JP2721194B2 - Power switching control method for power distribution lines - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a power switching control method of a power distribution line for controlling a power switch connected to a power distribution line.

(Prior Art) Normally, as shown in FIG. 9, since a power distribution line 13 can be easily branched, a large number of power slave stations 2 are connected in a multi-drop manner, and power is distributed to a distribution substation 19. Is transmitted to each power substation 2 via the power distribution line 13. Power is transmitted to a number of power slave stations 2 on the power distribution line 13. Power distribution lines
13 has a number of power switches corresponding to a number of power slave stations 2.
14 are arranged in series. An information transmission line 18 is laid along each power distribution line 13, and a command for controlling opening and closing of the corresponding power switch 14 is sent from the control master station 1 to each power slave station 2 as indicated by an arrow 15. Reference numeral 11 denotes a transformer, and reference numeral 12 denotes a power distribution line breaker 12. When insulation breakdown, disconnection failure, or the like occurs in the power distribution line 13, it is necessary to control the opening and closing of the power switch 14 in the distribution section to repair the power line 13. Conventionally, the control master station 1 constantly monitors and detects abnormalities in order to identify a power distribution section in which an accident has occurred. As shown in FIG. 10, conventionally, the information transmission line 18 is composed of two lines in order to avoid distortion of the control signal, and the main line 16a and the backup line 16b are connected to the power slave station 2. Each power slave station 2 uses the information transmission line 18 that is normally used as a main line, and uses the information transmission line 18 that is switched to be used at the time of abnormality as a backup line,
When an abnormality is detected, an operation of switching the information source by the switch 17 is performed.

(Problems to be Solved by the Invention) However, in the conventional method of controlling the power switch of the power wiring, it is necessary to switch the connection with the control master station 1 as the information source from the main line to the backup line. Therefore, an abnormality monitoring device, an abnormality detection device, and a switching device are specially required, so that there is a problem that the technology is complicated and the cost increases. Further, when the information transmission line 18 causes insulation breakdown, disconnection failure, etc., almost all of the power slave stations 2 connected to the information transmission line 18 are generally connected to the information transmission line 18 in a tree shape. There is a problem that the power slave station 2 becomes inoperable. For example, as shown in FIG. 11, when the line impedance of the information transmission line 18 is large, if the line length is long, the supply potential of the control signal is shared by the impedance of the line itself. When this occurs, the supply voltage gradually decreases toward point P, and power slave stations 2 after power slave station # 2 become inoperable. For this reason, several kilometers before and after the accident point become a dead zone for the control master station 1.

The present invention has been made in view of the above circumstances, and prevents all power slave stations connected to an information transmission line in which an accident has occurred from becoming inoperable, and uses various devices such as an abnormality monitoring device. An object of the present invention is to provide a power switching control method of a power distribution line that controls a power switch of the power distribution line without performing the above operation.

(Means for Solving the Problems) In order to achieve the above object, according to the present invention, a plurality of power switches are sequentially arranged in series on a power distribution line, and an information transmission line is arranged along the power distribution line. Are connected to the information transmission line, a plurality of power slave stations for controlling the opening and closing of each of the plurality of power switches, and a control master station for giving a command for controlling the opening and closing of the corresponding power switch to each power slave station. In a power distribution line power switching control system in which a plurality of sets of power distribution line power switching control systems are configured and configured, the information transmission line is connected to the control master station so as to form a closed circuit, the control master station Provides a power switching control method of a power distribution line for transmitting a control signal bidirectionally in a closed circuit, and wherein one information transmission line is connected to the other information transmission line in a closed circuit. Power distribution line power A switching control system is provided, and a plurality of information line switches are interposed in series with the information transmission line, and power switching of a power distribution line in which an information switching control station is connected to each of the information line switches. A control scheme is provided.

(Operation) The information transmission line is configured as a closed circuit with respect to the control master station, and a control signal is transmitted from the control master station in both directions of the closed circuit. Prevent interception of slave station information.

