JPH1132427A - Distribution system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability of supplying power by greatly shortening the failure lasting time or voltage drop time of a perfect circuit even if a failure occurs at any portion of a distribution system and to attempt to minimize the damage to the failed portion caused by arcs or to reduce pressure rise by the arc inside a distribution device. SOLUTION: Current detectors 11, 12a to 12c, 13a to 13c are arranged at the secondary side of a main switch 1 and branch switches 2a to 2c, 3a to 3c to feed each detected output to a failure determining and controlling device 42. When a failure such as a short circuit causes a current of a set value or more to flow in a given branch switch, this controlling device 42 immediately sends a contact parting command to the main switch 1 to break the current by making it part the contacts. Right after this, the contact parting command is sent to a branch switch directly above a portion, where a failure occurred to open its electric circuit by making it part the contacts. Then, the contacts of the main switch 1 are closed again. Switches having a short working response time (contact parting and closing times) are used as the main and branch switches.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power distribution system for receiving power and distributing power to load devices in the facility, for example, in a facility such as a building or a factory. The present invention relates to a power distribution system designed to improve the reliability of power supply by shortening the voltage drop time and reduce the degree of equipment damage due to an internal accident.

[0002]

2. Description of the Related Art FIGS. 7 (a) and 7 (b) show, for example, the first revised version of the guideline for high-voltage power receiving equipment published by Ohmsha.
It shows a simplified diagram of a part of the high-voltage power receiving equipment shown on page 54 and shows the operating characteristics of each switch in the figure.
This figure relates to a very general protection system for a high-voltage power receiving system. In FIG. 7A, 1 is a main switch closest to the power receiving end, and 2 is a bus 2 located below the main switch 1.
2 is a branch switch of one of several first-layer branches (not shown) connected to 2; 3 is some second layers of not-shown layers connected to a bus 23 located below the branch switch 2; One of the branch switches 4 is a branch switch of one of several third-layer branches (not shown) connected to a bus 24 located below the branch switch 3, and 11 , 12, 13, and 14 are current detectors installed near each switch. FIG. 7 (b) shows the operating characteristics of each switch, and shows that the operating time of each switch is set longer for a certain current value If as the higher order switch is. .

Next, the operation will be described. In FIG. 7A, when an accident occurs at the accident point A and an accident current If flows, the branching switch 4 cuts off the current at time t4 shown in FIG. 7B. At this time, the fault current also flows through the main switch 1, the branch switches 2 and 3, and the operation time is set as shown in FIG.
As shown in (b), since it is t4 or more, each switch does not operate. Next, a case where a short circuit accident or the like occurs at the accident point B will be described. In this case, the branch switches 3, 4
Since no fault current generally flows through the switch, each switch does not operate nor does it need to operate. This fault current is cut off by the branch switch 2, but in this power distribution system, the operation time of the branch switch 2 is set to t2, so that the switch can operate at time t4 or less. Nevertheless, the accident cannot be eliminated during the time t2.

[0004]

As described above, in the conventional power distribution system, the operation time of each switch is a so-called timed cooperative system in which the operation time of each switch is set in advance. In this case, the accident continues for a time t2, and for example, a system connected to a branch switch (not shown) other than the branch switch 2 connected to the bus 22 is
Voltage drop occurs during t2. In a conventional switch, for example, t2 is about 0.5 ms to 1 s, and the load equipment is seriously affected by such a voltage drop over time. FIG. 8 shows the influence of a typical device on the voltage drop.

Further, the equipment is damaged by the accident arc generated at the accident point A. The degree of the damage depends on the duration of the accident (time t4 in this case), and the degree of the damage is large. Further, such a power distribution system is generally housed and used in a housing, but if the accident point A is, for example, inside the housing, the pressure inside the housing increases due to the accident arc. The housing needs to have a structure having sufficient strength against the pressure increase. The present invention has been made in order to solve the above-described problems, and shortens the duration of an accident, shortens a voltage drop time, and minimizes damage to equipment and a rise in internal pressure of a housing. The purpose is to provide a power distribution system that can.

