RU76511U1 - CELL OF COMPLETE DISTRIBUTION DEVICES KRU / TEK-206 - Google Patents

Abstract

The technical solution relates to the field of electrical engineering, namely to high-voltage switchgear (KRU), designed to receive and distribute electrical energy of three-phase alternating current. The technical result is to improve the technical and operational characteristics of the switchgear cell, in terms of ease of maintenance, reliability and safety, as well as to reduce the area occupied by the switchgear, while maintaining all the electrical characteristics of similar cells. According to the claimed technical solution, the switchgear enclosure is divided into five main compartments: two high-voltage compartments, two low-voltage compartments and a busbar compartment. Two high-voltage circuit breakers are placed in the cell housing, each of which is mounted on its withdrawable element, where, in addition to the high-voltage circuit breaker, current transformers and a high-voltage circuit-breaker control unit are located, which makes it possible to inspect, change and repair the main components of the main circuit in conditions that ensure safe operation without disturbances in the normal operation of circuits in adjacent connections of switchgear cells. In the upper and lower parts of each withdrawable element there are contacts of the high-voltage circuit breaker, which, when driving in and out of the withdrawable element into the cell, respectively, are closed or disconnected from the bus and linear fixed contacts. Blinds are provided in the cell, which, when the withdrawable element is rolled out from it, automatically block access to the bus and line contacts that remain energized in order to prevent electric shock to the operating personnel. The busbars inside the cell are separated by insulating partitions. Cable connections can be carried out both from the rear side of the cell, and inside the cell above and below, and stationary grounding conductors installed in the cell for grounding cable connections or busbars are equipped with an accelerated switching mechanism. At the same time, to ensure the safety of maintenance personnel, a number of locks are additionally provided in the cell. 1 ill.

Description

The technical solution relates to the field of electrical engineering, namely to high-voltage switchgear (KRU), designed to receive and distribute electrical energy of three-phase alternating current.

A switchgear cell is known from the existing level of technology (see RU 55513 U1, IPC Н02В 11/00, published on 08/10/2006), in the housing of which two high-voltage circuit breakers are installed on withdrawable elements, which, unlike switchgear cells with one high-voltage circuit breaker, allows save the space occupied by switchgear cells. In this case, the withdrawable elements both in the working and in the control position are inside the high-voltage compartment of the cell, which is closed on the front side of the cell by a door.

The disadvantage of this design of the switchgear cell is the increase in its volume in depth to ensure the necessary magnitude of the main circuit rupture when the withdrawable element is in the control position. It is also difficult to inspect the withdrawable element when it is in the control position and to access the withdrawable element and the internal volume of the cell when the withdrawable element is in the repair position. In addition, the disadvantage of this design is the likelihood of electric shock from the disconnecting contacts when disconnecting the high-voltage switch from them and finding its withdrawable element outside the cell in the repair position.

The technical result, which this technical solution is aimed at, is to improve the technical and operational characteristics of the switchgear cell, in terms of ease of maintenance, reliability and safety, as well as to significantly reduce the area occupied by the switchgear cell, while maintaining all the electrical characteristics of similar cells.

According to the claimed technical solution, the switchgear enclosure is divided into five main compartments: two high-voltage compartments, two low-voltage compartments and a busbar compartment.

Two high-voltage circuit breakers are placed in the cell housing, each of which is mounted on its withdrawable element, where in addition to

The high-voltage circuit breaker houses current transformers and the control unit of the high-voltage circuit breaker. In the upper and lower parts of each withdrawable element there are contacts of the high-voltage circuit breaker, which, when driving in and out of the withdrawable element into the cell, respectively, are closed or disconnected from the bus and linear fixed contacts. The above provides the possibility of respectively connecting or disconnecting the high voltage circuit breaker from busbars and cable connections. Blinds are provided in the cell, which, when the withdrawable element is rolled out from it, automatically block access to the bus and line contacts that remain energized in order to prevent electric shock to the operating personnel. The busbars inside the cell are separated by insulating partitions. Cable connections can be carried out both from the rear side of the cell, and inside the cell above and below, and stationary grounding conductors installed in the cell for grounding cable connections or busbars are equipped with an accelerated switching mechanism.

At the same time, to ensure the safety of maintenance personnel, a number of locks are additionally provided in the cell, which

- they do not allow the withdrawable element to be moved from the operating position to the control position and from the control position to the working position when the high-voltage circuit breaker is on,

- do not allow turning on the high-voltage circuit breaker when the withdrawable element is in the intermediate (between the working and control) position,

- do not allow the withdrawable element to be moved from the control position to the working position with the earthing switch blades turned on,

- do not allow the earthing switch to be turned on when the switch is on,

- do not allow the disconnection of the current circuits on the withdrawable element in the operating position, and

- they do not allow the withdrawable element to be moved from the control position to the working one without an installed and blocked connector (12).

The proposed technical solution is illustrated by the drawing, which shows a General view of the switchgear cell.

The switchgear cell with voltage of 6 and 10 kV is intended for switchgears of alternating three-phase current with a frequency of 50 Hz of systems with neutral or grounded through an arcing reactor, is a one-way service cell and

It is a prefabricated metal structure, the components of which are welded from bent sheet profiles, inside which all the equipment of the circuits of the main and auxiliary circuits is located.

Two high-voltage circuit breakers (2) are located in the switchgear housing on the withdrawable elements (1). As a result, the area occupied by the switchgear cell 10 (6) kV is two times smaller than the area occupied by the cells of the traditional layout with one switch. Another feature of the switchgear cell is that on each withdrawable element (1), in addition to the high-voltage switch (2), current transformers (3), as well as the control unit (11) with the high-voltage switch (1) are located, which simplifies access to them and troubleshooting cell maintenance process. Placing the main components of the main circuit on the withdrawable element (1) makes it possible to inspect, change, and repair under conditions that ensure safe operation without disturbing the normal operation of the circuits in adjacent connections of switchgear cubicles.

