JPH027830A - Monitor device of gas insulation type electrical equipment - Google Patents

Abstract

PURPOSE:To detect in which gas partition chamber abnormal heating is in progress from outside in early stage by differentiating the pressure variation between the gas partition chambers and judging the magnitude of pressure variation. CONSTITUTION:Upon occurrence of abnormal overheating in a first gas partition chamber, gas pressure increased P1 at a predetermined time t later is higher by an amount corresponding to thermal pressure increase owing to the overheating than the gas pressure increase P2 in a second gas partition chamber 2. Pressure sensors 8, 8 arranged in the first and second gas partition chambers 1, 2 detect the pressure every predetermined time and the detected pressure is subjected to operation in an operating unit 9. Then the pressure difference P=¦ P1- P2¦ is compared with a reference value P0 in order to judge the normality. If P>= P0, the magnitude of P1, P2 is compared and if P1> P2, it is judged that the first gas partition chamber is overheated while if P1> P2, it is judged that the second gas partition chamber is overheated. Then an abnormality signal is fed to an output device corresponding to the judgement.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a monitoring device for gas-insulated electric equipment such as a gas-insulated switchgear.

[Conventional technology]

A typical gas insulated switchgear is shown in Figure 6. In the figure, 30 is a circuit breaker, 31 is a linear disconnector, 32 is a line grounding device, 33 is a cable connecting device, 34 is a cable splitting through type current transformer, 35 is a bus bar, 36 is a grounding device for inspection,
37 is a right-angled cross-section disconnector, and 38 is a charging section.

The charging part 38 is insulated and supported for three phases by an insulating spacer 39, housed in a metal container, and has a diffused pressure S inside.
F&gas is sealed. SF, gas acts as an insulating and arc-quenching medium. In addition, the insulating spacer 39 supports the charging part 38 and divides the inside of the container into each element to form a plurality of independent gas compartments, so that filling and exhausting of SF and gas is performed only in the necessary parts. It has become.

As a result, high insulation performance can be obtained with small insulation dimensions, and compared to conventional equipment, the volume and installation area of the equipment can be significantly reduced, and it is highly reliable.

[Problem to be solved by the invention]

In this gas-insulated switchgear, a monitoring device is required to promptly detect when abnormal internal overheating occurs.

If a momentary overheating occurs internally and the gas pressure increases, it can be detected by a shock pressure relay. In addition, after overheating continues and progresses for a certain period of time and reaches a certain abnormal level, it can be detected by a pressure switch.

However, in the case of a relatively gradual temperature rise due to a local abnormality, it is not possible to determine whether the temperature rise is due to a change in the applied current or a change in the outside temperature. It was not possible to detect abnormal overheating.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a monitoring device for gas-insulated electrical installations that can easily detect from the outside that abnormal overheating is in progress in any gas compartment.

[Means to solve the problem]

The monitoring device for gas-insulated electrical equipment of the present invention includes first and second gas compartments that are used in the same manner, and the first and second gas compartments that are used in the same manner. A first pressure sensor and a second pressure sensor respectively provided in the second gas compartment; From each output of the second pressure sensor, the first pressure sensor. The pressure changes in each of the second gas compartments are determined, the difference between them is taken, and when this difference exceeds a reference value, the magnitude of each pressure change is determined. and an arithmetic device that outputs an abnormality signal indicating whether any of the second gas compartments is abnormal.

[Effect]

According to this invention, first. The second gas compartment is bill of use B.
Since (outside temperature, current applied) are the same, the pressure changes in both gas compartments are at the same level under normal conditions.

On the other hand, if abnormal overheating occurs in one gas compartment, the pressure change in this gas compartment will appear larger than in normal conditions and therefore in the other gas compartment, so both By measuring the difference in pressure changes, it is possible to detect in which gas compartment abnormal overheating is occurring at an early stage in the progress of the abnormality, without being affected by outside temperature or the like.

