JPS6111041B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to an improved spot network power receiving facility applicable to crowded urban buildings.

In general, spot network power receiving equipment supplies power to customer loads from different power feed lines sent out from a power substation of a power company. Figure 1 shows the spot network power receiving equipment that receives power from such a substation.
a cable head 3 for terminating the cable on each primary side of the transformer 5;
A bus line is connected via a primary disconnector 4 that can switch only the excitation power source, and supplies power to each load via a protector fuse 6 and a protector disconnector 7 on the secondary side of each of these transformers 5. The network bus 8 is connected to the network bus 8. The network bus 8 is connected to the load in each direction within the building via a takeoff device that has load overload, overcurrent, and ground fault protection and measurement functions, which is composed of a takeoff fuse 10 and a takeoff shield 9, etc. and are configured to supply power to each load. In addition, the transformer 5 has an overload operation characteristic so that even if one of the power supply lines 2 stops, the other power supply lines can continue to supply power to the building load, and the value is 130% after 100% operation. A value of several hours or several times a year has been adopted to increase the reliability of power supply.

Here, the protector shield disconnector 7 is controlled to shut off and close by a network relay device 11 having the following functions, thereby enabling automatic operation of the power receiving equipment. That is, this network relay device 11 detects the current flowing in the opposite direction through the network protector/disconnector 7, disconnects the protector/disconnector 7, disconnects it from the faulty line, and connects it to another transformer. Reverse power disconnection function that enables power supply, protector When all disconnectors 7 are OFF, the primary disconnector 4 is turned on, and the transformer secondary detects that the transformer 5 is energized, and the protector is activated. It has a no-voltage closing function that automatically closes one of the shield disconnectors 7, and detects that the voltage on the power supply side of the protector shield disconnector 7 is higher than the voltage on the load side and is ahead of the phase. It has three functions: a differential voltage application function that turns on the protectors and disconnectors 7 one after another, and the protectors and disconnectors 7 are turned on and controlled by any one of these functions. On the other hand, in terms of voltage, the spot network power receiving equipment with such a configuration has a cable head 3, a primary disconnector 4,
A special high-voltage block consisting of a transformer 5 and a low-voltage block consisting of a protector fuse 6, a protector breaker 7, a network relay 11, a network bus 8, a take-off breaker 9, and a take-off fuse 10. It can be broadly classified. Here, even if the former special high voltage block is high voltage or low voltage, and the latter low voltage block is high voltage, it can be roughly divided into two blocks with the part corresponding to the transformer as the boundary, and this is the most commonly applied block. The case of special high pressure and low pressure blocks will be explained below as an example.

Furthermore, the low pressure block has protector fuse 6.
Protector fuse section 22 corresponding to
Protector connection section 2 that electrically connects protector fuse 6 and protector shield and disconnector 7
3. A protector shield section 24 corresponding to the protector shield disconnector 7; a network relay device section 2 corresponding to the network relay device;
5. A network bus connection section 26 that electrically connects the protector/disconnector 7 and the network bus, a network bus section 27 corresponding to the network bus 8, and a takeoff/disconnector 9 and a takeoff fuse 10. The take-off equipment section 28 can be subdivided into a take-off equipment section 28 consisting of, etc.

Therefore, when the spot network power receiving equipment is installed in a building as a closed switchboard, the blocks and sections described above are arranged in various combinations, but depending on the shape of the space in the building, the transformer 5
In the unlikely event of a short-circuit accident between the secondary terminal of the power supply substation 1 and the protector fuse 6, the operation of the overcurrent protection device within the power supply substation 1 will be prevented from affecting other consumers connected to the extension of the power supply line 2. For such purposes, a protector fuse section 22 is incorporated into the above-mentioned special high voltage block 21 to form one group, and a protector fuse section 24, a network relay section 25, a network bus connection section 26, and a network bus section 27 are assembled. , take-off sections 28 are combined to form another group, and a separate type is adopted in which the respective groups are arranged separately and the protector connection sections 23 are connected between them.

