JPS5986936A - Optical transmitting device - Google Patents

Abstract

PURPOSE:To improve reliability by providing a switching part for switching a connection to a circuit for inputting information to the forward direction side of an optical branching device or a circuit for inputting it to the reverse direction side. CONSTITUTION:Information transmitted from transmitting parts 3-3n passes through optical branching devices 4-4n for transferring a signal of both the forward and reverse directions to two directions, and also is inputted to a receiving part 1 through optical transmission cables 2-2n for connecting the optical branching devices 4-4n and the receiving part 1 in an annular form. Also, a switching part for connecting to a circuit for inputting an information to the forward direction side of the optical branching devices 4-4n or a circuit for inputting it to the reverse direction side is provided on each transmitting part 3-3n.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an optical transmission device for a supervisory control system for power reception and distribution, air conditioning, power, lighting process control, etc. of buildings, various plants, etc.

[Technical background]

In recent years, signal transmission systems using optical fiber cables have become popular. These systems are ideal for transmitting large amounts of information over long distances, but because of the noise resistance of optical signals and their low frequency, they are now being adopted as information transmission equipment for power and plant monitoring and control. became.

These supervisory control wholesale systems generally have a central monitoring room where remote monitored and controlled objects are aggregated into a plurality of sections, and controlled devices are provided at various locations.

In this case, as a method of signal transmission for supervisory control,
There are radial (called star-shaped, etc.) configurations and annular (loop) configurations. The latter is often used in high-rise buildings and large-scale factories due to the space and amount required for cable installation.

Branchers are used to configure the optical cable transmission line in a ring.There are two types of branchers: optical branchers and repeaters that convert optical to electrical to optical.The latter is more economical, and because it has an electric circuit, it may be noisy depending on the environment. The impact of this and the decline in credibility are issues.

The former has a simple structure and is extremely reliable, except for signal attenuation.

In a supervisory control system, the length of the transmission path is extremely short compared to general public communications, so this attenuation does not pose a problem. Even if something goes wrong with the optical splitter or the original fiber cable, bidirectional transmission is possible. The present invention relates to a highly reliable optical transmission system that can transmit signals from a supervisory control device to a controlled device side.

[Purpose of the invention]

An object of the present invention is to provide a signal transmission optical transmission system based on these ideas that is easily compatible with conventional data transmission systems.

[Summary of the invention]

The present invention includes a receiving section that receives information transmitted by optical transmission, a plurality of transmitting sections that transmit information to this receiving section by optical transmission, and a plurality of transmitting sections that are connected to each of these transmitting sections and from the transmitting section. An optical splitter that transmits signals in both forward and reverse directions, an optical transmission cable that connects these optical splitters and receivers in a ring, and a circuit or information that inputs information to the forward side of the optical splitter. This is an optical transmission device comprising a switching unit that switches between a box and a connection for inputting the signal to the opposite direction side of an optical splitter.

That is, the present invention provides one supervisory control device and a plurality of monitored control devices for the distributed monitored and controlled objects in various processes, one or two sets on the side of one supervisory control device, and two sets on the side of the monitored and controlled device. A set of optical branching devices is installed, and these are connected to each other using optical fiber cables in a circular manner.

B is an optical transmission device of a supervisory control device configured to be able to transmit signals from both directions.

Since the present invention is configured as described above, any one of the pieces 91! Signals can be transmitted from the supervisory control device to the controlled device by transmission from one or both sides, resulting in an economical and improved reliability effect.

[Embodiments of the invention]

Next, the present invention will be explained in detail.

FIG. 1 shows an example of the configuration of a transmission line of a signal light transmission system to which the present invention is applied.

1 indicates the receiving section of the central supervisory control device, and 2.2a.

2b is ex-Fino (-cable, 3.8a,...an
4+4a+...4n represents the transmitting section of the controlled device.