The switchgear enclosure consists of five main compartments: two high-voltage (A), busbar compartments (C) and two low-voltage (D). Cable connections (B) can be carried out both at the connection points (7) located on the rear side of the switchgear cell, as well as at the connection points (5) located inside the cell above and below. In the first embodiment, the possibility of convenient and safe maintenance of cable connections from the rear of the cell is achieved. In the second embodiment, the conclusions of the connection points (7) are not installed, the cell can only be serviced from the front side and is installed leaning against the wall. The busbars inside the cell are separated by insulating partitions (10).

In the cell one above the other in each of the high-voltage compartments (A) is located on the withdrawable element (1) of the high-voltage switch (2).

Disconnecting contacts are located in the upper and lower parts of the withdrawable element (1), which, when the withdrawable element (1) is rolled into the cell, closes with bus and linear fixed contacts. When rolling out the withdrawable element (1) with the switch (2) previously disconnected, the detachable contacts are disconnected, while the switch (2) is disconnected from the busbars of the compartment (C) and cable connections (B).

The withdrawable elements (1) of the switchgear cubicle have three positions:

- working, when the withdrawable element (1) is in the cell body, the main circuits are closed,

- control, when the withdrawable element (1) is located in the cell body, the main circuits are open (the creation of a visible break in the main circuit is achieved) and

- repair, when the withdrawable element (1) is located outside the cell body, the main circuits are open, access to live parts of bus and

Line contacts are automatically closed by curtains. This eliminates the possibility of accidental contact with live parts that remain energized, and provides convenient access to the switch (2) and its drive or other equipment installed on the withdrawable element (1).

In the working, control and repair position, the withdrawable element has a locking mechanism. To facilitate the movement of the withdrawable element (1) to the working position, there is a screw mechanism, to the drive (13) of which a removable handle is attached.

The handles of the drives and control apparatuses, metering, measuring and signaling devices are located on the front side of the switchgear cells.

In the switchgear cubicle for grounding cable connections or busbars (9), stationary grounding conductors (6) are installed, the actuators (8) of which are located on the front side of the cell. The earthing switches (6) are equipped with an accelerated switching mechanism to prevent the formation of an arc in case of accidental grounding of live parts under voltage.

To ensure safety, the switchgear cell has a number of locks, including the switchgear cell can be equipped with external connections locks, i.e. in switchgear cubicles with earthing switches, it is possible to install devices that do not allow grounding switches to be switched on when the withdrawable elements are in the operating position or when any switching electrical equipment is in other switchgear cubicles, from which voltage can be supplied to the cell where the ground electrode is located.

In two low-voltage compartments (D) located above the high-voltage compartments (A), retractable elements with protection, control and signaling equipment are placed. At the same time, the controls and visual controls are located on the front panel (14). The design of the low-voltage compartment (D) allows you to install any set of relay protection, as well as microprocessor protection units.

The design of the front panel of the high-voltage circuit breaker together with the design of the switchgear cubicle provides reliable localization of the high-voltage compartment without the use of additional doors.

Busbars are located in a compartment separated from neighboring cells.

In the event of a short circuit inside the switchgear with an open electric arc, the switchgear design provides localization of the effect of an open electric arc within the compartment by using special measures in the switchgear to limit the duration of the arc to a value of not more than 0.2 s. Short circuit current range,

at which shutdown of the arc short circuit for the specified time is provided - from 5 to 20 kA.

The switchgear cells are equipped with pressure relief devices in combination with arc protection sensors and circuits that are blocked from false switchgear trips, for example, by the presence of a short circuit current or voltage drop in the switchgear.

All devices and devices installed in the switchgear cubicles to be earthed are grounded. On the facade of the cell in the lower part there is a grounding bonnet designed to connect elements temporarily to ground to the grounded housing.

The main busbars of the operational supply, control, and signaling circuits pass through the channel of the intercellular connections of the auxiliary circuits. The channel for intercellular connections is a duct (4) located in the upper part of the switchgear cells.

Claims (1)

A switchgear cubicle including a housing consisting of five main compartments (two high-voltage compartments, two low-voltage compartments and a busbar compartment), two high-voltage circuit breakers, each of which is mounted on a withdrawable element, current transformers, cable connections, busbars and grounding conductors, in the upper and lower parts of each withdrawable element there are contacts of the high-voltage circuit breaker, which are able to drive the withdrawable element into the working position and roll out In this case, it is possible to close or disconnect with busbar and linear fixed contacts, which makes it possible to connect or disconnect the high-voltage circuit breaker from busbars and cable connections, characterized in that on each withdrawable element, in addition to the high-voltage circuit breaker, current transformers and a control unit for the high-voltage circuit breaker are placed, and in the cell there are curtains which, when the withdrawable element is rolled out of it, automatically block access to the bus and line contacts that remain energized, current-carrying busbars inside the cell are separated by insulating partitions, cable connections can be made both from the rear side of the cell, and inside the cell above and below, and stationary grounding conductors installed in the cell for grounding cable connections or busbars are equipped with an accelerated mechanism inclusion, while in the cell there are a number of locks, which, inter alia, do not allow the withdrawable element to be moved from the working position to the control and from the control the working position when the high-voltage switch is on, do not allow the high-voltage switch to turn on when the withdrawable element is in the intermediate (between the operating and control) position, do not allow the withdrawable element to move from the control position to the operating position when the earthing knives are on, do not allow the earthing switch to turn on when the circuit breaker, do not allow separation of current circuits on the withdrawable element in the working position, and do not allow the withdrawable element to move that of the reference to working position without the set and locked connector.