Current transformer

Abstract

The utility model relates to a current transformer which comprises a coil assembly, an epoxy resin casting body, a P1 wiring copper bar and a P2 wiring copper bar, the coil assembly comprises an annular iron core, a coil winding arranged on the annular iron core and a hoisting support, one end of the hoisting support is provided with a supporting piece, the supporting piece is fixed on the coil winding through a ribbon, and the annular iron core is arranged on the annular iron core. One end of the hoisting support is provided with a coil winding, the other end of the hoisting support is provided with a hoisting plate connected with a pouring mold, two hoisting holes are symmetrically formed in the hoisting plate, two copper inserts connected with the pouring mold are arranged at the positions, corresponding to the two hoisting holes, of the hoisting plate, and the coil winding is connected with the P1 wiring copper bar and the P2 wiring copper bar through two primary leads. The coil winding, the annular iron core and the hoisting support are poured into a whole through epoxy resin to form the epoxy resin pouring body. The utility model has the advantages of compact structure, stable and reliable performance, good insulating property, low partial discharge and high production efficiency.

Description

Technical Field

[0001] The utility model specifically relates to a current transformer. Background Art

[0002] At present, current transformers are generally used in power grid lines and switch cabinets as current measurement and protection equipment. Current transformers are composed of a closed iron core and a winding. The structural design of existing current transformers is unreasonable. When the current transformer is cast with epoxy resin, the coil assembly inside the current transformer cannot be fixed, and the spacing between the iron core and the coil cannot be guaranteed, so that the casting thickness of the epoxy resin is uneven, causing the epoxy resin layer to crack easily, so that the insulation performance of the current transformer is poor, resulting in a high partial discharge of the current transformer, and the coil assembly of the current transformer is easy to impact the cured epoxy resin, causing the cured epoxy resin to crack, and the qualified rate of the product is low. Summary of the invention

[0003] The utility model aims to overcome the defects of the prior art and provide a current transformer with compact structure, stable and reliable performance, good insulation performance, low partial discharge and high production efficiency.

[0004] To achieve the above-mentioned purpose, the utility model adopts a current transformer, including a coil assembly, an epoxy resin casting body, a P1 wiring copper bar and a P2 wiring copper bar arranged on the epoxy resin casting body, the coil assembly including an annular iron core, a coil winding arranged on the annular iron core, and a hanging bracket, one end of the hanging bracket has a support sheet, the support sheet is fixed to the coil winding by a cable tie, the other end of the hanging bracket has a hanging plate connected to the casting mold, two hanging holes are symmetrically arranged on the hanging plate, two copper inserts connected to the casting mold are arranged at the corresponding two hanging holes on the hanging plate, the coil winding is connected to the P1 wiring copper bar and the P2 wiring copper bar by two primary leads, the coil winding, the annular iron core, and the hanging bracket are cast into one by epoxy resin to form the epoxy resin casting body.

[0005] The beneficial effects of the above structure are: the hoisting bracket supports and positions the coil winding of the coil assembly, the hoisting bracket can ensure the spacing between the coil winding and the annular core, and the hoisting bracket is fixed to the bottom plate of the casting mold through the hoisting plate, and two copper inserts connected to the bottom plate of the casting mold are symmetrically arranged on the hoisting plate, which can ensure that the connection between the hoisting plate and the casting mold is more firm, the hoisting bracket will not swing, and the coil assembly will not impact the cured epoxy resin, thereby ensuring that the casting thickness of the epoxy resin is more uniform and the cured epoxy resin is not easy to crack. Therefore, the current transformer has the advantages of compact structure, stable and reliable performance, good insulation performance, low partial discharge, and high production efficiency.

[0006] In particular, the support sheet is provided with an arc-shaped groove matched with the coil winding, and the arc-shaped groove is fitted on the outer peripheral wall of the coil winding. The arc-shaped groove of the support sheet is fitted on the outer peripheral wall of the coil winding, thereby ensuring that the support sheet can reliably support the coil winding, avoiding the shaking of the coil winding, and ensuring that the connection between the support sheet and the coil winding is more compact.

[0007] In particular, the P1 copper bar and the P2 copper bar are symmetrically arranged on both sides of the epoxy resin casting body, and two wiring holes are respectively arranged on the P1 copper bar and the P2 copper bar. The P1 copper bar and the P2 copper bar are respectively arranged on both sides of the epoxy resin casting body, thereby increasing the creepage distance between the P1 copper bar and the P2 copper bar, which is beneficial to improving the insulation performance of the current transformer.

[0008] In particular, the epoxy resin casting body is provided with an shed separating the P1 copper busbar and the P2 copper busbar, which can increase the creepage distance between the P1 copper busbar and the P2 copper busbar, and provide better insulation performance.

[0009] In particular, the epoxy resin casting body is provided with a shed group along the length direction, the shed group includes a large shed and a small shed, and the large shed and the small shed are staggered and distributed on the epoxy resin casting body. The shed group is provided on the epoxy resin casting body, which is conducive to increasing the creepage distance of the current transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram of the internal structure of the main view of an embodiment of the utility model.

[0011] Figure 2 It is a schematic diagram of the internal structure of the embodiment of the utility model from the left.

[0012] Figure 3 It is a top view of an embodiment of the utility model.