Next, FIG. 2 shows a transmitter P on the controlled device side. This explains the great opportunity of S3. 5 and 5a are conversion units that convert electrical signals into optical signals, 6 is a transmission signal switching unit, 7 is a storage unit, and 8
10 indicates the reset switch, 9 indicates the condition when there is no reply to the transmission from the controlled device side, and 10 indicates the signal interface section with the controlled device, which receives information transmitted by optical transmission. unit 1, and duplicate transmitting units 3, 3a, . . . 3 that transmit information to the receiving unit 1 by optical transmission.
n, and an optical branching device 4, which is connected correspondingly to each of these transmitting units 3, 8a, . 4a...
Original fiber cable 2+ 22112 that connects 4n, optical splitters 4, 4a, ... 4n, and receiving section 1 in a circular manner
b, and a circuit 11 for inputting information to the positive side of the optical splitters 4, 4a, . . .
. . 4n shows an optical transmission device comprising a switching unit 6 for switching the connection to the circuit 11a input to the opposite direction side of 4n.

Next, the operation of this embodiment will be explained using FIGS. 1 and 2. From the transmitting sections 8, 8a, ... 3n of the controlled device, normally the transmitting section 8 → optical branching device 4 → original fiber cable 2 → receiving section 1, transmitting section 3a → optical branching device 4a → optical branching device 4 → original A signal is sent to the receiving unit 1 on the monitoring and control device side through the path of fiber cable 2 → receiving unit 1, transmitting unit 8n → optical splitter 4n → optical splitter 4a → original splitter 4 → optical fiber cable 2 → receiving unit 1. be done.

Next, when a failure occurs at point
Route of original fiber cable 2 → receiving section 1 and transmitting section 3a
The signal can be transmitted from both paths: → optical branching device 4a-+source branching device 4n→receiving section 1 and transmitting section 8n-+optical branching device 4n→receiving section 1. Regarding location Y, transmitter 3→optical splitter 4→optical splitter 4a-+era code splitter 4n→receiver 1, transmitter 8a→optical splitter 4a→optical splitter 4n→receiver 1 and transmitter The signal is transmitted along a path of section 3n→optical branching device 4n→receiving section l.

FIG. 2 explains the signal switching method. Normally, in response to a transmission request from supervisory control, the signal is sent from the signal interface section 10 via the switching section 6 and conversion section 5 to the optical splitter 4, the fiber cable 2a, and then the original fiber. It is transmitted via the cable 2 route.

Next, when the receiving unit 1 of the supervisory control device instructs the controlled device to send information via a route not shown, if there is no response even after the specified time, it is assumed that some kind of failure has occurred and there is no response. The storage circuit 7 is set according to condition 9, the switching section 6 is operated, and the signal interface section 10→
The signal is sent back through the switching unit 6→converting unit 6a circuit, from the optical branching device→optical fiber cable 2a→optical fiber cable 2b, and is transmitted. Reset switch 8 serves to reset the memory circuit after the fault has been removed.

As explained above, even if there is a failure in the optical transmission line i, the electrical-to-optical conversion section of the controlled device, or the receiving section of the monitoring and control device, the control will be carried out by either path as long as two or more conditions do not overlap. It is possible to create an economical and highly reliable system in which signals can be transmitted from the device to the supervisory control device.

FIG. 3 is another embodiment of the invention. 1 indicates the transmitter on the monitoring and control device side, 4, 4a, ... 4n are optical branchers, 2, 2a, 2b are original fiber cables 80.8
0a, . . . aOn represent receiving units on the controlled device side.

FIG. 4 explains the details of one transmitting unit on the supervisory control device side, where 10 represents a signal interface unit for signal transmission and controls the signals to be sent. 6a.

6b is a signal switching section, 7a and 'lb are storage sections, symbol S indicates set, and R indicates reset. 8 is a storage section 7a.

7b is a reset switch, 21 is an OR circuit, and 5a.

5b is a conversion unit that converts an electrical transmission signal into an optical signal; 22a;
, 22b, 28a, 28b are signal converters that convert optical signals into electrical signals, 24a, 24b are original signal monitor circuits, 20a, 20b are optical branchers, 2, 2b
shows the original Phyno Kuichi cable.

