JPH05122813A - Gas insulated transmission line - Google Patents

Abstract

PURPOSE:To obtain a three-phase two-line phase isolated gas insulated transmission line in which steady operation can be sustained by recovering the system quickly upon occurrence of internal fault. CONSTITUTION:A normal operating phase isolated gas insulated transmission lines 4a, 4b are provided, at the ends thereof, with apparatus 6a, 6b for disconnecting faulty phase and disconnectors 9a, 9b for connecting a single phase stand-by transmission line 5, laid along the gas insulated transmission lines 4a, 4b, with the faulty phase. Upon occurrence of fault, the disconnecting apparatus 6a, 6b and the disconnectors 9a, 9b are operated to switch the faulty phase to the single phase stand-by transmission line 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-insulated power transmission line to which a phase-separated gas-insulated power transmission line (hereinafter referred to as GIB) is applied, and particularly to a GIB structure having a spare line for GIB accident response. It is about.

[0002]

2. Description of the Related Art In recent years, two lines of power transmission lines have been used in the main system from the viewpoint of preventing disconnection of the route of the power transportation route. The power is transmitted through one line to prevent power failure due to an accident.

On the other hand, there is an example in which GIB is applied to a transmission line and the transmission line is laid in a cave while a demand for electric power is increasing in recent years and an ultra-high voltage and ultra-high voltage system is being introduced into the city center. It has increased.

FIGS. 5 and 6 show a conventional power transmission line of this type. FIG. 5 shows a single-line connection diagram during two-line power transmission, and FIG. 6 shows a device layout of the circuit shown in FIG. a is a plan view and b is a front view.

In the drawing, reference numeral 1 denotes a switchgear yard, which is provided with the devices described below. That is, 11a, 11
Reference numeral b is a line side circuit breaker that opens and closes the connection between the GIBs 4a and 4b, which will be described later, and the external power transmission line, 12a and 12b are line side grounding switches, and 13a and 13b are lightning protection devices.

Reference numeral 2 denotes a GIB for a power transmission line, which is composed of a cave 3 and GIBs 4a and 4b having three-phase two lines.
The GIBs 4a and 4b are laid using a large insulating support (not shown) in a metal container filled with a high dielectric strength gas.

The transmission line having the structure shown in FIGS. 5 and 6 is
It has GIBs 4a and 4b consisting of three-phase two lines, and normally, both lines are used for power transmission. Even if one line, for example, the GIB 4a causes an accident and the power transmission becomes impossible, the power is transmitted only by the sound GIB 4b, and operation is performed so as not to cause a power failure accident.

[0008]

The conventional gas-insulated transmission line is constructed as described above, and since the main circuit part is housed in the metal container, it is difficult to locate the accident point in the event of an accident. However, there was a problem that it took time to recover from the accident, and during that period, the system reliability had to be greatly reduced, and one line operation had to be performed. One possible solution is to add one additional GIB line, three-phase three-times configuration, and use one line as a standby line, but the economic probability of investing in equipment is extremely low because of the extremely low accident probability. Few.

The present invention has been made in view of the above problems, and pays attention to the fact that an internal accident in a phase-separated GIB has no influence on other phases and lines except for the accident phase. However, even if an internal accident occurs, it is an object of the present invention to obtain a gas-insulated transmission line that can be operated in a steady state and has low equipment cost by promptly switching the accident phase to the one-phase backup transmission line.

Another object of the present invention is to detect an accident phase,
An object of the present invention is to obtain a gas-insulated transmission line capable of performing a quicker switching operation by remotely switching the accident phase to the one-phase backup transmission line.

[0011]

A gas-insulated transmission line according to the present invention is provided with a first switch for disconnecting an accident phase at each end of a three-phase two-line transmission line, and a three-phase two-line transmission line. The second switch is provided for switching the one-phase standby transmission line provided with the line to the fault phase. In addition, a gas-insulated transmission line according to another invention is provided with a first switch for separating an accident phase at each end of a three-phase two-line transmission line, and a one-phase side-by-side connection with a three-phase two-line transmission line. A second switch is provided to switch the standby transmission line to the accident phase.
According to the detection output of the detection device for detecting the accident phase, the first and second switches are remotely operated.

[0012]

In the present invention, by operating the first and second switches, the accident phase can be promptly switched to the one-phase standby transmission line to enable steady operation. Further, in another invention, by remotely operating the first and second switches, the accident phase is switched to the one-phase standby power transmission line more quickly, and the steady operation is enabled.

[0013]

EXAMPLES Example 1. Embodiments of the present invention will be described below with reference to the drawings. First Embodiment FIG. 1 is a single line connection diagram showing a first embodiment of the present invention, and FIG. 2 shows an arrangement configuration of equipment corresponding to FIG.
a is a plan view and b is a front view. Further, FIG. 3 is a configuration diagram showing an example of GIB arrangement in the cave. In FIG.
The wiring part indicated by a thick line indicates a device three-phase portion, the wiring part indicated by a thin line indicates a device single-phase portion, 1 is a switchgear yard, and 2 is a transmission line GIB.

The main equipment structure is the same as that of the conventional apparatus shown in FIGS. 5 and 6, but the GI for the power transmission line in the present invention.
B2 additionally includes a one-phase backup power transmission line 5 provided in parallel with the GIBs 4a and 4b for normal operation. Therefore, the disconnecting device 6 is installed in each of the phases at the end portions of the GIBs 4a and 4b for normal operation. The connection of the 1-phase backup power transmission line 5 at the time of the accident is performed by the lightning arresters 13a and 13b and the line-side grounding switch 12
It is carried out via the phase separation type disconnectors 9a and 9b provided between the a and 12b.

