rogowski curve part located at the edge, which realizes the homogenization of the edge electric field, wherein the Rogowski curve can be expressed by the equation are described, a and b are positive real numbers; (3) the first conductive part and the second conductive part are closely combined with the insulation part therebetween, and there is no air gap at the interface. Compared with the first embodiment, under the same insulation structure (insulation thickness d = 4 mm, edge fillet radius r = 4.5 mm) and voltage (U = 45 kV) conditions, the maximum electric field distortion ΔE = E-E avg decreases from 1.25 kV / mm to 0.07 kV / mm. This scheme has a very significant effect on the homogenization of the electric field at the edge, but compared with the scheme of the first embodiment, it still has the following shortcomings: (1) the Rogowski curve trajectory is fixed, although the electric field homogenization effect is obvious, but the edge width Δx (i.e. the width between the end point of the straight line part of the insulation part and the outer end point of the curve part of the edge) is relatively increased. For example, in the above insulation structure, the edge width Δx is increased to 1.7 times of the circular arc, which results in a significant increase in the volume of the insulation structure; (2) the shape of the Rogowski curve requires relatively high process technology. When using numerical control technology to process the self-defined curve shape, the self-defined curve needs to be divided into n segments, and each segment is processed as a straight line segment by default, which requires a large number of segments, increases the complexity of the processing process, and it is difficult to control the accuracy of the processed curve.

[0076] In order to achieve the goals of homogenizing the electric field and reducing the volume occupied by the edge at the same time, the third embodiment of the present application proposes an insulation device, which can realize electric field homogenization through the insulation structure of the conductive part being "straight line part + defined curve part", and the partial cross-sectional structure diagram of the longitudinal section thereof is as shown in Figure 5A As shown in the drawings, the basic technical features are: (1) the insulation device is composed of a first conductive part and a second conductive part, and an insulation part located in the middle of the first conductive part and the second conductive part; (2) the cross-sectional curve of the first conductive part and the second conductive part includes a straight line part located in the middle and two curve parts extending outward from the two ends of the straight line part, respectively; (3) the curve part satisfies the following equation:

[0077]

[0078] wherein, d is the insulation thickness of the straight line part of the insulation part along the longitudinal section, i is an imaginary unit, the value range of is (-∞, +∞), The value range is (0.5π, 0.56π).

[0079] Figure 5B The diagram shows the normalized equipotential profile formed by parallel electrodes when the insulation thickness is d. Each equipotential line can be considered a cross-sectional curve of the insulation structure. The curve coincides with the aforementioned Robowski curve, therefore... The electric field distribution of the curve is the same as that of the Rogowski curve. From Figure 5B It can be seen that, with the angle As the angle increases, the cross-sectional curve contracts to the left, meaning the edge width Δx gradually decreases. For the same height h = d / 4, the edge width Δx of different curves varies with the angle. The pattern of change is as follows Figure 5C As shown by curve L1.

[0080] Figure 5C The electric field distortion rate Emax / Eavg and the edge width Δx as a function of angle are shown. The changing pattern.

[0081] Among them, along different angles The maximum electric field value on the corresponding potential line can be expressed by formula (1):

[0082]

[0083] Among them, with As the value increases, the maximum electric field Emax gradually increases. Since E=U / d is a constant, the electric field distortion rate Emax / Eavg also gradually increases.

[0084] like Figure 5C As shown, the angle can be obtained by combining the following two limiting conditions: (1) the edge width Δx of the insulation is less than the width of the Rogowski curve, and (2) according to insulation design experience, the increment of electric field distortion rate (Emax-Eavg) / Eavg is less than 2% to 6% (2% is taken in this theoretical calculation). The range of values However, it is understandable that the angle may vary depending on different design requirements. The value range can also be other ranges, which is not intended to limit the invention.