In the conventional switch, t4 shown in FIG. 7B is generally about 50 ms to 100 ms. Even in this case, considering the influence on the voltage drop of the equipment shown in FIG. give. SUMMARY OF THE INVENTION It is an object of the present invention to provide a power distribution system capable of minimizing the influence on a load in all accidents by shortening the opening time of a switch.

[0007]

According to a first aspect of the present invention, there is provided a power distribution system including at least one circuit distributed by a distribution conductor to a secondary side of a main switch having a primary side connected to a power receiving end. Or, a power distribution system in which at least one branch switch is disposed in at least one circuit formed and distributed in a plurality of stages, wherein the primary switch and the secondary side of the main switch and the at least one branch switch A plurality of current detectors provided on the side and detecting the magnitude of current flowing through the main switch and at least one branch switch; and at least one branch switch based on detection outputs of the plurality of current detectors. When a current equal to or more than the set value flows through the predetermined branch switch, the main switch is opened to cut off the current, and immediately thereafter, the predetermined branch switch is opened to open the electric circuit, and That The one in which a control means for controlling so as to closing the main switch again.

According to a second aspect of the present invention, in the power distribution system according to the first aspect of the present invention, the breaking capacity of the main switch is greater than the breaking capacity of the branch switch, and the control means controls a predetermined branch switch to switch the branch switch. The main switch is opened when a current of a magnitude that cannot be cut off by the switch flows.

According to a third aspect of the present invention, in the power distribution system according to the first aspect of the present invention, the control means comprises an accident determination control device, and detection outputs of the plurality of current detectors are supplied to the accident determination control device. The determination control device specifies one or a plurality of branch switches to be opened based on the detection outputs of the plurality of current detectors, and the current flowing through the specified branch switch is used for the specified branch switch. If it is within the shut-off capacity of the switch, it sends an opening command to the specified branch switch; otherwise, it sends an opening command to the main switch, and immediately after the specified branch switch. An opening command is sent to the switch, and then a closing command is sent to the main switch.

According to a fourth aspect of the present invention, in the power distribution system according to the first aspect of the present invention, the control means comprises a main switching controller and an accident determination control device, and the primary or secondary side of the main switching.
The detection output of the first current detector disposed on the secondary side is supplied to the main switching controller, and the plurality of second current detectors disposed on the primary side or the secondary side of at least one branch switch. Is output to an accident determination control device, and when a current equal to or greater than a set value is detected by the first current detector, the main switching controller instantaneously sends an opening command to the main switch to determine the accident. The control device specifies, based on the detection outputs of the plurality of second current detectors, a branch switch closest to the accident location and to be opened corresponding to the power receiving side of the accident location, and the identified branch switch. And then sends a closing command to the main switch.

According to a fifth aspect of the present invention, in the power distribution system according to the first or second aspect, the control means includes a plurality of individual determination controllers to which detection outputs of the plurality of current detectors are respectively supplied. , Each individual determination controller is connected to an individual determination controller corresponding to a switch located below the corresponding switch, and each individual determination controller is connected to a detection output of the connected current detector and a lower level. And determines the operation of the corresponding switch from the status signal of the lower switch supplied from the individual determination controller of the above and controls the switch, and is positioned above the corresponding switch. The state signal of the corresponding switch is supplied to the individual determination controller corresponding to the switch.

According to a sixth aspect of the present invention, in the power distribution system according to any one of the first to fifth aspects, the control means sends an opening command to the branch switch after sending the opening command to the main switch. At this time, after confirming that the current has been interrupted by the main switch, an opening command is sent to the branch switch.

A power distribution system according to a seventh aspect of the present invention is the power distribution system according to any one of the first to sixth aspects, further comprising opening detection means for detecting opening of at least one branch switch. When sending a closing command to the main switch after sending an opening command to the branch switch, after confirming that the circuit path is opened by opening the branch switch based on the detection output of the opening detection means, A closing command is sent to the device.

