CN204215892U - A kind of extraordinary current transformer - Google Patents

Abstract

The utility model discloses a special current transformer, which comprises a housing, in which a ring-shaped iron core is arranged, a primary coil is wound on the ring-shaped iron core, an upward-facing primary connecting rod is arranged on the upper end of the housing, and the primary connecting rod passes through the The wire is connected to the primary coil, and the upper end of the shell is provided with a heat conduction hole penetrating the shell from top to bottom, and a heat dissipation device is embedded in the inner surface of the heat conduction hole. The hot end of the sheet is pasted on the copper-aluminum and heat pipe-embedded heat sink, and the cold end of the thermoelectric cooling sheet is pasted on the primary coil. The outer wall of the primary wiring rod is sequentially provided with annular cooling discs with large and small intervals from top to bottom, and the annular cooling discs are gradually thickened from the edge to the end. Several layers of insulating sheds are arranged on the bottom of the housing. The special current transformer of the utility model has a novel structural design, can quickly dissipate the heat generated in the casing to the surrounding environment, and prolong the service life.

Description

A special current transformer

technical field

The utility model relates to the technical field of high-voltage electrical equipment, and relates to a current transformer, in particular to a special current transformer.

Background technique

The principle of current transformer is based on the principle of electromagnetic induction, and the current transformer is composed of closed iron core and winding. When the power system fails, the current transformer is subjected to the thermal effect and electromotive force of the huge current caused by the short-circuit current. The current transformer should have the ability to withstand without being damaged. This ability to withstand is expressed by thermal stability and dynamic stability multiples. . The thermal stability multiple refers to the ratio of the current that does not cause the heat of the current transformer to exceed the allowable limit within 1s of the thermal stability current to the rated current of the current transformer. The dynamic stability multiple is the ratio of the maximum current instantaneous value that a current transformer can withstand to its rated current.

During normal work, there will be a certain amount of heat that needs to be dissipated to the surrounding environment in time; when a power failure occurs, the huge heat generated is the same, and most current transformers cannot achieve the effect of heat dissipation. Therefore, it is necessary to design a current transformer with efficient heat dissipation device.

In the complete set of switchgear for power transmission and distribution, the cabinet body and interlocking mechanism basically adopt the existing relatively mature scheme, and the key is to solve the insulation problem. The insulation distance of the busbar in the cabinet is a key factor affecting product quality and safety. A small insulation distance will easily lead to breakdown and discharge, which will make the technical performance of the entire switchgear product low, and the test cannot meet the requirements of the domestic operating environment and standards. Moreover, the heat dissipation is not good, and the temperature rises, which in turn will lead to insulation damage of the current transformer. In severe cases, it may cause an explosion and cause a safety accident.

Contents of the invention

The utility model aims at the deficiencies of the prior art, and provides a special current transformer. The special current transformer has a novel structural design, can quickly dissipate the heat generated in the casing to the surrounding environment, and prolong the service life.

In order to solve the above-mentioned technical problems, the utility model is solved by the following technical solutions: a special current transformer, including a housing, the housing is provided with an annular iron core, and a primary coil is wound on the annular iron core, The upper end of the housing is provided with an upward primary connecting rod, and the primary connecting rod is connected to the primary coil through a wire, and the inside of the housing and the outside of the primary connecting rod are provided with epoxy resin insulation composed of one-time filling. layer, the upper end of the housing is provided with a heat conduction hole penetrating the housing from top to bottom, and a heat dissipation device is embedded in the inner surface of the heat conduction hole, and the heat dissipation device includes a thermoelectric cooling sheet and copper and aluminum that are fitted with heat pipes to dissipate heat The hot end surface of the thermoelectric cooling sheet is attached to the copper-aluminum and heat pipe-embedded cooling sheet, and the cold end surface of the thermoelectric cooling sheet is attached to the primary coil.

In the above technical solution, preferably, the outer wall of the primary terminal rod is sequentially provided with annular cooling discs at intervals from top to bottom, and the annular cooling discs are gradually thickened from the edge to the end. Beneficial effects: by designing a reasonable heat dissipation structure on the casing, it can ensure that the heat generated during normal use and power failure can be dissipated to the surrounding environment in time.

