KR100517803B1 - A switching system for underground electric power line to be exchanged high voltage transformer without interruption of electric power on the existing underground electric power line - Google Patents

Abstract

The present invention is to cut off the high voltage power between the elbow insert (insert terminal) and the elbow of the transformer so that the transformer can be easily replaced without a power failure in the event of a failure of the existing underground line supplying home and industrial power. The present invention relates to a switching system capable of simultaneously switching three-phase or single-phase for underground lines with a switch means for attaching a switch so as to replace the transformer on the underground line so that work can be performed without power failure. In the home and industrial power supply, the transformer is used as a means of dropping the voltage to supply the low voltage of 220 / 380V at the high voltage of 22.9kV, which is supplied through the power line from the power plant. If a fault occurs in the transformer, it should be replaced with a transformer that operates normally.When replacing a transformer of a ground line, it is performed by uninterrupted work using an uninterruptible transformer replacement vehicle. The present invention relates to a underground line switching system that enables uninterruptible operation because it causes inconvenient power failure due to the inevitable power failure.

[Index]

SF ₆ Gas Switchgear, Underground Transformer, Uninterruptible Transformer Replacement

Description

A switching system for underground electric power line to be exchanged high voltage transformer without interruption of electric power on the existing underground electric power line}

The present invention is to cut off the high voltage power between the elbow insert (insert terminal) and the elbow of the transformer so that the transformer can be easily replaced without a power failure in the event of a failure of the existing underground line supplying home and industrial power. The present invention relates to a switching system for underground lines with a switch means attached to the switchgear to enable operation without a power failure when replacing a transformer on the underground line.

Looking at the existing underground line in detail, the transformer as a means of dropping the voltage to supply a low voltage of 220 / 380V for the home and industrial at a special high voltage of 22.9kV supplied from the power plant through the transmission line in the home and industrial power supply If a transformer (aging) occurs due to aging or overload of the transformer, it should be replaced with a transformer that operates normally.When replacing a transformer on the ground line, it is performed by uninterrupted work using an uninterruptible transformer replacement vehicle. In the case of the underground line, the transformer between the switchgear and the switchgear is blacked out and then replaced with a transformer that operates normally. In performing these operations, power outages of large apartment complexes or industrial complexes are inevitable, which causes considerable inconvenience or economic loss to ordinary homes and businesses.

The technical problem to be achieved by the present invention is to elevate the special high-pressure side elbow of the transformer of the existing underground line in order to prevent the occurrence of inconvenience or economic loss of a number of homes or businesses due to the power failure during the replacement time of the transformer on the existing underground line A switch is provided between the insert (insertion terminal) and the elbow to switch off the high voltage power in order to open and close the power switch between the transformer and the switch on the load side in order to enable uninterrupted operation when replacing transformers on interconnected underground lines. The special high voltage cut-off switch is installed between the elbow insert (insertion terminal) of the underground line transformer and the elbow.

The present invention provides a special high pressure between the elbow insert (insert terminal) and the elbow on the special high pressure side of the transformer so that the transformer can be easily replaced without a power failure in the event of the failure of the existing underground line supplying home and industrial power. The present invention relates to a underground line switching system with a switch means attached to a switchgear to cut off the power supply so that work can be performed without a power failure when replacing a transformer on the underground line. There are various kinds of power cutoffs for the uninterruptible work as described above. Specifically, 1) Oil Circuit Breaker (OCB) has many disadvantages in terms of breaking performance and maintenance compared to other types of breakers, but it is inexpensive and has a merit that it can operate in a wide voltage range. It is widely used, but it is a disadvantage of fire and heavy because of using oil. 2) Vaccum Circuit Breaker (VCB) has very high dielectric strength and reduces the type of breaker. Since the contactor is isolated from the outside air, there is no risk of fire caused by the arc. It has the advantages of small size / light weight, simple structure, and easy maintenance, but it has the disadvantage of generating high surge voltage during operation. 3) Air Blast Circuit Breaker (ABBC) is designed to extinguish arcs generated by the contactor falling off with powerful compressed air (10-30kg). It has a certain effective capacity and has a low risk of fire, excellent blocking ability, and easy maintenance, but requires additional equipment such as a compressor for compressed air, and is widely used as a large-capacity circuit breaker. Used a lot in 4) Air Circuit Breaker (ACB) is a breaker that has an extinguishing method by natural appeal as the contactor drops when opening in natural air. It is often used as an AC voltage or DC breaker. When used as a DC circuit breaker, it is called a high-speed circuit breaker that has a short opening and closing time and a current-limiting action when breaking a short circuit current. Wiring breakers are miniaturized by inserting a device into a molded insulator, called a no-fuse breaker or MCCB (Molded Case Circuit Breaker). 5) Magnetic Blast Circuit Breaker (MBB) provides magnetic field at right angles to the arc, pushing the arc into the arc chamber, increasing the arc voltage, and cooling it to extinguish the arc. It is widely used in low voltage circuits ranging from 3.3 to 6.6 kV. Since there is no fear of fire and no insulation is used, there is no deterioration and maintenance is simple, but it is not suitable at high voltage in terms of extinguishing capacity. 6) Gas Circuit Breaker (GCB) Instead of air, compressed gas of SF ₆ (sulfur hexafluoride), which is an inert gas with excellent dielectric strength and extinguishing ability, is used. There are two types of gas circuit breakers: double gas pressure and single gas pressure in closed cycles, in which SF ₆ gas is blown from a high gas cylinder of 12-15 kg / cm 2 · g to a low gas system of approximately 2 kg / cm 2 · g. . It has few maintenance checks, good blocking performance and low noise. The price is high and the installation area is large, so it is mostly used as a high voltage circuit breaker. Among the various circuit breakers described above, the SF ₆ gas circuit breaker is excellent for breaking off and extinguishing power of the high voltage line, which is suitable for cutting off the power of the high voltage side of the transformer (22.9 kV). Although it is economical and has a disadvantage of being a little bulky, it is possible to select and use an appropriate capacity according to the size of the power to be cut off or to design accordingly according to the use.

