JPH071973B2 - Phase-separated closed bus - Google Patents

Description

TECHNICAL FIELD The present invention relates to a phase-separated closed busbar in which an electric conductor of each phase is housed and arranged in a metal container in which each phase is independent.

[Conventional technology]

FIG. 3 is a system diagram showing a conventional phase-separated closed bus ventilation system disclosed in, for example, Japanese Utility Model Laid-Open No. 52-25305. In the figure, (1) shows a compressor as an air generating means for generating compressed air, and (2) shows that the compressed air supplied from this compressor is on the inlet side and the outlet side pressure is lower than the inlet side pressure. A pressure reducing valve that adjusts to a set pressure, (3) a flow rate control valve that controls the flow rate of compressed air decompressed by this pressure reducing valve to a constant flow rate, and (4) a pressure between the outlet side pressure of the flow rate control valve and atmospheric pressure. A switch as a diaphragm type pressure detecting means for detecting a difference, and when a predetermined set pressure difference is reached, an electric contact operates. (5a), (5b), and (5c) are phase-separated closed busbars for A-phase, B-phase, and C-phase metal containers (metal container (5) when collectively referred to), to which dry air is supplied. There is an air supply hole and a manhole for inspection. (6) is a metal container for each phase (5a) (5b) (5)
It is a pipe for supplying air to c).

The conventional phase-separated closed bus bar is configured as described above, and the dry air compressed by the compressor (1) passes through the pressure reducing valve (2) and the flow control valve (3) and the metal container (5a) for each phase.
Air is supplied to (5b) and (5c). Each phase metal container (5a) (5b)
(5c) is configured such that air slightly leaks from a seal part such as a manhole that is tightened through a packing, and this seal part serves as a vent hole for communicating with the outside air communicating with the atmosphere. ing. The dry air supplied to each phase metal container (5a) (5b) (5c) discharges the internal air from the sealed portion into the atmosphere, and each phase metal container (5a) (5b) ( Scavenging the inside of 5c). Therefore, the pressure in each phase metal container (5a) (5b) (5c) becomes slightly higher than atmospheric pressure to maintain equilibrium, and each phase metal container (5a)
(5b) Prevents ingress of dust and moisture into (5c). In addition, in order to confirm that the phase-separated closed busbar is operating normally, a pressure switch (4) is provided on the outlet side of the flow control valve (3), and each phase metal container (5a) (5b) (5c ) Common pressure is being monitored.

[Problems to be solved by the invention]

In the conventional phase-separated closed bus bar as described above, the pressure switch (4) is provided at the outlet side of the flow control valve (3) and the pipe for supplying air to each phase metal container (5a) (5b) (5c) is supplied. Since it is provided in each phase common part, for example, the packing of the metal container (5) is damaged or deteriorated, and more air than necessary leaks out.
Even if the pressure drops, it is not possible to identify which phase the metal container (5) is related to, and the pipe (6) between the pressure switch (4) and each phase metal container (5a) (5b) (5c). ) Is long, there is a pressure loss, and even if a certain amount or more of air leaks into any of the metal containers (5), there is a problem that it cannot be monitored accurately depending on the degree. .

This invention was made in order to solve such a problem, and if there is a predetermined amount or more of air leaking into the metal container, it is possible to immediately identify which phase the metal container is (5a) ( 5b) The purpose is to obtain a phase-separated closed busbar that can accurately monitor the pressure in each phase metal container even if the piping to (5c) is long.

[Means for solving problems]

The phase-separated closed bus according to the present invention is a flow control means for controlling the flow rate of the air supplied from the air supply means to each phase metal container for each phase metal container and the pressure in each phase metal container for each phase metal container. A pressure detecting means for detecting each of them is provided.

[Action]

In the present invention, since the flow rate of the air supplied by the flow rate control means is controlled for each phase metal container, when there is a predetermined amount or more of air leakage in each phase metal container, each phase metal of another phase The influence of the pressure change on the container is small, and the pressure of each phase metal container decreases. Therefore, it is possible to accurately detect the decrease in the internal pressure of each phase metal container by the pressure detection unit that detects the pressure for each phase metal container, and to identify each phase metal container that has leaked air of a predetermined amount or more. it can.
Further, even if the air piping to each phase metal container is long, the pressure can be detected with good sensitivity without lowering the detection sensitivity due to the pressure loss.

