KR0185242B1 - Spot network power receiving and transforming apparatus - Google Patents

Abstract

In the case of power supply interruption in one of the distribution lines, a spot-network distribution system that is operable without interruption such as instantaneous power supply interruption, load limiting, etc. is disclosed. The spot-network system includes two network units each connected to two different distribution lines, and two power circuit breakers provided in each of the network units, one of the power circuit breakers in each of the network units. It is connected to the same distribution line used as a spare distribution line. By means of the spot-network system, the power receiving line disconnects the receiving units of the network unit in the event of a power interruption in one of the normally used distribution lines detected by each one of the two receiving voltage detectors provided in each network unit. By using it, it switches to a spare distribution line.

Description

A-SPOT-NETWORK DISTRIB UTION SYSTEM AND A OPERATION METHOD THEREOF

1 is a single-line diagram showing one embodiment of a spot-network distribution system according to the present invention.

2 is a disconnected diagram showing another embodiment of a spot-network distribution system according to the present invention.

3 is a diagram showing the change of operating states of the main components of the spot-network according to the present invention when power supply interruption occurs in a commercial distribution line 1A.

4 is a disconnected diagram showing the configuration of a conventional spot-network distribution system.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spot-network distribution system, and more particularly, to a spot-network distribution system of a high-rise building or a factory requiring high load demand and stable power supply.

Recently, the three-dimensional use of land and high-rise buildings has become more common. In high-rise buildings, the distribution of electrical loads in the vertical direction is not only large, but also requires a large load demand, and many important electric installations are installed. Therefore, there is a strong demand for an improvement in the reliability or stability of the power supply source. In addition, these electrical installations are often installed in dense construction areas and the floor space occupied by the installation is required to be as small as possible. Therefore, a spot-network distribution system with high supply reliability is most suitable for a space requiring a large load demand such as a building or a factory. Spot-network systems are provided with a circuit breaker at the top of the network transformer and a circuit protection circuit breaker at the bottom of the network transformer where the outputs at the load side are connected to the network busbar (abbreviated as busbar). It is a system for receiving power of 22kv or 33kv from a substation through a plurality of distribution lines by two to four spot-network units that distribute power to load demand facilities by several transmission lines connected to a bar. The prior art regarding a spot-network power distribution system is disclosed in Japanese Patent Application Laid-Open No. 1988-198524. In the conventional spot network distribution system, the three spot-network unit method is applied. However, this method is expensive because it requires three network transformers for high voltage and also requires a lot of floor space occupied by the power distribution equipment.

In order to avoid the above problems, as shown in FIG. 4, a spot-network distribution system applying a two spot-network unit method provided with two spot-network units has been invented and used. Each spot-network unit (also briefly referred to as a network unit) is provided with a power receiving breaker 22, a power receiving fuse 23, a transformer 25 and a circuit breaker 26, and a commercial distribution line 21A and a spare distribution line ( Receive power from one of 21B). When the power supply is stopped at the commercial distribution line 21A, the electric power distribution line is switched from the commercial distribution line 21A to the spare distribution line 21B. In addition, a single network distribution system employing a two-spot-network unit method in which a power receiving breaker is replaced with a fuse is required and used in many places.

However, in the conventional spot-network power distribution system employing the two-network unit method, all power supply interruptions can be prevented, but in the case of power interruption of one circuit, one transformer becomes incapable of power distribution and sometimes causes a load limit. . Then, all power supply interruptions are caused by power supply interruption in commercial power distribution lines in the single spot-network power distribution system applying the two-network unit method. Naturally, the distribution of load demand becomes available again after switching the receiving breaker to the preliminary distribution line side. For this reason, in each of the conventional spot-network distribution systems employing the two-network unit method or the single spot-network distribution systems employing the two-circuit method, some obstacles to distribution according to the load demand are caused.

The present invention has been achieved in view of the above problems, and inexpensive spot-network which can operate without interruption such as instantaneous power supply interruption, load limiting, etc. in the event of power supply interruption in one of the distribution lines. It is an object to provide a power distribution system.

The spot-network power distribution system according to the present invention includes a plurality of network units each having first and second power receiver detectors, each of which receives power from power distribution lines connected to the first power receiver, and a power distribution line connected to the first power receiver. And switching means for switching the power receiving line from the distribution line connected to the first receiving breaker to the distribution line connected to the second receiving breaker when the power supply interruption occurs and is detected by the receiving voltage detector.

In a preferred example of the spot-network distribution system, two network units are provided, and the second receiving breaker of each network unit is connected to the same third distribution line provided as a spare line.