Looking at the power supply process in connection with the present invention, in order to supply a low-voltage power supply of 220 / 380V of home and industrial power from 22.9kV extra high voltage power supplied from power plants through power transmission lines at home and industrial power supply The transformer is used as a means of dropping the voltage, and the transformer has an abnormality (failure) due to aging and overload. In this case, the transformer must be replaced with a normally operating transformer. Transformer replacement work is performed uninterrupted by general uninterrupted work using replacement vehicle, but in case of underground line, work is done by using switchgear installed at regular intervals. This causes the transformer to operate normally. The task of replacing the transformer has been made. As shown in Fig. 1, in the present underground line, circuit breakers for opening and closing the high-voltage distribution line are located between several transformers (3 to 5), and when the transformer is replaced, all the switches installed at both ends are opened and closed. Transformers located between the switchgear are blackouts, and temporary blackouts are inevitable in large apartment complexes or complexes powered by these transformers. However, as shown in Fig. 2, the switch is connected between the elbow insert (insertion terminal) of the high voltage terminal side of the existing transformer and the elbow to cut off the high voltage power, and then the switch attached when replacing the transformer on the underground line is sequentially Opening and closing allows work without a power outage. In order to achieve a specific configuration for achieving the above object a) Elbow insert installed in the existing transformer and the extra high voltage switchgear structure to the elbow that can be inserted into the elbow insert of the existing transformer and other high voltage circuit breaker 4 and a special high pressure circuit breaker which is directly coupled to the structure opposite to the elbow in the structure and the other side is formed of a structure that can be combined with the existing elbow, (c) the feature Formed with a structure that can be directly coupled to the high-voltage circuit breaker, and on the other side has a structure having an elbow insert that can be combined with the elbow of the existing transformer, and (d) attached to the left or right side of the special high voltage circuit breaker, three-phase or single-phase A switch (43 in Fig. 4) for cutting off the high voltage power and (e) the elbow insert are provided. The switch according to the present invention will mainly be described in the case of SF ₆ gas circuit breaker excellent in the ability to simultaneously cut off the special high-pressure three-phase or single-phase power supply among the various switches. Switching of the SF ₆ gas circuit breaker is accomplished by mechanical means (43 in FIG. 4). When one transformer (# 2 in FIG. 5) of the underground lines according to the present invention is to be replaced with a new transformer, a) after loop operation of the 22.9 kV distribution line, b) transformer # 2 (4) turn off the switch 4 of FIG. 5 (a), c) turn off the switch 5 of transformer # 3 (see FIG. 5 (a)), and d) The elbow attached to the switch 4 of (a) of FIG. 5 is separated from the transformer # 2 and connected to the junction (corresponding to (a) # 5 of FIG. 5), and e) the junction and the construction transformer through the elbow ( 5 (a) # 4), turn on switch 5 of transformer # 3 (see FIG. 5 (a)), f) and switch 8 of transformer # 4, The extra high voltage power is simultaneously supplied to transformer # 2 (Fig. 5 (a) # 2) and the construction transformer (Fig. 5 (a) # 4). g) Check whether the voltage of the low voltage side supplied from transformer # 2 (Fig. 5 (a) # 2) and the low voltage side supplied from transformer # 4 (Fig. 5 (a) # 4) is in phase, and h If the phases are the same, the low voltage side of transformer # 2 (Fig. 5 (a) # 2) and the low voltage side of construction transformer # 4 (Fig. 5 (a) # 4) are operated in parallel. i) After parallel operation, if the load supplied from transformer # 2 (Fig. 5 (a) # 2) is separated from the transformer, j) the full load supplied from transformer # 2 (Fig. 5 (a) # 2) is used for construction purposes. Transformer # 4 (converted to Fig. 5 (a) # 4) is supplied. This is completely separated from the load supplied from the transformer # 2 is supplied to the home or industrial complex (load) by the construction transformer # 4. Next, in order to separate the left side of the transformer # 2 from the power supply line, 1) turn off the switch 3 of the transformer # 2 (Fig. 5 (a) # 2), m) transformer # 1 (Fig. 5 (a Turn off the switch (2) of # 1) and disconnect the elbow connected to the switch (3) of transformer # 2. n) Remove transformer # 2 to be replaced. When the transformer replacement is completed, in order to connect the power supply line to the switch of the new transformer # 2 ', o) the elbow and the cable drawn out from the switch 2 of the transformer # 1 (Fig. 5 (a) # 1) are replaced. Connect to switch 3 'of transformer # 2' (Fig. 5 (b) # 2 '), and p) switch (2) and transformer # 2' of transformer # 1 (Fig. 5 (b) # 1). When switch 3 'is turned on, new transformer # 2' is pressed. Then connect the low voltage, which was disconnected from transformer # 2, which needs to be replaced. q) Disconnect the low voltage of construction transformer # 4 (Fig. 5 (b) # 4) and release the parallel load supply. To remove the junction, switch 8 of construction transformer # 4 (Fig. 5 (b) # 4) is turned off, and r) switch 5 of transformer # 3 (Fig. 5 (b) # 3) is turned off. After off, s) disconnect and remove junction # 5. t) Connect the elbow between transformer # 2 '(Fig. 5 (b) # 2') switch (4) 'and transformer # 3 (Fig. 5 (b) # 3) switch (5). u) Turning on switch 5 of transformer # 3 (Fig. 5 (b) # 3) and switch (4) 'of new transformer # 2' (Fig. 5 (b) # 2 '), the transformer to be replaced # In replacing 2 (FIG. 5 (a)) with a new transformer # 2 '(FIG. 5B), the operation of replacing the transformer uninterrupted is completed. The 22.9 kV distribution line terminates the loop operation and supplies all power to the newly replaced transformer. Through this process, the existing underground transformer is replaced without power failure. The relationship between the two sides of the high voltage circuit breaker of 22.9 kV is fixed / installed on one side of the high voltage circuit breaker according to the existing elbow insert when designing / manufacturing the high voltage circuit breaker, and on the other side to fit the internal space of the existing transformer. An elbow insert that accepts an existing elbow is attached and covered with an insulator to prevent accidents. The switch for cutting off the high voltage three-phase or single-phase power source allows to simultaneously switch the high voltage three-phase or single-phase power source. As such a device, it is preferable to use a SF ₆ gas circuit breaker capable of simultaneously opening and closing three-phase or single-phase high voltage power supply. The switching system as described above is designed and manufactured by installing / fabricating SF ₆ gas circuit breaker having an appropriate size and capacity for the existing transformer between the elbow insert and the elbow of the transformer used in the existing underground line. At the time of manufacture, when three phases or single phases are to be blocked or connected simultaneously inside the SF ₆ gas circuit breaker, each phase is connected by an insulator that can block extra-high pressure, and inside is filled with SF ₆ gas with excellent extinguishing ability. Therefore, the structure or size of installing a special high voltage switching system between the elbow insert and the elbow may be formed somewhat differently. In addition, the switch for disconnecting the three-phase or single-phase special high-voltage power supply (43 in Figure 4) is installed as a structure that can be moved mechanically located on the left or right side of the SF ₆ gas circuit breaker, the internal high pressure for the safety of the operator It is completely disconnected from the power supply.