[0085] like Figures 6A-6C As shown, it illustrates an arc with an edge of r = 4.5 mm, a Rogowski curve, and a curve angle, respectively. The electric field distribution diagram when defining the curve, and the electric field variation along the curves of the three insulating sections are as follows: Figure 7The specific comparison of the three edges is shown in Table 1. The electric field distribution can be calculated by using the finite element method, and the simulation parameters are: voltage U = 45 kV, insulation thickness d = 4 mm. It can be seen from the figure that the maximum electric field is located at the lower side of the edge, and Δx in the figure represents the edge width.

[0086] Table 1 Comparison of edge width and electric field distortion

[0087]

[0088] The specific comparison of the edge width and the maximum electric field distortion of the three curves is shown in Table 1, and the data of the circular arc with an edge of r = 4.5 mm is taken as the benchmark for comparison. The maximum electric field distortion of the circular arc is 1.25 kV / mm, the Roebel curve is reduced to 0.07 kV / mm, the defining curve is increased to 0.20 kV / mm; the Roebel curve is 6% of the circular arc, the defining curve is 16% of the circular arc. Comparing their edge widths, the Roebel curve is 1.7 times that of the circular arc, and the defining curve is reduced to 1.5 times. It can be seen that, compared with the Roebel curve, the defining curve has an increased electric field distortion, but the edge width is reduced.

[0089] Compared with the insulation device with the curve part of the Roebel curve, if the cross-sectional diameter of the high-frequency high-voltage transformer perpendicular to the insulation thickness direction is 90 mm (the cross-sectional diameter is shown in Figure 1 the insulation device with the curve part of the defining curve of the present application will reduce the diameter by 2.4%; for an auxiliary power transformer with a cross-sectional diameter of 50 mm, the insulation device with the curve part of the defining curve of the present application will reduce the diameter by 4.4%; for future high-frequency and high-voltage device isolation drive applications, due to the reduction of the size of the insulation device itself, the improvement effect of the insulation device with the curve part of the defining curve of the present application will be more obvious (for example, if the cross-sectional diameter of the isolation transformer is 16 mm, the reduction ratio reaches 13.7%).

[0090] Therefore, the insulation device with the curve part of the defining curve of the third embodiment of the present application has the following advantages: (1) compared with the scheme of the first embodiment of the "straight line part + edge rounded corner circular arc part", the scheme of the third embodiment of the present application can reduce the edge electric field distortion, thereby improving the partial discharge level of the equipment and facilitating the insulation thinning design; (2) compared with the scheme of the second embodiment of the "straight line part + edge Roebel curve part", the scheme of the third embodiment of the present application can reduce the insulation edge width and realize electric field homogenization in a compact volume.

[0091] However, the edge curve described by the specific equation in the third embodiment requires a higher processing technology. In order to overcome this shortcoming, the fourth embodiment of the present application proposes an insulation device which can replace the curve defined by the specific equation in the third embodiment with a combination of a series of circular arcs, that is, each curve portion can be composed of at least two circular arcs connected to each other, and the vertex of each circular arc falls within the range of the curve defined by the equation. As shown in Figure 8 , which shows the cross-sectional structure of the insulation device of the fourth embodiment of the present application, the conductive part of which is a "straight line portion + circular arc combination", the basic technical features are: (1) the insulation device is composed of a first conductive part and a second conductive part, and an insulation part located between the first conductive part and the second conductive part; (2) the cross section of the first conductive part and the second conductive part includes a straight line portion located in the middle and two curve portions extending outward from the two ends of the straight line portion, respectively, each of the curve portions is composed of at least two circular arcs connected to each other; (3) the vertex of each circular arc of the circular arc combination of the edge falls within the range of the curve defined by the equation, and the curve satisfies the following equation:

[0092]

[0093] wherein, d is the insulation thickness of the straight line portion of the insulation part along the longitudinal cross section, i is the imaginary unit, the value range of is (-∞, +∞), the value range of is (0.5π, 0.56π].

