CN103840380A - PT2 type power distribution station - Google Patents

Abstract

The invention provides a PT2 type power distribution station. A 10 kV inlet wire is communicated with a first transformer through a set of SF6 load switch blade, and after the10 kV of the inlet wire voltage is converted to 0.4 kV, the 10 kV inlet wire supplies power for a first section of 0.4 kV bus and a plurality of outlet wires which are connected behind the first transformer. The other 10 kV inlet wire is communicated with a second transformer through the other set of SF6 load switch blade, and after the 10 kV of the other inlet wire voltage is converted to 0.4 kV, the other 10 kV inlet wire supplies power for a second section of 0.4 kV bus and a plurality of outlet wires which are connected behind the second transformer. The first section of the bus and the second section of the bus are connected through a section switch. According to the PT2 type power distribution station, primary equipment of the power distribution station is replaced on the premise of not changing the original scale and main wire connecting mode, health level and safe operation level of equipment can be conveniently improved, workload of overhaul and maintenance is reduced, and power supply reliability is improved.

Description

A PT2 type distribution station

technical field

The invention relates to the field of power distribution, in particular to a PT2 type distribution station. the

Background technique

When supplying power to commercial areas and residential buildings, users generally have relatively high requirements for power supply reliability. In some substations put into operation in the 1990s, the main wiring adopts a two-input and two-outlet belt segment method. Figure 1 and Figure 2 show two examples.

As shown in Figure 1, one 10kV incoming line is connected to No. 1 transformer through switch K1, switch K11, and fuse, and then supplies power to a 0.4kV section of busbar connected to No. 1 transformer and its six outgoing lines; the other 10kV incoming line passes through Switch K2, switch K21, and fuses are connected to No. 2 transformer, and then supply power to the 0.4kV second-section busbar and its six outgoing lines connected after No. 2 transformer. Cables with switch K3 and switch K4 are also set up to connect the two 10kV incoming lines.

As shown in Figure 2, the device connection structure on the 0.4kV side is similar to the above, and one incoming line on the 10kV side is connected to No. 1 transformer through switch S1 and switch S11, and the other incoming line on the 10kV side is connected through switch S2 and switch S21 To the No. 2 transformer, the 10kV first and second busbars are connected through the section switch S3, and the two busbars are respectively equipped with lightning arresters.

Figure 3 is the layout diagram of the existing distribution station. Two low-voltage incoming cabinets 1, six low-voltage outgoing cabinets 2, two capacitor cabinets 3 and one low-voltage section cabinet 4 are installed in the low-voltage room to place the 0.4kV side related equipment. Four high-voltage cabinets 6 are placed in the high-voltage room to place the above-mentioned related devices on the 10kV side. Transformers No. 1 and No. 2 are connected to corresponding high-voltage cabinets 6 and low-voltage incoming cabinets 1 through several cables.

However, the devices on the high-voltage side in the prior art (usually implemented by GG1A high-voltage cabinets) are outdated, have no spare parts, and have poor power supply reliability, making it difficult to meet the growing demand for electricity. However, distribution stations that supply power to commercial areas and residential buildings are often limited by the site, making it difficult to expand the scale and difficult to transform.

Contents of the invention

The purpose of the present invention is to provide a PT2 distribution station, which can replace the primary equipment of the distribution station without changing the original scale and main wiring mode, so as to improve the reliability of power supply of the equipment.

In order to achieve the above object, the technical solution of the present invention is to provide a PT2 type power distribution station, which includes:

One 10kV incoming line is connected to the No. 1 transformer through a set of SF6 load switch, and after being converted into 0.4kV, it supplies power for a 0.4kV section of the bus connected behind the No. 1 transformer and its multiple outgoing lines;

The other 10kV incoming line is connected to the No. 2 transformer through another set of SF6 load switch blades, and after being converted into 0.4kV, it supplies power for the 0.4kV second-section bus and its multiple outgoing lines connected after the No. 2 transformer; the first section of the bus and the second section The busbars are connected through section switches.

Preferably, the SF6 load switch is set in the SF6 ring network cabinet.