〔Example〕

FIG. 1 shows a monitoring device for gas-insulated electrical equipment according to this embodiment. In FIG. 1, a conduit 3 for conducting electricity (indicated by arrow A) is divided into a first gas compartment 1 and a second gas compartment 2 by an insulating spacer 4 for insulating and supporting a live part. Each gas compartment 1.2 is filled with SF and gas.

A pipe 6 having an S F b gas filling/exhaust port 5 is attached to each gas compartment 1.2, and an on-off valve 7 of this pipe 6 is installed.
．． A pressure sensor 8 is provided between 7 and 7.

The pressure sensors 8, 8 provided in each gas compartment 1, 2 are connected to a second
As shown in the figure, it is connected to a computing device 9, and when an abnormality is detected, it is output from the computing device 9 to an output device 10.

Since each of the gas compartments 1.2 is configured to have the same usage conditions (outside temperature, current flow), the gas pressure P in these gas compartments 1.2.

As shown in FIG. 3, P2 changes linearly with almost the same slope as the gas temperature changes. Therefore, the live parts (conductors) in the pipeline 3 including these gas compartments 1 and 2
If a certain current flows and the outside temperature is constant, the gas pressures P, P2 will be stable at a certain pressure value, but in actual operating conditions, they will not follow changes in the outside temperature or the current flowing. As shown in FIG. 4, it shows irregular changes with time.

Under such conditions, if abnormal overheating occurs in the first gas compartment 1, the gas pressure increase value ΔP after a certain time Δ in the gas compartment I will be due to this overheating. The constant time Δ in the gas compartment 2 without abnormal overheating should be higher than the subsequent pressure increase value ΔP2 by the amount of pressure increase.

Next, the operation of the arithmetic unit 9 will be explained based on the flowchart shown in FIG. 1st. Second gas compartment 1.2
The pressure sensor 88 provided at each of ,P, ,-P□.

P Ik-mouth P ZO+ P 2++ P tZ-
”-P!X++1 is detected in P2, and the calculation device
At ΔP, = ! p+, , -p□ 8Pg-Pz□I pzx is calculated. Then, the difference between these ΔP=lΔP−ΔP2
1, compare this ΔP with the reference value ΔP0, and determine whether it is normal or
Determine abnormality. If ΔP≧ΔP0, then ΔP1
, ΔP2 is larger, and ΔP, >ΔP
2, the first gas compartment 1, vice versa, the second gas compartment 1.
It can be determined that abnormal overheating has occurred in each of the gas compartments 2, and according to this determination result, the output device 1
An abnormal signal is output to 0.

〔Effect of the invention〕

According to this invention, first. Since the second gas compartments are under the same operating conditions (outside temperature, current flow), if we calculate the difference in pressure changes after a certain period of time in each gas compartment, we can determine which one is the same without being affected by the outside temperature, etc. This has the effect of being able to detect whether abnormal overheating is occurring in the gas compartment at an early stage in the progress of the abnormality.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram showing the circuit configuration, FIG. 3 is a graph showing the relationship between gas temperature and gas pressure in two gas compartments, and FIG. The figure is a graph showing the relationship between time and gas pressure under actual usage conditions.
FIG. 5 is a flowchart showing the calculation procedure of the calculation device shown in FIG. 2, and FIG. 6 is a sectional view of a normal gas-insulated switchgear. l...first gas compartment, 2-second gas compartment, 3
...Pipe line, 4--Insulating spacer, 8--Pressure sensor 1-・Gas Z drawing of Takumi 1! 2...-62 pressure 1 3-・Government 4・-1 tank space 8-・-Pressure 7') Lorezubus humidity (℃) - Figure 3 Figure 1 Figure 2 Figure 4 Figure 51

Claims (1)

[Claims] First and second gas compartments that are in the same usage state, first and second pressure sensors provided in the first and second gas compartments, respectively, and the first and second pressure sensors. The pressure change in each of the first and second gas compartments is determined from each output of the first gas compartment, the difference between these is determined, and when this difference exceeds a reference value, the magnitude of each pressure change is determined. A monitoring device for gas-insulated electrical equipment, comprising: a computing device that outputs an abnormality signal indicating which of the second gas compartments is abnormal.