[0013] Figure 4 This is a left-side structural diagram of the lifting bracket according to an embodiment of the utility model. DETAILED DESCRIPTION

[0014] like Figures 1 to 4As shown, the embodiment of the utility model is a current transformer, including a coil assembly 10, an epoxy resin casting body 20, a P1 connection copper bar 21 and a P2 connection copper bar 22 arranged on the epoxy resin casting body 20, the coil assembly 10 includes a ring-shaped iron core 11, a coil winding 12 arranged on the ring-shaped iron core 11, and a hanging bracket 13, one end of the hanging bracket 13 has a support sheet 131, the support sheet 131 is fixed to the coil winding 12 by a tie 14, and the hanging bracket 13 is also provided with a support sheet 131. One end is provided with a hanging plate 132 connected to the casting mold, and two hanging holes 133 are symmetrically arranged on the hanging plate 132. Two copper inserts 15 connected to the casting mold are arranged at the corresponding positions of the two hanging holes 133 on the hanging plate 132. The coil winding 12 is connected to the P1 connection copper bar 21 and the P2 connection copper bar 22 by two primary leads. The coil winding 12, the annular iron core 11, and the hanging bracket 13 are integrally cast by epoxy resin to form the epoxy resin casting body 20. The support sheet 131 is provided with an arc groove 1311 matching with the coil winding 12, and the arc groove 1311 is attached to the outer peripheral wall of the coil winding 13. The arc groove of the support sheet is attached to the outer peripheral wall of the coil winding, so as to ensure that the support sheet can reliably support the coil winding, avoid the shaking of the coil winding, and ensure that the connection between the support sheet and the coil winding is more compact. The P1 copper bar 21 and the P2 copper bar 22 are symmetrically arranged on both sides of the epoxy resin casting body 20, and two wiring holes 200 are respectively arranged on the P1 copper bar 21 and the P2 copper bar 22. The P1 copper bar and the P2 copper bar are respectively arranged on both sides of the epoxy resin casting body, so that the creepage distance between the P1 copper bar and the P2 copper bar can be increased, which is beneficial to improve the insulation performance of the current transformer. The epoxy resin casting body 20 is provided with an umbrella skirt 201 separated between the P1 copper bar 21 and the P2 copper bar 22. The umbrella skirt can increase the creepage distance between the P1 copper bar and the P2 copper bar, and the insulation performance is better. The epoxy resin casting body 20 is provided with an umbrella skirt group 202 along the length direction, and the umbrella skirt group 202 includes a large umbrella skirt 203 and a small umbrella skirt 204. The large umbrella skirt 203 and the small umbrella skirt 204 are staggered and distributed on the epoxy resin casting body 20. An shed group is arranged on the epoxy resin casting body, which is beneficial to increasing the creepage distance of the current transformer.

[0015] The hoisting bracket supports and positions the coil winding of the coil assembly. The hoisting bracket can ensure the spacing between the coil winding and the annular core, and the hoisting bracket is fixed to the bottom plate of the casting mold through the hoisting plate. Two copper inserts connected to the bottom plate of the casting mold are symmetrically arranged on the hoisting plate to ensure that the connection between the hoisting plate and the casting mold is more secure, the hoisting bracket will not swing, and the coil assembly will not impact the cured epoxy resin, thereby ensuring that the casting thickness of the epoxy resin is more uniform and the cured epoxy resin is not easy to crack. Therefore, the current transformer has the advantages of compact structure, stable and reliable performance, good insulation performance, low partial discharge, and high production efficiency.

Claims

1. A current transformer, comprising a coil assembly, an epoxy resin casting body, a P1 copper busbar and a P2 copper busbar disposed on the epoxy resin casting body, characterized in that: The coil assembly includes an annular iron core, a coil winding arranged on the annular iron core, and a hanging bracket. One end of the hanging bracket has a support plate, and the support plate is fixed to the coil winding by a cable tie. The other end of the hanging bracket has a hanging plate connected to the casting mold. Two hanging holes are symmetrically arranged on the hanging plate, and two copper inserts connected to the casting mold are arranged at the corresponding two hanging holes on the hanging plate. The coil winding is connected to the P1 wiring copper bar and the P2 wiring copper bar by two primary leads. The coil winding, annular iron core, and hanging bracket are cast into one by epoxy resin to form the epoxy resin casting body.

2. The current transformer according to claim 1, characterized in that: The support sheet is provided with an arc-shaped groove matched with the coil winding, and the arc-shaped groove is fitted on the outer peripheral wall of the coil winding.

3. The current transformer according to claim 1 or 2, characterized in that: The P1 copper busbar and the P2 copper busbar are symmetrically arranged on both sides of the epoxy resin casting body, and two wiring holes are respectively arranged on the P1 copper busbar and the P2 copper busbar.

4. The current transformer according to claim 3, characterized in that: The epoxy resin casting body is provided with an umbrella skirt separating the P1 wiring copper bar and the P2 wiring copper bar.

5. The current transformer according to claim 1 or 2, characterized in that: An umbrella skirt group is arranged on the epoxy resin casting body along the length direction. The umbrella skirt group includes a large umbrella skirt and a small umbrella skirt. The large umbrella skirt and the small umbrella skirt are staggered and distributed on the epoxy resin casting body.

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