〔Example〕

FIG. 1 is a scavenging system diagram showing an embodiment of the present invention,
(1), (2), (5a), (5b) and (5c) are exactly the same as the above conventional device. (13a), (13b), (13
c) are metal containers (5a) (5b) (5) for A-phase, B-phase, and C-phase, respectively.
A), B-phase, and C-phase flow control valves that control the flow rate of air to c) (collectively referred to as a flow control valve as flow control means (13)), (14a) (14b) (14c) Are phase A, phase B,
A attached to a C-phase metal container (5a) (5b) (5c)
Phase, B phase, and C phase pressure switches (collectively referred to as pressure switches (14)), each phase metal container (5a) (5b) (5
It is a diaphragm type that detects a relatively small pressure difference between the internal pressure and atmospheric pressure, and the electrical contact operates when a predetermined set pressure difference is reached. Pipes (16a), (16b), and (16c) are connected to the A-phase, B-phase, and C-phase metal containers, respectively.

In the phase-separated closed bus bar configured as described above, the dry air compressed by the compressor (1) is the pressure reducing valve (2) and the flow control valve (13a) as in the conventional phase-separated closed bus. (13b) (13c) Each phase metal container (5a) (5
b) Air is supplied to (5c), and the air inside the phase is exhausted to the atmosphere through the air vent that is the sealing part, and the inside of each phase metal container (5a) (5b) (5c) is scavenged. . For this reason, the pressure in each phase metal container (5a) (5b) (5c) becomes slightly higher than atmospheric pressure to equilibrate and prevent ingress of dust and moisture into the interior, and each phase metal container (5a) (5b) (5
Pressure switch (14a) as pressure detection means provided in c)
Each pressure is monitored by (14b) and (14c). If more than necessary air leaks in the metal container (5) of either phase and the pressure drops, the pressure switch (1
Since the electrical contact of 4) operates and issues an abnormal signal, it is possible to immediately identify the abnormal phase. In the case of this embodiment, the metal container (5) for each phase and the flow control valve (13)
The pipes (16) may be long apart from each other.

FIG. 2 shows another embodiment of the present invention, in which pipes common to each phase are provided up to the vicinity of the metal container (5) and connected to the metal containers (5a) (5b) (5c) of each phase. 3 pipes, and each phase flow control valve (13a) (13b) in the middle of each pipe
(13c) and each phase pressure switch (14a) (14b) (14c) are provided, and the same effect as the above embodiment is produced. In the case of this embodiment, the pipes between the compressor (1), the pressure reducing valve (2) and the flow control valves (13a) (13b) (13c) of each phase may be long, but each phase metal container (5a). (3) The three pipes connected to (5b) and (5c) must be of such a diameter that pressure loss due to air flow can be ignored.

Further, in any of the above-mentioned embodiments, the pressure detecting means has two pressure detecting means, one having a first pressure set value with a high set pressure and the other having a second pressure set value having a low set pressure. By providing a pressure switch,
For example, when the amount of leaked air exceeds a predetermined amount due to deterioration of the packing, etc., it is detected that the one with the first pressure set value is activated and the amount of leaked air has started to increase, and the deterioration of the packing etc. starts. When the amount of leaked air further increases and the pressure in the metal container decreases, the second pressure set value is activated, and information such as the fact that packing needs to be replaced can be obtained.

〔The invention's effect〕

As described above, the present invention controls the flow rate of the air supplied to each phase metal container of the phase separation type closed bus for each phase metal container and detects the pressure in each phase metal container for each phase metal container. As a result, if any of the metal containers in each phase leaks air above a predetermined value, it is possible to accurately identify which phase it is, and even if the air piping to each phase metal container is long. The effect is that the pressure in each phase metal container can be reliably detected.

[Brief description of drawings]

FIG. 1 is a scavenging system diagram showing an embodiment of the present invention, FIG. 2 is a scavenging system diagram showing another embodiment of the present invention, and FIG. 3 is a system showing a conventional scavenging system of a phase-separated closed bus. It is a figure. In the figure, (1) is a compressor, (2) is a pressure reducing valve, and (5a)
(5b) (5c) are metal containers of A phase, B phase, C phase, (13a) (13
b) (13c) is the A-phase, B-phase, C-phase flow control valve, (14a) (14
b) (14c) are pressure switches for A-phase, B-phase, and C-phase, and (16a) (1
6b) (16c) are metal containers (5a) (5b) (5) for A-phase, B-phase, and C-phase.
It is a pipe connected to c). In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (2)

[Claims] 1. A busbar portion insulatingly supporting an electric conductor of the relevant phase in a metal container having a ventilation portion communicating with the atmosphere independently of each phase, and air for scavenging the air in the metal container. In a phase-separated closed bus which is provided with an air supply means composed of an air generation means for generating and a flow rate control means and a pressure detection means, and is operated by constantly scavenging the air in the metal container, the flow rate control means And a phase-separated closed bus bar, wherein the pressure detecting means is provided for each phase of the metal container. 2. The pressure detecting means comprises a first pressure set value having a high set pressure and a second pressure set value having a low set pressure. The phase-separated closed bus bar described in the item.