In the spot-network distribution system having such a structure as described above, the power breaker of the network unit connected to the distribution line where the power supply interruption occurs is disconnected, but power is distributed by the remaining network unit or units. Then, after the power circuit breaker is switched from the first power circuit breaker connected to the distribution line where the power supply is interrupted to the second power circuit breaker connected to the spare distribution line, all the network units are changed to the operation state again.

By the above operations of the spot-network power distribution system according to the present invention, even in the case of power failure in one of the power distribution lines, the remaining network unit or units are overloaded only for a short time and such as instantaneous power supply interruption, load limiting, etc. The power can be distributed to the load according to demand without causing an obstacle.

In the following, the description of the invention is explained based on the embodiments with reference to the drawings.

In FIG. 1, the spot-network power distribution system having the network units 2A and 2B according to the present invention is shown by the figure (single diagram). Each of the network units 2A and 2B in the spot-network distribution system is connected to one of the pairs of distribution lines 1A, 1C and 1B, 1C for the spot-network power supplies, and receives power therefrom. Two network units are then connected to the busbars (referred to only as busbars) for the spot-network 12 to distribute power to each load demand facility.

The spot-network power supply distribution lines 1A and 1B are used as commercial ships (referred to only as distribution lines) and the spot-network power supply distribution line 1C is used as a reserve line.

Each network unit 2A and 2B includes two power receiver breakers 3A and 3B, a network transformer 4, a protective fuse 5 and a circuit protection circuit breaker, and supplies power to the busbar 12.

A voltage detector 9A, such as an instrumentation transformer, and a current detector 8, such as an instrumentation current transformer, are provided above the circuit protection circuit breaker 6, and the voltage detector 9B of the circuit protection circuit breaker 6 is provided. It is provided at the lower side, respectively, and these are connected to the network relay 10.

The network relay 10 includes a reverse power tripping member and a differential voltage reclosing member.

The reverse power tripping member opens the network relay 10 by detecting a reverse current flowing through the bus bar 12 to the network transformer 4. In the differential voltage reclosing member, the voltage detected by the voltage detector 9A is higher than the voltage detected by the detection voltage 9B, and the phase detected by the voltage detector 9A is detected by the voltage detector 9B. The network relay 10 is closed by detecting a closed state preceding the detected phase.

The members are connected to the circuit protection circuit breaker 6 via active circuits that open and close the circuit protection circuit breaker 6.

Receiving voltage detectors 7A and 7B are provided above the receiving breakers 3A and 3B and monitor the receiving states at the distribution lines. Then, the outputs of the power receiving voltage detectors are output into the control circuit 11, which controls the power circuit breakers 3A and 3B and the circuit protection circuit breaker 6 based on the information on the power reception states monitored among the distribution lines. It automatically switches power distribution lines by outputting control signals.

The control circuit 11 also provides a locking circuit for the differential voltage reclosing operation in which the closing operation of the circuit protection circuit breaker 6 is temporarily stopped until the switching of the power receiving breakers 3A and 3B is completed. Include.

The operation of the spot-network distribution system having the above structure in the event of a power supply interruption in one distribution line is described next.

In the case where the power supply interruption occurs for some reason in the distribution line 1A while the network units 2A and 2B receive power from the distribution lines 1A and 1B, respectively, the reverse current flows from the distribution line 1B to the distribution line 1A. ) Flows through network 2B and busbar 12, resulting in reverse power.

The network relay 10 detects reverse power and opens the circuit protection circuit breaker 10. Then, when the distribution line 1C is in a steady state, the power receiving voltage detector 7A detects a zero voltage at the power distribution line 1A, and the power receiving voltage detector 7B detects a rated voltage.

Based on the above information, the control circuit 11 has a state in which the voltage detector indicates zero voltage and the power receiving breaker 3A is open (1), and the voltage detector 7B is rated at the preliminary distribution line 1C. Instructs and confirms the state (2) in which the power circuit breaker 3B is closed, and the state (3) in which the circuit protection circuit breaker 3A is opened, and instructs to open the power circuit breaker 3A and closes the power circuit breaker 3B. Send the command.

After the operations by the control circuit 11, the network unit 2A encounters the differential voltage re-closing state (when the load is heavy and the network unit 2A is in the live state) the spare power distribution line 1C The circuit breaker 6 is changed to the power receiving state and a closing command is given to the circuit protection circuit breaker 6 by the network relay 10. After that, both network units become operational.