According to an eighth aspect of the present invention, in the power distribution system according to any one of the first to seventh aspects, the opening time of a part or all of the main switch and at least one branch switch is 10 ms or less. It is characterized by the following.

In a power distribution system according to a ninth aspect of the present invention, in any one of the first to eighth aspects, the closing time of a part or all of the main switch and at least one branch switch is 10 ms or less. It is characterized by the following.

According to a tenth aspect of the present invention, there is provided a power distribution system.
In the invention according to claim 8 or 9, a part or the whole of the main switch and at least one branch switch is constituted by a semiconductor switch element.

The power distribution system according to the invention of claim 11 is
In the invention according to claim 8 or 9, a part or the whole of the main switch and at least one branch switch is a high-speed response switch using an electromagnetic repulsion force in a switch mechanism. .

A power distribution system according to a twelfth aspect of the present invention
According to the eleventh aspect of the present invention, at least the opening or closing drive mechanism of the high-speed response switch is directly driven by a repulsive force between high-frequency currents supplied from an external power supply or eddy currents. It is assumed that.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a simplified single-line diagram of a power distribution system according to Embodiment 1 of the present invention. In the figure, reference numeral 1 denotes a main switch capable of responding at a high speed of about several ms in both closing and opening times using electromagnetic repulsion, and 2a to 2c branch off from a first bus 22 connected to the secondary side of the main switch 1. Is a branch switch capable of responding at a high speed of about several milliseconds in both closing and opening times using electromagnetic repulsion connected to the branch circuit. The branch switches 2a to 2c have a current interrupting capability higher than that of the main switch 1. It can be low.

Reference numerals 3a to 3c denote a high speed of about several milliseconds for both closing and opening times using electromagnetic repulsion connected to a branch circuit branched from the second bus bar 23 connected to the secondary side of the branch switch 2c. The branch switches 3a to 3c are capable of responding. The current breaking capability of the branch switches 3a to 3c is
Similarly to the above, it may be lower than the main switch 1. Also,
The main switch 1 and the branch switches 2a to 2c and 3a to 3c are, for example, high-speed switches that generate electromagnetic repulsion by the action of high-frequency currents supplied from an external power supply or eddy currents caused by the high-frequency currents. .

Reference numeral 11 denotes a current detector for detecting a current flowing through a circuit provided on the secondary side of the main switch 1, and 12a to 12a.
12c is a current detector installed on the secondary side of each of the branch switches 2a to 2c, and 13a to 13c is a current detector installed on the secondary side of each of the branch switches 3a to 3c. Note that these current detectors 11, 12a to 12c,
13a to 13c may be installed on the primary side of the corresponding switch.

Reference numeral 31 denotes a load connected to the branch switch 2a, and reference numeral 32 denotes a load connected to the branch switch 3c.
It should be noted that, in the figure, the line on the secondary side of the branch switch is indicated by a dotted line, indicating that a load, a bus or the like is connected. Reference numeral 42 denotes an accident determination control device, and each of the current detectors 11, 12a to 12c, and 13a to 13
c, information about current is sent by signal lines 51, 52a to 52c and 53a to 53c.
62a-62c, 63a-63c, the main switch 1,
An opening command or a closing command is sent to each of the branch switches 2a to 2c and 3a to 3c.

Next, the operation will be described. Fig. 2 (1)-
(4) is a timing chart for explaining the operation of the power distribution system shown in FIG. 1, assuming that a short-circuit accident has occurred at an accident point A in FIG. 1. FIG. 2 (1)
FIG. 1 shows a fault current waveform flowing to fault point A via a circuit including main switch 1, branch switch 2c, and branch switch 3c in FIG. 1 due to occurrence of a short circuit fault at fault point A. However, for simplicity, only one phase of a normal three-phase circuit is shown. 2 (2) is a waveform showing the open / closed state of the main switch 1, FIG. 2 (3) is a waveform showing the open / closed state of the branch switch 3c, and FIG. 2 (4) is a circuit voltage applied to the load 31 during normal operation. It is a waveform where the voltage is represented as 100%.