EXAMPLE

The present invention provides a power switch that can cut off the high voltage power between the elbow insert (insert terminal) and the elbow of the existing transformer so that the transformer can be easily replaced without a power failure in the case of a transformer failure of the existing underground line supplying home and industrial power. The present invention relates to a switching system for underground lines, to which a switch means is attached to enable operation without a power failure when replacing a transformer on the underground line. Looking at the supply of power in relation to the present invention, in order to supply a low-voltage power supply of 220 / 380V of home and industrial power from the 22.9kV extra high voltage power supplied from the power plant through the transmission line at home and industrial power supply The transformer is used as a means of dropping the voltage, and the transformer has an abnormality (failure) due to aging and overload. In this case, the transformer must be replaced with a normally operating transformer. Transformer replacement work is performed uninterrupted by general uninterrupted work using replacement vehicle, but in case of underground line, work is done by using switchgear installed at regular intervals. This caused the transformer to operate normally It has made the task of replacing a transformer. As shown in Fig. 1, in the current underground line, the circuit breaker for opening and closing the high voltage distribution line is located between several transformers (3 to 5). In this case, a temporary power failure is inevitable in the large apartment complex or the entire industrial complex supplied by the transformer located between these switches. However, as shown in Fig. 2, a switch is provided between the elbow insert (insertion terminal) and the elbow at the high voltage terminal side of the existing transformer so as to cut off the high voltage power, thereby enabling work without a power failure when replacing the transformer on the underground line. It is to make it. In order to achieve a specific configuration for achieving the above object a) the elbow insert (41 of Figure 4) installed in the existing transformer and the elbow that can be inserted into the elbow insert of the existing transformer in a structure connecting the extra high pressure switch On the other side of the structure is formed to be directly coupled with the special high-pressure circuit breaker (42 in Fig. 4), and b) is directly coupled to the structure opposite to the elbow in the structure and the other side is formed as a structure capable of combining with the existing elbow SF ₆ gas Filled extra high voltage circuit breaker (44 in Fig. 4), and (c) is formed of a structure that can be directly coupled to the extra high voltage circuit breaker and the elbow insert (48 in Fig. 4) that can be combined with the elbow of the existing transformer on the other side 4, and (d) a switch (43 in FIG. 4) and (e) the elbow attached to the left or right side of the special high voltage circuit breaker to cut off a three-phase or single-phase special high voltage power supply. It offers a concert. The switch according to the present invention will mainly be described in the case of SF ₆ gas circuit breaker excellent in the ability to simultaneously cut off the special high-pressure three-phase or single-phase power supply among the various switches. Switching of the SF ₆ gas circuit breaker is accomplished by mechanical means (43 in FIG. 4). Referring to FIG. 5 with reference to the embodiment of the present invention as described above, when a transformer of one of the underground lines connected in parallel is replaced with a new transformer a) 22.9KV distribution line loop (LOOP) After operation, b) the switch 4 of transformer # 2 (see Fig. 5 (a)) is turned off, and c) the switch 5 of transformer # 3 (see Fig. 5 (a)) is turned off. d) The elbow attached to the switch 4 of transformer # 2 (see FIG. 5 (a)) is detached from transformer # 2 and connected to the junction (corresponding to FIG. 5 (a) # 5), and e ) Connect the junction and construction transformer (corresponding to (a) # 4 of FIG. 5) through the elbow, turn