CN115410807A - 550kv cascade electromagnetic voltage transformer - Google Patents

Abstract

The invention relates to a 550kv cascade electromagnetic voltage transformer, which is characterized in that: the expansion device comprises an expander module, an upper insulating submodule, an oil tank module and a lower insulating submodule; the primary coil is divided into two windings which are connected in series and sleeved on the core column of the iron core, and the electric potential of the iron core and the electric potential of the oil tank module are half of that of the iron core; the balance winding is arranged on the iron core, so that magnetomotive forces of two core columns of the iron core are balanced, and the magnetic leakage phenomenon is reduced; in addition, in order to meet the 550kv insulation requirement, a bushing structure with a capacitive screen is designed for voltage sharing, so that the composite requirement of the external insulation distribution of the voltage transformer is ensured.

Description

550kv cascade electromagnetic voltage transformer

Technical Field

The invention relates to the field of cascade voltage transformers, in particular to a 550kv cascade electromagnetic voltage transformer.

Background

The cascade voltage transformer divides all turns of windings into even number of turns of equal stage windings in sequence, and each stage winding is wound on each iron core column respectively by taking one stage in the cascade; connecting the primary windings in series; the secondary winding is only wound on the stage winding to be grounded, so that the leakage flux generated by the load current is large to avoid that the stage windings without the secondary winding are not limited by radial leakage flux, the voltage ratio of the primary winding to the secondary winding is high, a balance winding is wound on each core column of the iron core, and the core columns adjacent to the two iron cores are wound with coupling windings. The cascade structure is used for 110KV and above oil-immersed voltage transformers;

for a 550KV cascade voltage transformer, insulation distribution in common products is disordered, core column magnetomotive force of an iron core cannot be effectively balanced, and a magnetic leakage phenomenon occurs.

Disclosure of Invention

The invention provides a 550KV cascade electromagnetic voltage transformer, which can solve the problems that the general 550KV cascade voltage transformer has disordered insulation distribution, the core column magnetomotive force of an iron core cannot be effectively balanced, and the magnetic leakage phenomenon occurs.

In order to solve the technical problems, the technical scheme of the invention is as follows: the utility model provides a 550kv cascade electromagnetic type voltage transformer which innovation point lies in: the expansion device comprises an expander module, an upper insulating submodule, an oil tank module and a lower insulating submodule;

the expander module comprises an expander, an expander cover and an upper cover plate; the bottom end of the expander is connected to the upper surface of the upper cover plate, the expander is covered by the expander cover, and the bottom end of the expander cover is connected to the upper surface of the upper cover plate; a through hole is formed in the center of the upper cover plate, and a primary conducting bar horizontally extends outwards from the edge of the bottom end of the upper cover plate;

the upper insulator module comprises an upper porcelain bushing, an upper lead pipe and an upper capacitor screen; the upper porcelain bushing is of a cylindrical structure, and umbrella skirts are arranged on the outer contour of the upper porcelain bushing and close to the upper end and the lower end; the top end of the upper porcelain sleeve is connected to the bottom end face of the upper cover plate through a high-pressure flange, and the bottom end of the upper porcelain sleeve is connected to the upper surface of the oil tank module through a high-pressure flange; the upper lead pipe is arranged along the axial direction of the upper porcelain bushing, the top end of the upper lead pipe penetrates through a through hole in the middle of the upper cover plate and extends into the expander, and the bottom end of the upper lead pipe penetrates through the upper porcelain bushing and extends into the oil tank module; the upper capacitive screen is nested outside the upper lead tube and is positioned between the inner wall of the upper porcelain sleeve and the outer wall of the upper lead tube, and the bottom end of the upper capacitive screen extends into the oil tank module;

the lower insulator module comprises a lower porcelain bushing, a lower lead pipe and a lower capacitive screen; the lower porcelain bushing is of a cylindrical structure, and umbrella skirts are arranged below the outer contour of the lower porcelain bushing and close to the upper end and the lower end; the top end of the lower porcelain bushing is connected to the lower surface of the oil tank module through a high-pressure flange, a wire outlet box is arranged at the bottom end of the lower porcelain bushing, and a supporting base is circumferentially arranged on the outer contour of the bottom end of the lower porcelain bushing; the lower lead pipe is arranged along the axial direction of the lower porcelain bushing, the top end of the lower lead pipe extends into the oil tank module, and the bottom end of the lower lead pipe penetrates through the lower porcelain bushing and extends to be connected with the outlet box; the lower capacitive screen is nested outside the lower lead tube and is positioned between the inner wall of the lower porcelain bushing and the outer wall of the lower lead tube, and the top end of the lower capacitive screen extends into the oil tank module;

the oil tank module comprises a tank body, an upper tank cover, a lower tank cover, an iron core, a balance winding, an upper coil, a lower coil and a secondary coil; the box body is of a cylindrical shell structure, the upper box cover and the lower box cover are respectively arranged at the upper end and the lower end of the oil tank module, and through holes for accommodating the lead pipes and the capacitive screen to pass through are formed in the upper box cover and the lower box cover; the iron core is arranged in the box body; the balance winding is provided with a pair of upper balance winding and lower balance winding which are respectively arranged on the iron core; the upper coil is arranged at the bottom end of the upper lead tube and is mutually inducted with the upper balance winding; the lower coil is arranged at the top end of the lower lead tube and is mutually inducted with the lower balance winding; the secondary coil is wound on the outer side of the lower coil and is led out of the lower lead tube to the outlet box.