First, an accident occurs at time t1, and a large current shown in FIG. 2A flows through the circuit. This fault current is detected by the current detectors 11, 12c, 13c.
b, 13a and 13b are not detected. The detection outputs of these current detectors 11, 12c, and 13c are signal lines 51, 5
It is sent to the accident determination control device 42 by 2c and 53c. In the accident determination control device 42, the accident current (FIG. 2 (1)
At the time t2 when the current level exceeds the current level I1, for example.
It is determined that an accident has occurred, and an opening command is sent to the main switch 1 immediately. Since the main switch 1 is a high-speed response switch using electromagnetic repulsion, the contacts are separated at time t3 in a short opening time of time T1, and an arc is generated.

The accident determination control device 42 sends an opening command to the main switch 1 and simultaneously outputs the branch circuit current detectors 12a to 12a-1.
The accident location is specified by the information from 2c, 13a to 13c and the like. In this case, the current detectors 12c and 1c
Since the fault current is detected at 3c and no fault current is detected at the other current detectors, a fault has occurred below the current detector 13c. Determine that it needs to be released. After starting opening at time t3, the main switch 1 cuts off the current at the current zero point t4 of the fault current. The main switch 1 has a necessary interrupting capability for an accident current flowing due to an accident occurring at a lower level. Branch switches 2a to 2c,
In the case of 3a to 3c, even if an accident occurs at a lower level, the current is interrupted by the main switch 1, so that it is not necessary to have an interrupt current interrupting ability.

When it is confirmed by the current detectors 11, 12c and 13c that the main switch 1 has interrupted the fault current at time t4,
Immediately after the time T2, the accident determination control device 42 sends an opening command to the branch switch 3c to be opened next which has been specified in advance. Assuming that the time when the opening command is transmitted is t5, the contact point of the branch switch 3c is separated from the time at a time t6 after the opening time T3 of the branch switch 3c. Thereafter, at time t8 when the time T4 and the allowance time T5 required for the distance between the contacts of the branch switch 3c to be sufficient for the circuit voltage are added, the accident determination control device 42 issues a closing command to the main switch 1. Send out.

At time t6, the accident determination control device 42 detects that the branch switch 3c has been opened as instructed, for example, by an auxiliary contact as opening detection means of the branch switch 3c. The time of T4 + T5 is counted.
After the closing command is sent to the main switch 1, at time t9 after the closing time T6 of the main switch 1, the contacts of the main switch 1 are electrically connected, and the contacts other than the secondary side of the branch switch 3c are connected. Voltage returns to all circuits. Note that t7 is a time when the distance between the contacts of the branch switch 3c is sufficient for the circuit voltage.

The voltage applied to the load 31 during the series of operations will be described. The load 31 leads to a so-called healthy circuit. The voltage decreases to a voltage determined by the circuit constant until an accident occurs at time t1 and the main switch 1 interrupts the accident current at time t4. After the main switch 1 interrupts the current, the voltage of the load 31 becomes zero, and this state continues until the next time the main switch 1 closes.
Closes at time t9, the voltage is completely restored.

The voltage drop duration of the load 31 will be described. In high-speed response switches using electromagnetic repulsion,
For example, the opening time is about 1 ms, and the closing time is about 5 ms. If the opening time is about 1 ms, the fault current can be cut off in a half cycle of the commercial frequency, so that the time from the occurrence of the fault until the fault current is cut off is about 10 ms. The time T2 during which the accident determination control device 42 confirms the current interruption is almost zero, and the time T3 from when the opening command is sent to the branch switch 3c to when the opening is started is 1 ms when the branch switch 3c is opened, and the branch switch 3c Assuming that the time required to complete the opening is 5 ms, the allowance time T5 is 2 ms, and then the time T6 required to close the main switch 1 is 5 ms, the main switch 1 is closed again after an accident occurs. 23ms until extreme
About.

