CN108736369A - A kind of medium pressure gas insulation looped network bus section cabinet - Google Patents

Abstract

The invention discloses a medium-voltage gas-insulated ring network bus section cabinet, which includes a gas box room, a mechanism room, a bus room, a pressure relief channel, a secondary element room and a bus coupler, and is characterized in that: the gas box room is composed of a switch It is composed of a room and a busbar raising room, with an integrated common box structure. There are circuit breakers and isolating switches in the switch room. There is a partition in the middle of each air chamber, and there is a line window at the lower part of the partition; there are bus joint seats on the upper part of the left and right sides of the air box room, and there is a pressure equalizing cover in the bus joint seat; the front of the air box room is equipped with a busbar room and a mechanism room; There are two pressure relief passages at the bottom of the box chamber; there is a secondary element chamber below the mechanism chamber and the busbar chamber, and a partition between the pressure relief passages. The invention has the advantages of simple structure, safety and reliability, easy operation and low cost. The bus room, the mechanism room and the secondary element room are all arranged in front of the invention, which is beneficial to the maintenance and repair of the equipment after being put into use.

Description

A medium-voltage gas-insulated ring network bus section cabinet

technical field

The invention relates to a medium-voltage switchgear for a distribution network, in particular to a medium-voltage gas-insulated ring network bus segment cabinet.

Background technique

The switching station of the next pole equipment in the substation is generally equipped with two incoming lines, two sections of busbars and multiple feeders. There is a busbar breaking cabinet between the two sections of busbars. The function of the busbar breaking cabinet is to connect and break the two sections of busbars. Under normal circumstances, the two sections of busbars are not connected and disconnected. When one section of the busbar is powered off, the busbar breaking cabinet is put into use to ensure the normal power supply of the outage busbar, thereby greatly improving the reliability of power supply. This kind of power distribution scheme is mostly realized by KYN mid-mounted switchgear, such as publication number CN105429040 A, which includes a busbar room, a circuit breaker room, a cable room and a low-voltage room. The busbar compartment contains two three-position switches with a common bus terminal, namely the segment three-position switch and the feeder three-position switch. The main bus section function and the branch feeder function are respectively realized through the section switch and the feeder switch. The circuit breaker room contains circuit breakers, current transformers and voltage transformers, multiple cable sockets per pole and a lightning arrester socket, and connecting copper bars. However, this kind of switchgear is not suitable for urban network construction and renovation due to its large volume and high cost; and the fully insulated inflatable ring network cabinet has the advantages of flexible power distribution mode, simple combination of functional units, small size and low cost. be widely used. The inflatable ring network cabinet is the most common use in the typical power distribution scheme of outdoor switchgear.

Contents of the invention

In order to realize the connection of two sections of busbars in the power distribution scheme of the opening and closing of the inflatable ring network cabinet, the invention provides a fully insulated inflatable ring network bus section cabinet.

The present invention is realized through the following technical solutions: a medium-voltage gas-insulated ring network bus section cabinet, including an air box room, a mechanism room, a bus room, a pressure relief channel, a secondary element room and a bus coupler. It is characterized in that the air box room is composed of a switch room and a busbar rising room, and has an integrated common box structure. There are circuit breakers and isolating switches in the switch room, and there are busbars and wall bushings in the bus raising room. There is a partition between the two air rooms. The lower part of the partition has line windows; the upper part of the left and right sides of the air box room is equipped with a bus joint seat, and the bus joint seat is equipped with a pressure equalization cover; the front of the air box room is equipped with two parts: There are current transformers and barometers, and the busbar adopts a fully insulated flexible busbar; there are two pressure relief channels at the bottom of the air box room; there is a secondary element room under the mechanism room and the busbar room, and there is a clapboard.