[0094] As shown in Figure 9 , which shows the electric field distribution diagram of the edge which is a circular arc combination (the vertex of the circular arc falls within the range of the curve defined by ), compared with the edge of the circular arc of r = 4.5 mm of Figure 6A and the Rogowski curve of Figure 6B , the specific comparison of the three edge widths and the maximum electric field distortion is shown in Table 2. Among them, the circular arc combination is composed of six circular arcs connected to each other, and their vertices fall on the curve defined by . The simulation parameters are the same as described above: voltage U = 45 kV, insulation thickness d = 4 mm. The maximum electric field is located at the lower side of the edge, and Δx in the figure represents the edge width.

[0095] Table 2 Comparison of edge width and electric field distortion

[0096]

[0097] The specific comparison of three edge widths and maximum electric field distortion is shown in Table 2, and the data of the edge of the circular arc with r = 4.5 mm is taken as the benchmark for comparison. It can be seen that the electric field distortion of the circular arc line combination is 0.68 kV / mm, which is reduced by 55% compared with the electric field distortion of the circular arc (1.25 kV / mm), which is greater than the electric field distortion of the Rosin curve (0.07 kV / mm). However, the edge width of the circular arc line combination defining the curve is 1.5 times that of the circular arc, which is smaller than the edge width of the Rosin curve (1.7 times). The edge width of the circular arc line combination defining the curve is 1.5 times that of the circular arc, which is smaller than the edge width of the Rosin curve (1.7 times).

[0098] The advantages of the scheme of the fourth embodiment of the present application are: (1) Compared with the scheme of the first embodiment of "straight line part + edge rounded corner circular arc part", the scheme of the fourth embodiment of the present application can reduce the edge electric field distortion, so as to improve the partial discharge level of the equipment and facilitate the insulation thinning design; (2) Compared with the scheme of the second embodiment of "straight line part + edge Rosin curve part", the scheme of the fourth embodiment of the present application can reduce the insulation edge width and realize electric field homogenization in a compact volume; (3) Compared with the scheme of the third embodiment of "straight line part + defined curve part", the edge is replaced by the circular arc line combination defining the curve, which reduces the requirement on the process technology.

[0099] The fifth embodiment of the present application also proposes an insulation device, which realizes electric field homogenization through the "straight line part + defined curve part + endpoint circular arc" insulation structure of the conductive part, as shown in Figure 10 The basic technical features are: in addition to the straight line part in the middle and the two curve parts (the curve parts satisfy the equation definition) extending outward from the two ends of the straight line part, an endpoint circular arc is further formed at the outer end of each curve part. Preferably, the angle of the endpoint circular arc is not less than 180°, and the vertex of the endpoint circular arc is located outside the curve defined by the equation.

[0100] The sixth embodiment of the present application also proposes an insulation device, which realizes electric field homogenization through the "straight line part + circular arc line combination (four circular arc lines) + endpoint circular arc" insulation structure of the conductive part, as shown in Figure 11 The basic technical features are: in addition to the straight line part in the middle and the multiple circular arc line combinations (the vertex of each circular arc line falls within the range of the curve defined by the equation) at the end, an endpoint circular arc is further formed at the outer end. Preferably, the angle of the endpoint circular arc is not less than 180°, and the vertex of the endpoint circular arc is located outside the curve defined by the equation.

[0101] The advantages of setting the "end point arc" are illustrated below by taking the insulation structure of the conductive part of the fifth embodiment as an example, which is "straight line part + defined curve part + end point arc". Table 3 shows the specific comparison of edge width and maximum electric field distortion.

[0102] Table 3 Comparison of edge width and maximum electric field distortion

[0103]

[0104] As shown in Figure 12A and Figure 12B , they respectively show the electric field homogenization effect of the edge being a Rosser curve and a "defined curve of the Rosser curve + end point arc (diameter is the insulation thickness d)". Since there is local electric field enhancement at the curve vertex of the Rosser curve edge, if the electric field at this position is required to be no more than the maximum electric field of the edge, the curve is required to have a certain height. Under the condition of insulation thickness d = 4 mm and applied voltage U = 45 kV, the curve height H = 7.8 mm is required. If the insulation structure is a "defined curve of the Rosser curve + end point arc (diameter is the insulation thickness d)", the height is reduced to H = 4.5 mm, and the reduction ratio is 42.3%. In this embodiment, the edge width and electric field optimization effect are equivalent to those of the "defined curve of the Rosser curve", and the advantage is that the requirement for the height of the insulation edge is reduced, which is beneficial to the ventilation and heat dissipation of the device located outside the conductive part.

