KR20090024035A - Current transformer changing method with extra transformer - Google Patents

Abstract

A method for replacing a pole transformer in an uninterruptible state is provided to reduce a device cost by excluding a phase change bypass device or an uninterruptible transformer. An additional hanger(11) is installed in an electric pole(13). An extra transformer(8) is hung on the hanger. The extra transformer is installed in a transformer rack of the hanger. The capacity of the extra transformer is larger than the capacity of the replacement object transformer. The extra transformer is connected in parallel with the replacement object transformer. The load of a low voltage wire(2) or a service wire is transferred to the extra transformer. The replacement object transformer is replaced in the uninterruptible state.

Description

Current transformer changing method with extra transformer

The present invention relates to the uninterrupted transformer (3) replacement work, uninterrupted replacement of the columnar transformer using the transformer (8) for construction, without using an expensive mobile type uninterruptible transformer device (7) in the conventional transformer uninterruptible method In addition, simply by installing one additional transformer 8 for the same construction in the same pole 13 relates to a distribution method that allows the uninterruptible replacement of the transformer (3).

In general, most of the pole-type transformer for distribution line converts electricity of extra-high voltage in the state that power is connected to each phase from the extra high voltage (earth voltage 13,200V, phase voltage 22,900V) wire, and then the power user side through low voltage distribution line (2) or lead wire. Supplied by. At this time, low voltage supply method using column transformer can be divided into 1-phase 2-wire 220V supply and 3-phase 4-wire 380 / 220V supply method. To supply voltage of 1-phase 2-wire 220V, 1 single-phase transformer, 3-phase To supply a 4-wire 380 / 220V voltage, three single-phase transformers are combined to form a sideband. When three transformers are installed on poles, the S-3 type three-phase hanger band 11 is attached to the poles 13 to mount the transformers. Although only one transformer can be installed by attaching a hanger band, the demand for a three-phase power source is increasing recently, and it is more economical to select a hanger band 11 in preparation for a change to a three-phase valve in the future. Recognizing this, it has become common to provide the S-3 type three-phase hanger band 11 in a single phase toilet location.

The shape of the three-phase hanger band is divided into an upper band and a lower band, and the transformer hangers for each phase are composed of three at an angle of about 90 °. Assuming that the transformer of is a B-phase transformer, the A-phase and C-phase transformers are installed on both sides with an angle of about 90 ° from the B-phase transformer, and the opposite side of the B-phase transformer is an empty space. It is supposed to remain.

Like the 3-phase hanger band, the shape of the hanger band for 1-phase valve is divided into upper and lower bands, but the transformer hanger is composed of only one. At that time, one A, B, or C phase transformer is installed at one position, and the remaining positions are left as empty spaces.

Figure 1 shows a connection method of a one-phase two-wire supply method of a general column transformer, Figure 2 shows a connection method of a three-phase four-wire supply method of the columnar transformer.

Referring to the drawings, the transformer connection method as shown in FIG. 1 connects the primary primary high voltage lead wire on one of the A phase, B phase and C phase lines of the special high voltage line 1, and outputs the secondary side of the transformer 3. Is connected to the power line and the ground line of the low voltage line (2), and the transformer connection method as shown in FIG. 2 uses the transformer primary high voltage lead wire for each phase in the A phase, B phase, and C phase lines of the special high voltage line (1). The grounding wires (4) of the three transformers (3) are jointly grounded at the bushing terminals and lowered alone, connected to the N-phase line of the low voltage line (2), and the secondary output of each transformer (3). Is connected to the power line of the low voltage line (2).

When replacing the column transformer for reasons such as aging or overload, the conventional replacement method is to operate the transformer to be replaced while causing a power failure to the consumer side by a diagonal operation and to move the uninterruptible transformer device to avoid the consumer power failure. (7) was used to bypass the target transformer (3) to replace the transformer (3) in an uninterruptible state. Recently, a bypass method by a phase shifter has been developed and applied in the field. have.

Replacing the transformer (3) by oblique work deteriorates the reliability of power supply from the electricity supplier's point of view, and consumes manpower according to pre-outage agreements and outage guidance from the electrician's point of view. And physical damage occurred. In order to solve the problem caused by the power failure, the bypass method by the mobile uninterruptible transformer device 7 has been developed, and FIG. 2 illustrates a transformer replacement method using the bypass method by the mobile uninterruptible transformer device 7. .

As shown in Fig. 2, each phase of the extra high voltage line 1 is connected to the primary side of the three transformers 3, respectively, and the secondary side of the transformer 3 is connected to each phase of the low voltage line 2, When the three-phase transformer is replaced using the uninterruptible transformer device 7, the high-voltage bypass line 5 is connected to the primary side of each of the high-voltage line 1, and the secondary-side is connected to the low-voltage line 2. After connecting the low voltage bypass line 6, voltage is applied to the uninterruptible transformer car 7 to form an uninterrupted bypass circuit in the three-phase columnar transformer. In this way, all three phases are replaced by the transformer while maintaining the uninterrupted state through the uninterruptible transformer device (7).