The upper part of the switch room is a circuit breaker, and the middle is a disconnector. The isolating switch adopts a two-station double-break structure, and there is an isolating switch status observation window on the front of the switch room. There is a bus joint seat on the upper side wall of the switch room. The middle of the bus joint seat is a conductive copper piece. The two ends of the bus joint seat are insulating layers with a bowl-shaped structure. There is also a voltage equalizing cover inside the insulating layer inside the gas box. The conductive copper piece in the middle of the joint is connected. The pressure equalizing cover adopts a metal mesh structure. The insulating layer of the bus connector is made of epoxy resin material, which is cured together with the conductive copper parts and the uniform cover through vacuum mixing and automatic pressure gel process. The insulating layer of the bowl-shaped structure is used for the bus joint seat, which increases the electrical insulation distance between phases and ground, and improves electrical safety. The use of the pressure equalizing cover solves the problem of uneven electric field at the connection between the copper bar and the bus connector, and eliminates the potential hazards caused by metal burrs and bolts.

Due to the small size and compact structure of the gas box, in order to solve the problem of mutual interference of the current transformers during installation, the three-phase wall bushings are arranged obliquely downwards, and the current transformers are staggered. The current transformer is fixed on the bracket, and the bracket is welded on the surface of the gas box.

The busbar 1 is connected to the air box room from the left busbar seat of the bus section cabinet through the bus coupler; the air box room is led out of the air box room to the front busbar room through the wire conversion and the wall bushing; the flexible busbar passes through the core-type current transformer , lead into the air box chamber through the wall bushing, connect the isolation switch and circuit breaker in series, and connect the bus bar 2 from the bus joint seat on the right side of the air box through the bus coupler. The current transformer installed on the flexible busbar provides the current data of busbar 1 or busbar 2 for the relay protection device. Bus 1 or bus 2 will not affect the normal bus power supply due to power failure.

The beneficial effects of the present invention are: the present invention provides a convenient connection method for the connection and disconnection of two busbars; the primary high-voltage live parts are all installed inside the sealed air box, so the present invention is not affected by the external ring mirror; the busbar rises The room solves the problem of the standardization of combining cabinets between the gas-insulated ring network bus section cabinet and other cabinet types; the design of the bus room facilitates the installation, maintenance and replacement of current transformers; the bus room, mechanism room and secondary component room are all It is arranged at the front of the present invention, and it is beneficial to the maintenance and repair of the equipment after being put into use.

Description of drawings

Figure 1: Primary system diagram of the power distribution scheme of the switching station.

Figure 2: Front view of the bus section cabinet.

Figure 3: Left view of the bus section cabinet.

Figure 4: Rear view of the bus section cabinet.

Figure 5: Partial enlarged view of the bus coupler.

In the figure: 1. Air box chamber, 1.1. Barometer, 1.2. Wall bushing, 1.3. Isolating switch, 1.4. Circuit breaker, 1.41. Insulation ring for rear outlet, 1.42. Insulation ring for upper outlet, 1.5. Bus connector , 1.51, insulating layer, 1.52, pressure equalizing cover, 1.6, wall bushing, 1.7, pressure relief window, 1.8, drying box, 2, busbar room, 2.1, flexible busbar, 2.2, current transformer, 2.3, bracket, 3. Pressure relief channel, 4. Secondary component room, 4.1. Relay protection device, 4.2. Control button, 5. Mechanism room, 5.1. Observation window, 5.2. Lower door interlock handle, 5.3. Isolation switch operation hole , 6. Bus coupler.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Fig. 1 is the primary system diagram of the power distribution scheme of the switching station. There is one incoming line and multiple feeder lines under the first bus bar and the second bus bar. Disconnect the two busbars. Under normal circumstances, the present invention is disconnected, and the switch of the present invention is put into use when a section of the bus fails to ensure the normal power supply of the power-cut bus, thus greatly improving the reliability of power supply.

The present invention is mainly divided into six parts: an air box chamber 1 , a busbar chamber 2 , a pressure relief channel 3 , a secondary element chamber 4 , a mechanism chamber 5 , and a bus coupler 6 .