[0105] As shown in Figure 13A and Figure 13B , they show the perspective structure of the insulation device 100a of another preferred embodiment of the present application, which is different from the embodiments shown in Figure 2A and Figure 2B in that the outer contour of the insulation device 100a of the present embodiment, as well as the transverse section of the first surface 11 and the second surface 12 of the insulation part 10 facing the conductive part 20, is square, while the embodiments shown in Figure 2A and Figure 2B are circular. In the present embodiment, the outer contour is around the conductive part 20 and the insulation part 10.

[0106] The present application also provides a power device, which can include the insulation device 100 or 100a as described above and at least one power structure, which is arranged corresponding to at least one conductive part 20 of the insulation device 100 or 100a.

[0107] ​​​The at least one conductive part of the insulating device 100 or 100a may include, for example, a first conductive part 21 and a second conductive part 22. The at least one electrical structure may include, for example, a high-voltage structure and a low-voltage structure, wherein the high-voltage structure is provided corresponding to the first conductive part 21, and the low-voltage structure is provided corresponding to the second conductive part 22. The potential difference between the high-voltage structure and the low-voltage structure may be greater than 1kV, forming an electric field, and the insulating device 100 or 100a is disposed in the electric field.

[0108] like Figure 14A and Figure 14B The diagram illustrates a three-dimensional structure of a power device 200 according to a preferred embodiment of the present invention. The power device 200 may be, for example, a transformer, which may include a first magnetic core 31, a second magnetic core 32, a first winding 33, and a second winding 34, among other electrical structures. The first winding 33 is surrounded by the first magnetic core 31 and is disposed corresponding to the first conductive portion 21. The second winding 34 is surrounded by the second magnetic core 33 and is disposed corresponding to the second conductive portion 22. Preferably, the top surfaces of the first magnetic core 31 and the second magnetic core 33 are parallel to each other and disposed opposite to each other. The first conductive portion 21 covers the top surface of the first magnetic core 31 in a longitudinal section, and the second conductive portion 22 covers the top surface of the second magnetic core 32 in a longitudinal section.

[0109] like Figure 15As shown, it shows the perspective structure of the power equipment 200a of another preferred embodiment of the present application. In the present embodiment, the power equipment 200a comprises an insulation device 100b, the insulation part 10 of the insulation device 100b has edges 112, 122, the structure of which can be the same as the edges 112, 122 of the insulation devices 100, 100a described above, which will not be repeated here. The conductive part 20 of the insulation device 100b comprises first conductive parts 21 and 22. The power equipment 200a can be a transformer, for example, and can comprise power structures such as a first magnetic core (e.g. a high-voltage magnetic core) 31, a second magnetic core (e.g. a low-voltage magnetic core) 32, a first winding 33 and a second winding 34. The present embodiment is particularly characterized in that the first conductive part 21 corresponds to a conductive or semi-conductive material coated on the lower top surface of the high-voltage magnetic core, and the second conductive part 22 corresponds to a conductive or semi-conductive material coated on the upper top surface of the low-voltage magnetic core, the structure of which can be the same as the conductive part of the insulation devices 100, 100a described above. Correspondingly, the edges of the lower top surface of the high-voltage magnetic core and the edges of the upper top surface of the low-voltage magnetic core need to meet the edge design described above. The insulation part 10 of the insulation device 100b is made of silicone material and has a square outer contour 50, and the outer contour 50 completely covers the conductive part and the insulation part of the insulation device 100b, and completely covers the power structures such as the first magnetic core 31, the second magnetic core 32, the first winding 33 and the second winding 34.