This separated type case is shown in FIG. That is, a panel consisting of a special high voltage section consisting of a cable head chamber 3, a primary disconnection chamber 4, and a transformer chamber 5, a group A consisting of a protector fuse box 6, a protector, a disconnection unit, and a network relay unit 25. A panel consisting of a take-off fuse unit 9, a take-off fuse unit 9, and a take-off fuse unit 10 are arranged side by side, and a network bus 8 is installed in the bus room.
It is arranged separately from group B, which accommodates a group B, and is connected therebetween by a protector connecting device, for example, a bus duct 23.

FIG. 3 shows these electrical connections in a three-dimensional single-line diagram so that they can be easily understood. The configuration of each part is the same as that in FIG. 2, so the explanation will be omitted. The above-mentioned power receiving equipment with a closed switchboard configuration that is arranged separately has the following disadvantages. That is, a plurality of protector connection bus ducts connecting each group are always required, corresponding to each of the plurality of power supply lines.

The rated current of the bus duct needs to be able to carry the overload current according to the overload characteristics of the transformer without any problem, and in reality, it is expected that the overload current will be carried for about 8 hours. The load current causes a temperature rise in the conductors forming the bus duct to reach a saturated state.

Therefore, when manufacturing a bus duct, the overload current value is designed as a rated value, which increases both the shape and cost of the bus duct.

The length of the bus duct is long, and there is a high risk of accidents due to defects in the tightening parts.

As a result, the number of man-hours required to route the bus ducts onto the building roof increases.

A lot of space is required because multiple bus ducts are routed around the ceiling of the building.

The length of the bus duct between each bank may differ depending on the separation arrangement situation, so usually,
There is a risk of overheating and destruction due to an imbalance in the current between each bank during a short circuit.

The present invention was made in order to solve the above-mentioned drawbacks, and it incorporates everything from the cable head that makes up the spot network power receiving equipment to the protector and disconnector into one group, and connects their load sides in common. By configuring the other groups with take-off equipment and network busbars, and by making each group into a closed switchboard configuration, the bus duct connecting between them is integrated, reducing the cost and construction work for bus ducts and bus duct routing. The purpose is to provide spot network power receiving equipment that reduces man-hours and space on the building.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 4 shows a three-dimensional single-line connection diagram in the case where the devices are separated into two groups, and one bus duct 30 between each group can function as a conventional spot network power receiving device. In other words, in a group A in which each bank includes a cable head 3, a primary disconnector 4, a transformer 5, a protector fuse 6, a protector and a disconnector 7, and each bank is arranged in a row, for example, a protector is installed on the ceiling. The load side of the disconnector 7 is connected to the network bus connection conductor 26.
A drawer section 31 for connecting to other groups is provided. Note that the portion including the network transformer 5, protector fuse 6, protector and disconnector 7 will be referred to as a network unit for convenience. On the other hand, other group B
Take-off switch 9, take-off fuse 1
0, etc., are configured in a row, and a network bus 8 is provided within the panel, and the load current is distributed equally to the take-off devices connected to the network bus 8 to the group A mentioned above. A drawer section 32 is provided. With this configuration, by connecting the drawer sections 31 and 32 with the bus duct 30, a spot network power receiving facility having the same overall functions as the conventional one can be constructed with one bus duct.

To explain this in FIG. 1, in a group in which a plurality of special high voltage sections 21, protector fuse sections 22, protector shield/breaker sections 24, and network relay sections 25 are arranged in rows, the load side of the protector shield/breaker 7 is This corresponds to connecting the take-off section 28 and the network bus section 27 in parallel, and connecting the group consisting of the take-off section 28 and the network bus section 27 with a connecting device having the same function as the network bus section 8.