Figure 2 is a front view of the bus section cabinet, the upper part is the bus room 2 and the mechanism room 5, and the lower part is the secondary element room. The secondary element room is divided into left and right parts, with a partition in the middle. The secondary element room on the left is equipped with a relay protection device 4.1, and the secondary element room on the right is equipped with a control button 4.2. Mechanism room 5 panel is provided with isolating switch cutter head position observation window 5.1, is positioned at the lower left side of lower door interlocking handle 5.2. One end of the observation window 5.1 is fixed on the air box chamber 1, and the other end passes through the mechanism chamber isolating switch operation hole and is positioned at the top right of the lower door interlocking handle 5.2. The upper part of the mechanism room 5 panel is also provided with a circuit breaker opening operation hole, a closing operation hole, an energy storage operation hole and an energy storage indication hole. The upper left corner of the bus room 2 is provided with a barometer 1.1.

Fig. 3 is the left side view of the bus section cabinet of the present invention, for the convenience of observation, a partial section is made. Fig. 4 is the rear view of the bus section cabinet of the present invention, in order to facilitate observation, the rear plate is removed. It can be seen from Figure 4 and Figure 3 that the air box room 1 is composed of a switch room and a bus riser room, and has an integrated common box structure. There are circuit breakers 1.4 and isolating switches 1.3 in the switch room, and there are A, B, C three-phase busbar and wall bushing 1.2, there is a partition in the middle of the two air chambers, and the lower part of the partition has a line window; the upper part of the left and right sides of the air box room is equipped with a bus joint seat 1.5. The design of the busbar lifting room realizes the standardization of the connection between the busbar sectional cabinet and other cabinets, which facilitates the expansion and improvement of the system. The circuit breaker 1.4 is provided with a rear outgoing line insulating ring 1.41 and an upper outgoing line insulating ring 1.42. The insulating ring 1.41 of the rear outgoing line has a gap in the downward direction, which is convenient for the connection of the feeder and the rear outgoing line end of the circuit breaker. The insulating ring 1.42 of the upper outgoing line has a gap towards the rear direction, which is convenient for the connection of the busbar and the upper outgoing line end. An insulating ring is added to the 1.4 outlet end of the circuit breaker, which increases the insulation distance between phases and improves the electrical safety performance. As shown in Figure 5, the bus joint seat 1.5 is provided with a bowl-shaped insulating layer 1.51, and a pressure equalizing cover 1.52 is provided inside it; The conductive copper pieces are connected. The pressure equalizing cover 1.52 adopts a metal mesh structure, and the mesh size is 1-2 mm. The insulating layer 1.51 of the bus coupling seat 1.5 is made of epoxy resin material, which is solidified together with the conductive copper parts and the uniform cover through vacuum mixing and automatic pressure gel process. The bus joint seat 1.5 adopts a bowl-shaped insulating layer, which increases the electrical insulation distance between phases and to the ground (gas box wall), and improves electrical safety. The use of the pressure equalizing cover 1.52 solves the problem of uneven electric field at the connection between the copper bar and the bus connector, and eliminates the potential harm caused by metal burrs. The gas box is made of 3mm stainless steel plate and processed into a sealed box by laser welding technology.

As shown in Figure 4, the bottom of the two air chambers of the air box chamber 1 is provided with a pressure relief window 1.7 and a drying box 1.8. Pressure relief window 1.7 bottom is pressure relief channel 3. A metal flame-retardant partition is provided between the pressure relief channel 3 and the secondary element chamber 4 . The design of the pressure relief window and the pressure relief channel solves the safety problem when the equipment fails.