Furthermore, the upper coil and the lower coil are of single-stage type wrapped coil structures, and full-voltage insulation is adopted between the balance winding and the iron core.

The invention has the advantages that:

1) According to the invention, the primary coil is divided into two windings which are connected in series and sleeved on the core column of the iron core, and the electric potential of the iron core and the electric potential of the oil tank module are one-half; the balance winding is arranged on the iron core, so that magnetomotive forces of two core columns of the iron core are balanced, and the magnetic leakage phenomenon is reduced; in addition, in order to meet the 550kv insulation requirement, a bushing structure with a capacitive screen is designed for voltage sharing, so that the composite requirement of the external insulation distribution of the voltage transformer is ensured.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

Fig. 1 is a schematic structural diagram of a 550kv cascade electromagnetic voltage transformer of the present invention.

Fig. 2 is a schematic circuit diagram of a 550kv cascade electromagnetic voltage transformer of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on orientations or positional relationships shown in the drawings or orientations or positional relationships that the present product is conventionally placed in use, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another, and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical" and the like do not imply that the components are required to be absolutely horizontal or pendant, but rather may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise explicitly stated or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Fig. 1 and 2 show a 550kv cascade electromagnetic voltage transformer, which comprises an expander module 1, an upper insulator module 2, an oil tank module 3 and a lower insulator module 4.

The expander module 1 includes an expander 11, an expander casing 12, and an upper cover plate 13; the bottom end of the expander 11 is connected to the upper surface of the upper cover plate 13, the expander cover 12 covers the expander 11 and the bottom end of the expander cover 12 is connected to the upper surface of the upper cover plate 13; the center of the upper cover plate 13 is provided with a through hole, and the bottom edge of the upper cover plate 13 horizontally extends a primary conductive bar 14 outwards.

The upper insulator module 2 comprises an upper porcelain bushing 21, an upper lead tube 22 and an upper capacitive screen 23; the upper porcelain bushing 21 is in a cylindrical structure, and umbrella skirts are arranged on the outer contour of the upper porcelain bushing 21 and close to the upper end and the lower end; the top end of the upper porcelain bushing 21 is connected to the bottom end face of the upper cover plate 13 through a high-pressure flange, and the bottom end of the upper porcelain bushing 21 is connected to the upper surface of the oil tank module 3 through a high-pressure flange; the upper lead tube 22 is arranged along the axial direction of the upper porcelain bushing 1, the top end of the upper lead tube 22 passes through a through hole in the middle of the upper cover plate 13 and extends into the expander 11, and the bottom end of the upper lead tube 22 passes through the upper porcelain bushing 21 and extends into the oil tank module 3; the upper capacitive screen 23 is nested outside the upper lead tube 22, the upper capacitive screen 23 is positioned between the inner wall of the upper porcelain bushing 21 and the outer wall of the upper lead tube 22, and the bottom end of the upper capacitive screen 23 extends into the oil tank module 3.

The lower insulator module 4 comprises a lower porcelain bushing 41, a lower lead tube 42 and a lower capacitive screen 43; the lower porcelain bushing 41 is in a cylindrical structure, and umbrella skirts are arranged below the outer contour of the lower porcelain bushing 41 and close to the upper end and the lower end; the top end of the lower porcelain bushing 41 is connected to the lower surface of the oil tank module 3 through a high-pressure flange, the bottom end of the lower porcelain bushing 41 is provided with a wire outlet box 5, and the outer contour of the bottom end of the lower porcelain bushing 41 is circumferentially provided with a supporting base 6; the lower lead tube 42 is arranged along the axial direction of the lower porcelain bushing 41, the top end of the lower lead tube 42 extends into the oil tank module 3, and the bottom end of the lower lead tube 42 penetrates through the lower porcelain bushing 41 to extend and be connected with the outlet box 5; the lower capacitive screen 43 is nested outside the lower lead tube 42, the lower capacitive screen 43 is located between the inner wall of the lower porcelain bushing 41 and the outer wall of the lower lead tube 42, and the top end of the lower capacitive screen 43 extends into the oil tank module 3.