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

FIG. 1 is a schematic configuration diagram of one embodiment of a distribution line power switching control system of a power distribution line power switching control system according to the present invention. The information transmission line 3 is configured to form a loop, that is, a closed circuit with respect to the control master station 1. The information transmission line 3 includes a plurality of power slave stations 2 (# 1, # 2,..., #) That control opening and closing of a power switch in charge based on a command from the control master station 1.
n) are connected in a multi-drop manner. The information transmission line 3 is usually a balanced pair cable wiring. The control master station 1 is configured to transmit a control signal in both directions of the information transmission line 3, as indicated by arrows 4a and 4b. The input impedance of the power slave station 2 is sufficiently higher than the line impedance, and the above-mentioned control signal distributed bidirectionally at the information intake of the power slave station 2 is solid-bonded by compression connection, soldering, or the like with a metal cable. ing. Therefore, each power slave station 2 has the same control master station 1 from both directions.
Receiving the control signal. The information transmission line 3 is
Preferably, the transmission time difference between the two control signals from the control master station 1 to each power slave station 2 is smaller than 1/2 of the time required for on / off transmission of one bit of the transmission speed to be used. Configure the loop network to be less than 4.

FIG. 2 is a schematic configuration diagram of another embodiment of a distribution line power switching control system of the power distribution line power switching control system of the present invention. In this embodiment, each power slave station 2 is connected to two information transmission lines 5 connected to the control master station 1 in a ladder-like closed loop.

FIG. 3 is a block circuit diagram showing the embodiment of the present invention of FIG. 1 in detail. A plurality of power distribution lines 13 are connected in parallel to a transformer 11 of the distribution substation via power distribution line breakers 12, respectively. The power distribution line 13 has a number of power slave stations 2 (# 1,
A number of power switches 14 are arranged in series corresponding to # 2,... #N). The information transmission line 3 is laid along the power distribution line 13 of each system, is solid-bonded to each power slave station 2 with a metal cable and a metal wire, and forms a closed circuit with respect to the control master station 1. . In this embodiment, one information transmission line is connected to another information transmission line so as to form a closed circuit. An information line switch 7 having an open / close switch 7a and an information open / close control station 7b is disposed on the information transmission line 3 for each predetermined section. Code 10
Is a circuit breaker.

As shown in FIG. 4, the speed v of the control signals 8a and 8b transmitted bidirectionally from the same control master station 1 to another information transmission line 3 as indicated by arrows 4a and 4b is approximately v = 200 m. Since the length of the power distribution line 13 is in a range of 10 to 20 km, the power distribution line 13 reaches each power slave station 2 in a required time of 50 to 100 μs.
When there is a distance difference between the control master station 1 and each power slave station 2, the internal impedance of the power slave station 2 on the far side becomes high and the energy is small. Is dominant. The information of the power slave station 2 satisfies the normal function sufficiently at about several hundred bits / sec to 1200 bit / sec due to the nature of the switching operation and the like. That is, 1-bit ON / OFF information may be connected only for half of the period 830 μs (when the speed is 1200 bit / sec), that is, 830/2 = 415 μs. In addition, the fifth
As shown in FIG. 5A, if the voltage level of the control signal 8a is equal to or higher than a predetermined signal detection level Vt, the power slave station 2 can detect the power on / off signal as shown in FIG. 5B.
Thus, even if the information of the power slave station 2 comes from two directions, the information of the power slave station 2 can be sufficiently taken in, and the information transmission line 3 is solid-bonded and input to the power slave station 2. Figure 6 (B) shows the rise or fall time of the signal.
It can be seen that even if the signal fluctuates a little before and after the time τ like jitter, the signal detection of the power slave station 2 has almost no effect.

Next, the operation of the power switching control method for the power wiring line of the present invention will be described with reference to FIG. 3, FIG. 7, and FIG. When a balanced pair cable of 0.9 mm is used as the information transmission line 3, the line constant is the line impedance Zl =
R + 1 / jωC (Ω / Km), resistance R = 53Ω / Km, capacitance C = 50
It can be approximated to × 10 ^-9 F / Km. Use frequency f = 1,000Hz ~
Many are about several KHz, and the line characteristic impedance is about 600Ω. Therefore, when the line length l is about l = several hundreds of meters to 1 km, the information transmission line 3 has a sufficient impedance. Even if the line is short-circuited due to dielectric breakdown or the like before the line length l, it can be regarded as high impedance. I can do it. That is, as shown in FIG. 7 (A), a shared voltage V between the internal impedance Z _in of the power supply 9 (voltage V ₀ ) and the line side impedance Z is obtained.
l is added to the line entrance, and then shares this voltage Vl according to the line length L as shown in FIG. 7 (B).

In the present invention, since a control signal is transmitted from the control master station 1 to the power slave station 2 in both directions of the information transmission line 3, even if a short circuit accident occurs at the point P in FIG. 8
As shown in the figure, only the power slave stations 2 of # 2, # 3 and # 4 become inoperable, and the # 2 remote from the short-circuit fault point P only becomes inoperable.
.., #N are operable. The dead zone is where the supply voltage from the control master station 1 is lower than the signal detection level Vt. Information transmission line 3 with line length l = 10km
As a result of actual confirmation, the power slave station 2 operated sufficiently.