As shown in Figure 3, the busbar room 2 is connected to the air box room 1 through a wall bushing 1.2. The busbar room is provided with a flexible busbar 2.1, a current transformer 2.2 and a bracket 2.3. The bracket 2.3 is welded on the outer surface of the air box chamber 1, the current transformer 2.2 is fixed on the bracket 2.3, and the flexible bus bar 2.1 breaks through the current transformer 2.2. As shown in Figures 3 and 4, due to the small volume and compact structure of the air box, in order to solve the problem of mutual interference when the current transformers are installed, the three-phase wall bushings are arranged obliquely downward, and the three-phase current transformers are also obliquely downward Stagger distribution.

The busbar 1 is connected to the air box chamber 1 from the left busbar seat 1.5 of the bus section cabinet through the bus coupler 6; the air box chamber 1 is led out to the front busbar chamber 2 through the wire conversion and the wall bushing 1.2; the flexible busbar 2.1 Pass through the core-type current transformer 2.2, lead back to the gas box room 1 through the wall bushing 1.2, connect the isolating switch 1.3 and the circuit breaker 1.4 in series, connect the bus coupling seat 1.5 on the right side of the gas box through the bus coupling 6 Enter busbar 2. The current transformer 2.2 installed on the flexible bus provides the relay protection device with the current data of bus 1 or bus 2. When bus 1 or bus 2 loses power due to a fault, the isolating switch 1.3 of the bus section cabinet and the circuit breaker 1.4 are closed Upon commissioning, power is restored to the unfaulted segment.

The invention has the advantages of simple structure, safety and reliability, easy operation and low cost. The bus room, the mechanism room and the secondary element room are all arranged in front of the invention, which is beneficial to the maintenance and repair of the equipment after being put into use.

Claims (4)

1. A medium-voltage gas-insulated ring network bus section cabinet, including an air box room (1), a mechanism room (5), a bus room (2), a pressure relief channel, a secondary component room (4) and a bus coupler (6), characterized in that: the air box room (1) is composed of a switch room and a bus lift room, an integrated common box structure, a circuit breaker (1.4) and a disconnector (1.3) in the switch room, and a bus lift room with Bus bar and wall bushing (1.6), there is a partition in the middle of the two air chambers, and the lower part of the partition has a line window; the upper part of the left and right sides of the air box chamber is equipped with bus joints (1.5); the front of the air box chamber (1) is equipped with There are two parts: the busbar room (2) and the mechanism room (5). The busbar room (2) is equipped with a current transformer (2.2), a barometer (1.1), a fully insulated flexible busbar (2.1); an air box room (1) There are two pressure relief passages (3) at the bottom; a secondary element chamber (4) is provided below the mechanism chamber (5) and the busbar chamber (2), and a partition is provided between the pressure relief passages. 2. The medium-voltage gas-insulated ring network bus segment cabinet according to claim 1, characterized in that: the upper part of the switch room is a circuit breaker (1.4), and the middle is a disconnector (1.3); the disconnector (1.3) adopts two-way Two-position double-fracture structure; the front of the switch room has an observation window for the status of the isolating switch. 3. The medium-voltage gas-insulated ring network bus segment cabinet according to claim 2, characterized in that: the circuit breaker (1.4) is provided with a rear outgoing line insulating ring (1.41) and an upper outgoing line insulating ring (1.42); the rear outgoing line insulation ring (1.42) The ring (1.41) has a gap in the downward direction, and the upper outlet insulating ring (1.42) has a gap in the rear direction. 4. The medium-voltage gas-insulated ring network bus section cabinet according to claim 1, characterized in that: the bus joint seat (1.5) is provided with a bowl-shaped insulating layer (1.51), and its interior is provided with a pressure equalizing cover ( 1.52); the middle of the bus coupling seat (1.5) is a conductive copper piece, and the voltage equalizing cover (1.52) is connected with the conductive copper piece in the middle of the bus coupling seat (1.5); the voltage equalizing cover (1.52) adopts a metal mesh structure, and the mesh size is 1-2 mm; the insulating layer (1.51) of the bus joint seat (1.5) is made of epoxy resin material, and is cured together with the conductive copper parts and the uniform cover through vacuum mixing and automatic pressure gel process.