The oil tank module 3 comprises a tank body 31, an upper tank cover 32, a lower tank cover 33, an iron core 34, a balance winding 35, an upper coil 36, a lower coil 37 and a secondary coil 38; the box body 31 is a cylindrical shell structure, the upper box cover 32 and the lower box cover 33 are respectively arranged at the upper end and the lower end of the oil tank module 3, and through holes for accommodating lead tubes and the capacitive screen to pass through are formed in the upper box cover 31 and the lower box cover 32; the iron core 34 is arranged in the box body; the balance winding 35 has a pair of upper and lower balance windings, respectively, and is disposed on the iron core 34, respectively; an upper coil 36 is disposed at the bottom end of the upper lead tube 22 and is mutually inductive with the upper balance winding; the lower coil 36 is disposed on the top end of the lower lead tube 42 and is mutually inductive with the lower balance winding; the secondary coil 38 is wound around the outside of the lower coil 37, and the secondary coil 38 is led out of the lower lead tube 42 to an outlet box.

The upper coil 36 and the lower coil 37 both adopt a single-stage wrapped coil structure, and the balance winding 35 and the iron core 34 are all insulated in voltage.

The working principle of the invention is as follows: the primary coil is divided into two windings which are connected in series and sleeved on the core column of the iron core, and the electric potential of the iron core and the electric potential of the oil tank module are half of that of the iron core; the balance winding is arranged on the iron core, so that magnetomotive forces of two core columns of the iron core are balanced, and the magnetic leakage phenomenon is reduced; in addition, in order to meet the 550kv insulation requirement, a bushing structure with a capacitive screen is designed for voltage sharing, so that the external insulation distribution composite requirement of the voltage transformer is ensured.

It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (2)

1. The utility model provides a 550kv cascade electromagnetic voltage transformer which characterized in that: the expansion device comprises an expander module, an upper insulating submodule, an oil tank module and a lower insulating submodule;

the expander module comprises an expander, an expander cover and an upper cover plate; the bottom end of the expander is connected to the upper surface of the upper cover plate, the expander is covered by the expander cover, and the bottom end of the expander cover is connected to the upper surface of the upper cover plate; a through hole is formed in the center of the upper cover plate, and a primary conducting bar horizontally extends outwards from the edge of the bottom end of the upper cover plate;

the upper insulator module comprises an upper porcelain bushing, an upper lead pipe and an upper capacitor screen; the upper porcelain bushing is of a cylindrical structure, and umbrella skirts are arranged on the outer contour of the upper porcelain bushing and close to the upper end and the lower end; the top end of the upper porcelain sleeve is connected to the bottom end face of the upper cover plate through a high-pressure flange, and the bottom end of the upper porcelain sleeve is connected to the upper surface of the oil tank module through the high-pressure flange; the upper lead pipe is arranged along the axial direction of the upper porcelain bushing, the top end of the upper lead pipe penetrates through a through hole in the middle of the upper cover plate and extends into the expander, and the bottom end of the upper lead pipe penetrates through the upper porcelain bushing and extends into the oil tank module; the upper capacitive screen is nested outside the upper lead tube and is positioned between the inner wall of the upper porcelain sleeve and the outer wall of the upper lead tube, and the bottom end of the upper capacitive screen extends into the oil tank module;

the lower insulator module comprises a lower porcelain bushing, a lower lead pipe and a lower capacitive screen; the lower porcelain bushing is of a cylindrical structure, and umbrella skirts are arranged below the outer contour of the lower porcelain bushing and close to the upper end and the lower end; the top end of the lower porcelain bushing is connected to the lower surface of the oil tank module through a high-pressure flange, a wire outlet box is arranged at the bottom end of the lower porcelain bushing, and a supporting base is circumferentially arranged on the outer contour of the bottom end of the lower porcelain bushing; the lower lead tube is arranged along the axial direction of the lower porcelain bushing, the top end of the lower lead tube extends into the oil tank module, and the bottom end of the lower lead tube penetrates through the lower porcelain bushing and extends to be connected with the outlet box; the lower capacitive screen is nested outside the lower lead tube and is positioned between the inner wall of the lower porcelain bushing and the outer wall of the lower lead tube, and the top end of the lower capacitive screen extends into the oil tank module;

the oil tank module comprises a tank body, an upper tank cover, a lower tank cover, an iron core, a balance winding, an upper coil, a lower coil and a secondary coil; the box body is of a cylindrical shell structure, the upper box cover and the lower box cover are respectively arranged at the upper end and the lower end of the oil tank module, and through holes for accommodating the lead pipes and the capacitive screen to pass through are formed in the upper box cover and the lower box cover; the iron core is arranged in the box body; the balance winding is provided with a pair of upper balance winding and lower balance winding which are respectively arranged on the iron core; the upper coil is arranged at the bottom end of the upper lead tube and is mutually inducted with the upper balance winding; the lower coil is arranged at the top end of the lower lead tube and is mutually inducted with the lower balance winding; the secondary coil is wound on the outer side of the lower coil and is led out of the lower lead tube to the outlet box.

2. The 550kv cascade electromagnetic voltage transformer of claim 1, wherein: the upper coil and the lower coil are both in a single-stage type wrapping coil structure, and full-voltage insulation is adopted between the balance winding and the iron core.

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