JPS58144514A - Gas insulated dc bus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a gas nine-edge DC bus used in a super-crossover @conversion station.

Conventional AC/DC converter stations are configured with equipment based on air insulation. However, in recent years, there has been a trend toward higher power generation power systems.
When transmitting large amounts of power to a remote location, even in the case of direct current, there is an increase in the retransmission pressure just as with alternating current, and it has already reached ±250.
A KV class AC/DC converter station is being constructed.

FIG. 1 shows a single line diagram of such an AC/DC converter station. In Figure 1, 1 is the double busbar on the AC side, and 2 is this two bus line.
A plurality of busbar switching disconnectors are provided in pairs between the double busbars, and 3 is an AC breaker provided on both sides of the double busbar connection via connection disconnectors 4. The heavy busbar 1, the busbar switching disconnector 2, the AC breaker 3, and the linking disconnector 4 constitute an AC side switching device of a double busbar 4 bus tie system. Further, 5 is a thyristor valve for converting alternating current into direct current, 5a is a low pressure stage, 5b is a high pressure stage, and 6 is a DC side winding at each input terminal of the low pressure stage and high pressure stage 5b of the thyristor valve 5. a converting transformer, 8 whose AC side winding is connected between the pair of busbar switching disconnectors 2 through the AC side breaker 7;
is a DC reactor provided on the output side of the thyristor valve 5, and 9 is a neutral line side disconnector provided on the neutral line side of the thyristor valve 5. These thyristor valve 5, conversion transformer 6, and DC reactor 8 , and the neutral line side disconnector 9 constitute a conversion unit. Furthermore, 10 and 11 are a double-configured anode-side main busbar and a cathode-side main busbar, and 12 is a neutral line forming a return conductor of the thyristor valve 5. 13
Reference numeral 14 indicates a plurality of DC-side bus switching disconnectors provided in pairs between the anode side main buses 10, and 14 a DC breaker connecting the anode side main buses 10 via disconnectors 15 on both sides thereof. , 16 are a plurality of DC side bus bar switching and disconnecting switches provided in pairs between the cathode side main bus bars 11, 1
Reference numeral 7 denotes a DC breaker that connects the cathode side main bus bars 11 via disconnectors 18 on both sides, and these anode, cathode side main buses 1o, 11, neutral wire 12, and DC side bus switching disconnector 13°. 16. DC breaker 14.17 and disconnector 15.
18 constitutes a DC side switching device.

One output end of the thyristor valve 5 is connected to the anode branch bus 20 via the DC reactor 8 and the DC breaker 19 between one set of DC side bus switching disconnectors 13 of the anode side main bus 10. The other output end of the thyristor valve 5 is connected to the cathode branch bus 21 via the DC reactor 1v8 and the DC breaker 19 between the DC side bus switching disconnectors 16 of the cathode side main bus 1101. Further, the neutral line side end of the thyristor valve 5 is connected to the neutral line 12 via a neutral line side disconnector 9. On the other hand, 22 is the AC side mother #! an AC filter, 24, connected between the busbar switching circuit devices 2 of other sets of l, via an AC breaker 23;
is a phase adjustment equipment connected via an AC breaker 25 between the bus bar switching disconnectors 2 of another set different from the above,
Reference numeral 26 designates an AC side cable head connected between another set of bus bar switching disconnectors 2, which is also different from the above, via a disconnector 27 and an AC breaker 28. Also, 29
is the DC side bus bar switching disconnector 1 of the other set of the anode side main bus bar 10
DC anode side cable head 32 is connected to the neutral wire 12 through a disconnector 33 and a DC breaker 34, and the DC neutral wire head is connected to the neutral wire 12 through a disconnector 33 and a DC breaker 34. Cable head 35 is a DC fiber connected between both J:Ha cable heads 29,32.

By the way, in an AC/DC converter station with the wiring configuration as shown below, if the equipment and busbars are installed based on air insulation,
Since the pulp building housing the thyristor valve 5 as well as the alternating current and direct current switching devices occupy a large area, it is required to reduce the size of these devices as much as possible. In particular, the DC switchgear is shown in FIG. 1 as follows: thyristor valve 5, DC reactor 8, DC reactor 8 and DC breaker 19.
, a branch bus 20, 211 connecting the DC breaker 19 and the anode and cathode side main bus 10.11, anode and cathode side main bus 10,
11. If the neutral wire 12 and the like are configured with air insulation, a large insulation space is required.