The method of determining the rated current in the portion of the bus duct 30 configured in this way is generally based on the way that the transformer 5
130% overload operation occurs when any one of multiple banks stops. Therefore, we will now take an example of a 3-bank configuration and replace it with the conventional 1 in Fig. 3.
If the current flowing through the bank's bus duct 23 when the transformer is operating at 100% is 100, the current of the transformer is 130.
Since the value of % overload current was the rated current of the bus duct, the rated current of each bus duct was 130
Therefore, a total of 130 x 3 banks = 390 bus ducts were installed.

On the other hand, in the case of the configuration according to the present invention, the rated current required for the bus duct 30 in Fig. 4 is 100% of that of the transformer.
During operation, 100 x 3 banks = 300, and the transformer
At 130% operation, 130 x 2 banks = 260, so at most 300, which reduces the total current capacity by 30% compared to the conventional one, and can significantly reduce costs.

FIG. 6 is a diagram showing the board configuration of FIG. 4.

As mentioned above, in a configuration in which the conventional protector fuses and protector disconnectors were roughly divided into two groups between the protector disconnector and the network busbar, the following You can get an effect like this.

The number of bus ducts connecting two groups can be reduced from multiple to one, making it possible to reduce the space inside the building and free up more space for other purposes.

The total current capacity can be reduced and the cost of the bus duct can be reduced.

The construction costs associated with the above-mentioned bus duct routing can be reduced.

Even if the separation arrangement differs depending on the building conditions, the difference in impedance of the conductor from the transformer secondary to the network bus between each bank can be kept to a minimum, minimizing the occurrence of unbalanced current during normal or short circuits. This improves reliability against overheating and destruction.

The total length of the bus duct can be shortened, reducing the number of tightening points, which reduces the possibility of accidents and improves reliability.

The present invention is not limited to the above embodiments, and group B may be as shown in FIG. That is, the connecting conductor 33 may be provided, for example, on the ceiling, so that the current can be equally divided and distributed to the take-off device 28 drawn out from the network bus bar 8.
Further, although the transformer is illustrated as a dry type transformer, an oil-immersed type transformer can also be constructed in the same manner without changing the gist of the present invention.

As described above, by dividing the spot network power receiving device into two groups, the protector, the disconnector, and the network busbar, and arranging each separately, the disadvantages of the conventional method can be overcome, and the current capacity of the bus duct can be reduced. A network power receiving network with improved reliability against accidents and overheating in the ducts, which can reduce the number of ducts, create more effective space on the building roof, reduce construction costs, and contribute to reducing total costs. equipment can be provided.

[Brief explanation of drawings]

Figure 1 is a single-line connection diagram of a spot network power receiving device. Figure 2 is a three-dimensional configuration diagram showing a conventional spot network power receiving equipment. Figure 3 is a three-dimensional single line diagram showing a conventional spot network power receiving equipment. FIG. 5 is a three-dimensional single line diagram showing a spot network power receiving equipment according to the present invention; FIG. 5 is a three-dimensional single line diagram showing a modification of group B of the spot network power receiving equipment according to the present invention; FIG. 1 is a three-dimensional layout configuration diagram showing a spot network power receiving equipment devised by the present invention; FIG. A...1st group, B...2nd group, 5...Network transformer, 6...Protector fuse, 7...
Protector and disconnector, 26... Network bus connection conductor, 8... Network bus, 30... Connection device.

Claims (1)

[Claims] 1. Receive power from multiple power supply lines through network transformers, connect each transformer to a common network bus through protector fuses and protector disconnectors, and then connect the power to the common network bus through multiple take-off devices. In network power receiving equipment that supplies power to each load using a A first group in which load-side conductors of protectors and disconnectors are connected in common, and a second group in which the network bus bar and each take-off device are housed in a housing, and these first group The group and the second group are arranged separately, and the load-side conductor of the commonly connected protector or disconnector in the first group and the network bus bar of the second group are connected by one connecting device. In addition, network power receiving equipment in which the current capacity of this connecting device is set to be less than the sum of the above-mentioned transformers at 100% operation.