Next, consider the case where an accident has occurred at the accident point B in FIG. In this case, the accident determination control device 42 has caused an accident between the branch switch 2c and the branch switches 3a to 3c by the information sent from each current detector, and the switch to be opened is the branch switch 2c. Judge that there is. In this case, in the timing chart of FIG. 2, the operating switch is the branch switch 2c instead of the branch switch 3c. In this case as well, the time during which the voltage applied to the load 31 of the sound circuit falls is exactly the same as when the fault occurs at the fault point A.

As described above, according to the power distribution system shown in FIG.
There is an effect that an accident can be eliminated in a short time of 0 ms, and a voltage drop time of a load of a healthy circuit can be reduced to a short time of about 20 ms. According to the power distribution system shown in FIG. 1, when an accident occurs, the current is first cut off by opening the main switch 1, and then a predetermined branch switch is opened to open the electric circuit. In Although,
When the predetermined branch switch has an interrupting current interruption capability, the current may be cut off by opening only the predetermined branch switch without opening the main switch 1. .

Embodiment 2 FIG. FIG. 3 shows a configuration of a power distribution system according to Embodiment 2 of the present invention. 3, parts corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted. The output of the current detector 11 installed on the secondary side of the main switch 1 is input to the main switch controller 41, which further opens and closes the main switch 1 directly from the main switch controller 41. It is configured to send a pole command. The main switch controller 41 is connected to the signal line 5.
1. It is connected to the accident determination control device 42 by the control line 61, and can exchange current detector information and control signals. Other configurations of the power distribution system shown in FIG. 3 are the same as those of the power distribution system shown in FIG.

Next, the operation will be described. For example, when an accident occurs at the accident point A in FIG. 3, when the current detector 11 detects the accident current, the main switch controller 41 connected to the current detector 11 determines that the accident has occurred, An opening command is sent to the main switch 1 instantaneously. At the same time, it sends current information or information on sending an opening command to the main switch 1 to the accident determination control device 42. The operation after the interruption by the main switch 1 is the same as that of the power distribution system shown in FIG. 1 and the effect is the same as that of the power distribution system shown in FIG.

Embodiment 3 FIG. 4 shows a power distribution system according to Embodiment 3 of the present invention. In FIG. 4, portions corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted. In the present invention, the main switch 1, the branch switches 2a to 2c, and 3a to 3c are constituted by semiconductor switches using thyristor elements. Other configurations are shown in FIG.
The description is omitted because it is the same as the power distribution system shown in FIG.

The operation and effects of the power distribution system shown in FIG. 4 are the same as those of the power distribution system shown in FIG. 1, and therefore description thereof will be omitted. The power distribution system shown in FIG. 4 has thyristor elements connected in antiparallel. However, besides the thyristor element,
For example, a device using a semiconductor switch element such as a GTO, an IGBT, or a diode can obtain the same effect.

Embodiment 4 FIG. FIG. 5 shows a power distribution system according to Embodiment 4 of the present invention. In FIG. 5, portions corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. The power distribution system shown in FIG. 5 differs greatly from the power distribution system shown in FIG. 1, for example, in that an individual determination controller 71 is provided corresponding to the main switch 1. The individual determination controller 71 is connected to the current detector 11 to obtain current information, and obtains current information.
Is configured to be able to transmit an opening / closing control signal to the controller.

Similarly, the individual decision controllers 72a to 72c correspond to the branch switches 2a to 2c, respectively.
The difference is that individual determination controllers 73a to 73c are provided for 3c. Then, for example, the individual determination controller 72c is connected by a signal line so that information can be exchanged with the individual determination controllers 73a to 73c corresponding to the branch switches 3a to 3c located below the corresponding branch switch 2c. It is connected. Further, individual determination controllers 72a to 72
“c” is connected by a signal line so that information can be exchanged with the individual determination controller 71 corresponding to the main switch 1 located above the branch switches 2a to 2c.