Next, the operation of this embodiment will be explained using FIGS. 3 and 4. In the $8 figure, under normal conditions, the signal from one transmitter is transmitted to the optical splitter 4 via the optical fiber cable 2 via the optical splitter 20a, and part of the transmitted light is transmitted to the receiver 30. The remaining light reaches the optical splitter 4a via the striped optical fiber cable 2a and functions in the same manner as the receiver 80, and is transmitted in the same manner and finally passes through the optical splitter 4n. via the optical splitter 20
b and returns to the transmitter IA. Next, when a failure occurs at station X, the original signal k from the transmitting section IA via the optical branching device 2081 and the optical fiber cable 2 reaches the receiving section 30, but is sent to the receiving sections 80a, . . . 30n. Therefore, the original fiber cable 2b and the optical splitter 20b do not result in a single transmitter. In this case, 1. According to the functions described below, the optical branching unit 2051 is connected to the receiving unit 30a, .
b, Original branch 80n 1 Original file/(-Cable 80n
This is done through the following route. ! If there is a failure on the transmitter IA side, the signal can be transmitted to all targets by transmitting from the latter.

The detailed configuration and operation of the MS will be explained with reference to FIG. During normal operation, the signal from the signal interface section 10 from the supervisory control device is sent via the switching section 6a to the electrical to optical conversion section 5.
a, the optical fiber cable 2 via the optical splitter 20a
transmitted to. On the other hand, a part of the signal sent from the optical splitter 20a is monitored for one second by a monitor circuit 24a that is connected to the optical to electrical converter 22a1. Next, the light that has passed through the optical fiber cable 2 is optical branching device 4 → optical fiber cable 2a → source branching device 4a-+ source fiber cable 2a-+
The light is returned to the optical splitter 20b via the original splitter 4r1 → the optical fiber cable 2b, and is further converted from optical to electrical by the converter 22I) and monitored by the monitor circuit 24b.

Assuming that a failure has occurred at point X in FIG. The switching section 6b is closed and the signal of the signal interface section 10 is transferred to the switching section 6b + converting section 5b + original branching device 2.
0b to the optical fiber cable 21), and can be transmitted to all receiving units in both directions. Furthermore, in the event of a failure at location Y or a malfunction in the optical splitter 20a1 converter 22a, etc., the converter 22a→monitor circuit 24a detects the problem, sets the memory 7a, opens the switch 6a, and similarly operates the OR circuit 21. Set the storage section 7b via the switching section 6b.
The circuit is closed and the receiving section 80° 80a, . . . 60n is connected to the converter 5b → optical splitter 20b → optical fiber cable 2b.
It is possible to send to. The reset switch 8 has a function of resetting the storage device when a faulty part is removed.If converters 28a and 28b shown by multi-dot lines are added, it is also possible to monitor the transmission status from the converter 5b.

Next, on the controlled device side, although not shown, if two sets of optical-to-electrical converters are provided, signals can be received through either path.

[Brief explanation of the drawing]

1 and 2 are block diagrams of an optical transmission line explaining one embodiment of the present invention, and FIGS. 8 and 4 are block diagrams explaining other embodiments of the present invention. 1... Receiving section, 2... Optical fiber cable, 8.
... Transmission section, 4... Optical splitter, 5... Conversion section, 6.
...Switching section, 7...Storage section, 20...Optical splitter, 2
1...Order circuit. (7817) Agent Patent Attorney Noriyuki Chika (and 1 other person) Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A receiving section that receives information transmitted by optical transmission, a plurality of transmitting sections that transmit information to this receiving section by optical transmission, and a plurality of transmitting sections that are connected correspondingly to each of these transmitting sections and transmitting information from the transmitting section. An optical splitter that transmits signals in both directions,
An optical transmission group that connects these optical splitters and the receiving section in a ring, and a circuit that inputs the information to the same square side of the optical splitter or a circuit that inputs the information to the opposite side of the optical splitter. 1. An optical transmission device comprising: a switching unit for switching connections between