CN203134546U

CN203134546U - Improved balance characteristic type residual current transformer

Info

Publication number: CN203134546U
Application number: CN 201320125552
Authority: CN
Inventors: 李乾伟; 董勇
Original assignee: HANGZHOU QIANLONG WEIYE ELECTRON CO Ltd
Current assignee: HANGZHOU QIANLONG WEIYE ELECTRON CO Ltd
Priority date: 2013-03-19
Filing date: 2013-03-19
Publication date: 2013-08-14
Anticipated expiration: 2023-03-19

Abstract

An improved balance characteristic type residual current transformer comprises an annular iron core (3), a secondary side coil (2) and a magnetic-conductive balance cover (1), wherein the annular iron core is wound by the secondary side coil (2); the annular iron core and the secondary lateral coil are coated with the magnetic-conductive balance cover (1); an opening gap (4) on the magnetic-conductive balance cover is formed on the outer circumference side wall of the magnetic-conductive balance cover (1); and the inner circumference side wall of the magnetic-conductive balance cover (1) is a double-layered intersected joint wall (5). According to the improved balance characteristic type residual current transformer, a conventional general current transformer is improved on two sides as follows: on one side, the opening gap (4) is moved from the inner circumference wall to the outer circumference wall of the magnetic-conductive balance cover (1), so that the direct coupling way for a primary side wire and a secondary side wire is eliminated to a certain extent, and the balance characteristics of the current transformer are improved; and on the other side, the inner circumference side wall is improved into the double-layered intersected joint wall (5), so that the direct coupling way is further eliminated, and the balance characteristics of the current transformer are further improved.

Description

Equilibrium response modified form residual current transformer

Technical field

The utility model relates to a kind of current transformer, especially a kind of current transformer of improveing magnetic conduction balance cover structure.

Background technology

Residual current transformer is the current transformer that uses in the alternating current earth leakage protective device; primary side is generally multiple conducting wires and passes annular core with equidirectional; also be wound with second siding ring on the annular core; the input termination AC power of primary side; output termination supply line powers to power consumption equipment; when between supply line or power consumption equipment and the earth, not leaking electricity; though multiple conducting wires flows through load current; because of the vector of each phase current and neutral line current with equal zero; what its whole leads generated an electromagnetic field also equals zero with joint efforts, the non-inductive electromotive force of second siding ring.And between supply line or power consumption equipment and the earth, exist when leaking electricity, its leakage current returns power supply without primary side, the vector of each phase current and neutral line current and be not equal to zero, what its lead generated an electromagnetic field also is not equal to zero with joint efforts, thereby second siding ring generation induced potential, its induced potential size direct proportion is in leakage current.

The geometric position difference of multiple conducting wires in annular core because of primary side, the multiple conducting wires of primary side and the degree of coupling of second siding ring are different, when supply line powers to the load, though the vector of each phase current and neutral line current and when equalling zero, but the electromagnetic field that second siding ring is coupled to is isolated the influence of counterbalance effect quality relation, it is made a concerted effort can be greater than zero, namely us can occur at second siding ring and not wish the induced potential that produces.

Between supply line or power consumption equipment and the earth, there is not electric leakage, the induced potential size degree that second siding ring occurs, we are called the equilibrium response of residual current transformer, at load current one regularly, the induced potential that second siding ring occurs is more little, and the equilibrium response of residual current transformer is more good.

In order to improve the equilibrium response of residual current transformer, take permeability magnetic material to coat the method for second siding ring more, the electromagnetic field magnetic line of force so that even primary side multiple conducting wires produces plays multiple conducting wires and the direct-coupled effect of second siding ring of avoiding primary side simultaneously.Produce the magnet short-cut path situation in order to prevent that permeability magnetic material from coating, must leave opened gap on the permeability magnetic material clad structure.

The method of taking permeability magnetic material to coat second siding ring improves the equilibrium response of residual current transformer, in the prior art, for example patent No. CN201741566 name is called " a kind of radome of zero sequence current mutual inductor " and discloses a kind of structure, it has adopted many schemes that permeability magnetic material is superimposed, this scheme plays a role to the equilibrium response that improves residual current transformer, but has the shortcoming of processing and mounting process complexity.

In the prior art, also have the permeability magnetic material punch forming to make the scheme that shielding coats second siding ring, have processing and the simple advantage of mounting process, but its opened gap is out on the close interior all sides of the primary side conductor spacing that passes annular core, the multiple conducting wires of primary side and second siding ring still have direct-coupled approach, affect the further raising of the equilibrium response ability that improves residual current transformer.

The utility model content

It is to design the current transformer that a kind of equilibrium response obtains improveing that the utility model will be separated inferior technical problem.

Solve this technical problem and adopt following measure scheme: this equilibrium response modified form residual current transformer, by annular core, be wound in the outer second siding ring of annular core and be coated on before annular core and the outer magnetic conduction balance cover of second siding ring form, opened gap on the magnetic conduction balance cover is opened on the excircle sidewall of this cover, and the inner periphery sidewall of this cover is double-deck intersection applying wall.

The beneficial effects of the utility model are: the punch forming of this magnetic conduction balance cover, and be divided into two part punching out, have easy to process and the simple advantage of mounting process.Its opened gap is arranged on the excircle sidewall, evenly the electromagnetic field magnetic line of force that produces of primary side multiple conducting wires, isolate the direct coupling of residual current transformer primary side lead and second siding ring effectively, improved the equilibrium response of residual current transformer, at load current one regularly, reduced the induced potential that second siding ring occurs.

Description of drawings

Fig. 1 is the utility model appearance profile (main looking) figure.

Fig. 2 is the A-A cutaway view of Fig. 1.

Embodiment

The utility model is described in detail below in conjunction with embodiment and with reference to accompanying drawing: referring to accompanying drawing, equilibrium response modified form residual current transformer, by annular core 3, be wound in the outer second siding ring 2 of annular core and be coated on annular core and magnetic conduction balance cover 1 that second siding ring is outer is formed, opened gap 4 on the magnetic conduction balance cover is opened on the excircle sidewall of this cover 1, and the inner periphery sidewall of this cover 1 is double-deck intersection applying wall 5.This improved type electric current transformer has been done the improvement of two aspects to the structure that has general current transformer now, the one, the inner periphery sidewall of opened gap 4 from magnetic conduction balance cover 1 moved on the excircle sidewall, with pass the primary side lead of current transformer and opened gap 4 near change into present away from, eliminate the direct-coupled approach of primary side lead and second siding ring to a certain extent, improved the equilibrium response of residual current transformer; The 2nd, magnetic conduction balance cover 1 inner periphery sidewall is not only arranged opening lock crack, also be improved to double-deck intersection applying wall 5, eliminate the approach of coupling more up hill and dale, through actual measurement, this improvement also has tangible effect to improving equilibrium response.

Claims

1. equilibrium response modified form residual current transformer, by annular core (3), be wound in the outer second siding ring (2) of annular core and be coated on annular core and second siding ring magnetic conduction balance cover (1) is outward formed, it is characterized in that the opened gap (4) on the magnetic conduction balance cover opens on the excircle sidewall of this cover (1), the inner periphery sidewall of this cover (1) is double-deck intersection applying wall (5).