Next, the operation will be described. When an accident occurs at an accident point A or B in FIG. 5, the current detector 12c
Detects the fault current. The subsequent operation will be described with reference to FIG. The individual judgment controller 72 for the fault current
“c” determines whether or not the current can be interrupted, that is, whether or not the current is equal to or greater than the interrupting capability of the branch switch 2c. In the case of such a distribution system, the main switch only needs to be able to shut off the maximum current of an accident occurring in the distribution system, and the branch switch does not need to have an interrupting capability for the maximum current.

Thereafter, it is determined whether the accident location is specified, that is, whether the accident is between the branch switch 2c and the branch switches 3a to 3c or lower than the branch switches 3a to 3c. The determination is made based on information from the individual determination controllers 73a to 73c, that is, whether or not the lower-level current detectors 13a to 13c have detected a fault current. When there is no information from the individual determination controllers 73a to 73, the fault point is between the branch switch 2c and the branch switches 3a to 3c as at the fault point B, for example. An accident lower than 3a to 3c, for example, an accident at accident point A.

If the fault current is within the breaking capability of the branch switch 2c and the fault location is, for example, fault point B, the branch switch 2c
This is communicated to the higher order individual determination controller 71 so as to shut off c and not to shut off the higher order main switch 1. In FIG. 6, it is represented as state 2. Within the breaking capacity of the branch switch 2, for example, an accident at the accident point A, the branch switch 3c
Is turned off, the branch switch 2c does not operate and outputs the state 2 to the individual determination controller 71, and the branch switch 3c
When the communication without operating from the individual judgment controller 73c, that is, the state 1 is notified, the branching switch 2c shuts off and sends the state 2 to the upper level.

Next, a case where the fault current is equal to or higher than the breaking ability of the branch switch 2c will be described. If there is no information from the lower individual determination controllers 73a to 73c and it is determined that an accident has occurred at the accident point B, for example, the upper main switch 1
Therefore, it is necessary to cut off the fault current, and the high-order individual judgment controller 71 is turned off by the main switch 1, that is, the state 1 is notified.

In this case, since the branch switch 2c is located closest to and higher than the fault point, the branch switch 2c opens the circuit after the main switch 1 completes the cutoff. Then, the fact that the circuit has been opened is notified to the individual determination controller 71, and the main switch 1 is given re-permission. When the branch switch 3c is interrupted in the case of an accident at the accident point A, the branch switch 2c does not operate and the individual determination controller 71 of the main switch 1 does not operate.
To send state 2. When the branch switch 3c does not shut off, the state 1 is sent to the individual determination controller 71 of the main switch 1. In each of the above-described embodiments, the case where there are a plurality of branch circuits and a plurality of branch switches has been described.

[0043]

According to the first aspect of the present invention, the fault current flowing in any fault in the distribution system is
First, the main switch shuts off, then the branch switch opens the circuit, and then the main switch closes again. The voltage drop time of the circuit can be kept constant and shortened, and there is an effect that the reliability of power supply can be improved, the degree of equipment damage at an accident location can be reduced, and the degree of pressure rise inside the switchboard can be reduced.

According to the second aspect of the present invention, in the first aspect of the present invention, the shutoff ability of the main switch is greater than the shutoff ability of the branch switch so that a predetermined branch switch cannot be shut off by the branch switch. When a large amount of current flows, the main switch is opened and the current is cut off, so the branch switch is capable of breaking the fault current that flows when an accident such as a short circuit occurs below the branch switch. And the size and cost of the branch switch can be reduced.

According to the third aspect of the present invention, in the first aspect of the present invention, the output signal of the current detector is collected by the accident judging control device. Because it was configured to control,
Even in a complicated power distribution system, an accident can be detected and controlled quickly, and there is an effect that it is possible to obtain a power distribution system that has high reliability of power supply and has low damage to equipment and a rise in pressure inside the power distribution device due to the accident.

According to the fourth aspect of the present invention, in the first aspect of the invention, the control of the main switch is made possible by the signal of the current detector close to the main switch, so that the fault current can be cut off at high speed. This has the effect that it can be done reliably.