In order to shorten the dead zone, an information line switch 7 shown in FIG. 3 is used. When an accident such as insulation breakdown occurs in the information transmission line 3 and the power slave station 2 stops operating, the control master station 1 sequentially calls each power slave station 2 by boring. Since there is a power slave station 2 that does not respond, all power slave stations 2 of that system
To create a non-response list. First, it is determined from this unresponsiveness list which section of the information transmission line 3 is unresponsive, that is, how much the dead zone is. Next, when the information line switch 7 at the center of the specified non-response section is opened, if one accident point is present, one of the right or left power slave stations 2 is normal and the other does not respond. . Furthermore, the minimum non-response section can be specified by opening the information line switch 7 at the center of the non-response section and successively narrowing the sections in the same manner as described above.

Conventionally, when a metal cable is connected by direct connection or connection in a branch box or the like, an oxide film may be formed at a connection portion due to environmental conditions such as humidity and gas after a long period of time. This oxide film acts equivalently to disconnection of the signal, but a control power supply such as AC100V can destroy the film. Therefore, even if the information transmission line 3 is apparently connected, the connection of the actual control signal is in a defective state. In the present invention, since the information transmission line 3 is connected to a closed circuit, even if such an oxide film occurs, the interruption of information can be sufficiently prevented if there is only one break.

(Effects of the Invention) As described above, according to the present invention, a plurality of power switches are sequentially arranged in series on an electric power distribution line, and an information transmission line is laid along the electric power distribution line. A plurality of power slave stations for controlling the opening and closing of each of the plurality of power switches and a control master station for giving a command for controlling the opening and closing of the corresponding power switch to each power slave station are connected to a transmission line. In a power switching control method for a power distribution line in which a plurality of sets of distribution line power switching control systems exist, the information transmission line is connected to the control master station so as to form a closed circuit, and the control master station is in a closed circuit bidirectional manner. And the information transmission line of one system is connected to the information transmission line of the other system so as to form a closed circuit. Information track switch And the information switching control station is connected to each of the information line switches, so that the conventional abnormality monitoring device, abnormality detecting device, main line spare line switching device, etc. become unnecessary, and the configuration is greatly simplified. Therefore, no special maintenance and inspection is required, and even if a connection failure occurs at the connection point of the information transmission line, the power switch can be controlled sufficiently at one location, and the dead zone of the power slave station can be controlled. The effect of shortening can be obtained.

[Brief description of the drawings]

1 and 2 are schematic diagrams each showing an embodiment of a power distribution control system for a distribution line according to the present invention, and FIG. 3 is an embodiment of the present invention shown in FIG. 4 to 8 are diagrams for explaining the operation of the embodiment of FIG. 3, and FIGS. 9 and 10 are power switching control of a conventional power distribution line, respectively. FIG. 11 is a block circuit diagram showing a system of the system, and FIG. 11 is a diagram for explaining the operation of a conventional power switching control system for power distribution lines. 1: Control master station, 2: Power slave station, 3,5: Information transmission line, 7
... information line switch, 9 ... power supply, 10 ... breaker, 11 ... transformer, 12 ... power distribution line breaker, 13 ... power distribution line, 14 ... power switch.

Claims (3)

(57) [Claims] 1. A plurality of power slave stations for controlling the opening and closing of each of a plurality of power switches sequentially arranged in series in a power distribution line, and an instruction for controlling the opening and closing of the corresponding power switch is given to each power slave station. And the information transmission line connected to the control master station and laid along the power distribution line to form a closed circuit, and the power slave station is connected to a predetermined position. In the power switching control method for a power distribution line, wherein the control master station sends a control signal to the closed circuit, the control master station sends the control signal to the information transmission line simultaneously in both directions. The power transmission line, wherein the information transmission line configures the closed circuit so that a bit shift of the control signal from the two directions reaching the power slave station is within 0 to 1/2 bit. Power switching control method. 2. The information transmission lines are directly connected to each other so that one system of the information transmission lines constituting the closed circuit forms a closed circuit with the other system of information transmission lines. Item 2. A power switching control method for a power distribution line according to Item 1. 3. The closed circuit according to claim 1, wherein the shift of the bit of the control signal is within 0 to 1/4 bits, particularly 0 to 1/4 bits. 3. The power switching control method for a power distribution line according to 1 or 2.