In the above technical solution, preferably, several layers of insulating sheds are arranged on the bottom of the housing. Beneficial effect: the several layers of insulator sheds arranged in this way can ensure sufficient creepage distance.

Compared with the prior art, the utility model has the following beneficial effects: the special current transformer of the utility model has a novel structural design, and by designing a reasonable heat dissipation structure on the housing, it can ensure The heat generated is dissipated to the surrounding environment in time, which can ensure sufficient creepage distance and prolong the service life.

Description of drawings

Fig. 1 is a schematic structural view of an embodiment of the utility model.

Detailed ways

The utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments: Referring to Figure 1, a special current transformer includes a housing 1, and an annular iron core 2 is arranged inside the housing 1, and the annular iron core 2 is wound with a primary coil 3, the upper end of the housing 1 is provided with an upward primary terminal rod 4, the primary terminal rod 4 is connected to the primary coil 3 through a wire, and the housing 1 is connected to the The primary connecting rod 4 is provided with an epoxy resin insulation layer 6 made of one-time filling. The upper end of the housing 1 is provided with a heat conduction hole 5 penetrating the housing 1 from top to bottom. The inner surface of the heat conduction hole 5 is embedded A heat dissipation device is provided, and the heat dissipation device includes a thermoelectric cooling fin 71 and a copper-aluminum and heat pipe-embedded cooling fin 72. The hot end surface of the thermoelectric cooling fin 71 is attached to the copper-aluminum and heat-pipe-embedded cooling fin 72. The cold end surface of the thermoelectric cooling sheet 71 is attached to the primary coil 3 .

The outer wall of the primary terminal rod 4 is sequentially provided with annular cooling discs 8 at different sizes from top to bottom, and the annular cooling discs 8 are gradually thickened from the edge to the end. By designing a reasonable heat dissipation structure on the casing 1, it can ensure that the heat generated during normal use and power failure can be dissipated to the surrounding environment in time.

Several layers of insulating sheds 9 are arranged on the bottom of the housing 1 . Several layers of insulator sheds 9 arranged in this way can ensure sufficient creepage distance.

When in use, the external power supply provides electric energy to the thermoelectric cooling sheet 71, and the hot end surface of the thermoelectric cooling sheet 71 is attached to the copper-aluminum and heat pipe-embedded heat sink 72, and the cold end surface of the thermoelectric cooling sheet 71 is attached to the primary coil 3. Peltier effect, the heat generated by the primary coil 3 is dissipated through the heat conduction hole 5 through the thermoelectric cooling sheet 71 and the copper-aluminum and heat pipe-embedded heat sink 72 .

Compared with the prior art, the utility model has the following beneficial effects: the special current transformer of the utility model has a novel structural design, and by designing a reasonable heat dissipation structure on the housing, it can ensure The heat generated is dissipated to the surrounding environment in time, which can ensure sufficient creepage distance and prolong the service life.

Claims (3)

1. an extraordinary current transformer, comprise housing (1), annular core (2) is provided with in described housing (1), described annular core (2) is wound with primary winding (3), described housing (1) upper end is provided with primary connection bar (4) upward, described primary connection bar (4) is connected with described primary winding (3) by wire, it is characterized in that: in described housing (1) with described primary connection bar (4) peripheral hardware once property fill the epoxy resin insulating layers (6) formed, described housing (1) upper end is provided with the thermal hole (5) running through described housing (1) from top to down, described thermal hole (5) inner surface is embedded with heat abstractor, described heat abstractor comprises thermoelectric module (71) and copper aluminium fin (72) chimeric with heat pipe, the face, hot junction of described thermoelectric module (71) is attached on described copper aluminium fin (72) chimeric with heat pipe, the cold junction face of described thermoelectric module (71) is attached on described primary winding (3).

2. a kind of extraordinary current transformer as claimed in claim 1, is characterized in that: the outer wall of described primary connection bar (4) is provided with the circular radiating dish (8) of size interval from top to bottom successively, and described circular radiating dish (8) is from edge to end progressive additive.

3. a kind of extraordinary current transformer as claimed in claim 2, is characterized in that: described housing (1) bottom is provided with some layers of insulation full skirt (9).