[0110] The present application can effectively solve the problem of electric field distortion at the edge of the insulation device by designing the edge of the insulation device, and realize the uniformization of the electric field.

[0111] The present application further optimizes the design of the edge of the insulation device, so that the curved part of the edge meets certain conditions, and the goals of uniformizing the electric field and reducing the volume occupied by the edge can be achieved at the same time.

[0112] The exemplary embodiments of the present application are specifically shown and described above. It should be understood that the present application is not limited to the disclosed embodiments, but rather the present application is intended to encompass various modifications and equivalent arrangements within the spirit and scope of the appended claims.

Claims

1. An insulation device comprising an insulation portion and at least one conductive portion, the at least one conductive portion being located on at least one surface of the insulation portion, characterized in that, the at least one surface of the insulation portion facing the at least one conductive portion is concave in the middle; and a longitudinal section of the at least one conductive portion comprises a straight portion in the middle and two curved portions extending outwardly from two ends of the straight portion respectively, wherein the curved portions satisfy the following equation: wherein, d is the insulation thickness of the straight portion of the insulation portion along the longitudinal cross section, i is an imaginary unit, the value range of is (-∞, +∞), the value range of is (0.5π, 0.56π].

2. The insulating device of claim 1, wherein, the at least one conductive portion comprises a first conductive portion and a second conductive portion arranged oppositely, and the insulation portion is arranged between the first conductive portion and the second conductive portion.

3. The insulating device of claim 2, wherein, the first surface of the insulation portion facing the first conductive portion and the second surface of the insulation portion facing the second conductive portion are concave in the middle.

4. The insulating device of claim 1, wherein, each of the curved portions is composed of at least two circular arcs connected with each other, and a vertex of each of the circular arcs falls within a range of the curve defined by the equation.

5. The insulating device of claim 1, wherein, an outer end of each of the curved portions further forms an end-point circular arc.

6. The insulating device of claim 5, wherein, an angle of the end-point circular arc is not less than 180°, and a vertex of the end-point circular arc is located outside the curve defined by the equation.

7. The insulating device according to any one of claims 1-6, characterized in that the corresponding curved portions of the at least one conductive portion make an electric field distortion rate of regions where two ends of the at least one conductive portion are located less than a set value.

8. The insulating device according to any one of claims 1-6, characterized in that the insulation portion is composed of a solid insulation material, and the at least one conductive portion is composed of a conductive or semi-conductive material.

9. The insulating device of claim 1, wherein, the insulation device further comprises an outer contour, and a section of the outer contour is circular or square.

10. The insulating device of claim 9, wherein, the outer contour surrounds the at least one conductive portion and the insulation portion; or the outer contour completely covers the at least one conductive portion and the insulation portion.

11. An insulation device comprising an insulation portion and at least one conductive portion, the at least one conductive portion being located on at least one surface of the insulation portion, characterized in that, the at least one surface of the insulation portion facing the at least one conductive portion is concave in the middle, wherein the at least one surface comprises a middle portion and an edge, and the middle portion extends in an axial direction to form the edge; and a longitudinal section of the at least one conductive portion comprises a straight portion and two curved portions extending outwardly from two ends of the straight portion respectively; wherein a longitudinal section of the middle portion corresponds to the straight portion, and a longitudinal section of the edge corresponds to the curved portions.

12. The insulating device of claim 11, wherein, the curved portions satisfy the following equation: wherein, d is the insulation thickness of the straight portion of the insulation portion along the longitudinal cross section, i is an imaginary unit, the value range of is (-∞, +∞), the value range of is (0.5π, 0.56π].

13. The insulating device of claim 12, wherein, the at least one conductive portion comprises a first conductive portion and a second conductive portion arranged oppositely, and the insulation portion is arranged between the first conductive portion and the second conductive portion.

14. The insulating device of claim 13, wherein, the first surface of the insulation portion facing the first conductive portion and the second surface of the insulation portion facing the second conductive portion are concave in the middle.

