WO2014102710A1

WO2014102710A1 - A withdrawable circuit breaker with integrated current and voltage transformers

Info

Publication number: WO2014102710A1
Application number: PCT/IB2013/061280
Authority: WO
Inventors: Bhushan KULKARNI; Subbiahthever Dukkaiappan; Hrishikesh S BRAMHAPURIKAR
Original assignee: Abb Technology Ltd
Priority date: 2012-12-28
Filing date: 2013-12-23
Publication date: 2014-07-03
Also published as: CN205212301U

Abstract

A withdrawable circuit breaker with integrated current and voltage transformers. The invention relates to a switchgear comprising a withdrawable circuit breaker (201), a current transformer (205) and a potential transformer (206). The current transformer and potential transformer are mounted on the circuit breaker in an integrated manner, and electrically connected therein with the circuit breaker. The circuit breaker comprises circuit breaker pole having one set of terminals (203) positioned at a perpendicular relationship with the other set of terminals (204).

Description

A SWITCHGEAR

FIELD OF THE INVENTION

The invention relates to a switchgear, and more particularly to a switchgear having fixed circuit breaker.

BACKGROUND

Generally, a switchgear has a circuit breaker, current transformer and potential transformer. In a switchgear having a fixed circuit breaker, the essential components such as circuit breaker, current transformer and potential transformer are mounted separately with suitable reinforcements within the structure of the switchgear, and electrically connected. Such mounting arrangements of the components of the switchgear, in a spaced apart relationship as required increases the length of the electrical conductors. The increase in the length of the electrical conductors eventually increases the current path attributing to increase in voltage loss across the electrical conductors. This affects the performance and efficiency of the switchgear.

The mounting of the components of the switchgear separately with suitable reinforcements, together with the vertical orientation or placement of the circuit breaker poles, increases the size of the switchgear especially along its depth and height.

Therefore there is a need for an invention to provide a switchgear that is compact and have electrical conductors that are comparatively shorter with reduced length.

OBJECTS OF THE INVENTION

It is an object of the invention to provide a switchgear that is compact in size.

It is another object of the invention to provide a switchgear having reduced voltage loss.

It is yet another object of the invention to provide a switchgear that is simple in construction.

Still another object of the invention is to provide a switchgear having improved performance and efficiency and reliability.

SUMMARY OF THE INVENTION Accordingly the present invention relate to a switchgear comprising a circuit breaker, a current transformer and a potential transformer. The current transformer and potential transformer are mounted on the circuit breaker and electrically connected therein with the circuit breaker.

BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the accompanying drawings in which:

Fig. 1 shows a switchgear arrangement in accordance with the prior art;

Fig. 2 shows a switchgear arrangement in accordance with invention; and

Fig. 3 shows the arrangement of the circuit breaker, current transformer and the potential transformer of the switchgear of Fig. 2.

DETAILED DESCRIPTION

In Fig. 1, a switchgear arrangement (100) of the prior art is shown. The switchgear (100) has a circuit breaker (101), current transformer (105) and potential transformer (106) arranged and mounted separately in the switchgear (100). The circuit breaker ( 101) has circuit breaker pole (102) positioned vertically and having terminals (103 and 104). The circuit breaker (101), current transformer (105) and potential transformer (106) are electrically connected herein, with the incoming line connected to the current transformer (105), and the current transformer (105) and potential transformer (106) connected to the terminal (103) of the circuit breaker pole (102) accordingly. The terminal (104) of the circuit breaker pole (102) is connected to the outgoing line.

Here, circuit breaker (101), current transformer (105) and potential transformer (106) are located and positioned separately in the switchgear (100) and mounted accordingly. This requires suitable and / or separate mounting arrangements and the reinforcements accordingly to position them. Also, the length of the electrical connectors connecting the circuit breaker (101), current transformer (105) and potential transformer (106) electrically increases which eventually increases the resistance to the current flow and contribute to the voltage drop thereof. This reduces the performance, efficiency and of the reliability of the switchgear. In Figs. 2 and 3, the switchgear arrangement (200) comprising circuit breaker (201), current transformer (205) and potential transformer (206), in accordance with the invention are shown. The circuit breaker (201), current transformer (205) and potential transformer (206) are mounted and positioned together in an integrated manner. The current transformer (205) is suitably mounted on the top platform of the frame of the circuit breaker (201). Similarly, the potential transformer (206) is also suitably mounted on the bottom platform of the frame of the circuit breaker (201). The required clearance between these electrical components is maintained and or shrouded wherever applicable and required

The incoming line is connected to the current transformer (205), and from the current transformer (205) to one set of terminals (203) of the circuit breaker pole (202) of the circuit breaker (201). The other set of terminals (204) of the circuit breaker pole (202) of the circuit breaker (201) is connected to the outgoing line. The one set of terminals (203) and the other set of terminals (204) are disposed at a perpendicular relationship to each other. The one set of terminals (203) facing upward, whilst it is possible to alter the orientation of the one set of terminals to face downward and maintaining its perpendicular relationship with the other set of terminals (204). The extended set of terminals which is tapped from one set of terminals (203) through the circuit breaker pole (202 and is connected to the potential transformer (206) for sensing the line voltage of the incoming side of the switchgear.

Since, the circuit breaker (201), current transformer (205) and potential transformer (206) are positioned and mounted together in an integrated manner, the length of the electrical connectors employed for establishing electrical connection therein is reduced. This reduces the voltage drop and improves the reliability and performance of the switchgear.

Only certain features of the invention have been specifically illustrated and described herein, and many modifications and changes will occur to those skilled in the art. The invention is not restricted by the preferred embodiment described herein in the description. It is to be noted that the invention is explained by way of exemplary embodiment and is neither exhaustive nor limiting. Certain aspects of the invention that not been elaborated herein in the description are well understood by one skilled in the art. Also, the terms relating to singular form used herein in the description also include its plurality and vice versa, wherever applicable. Any relevant modification or variation, which is not described specifically in the specification are in fact to be construed of being well within the scope of the invention. The appended claims are intended to cover all such modifications and changes which fall within the spirit of the invention.

Thus, it will be appreciated by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricted. The scope of the invention is indicated by the appended claims rather than the foregoing description and all changes that come within the meaning and range and equivalence thereof are intended to be embraced therein.

Claims

WE CLAIM:

1. A switchgear comprising a circuit breaker, a current transformer and a potential transformer, wherein the said current transformer and potential transformer mounted on the said circuit breaker and electrically connected therein with the said circuit breaker.

2. The switchgear as claimed in claim 1 , wherein the said circuit breaker has a frame mounting the said current transformer positioned thereupon the said frame.

3. The switchgear as claimed in claim 1, wherein the said circuit breaker has a frame mounting the said potential transformer positioned thereupon the said frame.

4. The switchgear as claimed in claim 1, wherein the said circuit breaker has circuit breaker poles positioned horizontally.

5. The switchgear as claimed in claim 4, wherein the said circuit breaker poles has one set of terminals electrically connected to the said current transformer.

6. The switchgear as claimed in claim 4, wherein the said circuit breaker poles has other set of terminals electrically connected to the outgoing terminals of the said switchgear.

7. The switchgear as claimed in claims 5 and 6, wherein the said one set of terminals are disposed at a perpendicular relationship with the said other set of terminals.

8. The switchgear as claimed in claims 5 or 7, wherein the said one set of terminals has a interchangeable orientation of perpendicular relationship with the said other set of terminals.

9. The switchgear as claimed in claim 2, wherein the said frame has a plurality of wheels provided for the movement of the said circuit breaker, and the said current transformer and potential transformer mounted thereof.