Preferably, one end of the SF6 load switch is connected to the 10kV incoming line through a copper busbar, and the other end of the SF6 load switch is divided into two paths through a fuse and a current transformer, one path is grounded through a capacitor, and the other path is connected to The outgoing terminal is further connected to the No. 1 or No. 2 transformer through the outgoing cable.

Preferably, one end of the SF6 load switch is connected to the 10kV incoming line through a copper busbar, and the other end of the SF6 load switch is divided into three circuits after passing through a current transformer, two of which are respectively connected to the grounded capacitor and the lightning arrester, and the other Connect to outlet.

Preferably, the neutral point grounding form of No. 1 and No. 2 transformers is direct grounding; a set of lightning arresters are respectively installed on the high voltage sides of No. 1 and No. 2 transformers.

Preferably, the low-voltage side of No. 1 transformer is connected to a section of 0.4kV bus through a distribution switch, and each outlet of the section of bus is respectively equipped with an outlet switch;

The low-voltage side of the No. 2 transformer is connected to the 0.4kV second-section bus through another distribution transformer switch, and each outlet of the second-section bus is equipped with an outlet switch;

Two sets of capacitors are respectively connected to the first-stage busbar and the second-stage busbar through corresponding capacitor switches; the distribution transformer switch, outlet switch, and capacitor switch are vacuum circuit breakers.

Preferably, two sets of high-voltage cabinets respectively equipped with SF6 load switch knives are located in the high-voltage chamber;

Two low-voltage incoming line cabinets with corresponding distribution transformer switches, six low-voltage outgoing line cabinets with corresponding outgoing line switches, two capacitor cabinets, and one low-voltage section cabinet with section switches are located in the low-voltage room;

Transformers No. 1 and No. 2 are respectively connected to the high-voltage cabinet in the high-voltage room through corresponding incoming and outgoing cables, and connected to the low-voltage incoming cabinet in the low-voltage room through low-voltage copper bus bars.

Compared with the prior art, the PT2 type distribution station provided by the present invention replaces the primary equipment of the distribution station without changing the original scale and main wiring mode, and is equipped with SF6 load switch and SF6 alarm device , which is conducive to improving the health level and safe operation level of the equipment, reducing the workload of inspection and maintenance, and improving the reliability of power supply.

Description of drawings

Figure 1 and Figure 2 are two schematic diagrams of electrical wiring in existing distribution stations;

Figure 3 is a plan layout of the existing distribution station;

Fig. 4 is the electrical wiring schematic diagram of a main wiring in the PT2 type power distribution station of the present invention;

Fig. 5 is the electric connection schematic diagram of PT2 type power distribution station of the present invention;

Fig. 6 is a plane layout diagram of the distribution station of the present invention.

Detailed ways

As shown in Figures 4 and 5, the present invention provides a PT2 type distribution station (PT2 type, that is, a ring network distribution station with 2 transformers and 10kV outgoing lines), the main wiring still adopts two-input and two-outlet with segments Way. That is, one 10kV incoming line is powered by 10kV/0.4kV No. 1 transformer, 0.4kV busbar and its six outgoing lines, and the other 10kV incoming line is 10kV/0.4kV No. 2 transformer, 0.4kV second-section busbar and its six outgoing lines powered by. The 0.4kV first and second busbars are connected through a section switch.

Two sets of 10kV high-voltage cabinets (A and B) are located in the high-voltage chamber, respectively using SF6 load switches and equipped with spring operating mechanisms to connect or disconnect the corresponding 10kV incoming lines through the load switches.

In this example, the above-mentioned 10kV high-voltage cabinet adopts the SF6 ring network cabinet as shown in Figure 4. There are two switchgears using the following devices: One end of the SF6 load switch is connected to the 10kV incoming line through a copper busbar, the other end of the SF6 load switch is grounded through a capacitor through a fuse and a current transformer, and the other end is grounded through a capacitor. Then it is connected to the outlet terminal, and then can be connected to No. 1 or No. 2 transformer through the outlet cable; each switch cabinet is also equipped with SF6 pressure indicator, capacitor voltage indicator, short-circuit fault indicator, three-position switch auxiliary contact, gas Pressure auxiliary contacts, fuse auxiliary contacts, etc.