Now, if an internal accident occurs in one phase of the GIB 4a for normal operation, a protection device (not shown) is activated to open the line side circuit breaker 11a. Therefore, after determining the accident phase and disconnecting the line of the accident phase by the disconnecting device 6a, the phase separation type disconnector 9a corresponding to the accident phase is closed, and then the line side circuit breaker 11a is closed. Try to recover.

FIG. 3 shows an example of arrangement of GIBs installed in the cave 3 shown in FIG.
b is installed in the lower part of the cave, and the one-phase backup power transmission line 5 and the cooling water pipe 10 are installed in the upper part of the cave. By arranging in this way, the one-phase backup power transmission line 5 can be installed without hindering the equipment drawing space 11 and the maintenance / inspection space 12, and without increasing the diameter of the cavern.

As described above, the transmission line is a phase-separated GIB.
In the system configured as described above, by installing the one-phase backup power transmission line 5 in parallel with the GIBs 4a and 4b for normal operation for emergency response, system switching in the event of an accident can be quickly achieved. The equipment installation space in the cave is the same as the conventional 2-line GI
There is not much difference from the B installation, and therefore the diameter of the sinus is not increased.
In terms of cost, it can be reduced to about 1/3 of the case where one line is added as a spare. Etc., and as a result, an effect comparable to the case where three-phase protection lines are installed by installing only one-phase protection transmission line 5 is obtained.

Example 2. As another embodiment 2, in the above-mentioned embodiment 1, after the accident in the GIBs 4a, 4b for normal operation is confirmed, the system is restored by switching to the one-phase backup transmission line 5, but the CT for accident localization in the GIB is mainly protected. FIG. 4 shows an embodiment in which a means for automatically restoring the system is provided separately from the CT for use.

In FIG. 4, 130a and 130b are CTs for main protection, 14a and 14b are Cs for locating an accident point in the GIB.
T, 15a and 15b are operated by a distant power operation G
The IB disconnecting disconnecting device, 16a16b, also represents a disconnecting disconnecting switch for switching to the one-phase backup transmission line 5 which is also remotely operated.
If an internal accident occurs in the normal operation GIB 4a and the single-phase reclosing fails, the disconnecting switch 15a is quickly opened and the disconnecting switch 16a is closed by the distant power operation, and the accident phase and the 1-phase standby transmission line 5 are connected. , And reclosing is possible again.

That is, a 1-phase standby transmission line, a GIB fault point locating CT, a GIB disconnecting disconnecting switch for normal operation, and 1
By installing the disconnector for switching the phase standby transmission line,
Even if a line accident occurs, the same effect as having one circuit in reserve can be obtained.

[0021]

As described above, according to the present invention, the first switch for disconnecting the accident phase is provided at each phase of the end portion of the three-phase two-line power transmission line, and the three-phase two-line power transmission line is provided. Since the second switch for switching the attached 1-phase backup power transmission line to the fault phase is provided, by operating the first and second switches described above, the fault phase can be quickly switched to the 1-phase backup power transmission line. To enable steady operation. Further, according to the present invention, since the first and second switches are remotely operated by the detection output of the detection device for detecting the accident phase, the accident phase can be detected more quickly.
Switch to the phase backup transmission line to enable steady operation.

[Brief description of drawings]

FIG. 1 is a single wire connection diagram of a gas insulated transmission line according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an arrangement configuration of devices corresponding to FIG.
a is a plan view and b is a front view.

FIG. 3 is a configuration diagram showing an arrangement example of a phase-separated gas-insulated transmission line in a cave according to the present invention.

FIG. 4 is a single wire connection diagram of a gas insulated transmission line according to a second embodiment of the present invention.

FIG. 5 is a single wire connection diagram of a conventional gas insulated transmission line.

FIG. 6 is a diagram showing an arrangement configuration of devices corresponding to FIG.
a is a plan view and b is a front view.

[Explanation of symbols]

 11a, 11b Line-side circuit breaker 3 Cave 4a, 4b Phase-separated gas-insulated transmission line 5 1-phase auxiliary transmission line 6a, 6b Separation device 9a, 9b Phase-separated disconnector

Claims (2)

[Claims] 1. A three-phase two-line transmission line laid in a metal container in which a high dielectric strength gas is sealed, a line-side circuit breaker connected between the three-phase two-line transmission line and an external transmission line,
A first switch provided in each phase at the end of the three-phase two-line power transmission line, a one-phase standby power transmission line provided in the metal container together with the three-phase two-line power transmission line, the line side A gas-insulated transmission line, comprising: a second switch that selectively connects one of the phases between the circuit breaker and the first switch to the one-phase standby transmission line. 2. A three-phase two-line transmission line laid in a metal container in which a high dielectric strength gas is sealed, a line-side circuit breaker connected between the three-phase two-line transmission line and an external transmission line,
A first switch provided in each phase at the end of the three-phase two-line power transmission line, a one-phase standby power transmission line provided in the metal container together with the three-phase two-line power transmission line, and the three-phase A current transformer that transforms the current of a two-line power transmission line, a second switch that selectively connects one of the phases between the line-side breaker and the first switch to the one-phase standby power transmission line A detector, a detector for monitoring the transformed current of the current transformer and detecting an accidental phase, and an operating means for remotely operating the first and second switches according to the detection output of the detector. Gas-insulated transmission line characterized by.