As a result, the network transformer 4 of the network unit falls into an overload state only for a short time and can continuously operate the load receiving facility without giving any damage to the facility. The breaker breakers only acquire the ability to stop or flow the excitation current of the network transformer and the breaker breakers 3A and 3A with the circuit protection breaker 6 opened by reverse power tripping obtained by the network. Since 3B) is switched, it is possible to reduce the production cost of the spot-network distribution system by eliminating the need for such load disconnection switching, which is required for a single spot-network distribution system having two network units.

Then, when the distribution line 1A returns to the above state of the spot-network distribution system, the power distribution line is switched to the original commercial distribution lines. In the switching operation of returning to the original distribution line, the control circuit 11 has a state (1) in which the power receiving voltage detector 7A indicates a rated voltage and the power receiving breaker 3A is opened, and the network unit 2B is in a live state. (This state needs to prevent all power supply interruptions), i.e., in the network unit 2B, the (receiver voltage detector) 7A indicates the rated voltage, the breaker circuit breaker 3A is closed, and the circuit protection breaker. (6) is opened), or (the power receiving voltage detector 7B indicates the rated voltage and the power receiving circuit breaker 3B is closed and the circuit protection circuit breaker 6 is closed). Thereafter, the control circuit 11 of the network unit 2A sends an open command to stop the closing operation of the circuit protection circuit breaker 6, sends an open command to the power receiving breaker 3B, and closes the command to the power receiving breaker 3A. Send it.

After the power receiving breaker 3A is closed, the closing operation of the circuit protection breaker 6 is canceled. In the case of the differential voltage re-closing state, the circuit protection circuit breaker 6 is closed by the network relay 10 and the network unit 2A is in the original power receiving state.

Now, the above functions of the control circuit 11 can be easily realized using a computer.

In FIG. 2, a disconnection diagram with a simplified structure of the embodiment referred to by FIG. 1 is shown. In this embodiment, each of the network units 2A and 2B is connected to two distribution lines 1A and 1B via the power receiving breakers 3A and 3B of each network unit. In the network unit 2A, the distribution line 1A is used as the original distribution line connected to the power receiving breaker 3A, and the distribution line 1B is used as a spare distribution line connected to the power receiving breaker 3B, and in the network unit 2B. On the contrary. In addition, by operating the spot-network power distribution system as well as the embodiments described by FIG. 1, even if a power failure occurs in one of the two power distribution lines, the power supply is interrupted from only two power distribution lines. The spot-network power distribution system described above can be operated. However, the embodiment shown in FIG. 2 has advantages over the embodiment shown in FIG. 1 in terms of production cost, but the reliability is slightly lower than that of the embodiment in FIG.

FIG. 3 shows the spot-network distribution system shown in FIG. 1 when the power distribution line of the network unit is switched from the distribution line 1A to the spare distribution line 1C at the time of power supply interruption in the original distribution line 1A. It indicates the change of current, voltage or operating state of main parts. The next operating state change of the disconnectors and the circuit breaker in the network unit 2A is caused by the power supply interruption in the distribution line 1A.

That is, opening of the circuit protection circuit breaker 6

→ Opening the breaker breaker (3A)

→ Close the breaker (4B)

^ Close the circuit protection breaker (6).

While the above operating state is changed, the network unit 2B is changed to the overload state for a short time.

Another embodiment described below is effective in improving the safety of power reception by a spot-network distribution system.

In general, when the number of load demand equipment connected to a distribution line increases, the required current also increases, reducing the voltage of the distribution line. At this time, in this embodiment, the analog voltage values output from the power receiving voltage detectors 7A and 7B are input into the analog comparator provided in the control circuit 11 and compared with each other by the analog comparator. When the voltage of the other distribution line is higher than the voltage of the distribution line currently used for power reception in this network unit, the power distribution line is switched to the other distribution line by the same method as disclosed in the above embodiments.

Further, the hysteresis characteristic is combined with the function of the comparator to compare the output voltage values from the power receiving voltage detectors 7A and 7B in order to prevent the pumping phenomenon or unnecessary switching during distribution line switching.

In addition, when the power supply stage occurs in the same line when two network units 2A and 2B are connected to the same distribution line, in order to prevent the occurrence of all power supply interruptions, the network unit 2A is in a distribution line switching state. The distribution line switching is executed by confirming that no other network unit 2B is connected to the spare distribution line 1C.

This embodiment has the advantage that the load demand facility can be operated continuously without any obstacle in the case of power supply interruption of one distribution line, and the loads divided by the distribution lines are equal.

As described above, according to the present invention, it is possible to provide a spot network distribution system that can be operated without risk of instantaneous power supply interruption, load limiting, etc., even when power supply is interrupted in one of the distribution lines.