There are four switchgears using the following another device arrangement: SF6 load switch is connected to the outlet terminal and grounded capacitor and lightning arrester after passing through the current transformer, and can be connected to the transformer through the outlet terminal, or connected to other switch cabinets The devices in the device are matched and connected to meet different wiring needs (for example, the SF6 load switch blades arranged in the above-mentioned way are used as switches K11, K12 or S11, S21, and the SF6 load switch blades arranged in the latter way are used as other switches in the box. switch, cooperate with each other to construct the wiring scheme shown in Figure 1 or Figure 2, etc.).

The short-circuit current level of this period is selected with reference to the previous equipment, that is, the short-circuit current level of 10kV is considered as 20kA. The parameters of the optimal load switch knife are as follows: rated voltage 12 kV, rated current 630 A, rated breaking capacity 346 MVA, rated breaking current 20 kA, dynamic stable breaking current peak value 50 kA, 4-second thermal stable current 20 kA.

In addition, combined with an equipment transformation, the corresponding incoming and outgoing cables were reconnected, and flame-retardant cables were used. For example, ZA-YJV-8.7/10-3X70 cable is used for the incoming line on the 10kV side, and ZA-YJV-8.7/10-3X70 cable is used for the outgoing line of the 10kV distribution transformer. 5*40 flat iron is used for the grounding of the primary equipment of each warehouse, and is connected to the indoor grounding trunk line.

Transformer No. 1 and Transformer No. 2 are two 10kV/0.4kV transformers, which are located in No. 1 and No. 2 distribution room respectively. These two transformers respectively transform their 10kV incoming line voltage into 0.4kV output, and the neutral point of the transformer is grounded. for direct grounding. A set of lightning arresters are respectively installed on the high-voltage side of the No. 1 and No. 2 transformers to play the role of lightning protection.

All switches on the 0.4kV side are located in the 0.4kV switch room, and all use vacuum circuit breakers. Each switch can connect or disconnect the corresponding outgoing line or its power supply part. The power distribution station of the present invention is provided with 2 distribution transformer switches, 12 outlet switches, 2 capacitor switches, and 1 0.4kV section switch.

That is, the 0.4kV low-voltage side of No. 1 transformer is connected to the 0.4kV first-section busbar through the distribution transformer switch Q31, and there are 6 outlet switches Q41 under it; the 0.4kV low-voltage side of No. 2 transformer is connected to the 0.4kV second-section busbar through the distribution transformer switch Q32. Set another 6 outgoing line switches Q42; 0.4kV section 1 and section 2 busbars set section switch Q5.

The two sets of capacitors play the role of reactive power compensation and are installed in two capacitor cabinets respectively, and are connected to the 0.4kV first and second busbars through corresponding capacitor switches.

As shown in Fig. 6 is the plan layout of the distribution station of the present invention, two groups of six 10kV high-voltage cabinets 6 (SF6 ring network cabinets) are located in the high-voltage chamber. Two 0.4kV low-voltage incoming line cabinets 1 (such as GGD2-02) with corresponding distribution transformer switches, six 0.4kV low-voltage outgoing line cabinets 2 (such as GGD2-38) with corresponding outgoing line switches, and two capacitor cabinets (such as GGD) 3. A low-voltage section cabinet (such as GGD2-02) with a 0.4kV section switch and several low-voltage copper busbars 5 (TMY-100×10) are located in the low-voltage room. Transformer No. 1 and Transformer No. 2 are respectively connected to corresponding equipment in the high-voltage room and the low-voltage room through incoming and outgoing cables.

According to the pollution level of the station site, the creepage ratio distance of the project equipment in this phase is selected according to Class III, that is, the creepage ratio distance of equipment with 10V and below is considered as 31mm/kV outdoors and 25mm/kV indoors. Fireproof sealing shall be carried out at all cable holes and gaps at the bottom of newly added power distribution device rooms and protective screen cabinets, as well as at cable interlayers, wall-through floors, walls, cabinets, and panels involved in cable renovation and new additions. And the cable sheath within 1m on both sides of the blockage shall be pasted with fireproof tape or coated with fireproof paint.