According to the invention of claim 5, in the invention of claim 1 or 2, an individual judgment controller is provided corresponding to each switch, and each individual judgment controller is placed above the individual judgment controller. The system is connected so that information can be exchanged with the individual judgment controller located below and the individual judgment controller located below, so that accident detection and control can be performed quickly even in complicated distribution systems, and This has the effect of obtaining a power distribution system that is highly susceptible to damage and reduces the pressure rise inside the power distribution device due to an accident, and has an effect that it can easily cope with system expansion and the like.

According to the sixth aspect of the present invention, in any one of the first to fifth aspects of the present invention, the opening command to the branch switch is transmitted after confirming that the fault current has been interrupted by the main switch. With this configuration, an arc with a current value higher than the breaking capability does not occur between the contacts of the branch switch,
There is an effect that the branch switch can be protected.

According to the invention of claim 7, in any one of the inventions of claims 1 to 6, it is confirmed that the main switch interrupts the fault current and the branch switch opens the circuit by opening. Then, since the closing command is sent to the main switch again, there is an effect that the voltage can be restored by closing the main switch after reliably removing the accident.

According to the eighth aspect of the present invention, in any one of the first to seventh aspects of the present invention, a part or all of the main switch and at least one branch switch is a switch having a short opening time. For any accident in the distribution system, the duration of the accident and the voltage drop time of the sound circuit can be shortened constantly and significantly, improving the reliability of power supply, reducing the degree of equipment damage at the accident location, and inside the switchboard. There is an effect that the pressure rise can be reduced.

According to the ninth aspect of the present invention, in any one of the first to eighth aspects of the present invention, a part or all of the main switch and at least one branch switch is a switch having a short closing time. In addition, the restoration of the voltage after disconnection of the faulty circuit can be further speeded up, the voltage drop time of the sound circuit can be further reduced, and the reliability of power supply can be improved.

According to a tenth aspect of the present invention, in the invention of the eighth or ninth aspect, a part or all of the main switch and at least one branch switch are constituted by semiconductor switch elements. There is an effect that the pole / closing can be easily speeded up.

According to an eleventh aspect of the present invention, in the invention of the eighth or ninth aspect, the main switch and at least one of the branch switches have a high-speed response switching operation using an electromagnetic repulsive force in the switching mechanism. Since it is a device, there is an effect that opening and closing can be easily accelerated.

According to a twelfth aspect of the present invention, there is provided the high-speed switch according to the eleventh aspect, wherein the electromagnetic repulsive force is generated by the action of high-frequency currents supplied from an external power supply or by eddy currents. Therefore, there is an effect that opening and closing can be easily accelerated.

[Brief description of the drawings]

FIG. 1 is a simplified circuit diagram showing a configuration of a power distribution system according to a first embodiment of the present invention.

FIG. 2 is a timing chart showing an operation of the power distribution system shown in FIG.

FIG. 3 is a simplified circuit diagram showing a configuration of a power distribution system according to a second embodiment of the present invention.

FIG. 4 is a simplified circuit diagram showing a configuration of a power distribution system according to Embodiment 3 of the present invention.

FIG. 5 is a simplified circuit diagram showing a configuration of a power distribution system according to Embodiment 4 of the present invention.

6 is a flowchart showing an operation of the power distribution system shown in FIG.

FIG. 7 is a simplified circuit diagram showing a configuration of a conventional power distribution system.

FIG. 8 is a diagram showing an effect of a voltage drop on a load device.

[Explanation of symbols]

1 main switch, 2a-2c, 3a-3c branch switch,
11, 12a to 12c, 13a to 13c current detector,
22 first bus, 23 second bus, 31, 32 load, 41 main switching controller, 42 accident determination control device, 5
1, 52a-52c, 53a-53c signal lines, 61,
62a to 62c, 63a to 63c control lines, 71, 72
a to 72c, 73a to 73c Individual determination controllers.