on switch (5) of transformer # 3 (see FIG. 5 (a)), f) and transformer # When the switch 8 of 4 is turned on, the high voltage power is simultaneously supplied to the transformer # 2 (Fig. 5 (a) # 2) and the construction transformer (Fig. 5 (a) # 4). g) Check whether the voltage of the low voltage side supplied from transformer # 2 (Fig. 5 (a) # 2) and the low voltage side supplied from transformer # 4 (Fig. 5 (a) # 4) is in phase, and h If the phases are the same, the low voltage side of transformer # 2 (Fig. 5 (a) # 2) and the low voltage side of transformer # 4 (Fig. 5 (a) # 4) are operated in parallel. i) After parallel operation, if the load supplied from transformer # 2 (Fig. 5 (a) # 2) is separated from the transformer, j) the full load supplied from transformer # 2 (Fig. 5 (a) # 2) is used for construction purposes. Transformer # 4 (converted to Fig. 5 (a) # 4) is supplied. This is completely separated from the load supplied from the transformer # 2 is supplied to the home or industrial complex (load) by the construction transformer # 4. Next, in order to separate the left side of transformer # 2 from the power supply line, l) turn off switch 3 of transformer # 2 (Fig. 5 (a) # 2), m) transformer # 1 (Fig. 5 (a) Turn off the switch (2) of # 1) and disconnect the elbow connected to the switch (3) of transformer # 2. n) Remove transformer # 2 to be replaced. When the transformer replacement is completed, in order to connect the power supply line to the switch of the new transformer # 2 ', o) the elbow and the cable drawn out from the switch 2 of the transformer # 1 (Fig. 5 (a) # 1) are replaced. Connect to switch 3 'of transformer # 2' (Fig. 5 (b) # 2 '), and p) switch (2) and transformer # 2' of transformer # 1 (Fig. 5 (b) # 1). When switch 3 'is turned on, new transformer # 2' is pressed. Then connect the low voltage, which was disconnected from transformer # 2 which needs to be replaced, to run in parallel. q) Remove the low pressure of the construction transformer # 4 (Fig. 5 (b) # 4) and release the parallel load supply. To remove the junction, switch 8 of construction transformer # 4 (Fig. 5 (b) # 4) is turned off, and r) switch 5 of transformer # 3 (Fig. 5 (b) # 3) is turned off. After off, s) disconnect and remove junction # 5. t) Connect the elbow between transformer # 2 '(Fig. 5 (b) # 2') switch (4) 'and transformer # 3 (Fig. 5 (b) # 3) switch (5). u) Turning on switch 5 of transformer # 3 (Fig. 5 (b) # 3) and switch (4) 'of transformer # 2' (Fig. 5 (b) # 2 '), the transformer to be replaced # 2. In replacing (a) of FIG. 5 with a new transformer # 2 '(FIG. 5 (b)), the operation of replacing the transformer uninterrupted is completed. The 22.9 kV distribution line terminates the loop operation and supplies all power to the newly replaced transformer. Through this process, the existing underground transformer is replaced without power failure. The relationship between the two sides of the high voltage circuit breaker of 22.9 kV is fixed / installed on one side of the high voltage circuit breaker according to the existing elbow insert when designing / manufacturing the high voltage circuit breaker, and on the other side to fit the internal space of the existing transformer. An elbow insert that accepts an existing elbow is attached and covered with an insulator to prevent accidents. The switch for cutting off the high voltage three-phase or single-phase power source allows to simultaneously switch the high voltage three-phase or single-phase power source. In addition, the switch for disconnecting the three-phase or single-phase special high-voltage power supply (43 in Figure 4) is installed as a structure that can be moved mechanically located on the left or right side of the SF ₆ gas circuit breaker, the internal high pressure for the safety of the operator It is completely disconnected from the power supply. As such a device, it is preferable to use a SF ₆ gas circuit breaker capable of simultaneously opening and closing three-phase or single-phase high voltage power supply. Among the terms described above in connection with the present invention, the terms breaker, switchgear and switching system are terms having almost the same meaning.