However, in the case of using the uninterruptible transformer car 7 in replacing the transformer 3

Although the problems caused by the power failure have been solved, the sheath of the extra high voltage wire (1) in the live state and the connection and disconnection of the extra high voltage bypass cable (5) in live state for the primary power supply of the mobile uninterruptible transformer device (7) Due to this complexity, there is a safety risk, and since the high-voltage bypass cable 5 is installed on the ground, there is a safety risk for the general public in the course of the work, and there is a problem that the wire damage occurs after the work. In order to replace the transformer with an uninterruptible power supply, the mobile uninterruptible transformer device (7) must be additionally installed. Therefore, the work is cumbersome in a narrow place such as an alley, obstructs the traffic of the vehicle, takes too much time and expense, and uses expensive equipment. The economic burden of equipping one company could not be ignored.

The bypass method of the recently developed phase shifter 15 is not applicable to a single phase in addition, and in the case of a three phase shift, the load of the transformer 3 to be replaced is transferred through the phase shifter 15. It is transferred to another phase transformer, and this method is applied when overloading a large-capacity transformer of three phases with different capacities, such as one three-phase four-seat 75KVA (equal equivalent) and two 30KVA (power only) units. Since there is a problem in that a load exceeding an overload capacity can be taken, an electric contractor can use an expensive phase shifter for this method, which is not publicly applicable to all transformer replacement sites. 15) may impair the efficiency of management, and it is not possible for the electricity supplier to actively use the construction method that may cause overload damage of other transformers during the construction process. It will silil. In addition, this method is easy to apply only when the secondary grounding cut-off line 4 of each three phase transformers 3 is a common ground and is not cut, but is cut down by itself. Since the grounding down line is being cut down in common, the practical application is difficult.

In order to alleviate the difficulty or cost burden of using a separate device such as the conventional mobile uninterruptible transformer device 7 or the phase shift bypass device 15, the transformer itself or a construction transformer to be replaced (8) ) In the same way with the transformer to be demolished and connected to the distribution line so that it is in parallel operation form, then replace the transformer to be uninterrupted.

As described in detail above, when replacing a transformer with an uninterrupted power, in the conventional uninterrupted method, a live vehicle, a crane for lowering a transformer, and an uninterruptible transformer device or a phase shift bypass device for securing an uninterruptible power are required. Uninterruptible transformers can be replaced by using a live vehicle, a crane, and one spare part of the transformer. Therefore, not only is the work simple, but also the transformer can be replaced in a narrow area such as an alley. There is no need to reduce the burden on equipment purchases.

The present invention does not use a separate device, such as the conventional mobile uninterruptible transformer device (7) or the phase shift bypass device (15), and replace the transformer by uninterrupted by using the transformer itself or construction transformer (8) to be installed and replaced The purpose of this is to apply the uninterrupted replacement method of the pole transformer using the construction transformer.

The present invention for achieving the above object is provided with a separate hanger (11) for hanging the construction transformer (8) in the electric pole 13 is installed a replacement target transformer (3), the transformer of this hanger 11 A construction transformer 8 having a capacity greater than or equal to that of the replacement target transformer 3 is installed on the hook 12 (or the redundant transformer hanger 12 of the hanger band that is already installed), thereby replacing the construction transformer 8 with the replacement target transformer 3 ) And transfer the load of the low voltage wire (2) or the lead wire supplied from the transformer to be replaced (3) to the construction transformer (8) and replace it while maintaining an uninterrupted state in which no power failure occurs at the consumer side.

If the remaining transformers in the three-phase transformer formed by combining three transformers are also sequentially replaced in this manner, the transformer 3 can be simply replaced without the primary side high-pressure bypass 5.

In the case of a one-phase inlet, the construction transformer 8 installed sideways at an angle of 90 ° with the existing transformer may be installed continuously, or the existing hanger band 11 is a three-phase S-3 type. In the case of a transformer, the construction transformer (8) itself is regarded as a new transformer and absorbs the load uninterrupted while being connected in parallel with the replacement transformer (3), and the removal of the replacement transformer may end all work processes, When it is difficult to use a construction transformer as a transformer for a distribution line, all work processes are terminated by replacing the transformer uninterrupted by using the parallel circuit of the construction transformer and then removing the construction transformer.

According to such a configuration, the transformer 3 can be replaced without using a separate device such as the conventional mobile uninterruptible transformer device 7 or the phase shift bypass device 15, which not only makes the operation simple, but also replaces the transformer. Reduction of construction cost and burden of equipment can be reduced, and it can be applied to narrow places.

The present invention is also a device required for the conventional primary-side high-pressure bypass, the high-pressure primary bypass cable (5), the extra-high voltage circuit breaker, the extra-high voltage transformer, the primary side and the secondary side of the complex device such as phase inspection device On the contrary, since the present invention only needs to be provided with a transformer for construction 8, the economic burden can be almost ignored from the perspective of the construction company.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a bypass connection diagram of a three-phase columnar transformer using a conventional uninterruptible transformer vehicle.