The present invention has been made in view of the circumstances as described above.The purpose of the present invention is to store a DC high voltage conductor together with a high voltage insulating gas in an airtight metal container, thereby significantly downsizing the converter station and saving space and economy. The present invention provides a gas-insulated DC bus bar that greatly contributes to the direction of insulation performance and improves insulation performance by making the center axis of the DC high-voltage conductor eccentric to the center axis of the airtight metal container. It is.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. Figure 2 shows a DC high voltage conductor 4 inside a cylindrical airtight metal container 41.
2 is arranged so that its central axis is eccentric with respect to the central axis of the airtight metal container, and is housed together with a gas having excellent insulating properties. Further, in FIG. 3, the DC high voltage conductor 42 is supported by a post-type insulating spacer 43, and a trap 45 for capturing dust is provided. That is, the conductor 42 is fixed to four parts provided in the metal container 41. The opening of the recess is fixed via a support flange 44 having a through hole 44a having a U-shaped cross section.
It is occluded through 7. A trap 45 is formed between the seven flange 44 and the lid 46.

Therefore, with a DC bus having such a configuration, the DC high voltage conductor is housed together with high voltage insulating gas in the airtight metal container 41, so the insulation distance between the DC high voltage conductor 42 and the grounded metal container 41 is kept close to the airtight metal container 41. The size can be significantly reduced compared to the medium insulation method, and the entire structure can be made compact. Due to this, the DC busbar is connected to the thyristor pulp 5 and the DC reactor 8, the DC reactor 8 and the DC breaker 19, shown in FIG.
Branch busbars 20, 21 connecting DC breaker 19 and anode and cathode side main busbars 10 and 11, anode and cathode side main busbars 10 and 1
1. If adopted for bus bar configuration such as neutral line, the entire DC switchgear can be significantly reduced, contributing greatly to space saving and economical efficiency.

Further, as shown in FIG. 2, the centers l1II of the DC high voltage conductor 42 and the airtight metal container 41 are eccentrically set by the eccentricity value,
In addition, by arranging the DC high voltage conductor 42 on the L side of the central axis of the airtight metal container 41, the electric field strength on the surface of the DC high voltage suppressing conductor 42 is higher on the outer side, and is lower than that on the lower side. This leads to a decrease in insulation strength as a DC bus bar. This is because in the case of DC insulation, it has been reported that the presence of minute dust significantly reduces the insulation strength to about 80 inches compared to the AC P3 edge.

Further, fine dust accumulates on the bottom surface of the airtight metal container 41 when the bus bar is placed horizontally -fc. Therefore, it is effective to keep the electric field strength below the surface of the conductor and the bottom of the metal container low by eccentrically centering the DC high voltage conductor 42, and as a result, when using airtight metal containers with the same diameter, The 6ED performance is better than that of a structure in which DC high voltage conductors are coaxially arranged with their central axes aligned.

Furthermore, as shown in FIG. 43 and a trap 45 for capturing minute dust is provided at the bottom thereof, it is possible to completely suppress the influence of minute dust generated in the container on the insulation performance.

In the present invention, another metal container connected to this metal container is often arranged at the end of the metal container of the bus bar. In such a case, a disk-shaped or cone-shaped insulating spacer is used to partition the gas between the two metal containers and to support the conductor. In this spacer portion, it is preferable to deviate the conductor so that it is concentric with respect to the metal container.

As described above, according to the present invention, a DC high-voltage conductor is housed in an airtight metal container together with a gas having excellent insulation performance, and the high-voltage conductor is placed so that its central axis is on the base side of the central axis of the container. By arranging the converter so as to be eccentric, it greatly contributes to the downsizing of the converter station as a whole and improves economic efficiency, and also provides a gas insulated DC bus with excellent insulation performance.

[Brief explanation of the drawing]

Fig. 1 is a single line diagram showing an example of the configuration of an AC/DC converter station, Fig. 2 is a cross-sectional view for explaining the present invention, and Fig. 3 is a configuration diagram showing a specific embodiment of the present invention. . 44...Airtight metal container 42...DC high voltage conductor 43...Post type insulating spacer 44...Support 7 flange 45...Minute dust trap 46...Lid 47...0 ring

Claims (1)

[Scope of Claims] (1) A DC high voltage conductor is placed in a cylindrical airtight metal container that is grounded at the 4th position in parallel with the longitudinal direction of the grounded metal container so that its center axis is relative to the center axis of the metal container. A gas-insulated ship DC bus bar that is eccentrically arranged and housed together with a gas that has excellent insulation properties. (2. In the item described in claim 1, the gas-insulated single-phase DC bus is arranged horizontally, the DC high voltage conductor is cylindrical, and the vertical axis passing through the center is the center of the cylindrical metal container. A gas-insulated direct current busbar eccentrically arranged so that the vertical axis Y passing through the conductor and the metal container coincide with each other, and the horizontal axes of all the conductors are aligned with each other. A gas-insulated DC bus bar characterized in that at least one location of the DC high-voltage conductor is fixed to an airtight metal container using a post-type insulating spacer. (4) The airtight metal container according to claim 2. A gas insulated DC bus bar characterized by having a trap for capturing minute dust at a location where a post-type insulating spacer is fixed on the inside.