15. The insulating device of claim 12, wherein, each of the curved portions is composed of at least two circular arcs connected with each other, and a vertex of each of the circular arcs falls within a range of the curve defined by the equation.

16. The insulating device of claim 12, wherein, an outer end of each of the curved portions further forms an end-point circular arc.

17. The insulating device of claim 16, wherein, an angle of the end-point circular arc is not less than 180°, and a vertex of the end-point circular arc is located outside the curve defined by the equation.

18. The insulating device according to any one of claims 11-17, characterized in that The curve portion corresponding to the at least one conductive part makes the electric field distortion rate of the area where the two ends of the at least one conductive part are located less than a set value.

19. The insulating device according to any of claims 11-17, characterized in that The insulating part is made of solid insulating material, and the at least one conductive part is made of conductive or semi-conductive material.

20. The insulating device of claim 14, wherein, The first surface includes a first middle part extending along a first axial direction to form a first edge, and the longitudinal section of the first middle part corresponds to the straight line portion of the first conductive part, and the longitudinal section of the first edge corresponds to the curve portion of the first conductive part. The second surface includes a second middle part extending along a second axial direction to form a second edge, and the longitudinal section of the second middle part corresponds to the straight line portion of the second conductive part, and the longitudinal section of the second edge corresponds to the curve portion of the second conductive part. The first axial direction is opposite to the second axial direction.

21. The insulating device of claim 11, wherein, The insulating device further includes an outer contour, and the cross section of the outer contour is circular or square.

22. The insulating device of claim 21, wherein, The outer contour surrounds the at least one conductive part and the insulating part; or The outer contour completely covers the at least one conductive part and the insulating part.

23. An electrical power device, characterized by Comprise: The insulating device according to any one of claims 1-10; At least one power structure is arranged corresponding to the at least one conductive part of the insulating device.

24. The power device of claim 23, wherein, The at least one conductive part of the insulating device includes a first conductive part and a second conductive part, and the at least one power structure includes a high-voltage structure and a low-voltage structure, the high-voltage structure is arranged corresponding to the first conductive part, and the low-voltage structure is arranged corresponding to the second conductive part.

25. The power device of claim 24, wherein, The potential difference between the high-voltage structure and the low-voltage structure is greater than 1kV and forms an electric field, and the insulating device is arranged in the electric field.

26. The power device of claim 24 or 25, wherein, The power equipment is a transformer, and the transformer includes a first magnetic core, a second magnetic core, a first winding and a second winding. The first winding is surrounded by the first magnetic core, and is arranged corresponding to the first conductive part, and the second winding is surrounded by the second magnetic core, and is arranged corresponding to the second conductive part. The top surface of the first magnetic core and the top surface of the second magnetic core are arranged opposite to each other and parallel to each other, the first conductive part covers the top surface of the first magnetic core, and the second conductive part covers the top surface of the second magnetic core.

27. An electrical power device, characterized by Comprise: The insulating device according to any one of claims 11-22; At least one power structure is arranged corresponding to the at least one conductive part of the insulating device.

28. The power device of claim 27, wherein, The at least one conductive part of the insulating device includes a first conductive part and a second conductive part, and the at least one power structure includes a high-voltage structure and a low-voltage structure, the high-voltage structure is arranged corresponding to the first conductive part, and the low-voltage structure is arranged corresponding to the second conductive part.

29. The power device of claim 28, wherein, The potential difference between the high-voltage structure and the low-voltage structure is greater than 1kV and forms an electric field, and the insulating device is arranged in the electric field.

30. The power device of claim 28 or 29, wherein, The power equipment is a transformer, and the transformer includes a first magnetic core, a second magnetic core, a first winding and a second winding. The first winding is surrounded by the first magnetic core and corresponds to the first conductive part, and the second winding is surrounded by the second magnetic core and corresponds to the second conductive part; The top surface of the first magnetic core and the top surface of the second magnetic core are arranged in parallel and opposite to each other, the first conductive part covers the top surface of the first magnetic core, and the second conductive part covers the top surface of the second magnetic core.

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