As shown in Figure 3 and Figure 6, in this example, the existing station site can be rebuilt without additional land acquisition, and the equipment in the high-voltage room of the distribution station needs to be replaced, while the equipment in the low-voltage room and its connection layout can be Use the original method to effectively reduce the workload.

To sum up, the PT2 type distribution station provided by the present invention replaces the primary equipment of the distribution station without changing the original scale and main wiring mode, and installs SF6 load switch blades and is equipped with SF6 alarm devices. It is conducive to improving the health level and safe operation level of equipment, reducing the workload of inspection and maintenance, and improving the reliability of power supply.

Although the content of the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description should not be considered as limiting the present invention. Various modifications and alterations to the present invention will become apparent to those skilled in the art upon reading the above disclosure. Therefore, the protection scope of the present invention should be defined by the appended claims.

Claims (7)

1. a PT2 type power distribution station, is characterized in that, comprises:

One road 10kV inlet wire is communicated with No. 1 transformer by a set of SF6 load plug-in strip, converts to after 0.4kV as being connected to mono-section of bus of 0.4kV and many outlets power supplies thereof after No. 1 transformer;

Another road 10kV inlet wire is communicated with No. 2 transformers by another set of SF6 load plug-in strip, converts to after 0.4kV as being connected to bis-sections of buses of 0.4kV and many outlets power supplies thereof after No. 2 transformers; Between described one section of bus and two sections of buses, be connected by block switch.

2. PT2 type power distribution station as claimed in claim 1, is characterized in that,

Described SF6 load plug-in strip is arranged at SF6 ring main unit.

3. PT2 type power distribution station as claimed in claim 1, is characterized in that,

One end of described SF6 load plug-in strip is connected with 10kV inlet wire by copper bus-bar, this SF6 load plug-in strip other end is by after fuse, current transformer point of two-way, lead up to capacity earth, another road is connected to leading-out terminal and is connected to No. 1 or No. 2 transformers by outlet cable.

4. PT2 type power distribution station as claimed in claim 1, is characterized in that,

One end of described SF6 load plug-in strip is connected with 10kV inlet wire by copper bus-bar, and this SF6 load plug-in strip other end is by Fen San road after current transformer, and two-way is connected to respectively electric capacity and the lightning arrester of ground connection, and another road is connected to leading-out terminal.

5. the PT2 type power distribution station as described in any one in claim 1-4, is characterized in that,

The neutral ground form of No. 1, No. 2 transformer is direct ground connection; One group of lightning arrester is installed respectively in the high-pressure side of No. 1, No. 2 transformer.

6. PT2 type power distribution station as claimed in claim 5, is characterized in that,

The low-pressure side of No. 1 transformer connects mono-section of bus of 0.4kV by a distribution transformation switch, in each outlet of this section of bus, is respectively equipped with outlet switch;

The low-pressure side of No. 2 transformers connects bis-sections of buses of 0.4kV by another distribution transformation switch, in each outlet of these two sections of buses, is respectively equipped with outlet switch;

Two group capacitors are connected to respectively described one section of bus and two sections of buses by corresponding capacitor switch; Described distribution transformation switch, outlet switch, capacitor switch are vacuum circuit-breakers.

7. PT2 type power distribution station as claimed in claim 6, is characterized in that,

Two groups of high-voltage boards that SF6 load plug-in strip is set are respectively positioned at hyperbaric chamber;

The low voltage incoming line cabinet of two relative set distribution transformation switchs, the low-pressure line-outgoing cabinet of six relative set outlet switchs, two capacitor panels, a low pressure segmentation cabinet that block switch is set are positioned at low-pressure chamber;

No. 1, No. 2 transformers, by corresponding line cable, access respectively the high-voltage board in hyperbaric chamber, and by the low voltage incoming line cabinet of low pressure copper busbar access low-pressure chamber.

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