CN2398752Y

CN2398752Y - A. C. switch cubicle

Info

Publication number: CN2398752Y
Application number: CN 99230419
Authority: CN
Inventors: 王川
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-09-07
Filing date: 1999-09-07
Publication date: 2000-09-27
Anticipated expiration: 2009-09-07

Abstract

The utility model relates to an AC switch cabinet. A distribution circuit in the cabinet has the structure that the circuit is led in from a bus row and is led to a lead-out wire of a service cable through a load branch connecting wire and a branch switch. The utility model is characterized in that current mutual inductors CT are connected in series on the load branch connecting wire between the upper end of the branch switch and the bus row, and the current mutual inductors comprise current mutual inductors CTA and CTC which are respectively arranged on an A phase and a C phase. The utility model not only can eliminate failures of short circuits at AB, BC and ABC phases, but also can carry out grounding short-circuit protection to the A and the C phases. The utility model can eliminate unprotected fields of the branch circuit and rapidly eliminate trouble points below the lower end of the branch switch, and simultaneously, the normal running of the other parts of a distribution device can be guaranteed.

Description

The alternating-current switch cabinet

The utility model relates to the high-voltage alternating power distribution equipment.More particularly, be a kind of alternating-current switch cabinet.

In the prior art; as 6-10KV AC distribution device; in the line construction of its power distribution cabinet inside; for showing meter; and realization short-circuit protection; be provided with between the service cable lead-out wire the branch switch K1 except linking to, simultaneously, in A, C two phase lines, current transformer CTA, CTB be set respectively in load branch.But,, therefore,, or on weight, all place it in the bottom of power distribution cabinet traditionally no matter be on volume because the current transformer capacity that is applied under this occasion is bigger.On circuit structure, this current transformer is between branch switch lower end and service cable lead-out wire.A problem that can not be ignored in this circuit structure is that current transformer can only detect the short trouble on relay road thereafter, and occur in before the current transformer to the short trouble of branch switch lower end can not be detected.Thereby, when when the branch switch lower end has an accident, the branch circuit unprotect, when treating that the point of incoming cables master switch cut-offs, fault is longer perdurabgility, and equipment is impaired serious.Moreover, master switch cut-offs to other power distribution cabinet in the same power distribution room also must be quit work.At this situation, be in the utility model patent specification of 98249338.X at application number, the applicant discloses a kind of name and has been called " switching regulator alternating-current switch cabinet is moved at improved interval ".This scheme is to increase the B phase current mutual inductor is set in said structure, promptly " at the vertical current transformer that is installed with of vertical section of the indoor downlead B of the branch phase of main bus bar; two terminations of its lead-out wire are connected with upper static contact with main bus bar respectively ... " is described as the applicant, what the sort circuit structure was mainly considered is the short circuit of AB phase, the short circuit of BC phase, ABC three-phase shortcircuit, does not consider A, C phase ground short circuit.But in the practical application, exist the ground short circuit of A, C phase inevitably.In addition, this scheme needs increase that current transformer is set than prior art.

The purpose of this utility model is to avoid above-mentioned weak point of the prior art, provides a kind of being not only at the short circuit of AB phase, the short circuit of BC phase, the short circuit of ABC phase to carry out failure removal, simultaneously the alternating-current switch cabinet that also can protect A, C phase ground short circuit.This switch cubicle can eliminate the unprotected field of branch circuit protection, fast excise following fault point, branch switch lower end, ensure the normal operation of power distribution equipment other parts simultaneously.

The purpose of this utility model is achieved through the following technical solutions.

The distribution line structure is in the utility model cabinet: introduce from busbar, through load branch's line (A phase, B phase, C phase), branch switch to the service cable lead-out wire.

Design feature of the present utility model is that series connection is set in place on the load branch line between branch switch upper end and the busbar as the current transformer CT of short-circuit signal detection means; Described current transformer CT comprises and is separately positioned on the current transformer CTA summation current transformer CTB that A goes up mutually with C mutually.

Compared with the prior art, the utlity model has following advantage:

1, the utility model can not only carry out failure removal at the short circuit of AB phase, the short circuit of BC phase, the short circuit of ABC phase, also can protect A, C phase ground short circuit simultaneously.

2, the utility model can eliminate the unprotected field of branch circuit protection, fast excise following fault point, branch switch lower end, ensure the normal operation of power distribution equipment other parts simultaneously.

3, the utility model still adopts two current transformers, does not increase the quantity of current transformer.

Fig. 1 is the prior art circuits schematic diagram.

Fig. 2 is the utility model electrical block diagram.

By the following examples, the utility model is described in further detail in conjunction with the accompanying drawings.

Embodiment:

As shown in Figure 2, in the present embodiment, the distribution line structure is in its cabinet: introduce from busbar 1, through load branch's line (A phase, B phase, C phase) 2, branch switch K1 to service cable lead-out wire 3, in the present embodiment, series connection is set in place on the load branch line 2 between branch switch K1 upper end and the busbar 1 as the current transformer CT of short-circuit signal detection means; Described current transformer CT comprises and is separately positioned on the current transformer CTA summation current transformer CTC that A goes up mutually with C mutually.

Because the employing of microcomputerized control technology, in the present embodiment, the capacity of current transformer CTA, CTC can reduce greatly, and the volume and weight of current transformer can reduce greatly, and enforcement of the present utility model is more easy.

Claims

1, a kind of alternating-current switch cabinet, the distribution line structure is in its cabinet: introduce from busbar (1),, it is characterized in that being set in place on the load branch line (2) between branch switch K1 upper end and the busbar (1) to service cable lead-out wire (3) through load branch's line (A phase, B phase, C phase) (2), branch switch K1 as the current transformer CT series connection of short-circuit signal detection means; Described current transformer CT comprises and is separately positioned on the current transformer CTA summation current transformer CTC that A goes up mutually with C mutually.