Claims (10)

A spot-network distribution system for supplying power from a plurality of distribution lines of power supplies to a bus bar of a spot-network distribution system via network units each having a circuit protection circuit breaker; A plurality of network units connected to the plurality of distribution lines; First and second receiving circuit breakers provided in respective network units and respectively connected to different lines of the plurality of distribution lines, and when the power supply is interrupted at the distribution lines connected to the first receiving circuit breaker, the first power receiving unit; And switching means for switching a power receiving line from the distribution line connected to the disconnector to the distribution line connected to the second receiving circuit breaker. 2. The switching circuit according to claim 1, wherein after the power supply recovery, switching the power receiving line from the distribution line connected to the second receiving circuit breaker, which was switched and used at the time of power supply interruption, to the distribution line connected to the first receiving circuit breaker. A spot-network distribution system, further comprising means. 3. The power distribution system of claim 1 or 2, wherein the network units are provided in two units, and each of the two network units detects a power distribution state at an upper distribution line connected to each of the first and second receiving breakers. Spot-network distribution system comprising two receiving voltage detector. 4. The spot-network distribution system according to claim 3, wherein the two second receiving breakers in the two network units are connected to the same spare distribution line. 5. The method of claim 4, wherein information about power distribution states of the power distribution line detected by the power receiving voltage detectors and respective states of opening and closing of the first and second power receiving circuit breakers and the circuit protection circuit breaker is obtained. Receiving instructions for switching the power supply line from the distribution line in which an abnormality occurs in one of the distribution lines to the normally operating distribution line, and after the power supply recovery, the switch that was switched and used in the event of a power supply interruption. And a control circuit in the network units for sending commands to the power receiving breaker and the circuit protection breaker to switch the power receiving line from the power distribution line connected to a second power circuit breaker to the power distribution line connected to the first power circuit breaker. Spot-network power distribution system. A spot-network distribution system for supplying power from a plurality of distribution lines of power supplies to a bus bar of a spot-network distribution system via network units each having a circuit protection circuit breaker; A plurality of network units connected to the plurality of distribution lines, first and second receiving breakers provided in the respective network units and connected to other lines of the plurality of distribution lines, respectively; Two receiving voltage detectors detecting power distribution states in the distribution line connected to the two receiving circuit breakers; and if abnormality is detected by the receiving voltage detectors in the distribution line connected to the first receiving circuit breaker, the first receiving circuit breaker And switching means for switching the power receiving line from the connected distribution line to the distribution line connected to the second receiving circuit breaker. 7. A spot-network distribution system according to claim 6, wherein said power distribution line is switched to said distribution line having a high voltage. 8. The method of claim 7, wherein information about the power wiring states of the power distribution line detected by the power receiving voltage detectors and the states of opening and closing of the first and second power receiving circuit breakers and the circuit protection circuit breaker is obtained. Receiving and switching commands for switching the power receiving line from the distribution line in which an abnormality occurs to an abnormal occurrence in one of the distribution lines to the normally operating distribution line, and after the return to normal from the distribution line used and switched in the abnormality. And a control circuit further sending instructions for switching the power receiving line to a power distribution line to the power receiving circuit breakers and the circuit protection circuit breaker. A method for switching the power receiving line from an abnormal distribution line to which a abnormality occurs, by using the spot-network distribution system according to claim 3 or 6; In the network unit connected to the abnormal distribution line, the receiving circuit breaker connected to the abnormal distribution line is closed, the voltage of another distribution line is normal, the receiving circuit breaker connected to the normal distribution line is opened, and the circuit protection circuit breaker is opened. Confirming; Opening the receiving breaker connected to the abnormal distribution line; And closing the circuit breaker connected to the normal distribution line and closing the circuit protection circuit breaker of the network unit in which the switching is performed. 8. A method for switching the power supply line from a distribution line that is switched and used at an abnormal occurrence to an abnormal but returned distribution line using the spot-network distribution system according to claim 3 or 7. In the network unit connected to the distribution line which was abnormal, confirming that the power receiving circuit breaker connected to the abnormal distribution line is opened, and that the voltage of the distribution line returns to normal; Confirming that the other network units are in a normal operating state, and opening the circuit protection circuit breaker of the network unit in which the switching is performed; Locking the opening operation of the circuit protection circuit breaker; opening the power receiving circuit breaker connected to the distribution line which is switched and used when an abnormality occurs; closing the power receiving circuit breaker connected to the distribution line which was abnormal but returned; and A switching method comprising the step of closing the circuit protection circuit breaker.