CN-224232481-U - Built-in open-circuit protection module of current transformer

CN224232481UCN 224232481 UCN224232481 UCN 224232481UCN-224232481-U

Abstract

The utility model discloses a built-in open circuit protection module of a current transformer, which comprises a shell, an iron core, an enamelled copper wire, an S1 connecting terminal, an S2 connecting terminal and isolating paper, wherein the iron core is arranged in the shell, the enamelled copper wire is wound outside the iron core, one end of the enamelled copper wire is butted with the S1 connecting terminal, the other end of the enamelled copper wire is butted with the S2 connecting terminal, the isolating paper is arranged between the shell and the iron core, and the current transformer also comprises a piezoresistor Rp which is connected between the S1 connecting terminal and the S2 connecting terminal in parallel, and the piezoresistor Rp is arranged in the shell. According to the utility model, the voltage dependent resistor Rp is connected in parallel between the S1 connecting terminal and the S2 connecting terminal, so that when an external loop of the current transformer is abnormally opened, the output voltage of the current transformer is limited within a safety range, the safety is improved, and a protection effect is achieved.

Inventors

ZHU LIANGYAN
XIA YU
TIAN ZHUANG
LIN JIABAO

Assignees

厦门鑫精胜电气有限公司

Dates

Publication Date: 20260512
Application Date: 20250515

Claims (3)

1. The utility model provides a built-in open circuit protection module of current transformer, includes shell (1), iron core (2), enamelled copper wire (3), S1 connecting terminal (4), S2 connecting terminal (5) and spacer paper (6), iron core (2) have been installed to shell (1) inside, iron core (2) outside winding has enamelled copper wire (3), enamelled copper wire (3) one end butt joint has S1 connecting terminal (4), enamelled copper wire (3) other end butt joint has S2 connecting terminal (5), be equipped with spacer paper (6) between shell (1) and iron core (2); The voltage-sensitive resistor Rp (7) is connected in parallel between the S1 connecting terminal (4) and the S2 connecting terminal (5), and the voltage-sensitive resistor Rp (7) is arranged in the shell (1).
2. The current transformer built-in open circuit protection module according to claim 1, wherein a section of the enamelled copper wire (3) is spirally wound on the left side and the right side of the iron core (2).
3. The built-in open circuit protection module of the current transformer according to claim 1, wherein the left side and the right side of the upper end of the enamelled copper wire (3) are welded with the S1 connecting terminal (4) and the S2 connecting terminal (5) respectively.

Description

Built-in open-circuit protection module of current transformer Technical Field The utility model relates to the technical field of current transformers, in particular to a built-in open-circuit protection module of a current transformer. Background The current transformer is an instrument for converting primary side large current into secondary side small current to measure according to an electromagnetic induction principle, and consists of a closed iron core and windings, wherein the number of turns of the primary side windings is small, and the primary side windings are connected in series in a circuit of current to be measured. At present, when the external loop of the current transformer is normal, the output voltage of the transformer is the product of the secondary current and the external load, the conventional voltage is several volts, and the larger influence cannot be caused, and when the external loop of the current transformer is abnormally opened, the equivalent external load of the current transformer tends to infinity, the output voltage can be risen to hundreds to kilovolts in a violent way, the personal safety is threatened, and the equipment insulation is damaged. Disclosure of utility model The utility model aims to provide a built-in open-circuit protection module of a current transformer so as to solve the problems in the background technology. In order to achieve the purpose, the utility model adopts the following technical scheme that the current transformer built-in open circuit protection module comprises a shell, an iron core, an enamelled copper wire, an S1 connecting terminal, an S2 connecting terminal and isolating paper, wherein the iron core is arranged in the shell, the enamelled copper wire is wound outside the iron core, one end of the enamelled copper wire is abutted to the S1 connecting terminal, the other end of the enamelled copper wire is abutted to the S2 connecting terminal, the isolating paper is arranged between the shell and the iron core, the current transformer further comprises a piezoresistor Rp which is connected between the S1 connecting terminal and the S2 connecting terminal in parallel, and the piezoresistor Rp is arranged in the shell. Preferably, a section of the enamelled copper wire is spirally wound on the left side and the right side of the iron core respectively. Preferably, the left side and the right side of the upper end of the enamelled copper wire are respectively welded with the S1 connecting terminal and the S2 connecting terminal. Compared with the prior art, the utility model has the beneficial effects that: 1. According to the utility model, the voltage dependent resistor Rp is connected in parallel between the S1 connecting terminal and the S2 connecting terminal, so that when an external loop of the current transformer is abnormally opened, the output voltage of the current transformer is limited within a safety range, the safety is improved, and a protection effect is achieved. 2. The piezoresistor Rp can be selected from bipolar voltage-stabilizing diode, bipolar transient voltage-suppressing diode and bipolar gas discharge tube to improve the selectivity diversity. Drawings FIG. 1 is a schematic diagram of the internal structure of a current transformer according to the present utility model; FIG. 2 is a schematic diagram of a combination of a current transformer and a varistor Rp according to the present utility model; FIG. 3 is a schematic diagram of a current transformer with an internal open-circuit protection element according to the present utility model; FIG. 4 is a schematic diagram of the external circuit of the current transformer with the built-in open-circuit protection element according to the present utility model; Fig. 5 is a schematic diagram of an abnormal structure of an external circuit of the current transformer with the built-in open-circuit protection element. In the figure, a shell-1, an iron core-2, an enamelled copper wire-3, an S1 connecting terminal-4, an S2 connecting terminal-5, a piece of isolating paper-6 and a piezoresistor Rp-7 are shown. Detailed Description In order to further explain the technical scheme of the utility model, the following is explained in detail through specific examples. Referring to fig. 1-2, the utility model provides a built-in open circuit protection module of a current transformer, which comprises a shell 1, an iron core 2, an enamelled copper wire 3, an S1 connecting terminal 4, an S2 connecting terminal 5 and a spacer paper 6, wherein the iron core 2 is arranged in the shell 1, the enamelled copper wire 3 is wound around the left side and the right side of the iron core 2, the iron core 2 and the enamelled copper wire 3 form a basic state of the current transformer, the upper end of the left side of the enamelled copper wire 3 is abutted with the S1 connecting terminal 4, the upper end of the right side of the enamelled copper wire 3 is abutted with the S2 connecting termi