The effect of the present invention was to take the occurrence of inconvenience or economic loss of a number of homes and businesses by performing a temporary replacement of the transformer after replacing the transformer on the existing underground line, but the transformer of the existing underground line A switch is provided between the elbow insert (insertion terminal) of the high voltage side and the elbow, so that the high voltage power can be cut off. This can prevent the inconvenience or economic loss of many homes and businesses that are being powered by.

1 is a structure of the elbow for underground line with a switch function.

Figure 2 is a position of the extra-high pressure switch for underground lines according to the present invention.

Figure 3 is a side view (a) and front view (b) of a transformer for underground line with a switch according to the present invention.

Figure 4 is a structure of the elbow insert for underground tracks according to the present invention.

Figure 5 is an illustration of an embodiment of the present invention. (Before (a) and # 2 'replacement (b) of transformer # 2).

A description of the drawing numbers;

11, 15, 21, 25: switchgear, 27 three-phase special high voltage circuit breaker,

31,32: SF ₆ gas circuit breaker attached to the existing transformer,

# 1, # 2, # 3, # 4: transformers for underground lines, (# 2 ': new transformer, # 4: public transformer),

# 5: junction,

(1), (2), (3), (4), (5), (6), (7), (8): Elbow insert switch.

Claims (4)

In the switching system for opening and closing the high voltage side three-phase power supply for replacing the transformer installed in the underground line to the uninterruptible operation, An elbow that can be inserted into an elbow insert attached to a transformer installed in a underground line is installed on one side, and inside is filled with SF ₆ inert gas with excellent extinguishing capacity and insulation strength, and mechanically simultaneously supplies a 22.9 kV extra-high voltage three-phase power supply. A special high voltage circuit breaker having an elbow insert attached thereto so as to be switched on or off, and coupled to an elbow installed on the underground line on the other side; Attached to the left or right side of the extra high voltage circuit breaker to mechanically turn on or off the extra high voltage three-phase power supply installed inside the extra high voltage circuit breaker, and is coupled with a switching means installed inside the extra high voltage circuit breaker Switching system for uninterruptible work on underground tracks with switches designed to move down or up to mechanically disconnect or supply power. delete delete delete