3 is a conventional transformer replacement method, by using an uninterruptible transformer car (7) to configure a high-voltage bypass (5) circuit on the primary side and a low-pressure bypass (6) circuit on the secondary side of the transformer (3) Was replacing

Figure 6b is a bypass connection diagram of a three-phase columnar transformer using an uninterruptible replacement of the columnar transformer using a construction transformer according to the present invention.

If the transformer is to be replaced in the three-phase, as shown in Figure 6b, by using the construction transformer 8, the primary 9 and the secondary 10 of the replacement transformer 3 in the same connection method When connected in parallel, the load is shared by the construction transformer (8), and when the replacement target transformer (3) is removed, the full load of the demolition target transformer (3) is transferred to the construction transformer (8) which was operated in parallel to dismantle the transformer by uninterruption. When the replacement transformer is connected to the primary (9) and the secondary (10) in the same connection method as the construction transformer (3), a part of the load transferred to the construction transformer (8) is transferred, When the secondary 10 and the primary lead 9 of the construction transformer (8) are separated from the track, the load on the construction transformer (8) is replaced with the newly installed transformer, and the load is transferred to complete the transformer construction of the phase. will be. When additional transformers in other phases are replaced at the corresponding side, the sequential work can be performed smoothly.

If you want to replace the transformer in the one-phase, as shown in Figure 5b, using the transformer for construction 8, the primary 9 and the secondary 10 of the replacement target transformer 3 in the same connection method In parallel, the load is shared by the construction transformer (8), and the construction transformer (8) which was operated in parallel when the secondary 10, the primary lead wire (9) and the transformer (3) itself of the replacement target transformer (3) were removed. The full load of the demolition target transformer (3) is transferred to) so that the transformer (3) can be dismantled by uninterruption, and the newly-installed transformer can also be replaced by the same wiring method as the construction transformer (8). When the car 10 is connected in parallel, part of the load transferred to the construction transformer 8 is transferred to the new transformer, and the secondary 10 and the primary lead wire 9 of the construction transformer 8 and the construction transformer are lined up. When dismantled from the transformer, the load on the construction transformer (8) is replaced with a new transformer. As a result, transformer construction of the corresponding side is completed uninterrupted.

If a single-sided transformer is installed at a 90 ° angle of the demolition target transformer (3) at a site where a new transformer can be operated, a separate hanger band (11) may be installed, or the hanger band (11) may be a three-phase valve. If a substitute S-3 is installed, the newly installed transformers are installed in parallel at a 90 ° angle of the demolished transformer 3, and the work is completed by simply removing the demolished transformer 3.

Of course, for other transformers that do not work in this whole process, by insulating protection of the transformer and COS as well as the primary and secondary leads, it is possible to ensure sufficient safety and ease of operation.

1 is a diagram illustrating the wiring and construction of a transformer in a one-phase two-wire transformer.

2 is a diagram illustrating the wiring and construction of a transformer in a three-phase four-wire toilet.

3 is a connection diagram of a transformer uninterruptible replacement operation using an uninterruptible transformer device

Figure 4 is a work connection diagram using a phase shift bypass device

Figure 5a is a plan diagram and circuit diagram before the operation of the single phase toilet

5B is a plan view and a circuit diagram of the transformer replacement operation of the one-phase valve according to the present invention.

Figure 6a is a plan connection diagram and circuit diagram before the three-phase toilet operation

6B is a plan view and a circuit diagram of a three-phase transformer transformer replacement work according to the present invention.

[Explanation of symbols on the main parts of the drawings]

1: High voltage line

2: low voltage line

3: transformer

4: ground cut line

5: uninterruptible transformer unit extra high voltage bypass cable

6: uninterruptible transformer unit low voltage bypass cable

7: uninterruptible transformer device

8: transformer for construction

9: construction transformer primary impression line

10: secondary transformer for construction transformer

11: hanger band

12: hanger band transformer hanger

13: Jeonju

14: COS for pole transformer

15: phase shift bypass device

Claims (2)

To replace the transformer in the three-phase four-wire 380 / 220V supply or the one-phase two-wire 220V supply, install a transformer for the same specification as the general transformer used in the distribution line in the electric pole. After the primary and secondary lead wires are connected in the same way and connected in parallel, the transformer to be demolished is uninterrupted and the new transformer is newly connected with the same wiring as the demolished transformer and connected in parallel with the construction transformer. By dismantling the power supply in the original form, it is possible to perform transformer replacement work in the uninterrupted state. It is the same as a general transformer used in distribution lines to replace transformers at the site where a new single-phase transformer can be installed and operated at a position of 90 ° angle difference with a demolition target of 1-phase 2-wire 220V supply method. Uninterrupted state by installing the construction transformer of the specification on the pole and connecting the demolition transformer and the primary and secondary lead wires in the same way and connecting them in parallel, and then dismantling the secondary, primary lead wire and the transformer itself. Power distribution method for uninterruptible replacement of the columnar transformer, characterized in that the transformer replacement construction in

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