Claims (12)

[Claims] At least one circuit distributed by a distribution conductor is formed in one or more stages on a secondary side of a main switch having a primary side connected to a power receiving end, and the at least one circuit is divided into at least one circuit. Is a power distribution system in which at least one branch switch is disposed, each of which is provided on a primary side or a secondary side of the main switch and at least one branch switch, wherein the main switch and at least one A plurality of current detectors for detecting a magnitude of a current flowing through the branch switch; a detection output of the plurality of current detectors, a predetermined branch switch of the at least one branch switch having a predetermined value or more. When a current flows, the main switch is opened to shut off the current, and immediately thereafter, the predetermined branch switch is opened to open the electric circuit, and thereafter the main switch is opened again. Power control system characterized by comprising a control means for controlling so that pole is. 2. The breaking capacity of the main switch is greater than the breaking capacity of the branch switch, and the control means controls a current of such a magnitude that the predetermined branch switch cannot be cut off by the branch switch. The power distribution system according to claim 1, wherein when the power flows, the main switch is opened. 3. The control means comprises an accident determination control device, wherein detection outputs of the plurality of current detectors are supplied to the accident determination control device, and wherein the accident determination control device comprises a plurality of current detectors. Based on the detection output of the above, one or more branch switches to be opened are specified, and if the current flowing through the specified branch switch is within the breaking capability of the specified branch switch, An opening command is sent to the specified branch switch, otherwise, an opening command is sent to the main switch, and immediately thereafter, an opening command is sent to the specified branch switch. 2. The power distribution system according to claim 1, further comprising: transmitting a closing command to the main switch after that. 4. The control means comprises a main switching controller and an accident determination control device, and a detection output of a first current detector arranged on a primary side or a secondary side of the main switch. Is supplied to the main switching controller, detection outputs of a plurality of second current detectors arranged on the primary side or the secondary side of the at least one branch switch are supplied to the accident determination control device, When a current equal to or greater than a set value is detected by the first current detector, the main switching controller instantaneously sends an opening command to the main switch. Based on the detection output of the current detector 2, the branch switch which is closest to the fault location and which should be opened on the power receiving side of the fault location is specified, and an opening command is sent to the specified branch switch. And then sending a closing command to the main switch. A power distribution system according to claim 1. 5. The control means includes a plurality of individual determination controllers to which detection outputs of the plurality of current detectors are respectively supplied, wherein each of the individual determination controllers is lower than a corresponding switch. Connected to an individual determination controller corresponding to the switch located at the lower position, wherein each of the individual determination controllers is located at the lower level supplied from the detection output of the connected current detector and the lower individual determination controller. The operation of the corresponding switch is determined from the state signal of the switch to control the switch, and the individual determination controller corresponding to the switch located above the corresponding switch is also operated by the corresponding switch. The power distribution system according to claim 1, wherein a power supply status signal is supplied. 6. The control means, when sending an opening command to the branch switch after sending the opening command to the main switch, confirms that the current is interrupted by the main switch. The power distribution system according to any one of claims 1 to 5, further comprising sending an opening command to the specified branch switch. 7. An opening detection means for detecting an opening of the at least one branch switch, wherein the control means transmits a command to the branch switch to close the main switch. When sending the command, after confirming the opening of the electric circuit due to the opening of the branch switch based on the detection output of the opening detection means, sending a closing command to the main switch. Item 7. The power distribution system according to any one of Items 1 to 6. 8. The power distribution system according to claim 1, wherein the opening time of a part or all of the main switch and the at least one branch switch is 10 ms or less. 9. The power distribution system according to claim 1, wherein a closing time of a part or all of the main switch and the at least one branch switch is 10 ms or less. 10. The main switch and the at least one switch.
10. The power distribution system according to claim 8, wherein a part or all of the two branch switches are configured by semiconductor switch elements. 11. The main switch and the at least one
10. The power distribution system according to claim 8, wherein a part or all of the two branch switches are high-speed response switches that use electromagnetic repulsion for the switching mechanism. 11. 12. A driving mechanism for at least the opening or closing of the high-speed response switch, which is directly driven by a repulsive force between high-frequency currents supplied from an external power supply or eddy currents thereby. The power distribution system according to claim 11, wherein: