JP2005311523A - Optical communication control unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect abnormalities, such as disconnection in an optical fiber, in a control unit utilizing optical communication to perform cooperative operation. <P>SOLUTION: When a master control unit is connected to a slave one via an optical fiber in a loop shape to allow a plurality of slave control units to perform the cooperative operation by a command from the master control unit, the property of a communication means is utilized to detect the abnormality of the optical fiber without increasing processing in a CPU for monitoring whether the edge of a reception signal occurs within prescribed time, thus detecting the abnormalities, such as the disconnection in the optical fiber. When the abnormalities of the optical fiber is detected, a disconnection detection signal is outputted, output stop in the slave control unit, or the like is made, and prescribed protection operation is performed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical communication control device that detects an abnormality such as a broken optical fiber and performs a protection operation in a control device that uses optical communication to perform cooperative operation.

As shown in FIG. 15, as a conventional optical communication control device, the master control device 20a transmits a command to the slave control devices 30a to 30c by broadcast communication, and the slave control devices 30a to 30c cooperate based on the command. There is a known form of operation in which one load is moved.
In a power conversion device (hereinafter referred to as a power electronics device) applying power electronics technology, in the case of the above-described form, the devices of the power conversion device 1 are not necessarily housed in one panel. In many cases, the devices are stored in a plurality of panels such as 10 to 13. In such a case, a serial communication line for sending a broadcast command may be performed by optical communication using an optical fiber, both as insulation in each panel and noise countermeasures.

  FIG. 16 shows an example in which a broadcast command is transmitted using optical communication. The master control device 20a and slave control devices 30a to 30c are unidirectionally transmitted / received for home appliances such as audio and FA. Using an electric signal / optical signal converter (hereinafter referred to as “transmission E / O”) and a reception / optical signal / electric signal converter (hereinafter referred to as “reception O / E”) module, the optical fibers 40a to 40d are looped. Connected to.

In FIG. 16, when the disconnection occurs in the optical fiber 40c, the slave control device 30c cannot receive the broadcast command, so that it becomes difficult for the slave control device to move one load in cooperation with the broadcast command. Depending on the situation, the output balance may be lost, and the load 2 and the power converters 50a to 50c may be damaged.
For this reason, the disconnection of the optical fiber is monitored, and when the disconnection occurs, it is necessary to perform a protective operation such as stopping the output of each slave control device.

As a method for detecting disconnection of an optical fiber, a method is known in which communication is determined to be performed at a constant period, and if communication is not performed within a predetermined period, it is regarded as an optical fiber disconnection. (For example, refer to Patent Document 1).
Also, in long-distance optical transmission, the monitoring signal is multiplexed with the optical signal on the optical transmission path and transmitted, and the monitoring signal is wavelength-divided from the optical signal by the WDM filter, and the presence of the monitoring signal is monitored. It is known that an optical fiber breakage is determined by doing so (see, for example, Patent Document 2).
Japanese Patent Publication No. 8-37493 (page 3, FIG. 1) Japanese Unexamined Patent Publication No. 2003-46457 (page 7, FIG. 1)

  However, in the conventional example described in Patent Document 1, since the disconnection of the optical fiber is detected by performing communication at a constant cycle, the master control device takes less time than the cycle for transmitting a command by broadcast communication. When it is desired to detect an optical fiber break, the master controller must perform dummy broadcast communication between command transmission cycles, and the slave controller can receive the dummy communication normally in addition to the broadcast communication command. There is an unresolved problem of increasing the CPU processing load of the master control device and the slave control device.

The conventional example described in Patent Document 2 is a method premised on application to a large-scale optical communication system such as a submarine cable or a telephone network, and is commercially available for home appliances such as audio and FA. However, there is an unsolved problem that the simple optical communication system using the transmission E / O and reception O / E modules is not suitable in terms of cost.
Therefore, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and is simplified using transmission E / O and reception O / E modules commercially available for home appliances such as audio and FA. In an optical communication system, an optical communication control device capable of detecting an abnormality such as disconnection of an optical fiber and performing a predetermined protection operation without increasing the CPU processing load of a master control device and a slave control device is provided. The purpose is that.

  In order to achieve the above object, an optical communication control device according to claim 1 is configured such that one of the plurality of optical communication stations is a master station and the other optical communication station is a slave station. Stations are connected in a loop, and the master station outputs a transmission signal output means that outputs an electric signal with an edge based on a predetermined rule, and monitors the edge of the received signal to monitor the optical transmission line. It is equipped with a monitoring unit that detects an abnormality and outputs an abnormality detection signal when an abnormality in the optical transmission line is detected, and when the abnormality detection signal is output by the monitoring unit of the own station, the protection operation of the slave station is promoted. The slave station is provided with a monitoring unit that monitors an edge of the received signal to detect an optical transmission line abnormality, and outputs an abnormality detection signal when the optical transmission line abnormality is detected. Protect operation when an abnormality detection signal is output It is characterized in Ukoto.

  According to the first aspect of the present invention, the master control device and the slave control device are provided with a reception signal edge monitoring circuit for monitoring an abnormality of the optical fiber, and when the optical fiber is disconnected, the abnormality is detected from the reception signal edge monitoring circuit. A detection signal is output. As a result, the slave control device can perform a predetermined protection operation such as stopping the output signal. For example, in the case where the slave control device moves one load in cooperation with a command from the master control device. In addition, it is possible to suppress damage such as a load caused by the output balance being lost.

An optical communication control apparatus according to claim 2 is the transmission signal output means according to claim 1, wherein the slave station outputs a transmission signal in which an edge is added to an electric signal based on a predetermined rule; When the transmission signal output means of the master station is in a standby state, it comprises switching means for switching between a signal from the transmission signal output means of the own station and a signal from the optical reception means.
In the invention according to claim 2, since the slave control device is provided with the switching means, it normally outputs a signal from the reception O / E, for example, there is a response request designating its own station from the master control device. In this case, the transmission signal output means of the master control device can switch the output signal during the standby state (idle time), and can output the response signal.

The optical communication control device according to claim 3 is the optical communication control device according to claim 1 or 2, wherein the transmission signal output means performs bit stuffing based on a predetermined rule in a communication state to generate a clock component. A guaranteed self-synchronous signal is used as a transmission signal, and in a standby state, a preamble signal is used as a transmission signal.
In the invention according to claim 3, in the case of an incomplete self-synchronous transmission code in which the clock component is lost when 1 continues during communication, such as NRZI, the clock component is performed by performing bit stuffing according to a predetermined rule. Can output a complete self-synchronous transmission signal that is guaranteed, and can output preamble data (frame synchronization data) during idling.

According to a fourth aspect of the present invention, in the optical communication control device according to any one of the first to third aspects, the monitoring unit is configured to transmit an optical transmission line based on whether or not an edge of the received signal is generated within a predetermined time. It is characterized by detecting abnormalities.
In the invention according to claim 4, by utilizing the fact that an edge is generated within a predetermined time in a received signal at the time of communication and at the time of idle, the edge of the received signal is monitored within a predetermined time. An abnormality can be detected and an abnormality detection signal can be output.

The optical communication control apparatus according to claim 5 is the optical communication control apparatus according to claim 1 or 2, wherein the master station is configured to cause an abnormality in the optical transmission line when an abnormality detection signal is output by the monitoring means of the own station. A slave station that outputs a protection operation command to a slave station on the upstream side and receives the protection operation command performs a protection operation when receiving the protection operation command.
In the invention according to claim 5, when the optical fiber is disconnected, the master control device outputs a protection operation command such as a signal stop command to the slave control device upstream from the disconnection point, and the slave control device stops the signal. When the command is received, a predetermined protection operation can be performed in the slave control device.

The optical communication control device according to claim 6 is the optical communication control device according to claim 1 or 2, wherein the transmission signal output means outputs a transmission signal as no signal when an abnormality detection signal is output by the monitoring means of the local station. It is characterized by state.
In the invention according to claim 6, when the optical fiber is disconnected, the transmitting means can be set in a no-signal state so that no edge is generated.

  According to the first aspect of the present invention, in a simple optical communication system in which optical communication stations are connected using optical fiber cables, the master control device transmits a command to the slave control device by broadcast communication, and the slave The control device detects an optical fiber abnormality and stops output without increasing the CPU processing of the master control device or slave control device when operating to move one load in cooperation with the command. The effect that a predetermined protective operation such as can be performed is obtained.

  According to the invention of claim 2, in a simple optical communication system in which optical communication stations are connected using optical fiber cables, the master control device transmits a command to the slave control device by broadcast communication, and the slave control The device detects an optical fiber abnormality without increasing the CPU processing of the master control device or the slave control device, and stops output when operating to move one load in cooperation with the command. The effect that the predetermined protection operation can be performed is obtained.

  According to the invention of claim 3, during communication, in the case of an incomplete self-synchronous transmission code, a bit-stuffing is performed to output a complete self-synchronous transmission code with a guaranteed clock component. In addition, since the preamble data is output at the time of idling, it is possible to obtain an effect that it is possible to output a signal that generates an edge within a predetermined time during communication and at the time of idling.

  Further, according to the invention according to claim 4, by utilizing the fact that an edge occurs within a predetermined time in a received signal during communication and idle time, by monitoring the edge within a predetermined time of the received signal, Abnormalities such as optical fiber breakage can be reliably detected, and an edge monitoring circuit for detecting such an optical fiber abnormality can be realized with a simple digital circuit, which can be easily integrated into an LSI together with a communication controller. The effect of being able to be incorporated into is obtained.

According to the fifth aspect of the invention, when the optical fiber is disconnected, the master control device outputs a stop command to the slave control device upstream from the disconnection point of the optical fiber. An effect is obtained that the device can appropriately perform a predetermined protective operation.
According to the invention of claim 6, when the optical fiber is disconnected, the master control device and the slave control device set the transmission signal output means to the non-signal state so that no edge is generated. It is possible to obtain an effect that a predetermined protective operation can be appropriately performed by detecting the above.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing an optical communication control device according to a first embodiment of the present invention, in which 20a is a master control device as a master station, 30a to 30c are slave control devices as slave stations, In order for the plurality of slave control devices 30a to 30c to perform cooperative operation in response to a command from the control device 20a, the control devices are connected in a loop with optical fiber cables 40a to 40d.

  The master controller 20a includes a CPU 201 that performs control calculations and various controls, a transmission controller 202 as a transmission signal output unit that outputs a self-synchronous transmission signal in which an edge is added to an electrical signal based on a predetermined rule, A transmission E / O 203 is provided as an optical transmission unit that converts an electrical signal generated by the controller 202 into an optical signal and transmits the optical signal to a downstream slave control device.

  The master controller 20a also includes a reception controller 204 that receives a self-synchronous transmission signal, and a reception O / O as an optical receiver that receives an optical signal transmitted from an upstream slave controller and converts it into an electrical signal. E205 and an edge of a signal output from the reception O / E 205 are monitored to detect an abnormality such as a disconnection of the optical fiber. When an abnormality is detected, reception as a monitoring unit that outputs a disconnection detection signal 209 to the CPU 201 is received. And a signal edge monitoring circuit 206.

  When the disconnection detection signal 209 is input to the CPU 201, a signal stop command 210 (not shown) is continuously output from the transmission controller 202. As described above, for example, when the optical fiber is disconnected, a protection operation command is output to the slave control device upstream of the disconnection point of the optical fiber. Therefore, the slave control device that has received this command appropriately performs a predetermined protection operation. be able to.

  The slave control devices 30a to 30c include a CPU 301 that performs control calculation and each control, a transmission controller 302 as a transmission signal output unit that outputs a self-synchronous transmission signal in which an edge is added to an electric signal based on a predetermined rule, A reception controller 304 that receives a self-synchronous transmission signal, a reception O / E 305 that receives an optical signal transmitted from an upstream control device and converts it into an electrical signal, and an input and reception from the transmission controller 302 A signal switching unit 307 serving as a switching unit that switches input from the O / E 305, and a transmission E / O 303 that converts an electrical signal output from the signal switching unit 307 into an optical signal and transmits the optical signal to a downstream control device. I have.

A reception signal edge monitoring circuit that detects an abnormality such as disconnection of an optical fiber by monitoring an edge of a signal output from the reception O / E 305 and outputs a disconnection detection signal 309 to the CPU 301 when the disconnection is detected. 306 and a drive pulse generation unit 308 that receives a drive pulse generation command from the CPU 301 and generates a drive pulse.
That is, when there is no abnormality in the optical fiber, when a drive pulse generation command is output from the CPU 301 to the drive pulse generation unit 308, a drive pulse is output from the drive pulse generation unit 308, and there is an abnormality in the optical fiber. In other words, when the drive pulse generation command is stopped from the CPU 301, the drive pulse output from the drive pulse generation unit 308 is stopped.

In addition, when the slave control devices 30a to 30c receive a signal stop command 210 output when the reception signal edge monitoring circuit 206 of the master control device 20a detects an optical fiber abnormality, a drive pulse is generated from the CPU 301. The command is stopped, and the drive pulse output from the drive pulse generator 308 is stopped.
In the present embodiment, as a transmission code, an NRZI code in which data 0 has a level change and data 1 has no level change as shown in FIG. 2 is used, and transmission controllers 202 and 302, a reception controller 204, Reference numeral 304 denotes an HDLC communication controller.

As shown in FIG. 3, the transmission controller 202 outputs data (broadcast command or the like) set by the CPU 201 during communication, and outputs preamble data (frame synchronization data) during idle, that is, when there is no communication.
Switching between communication and idle time is performed by operating the changeover switch 2025 in the communication / idle switching circuit 2024 to switch between the transmission serial data generation circuit 2022 and the preamble data generation circuit 2023.

  The transmission controller 202 determines the output of the shift register (parallel / serial converter) 20221 for an incomplete self-synchronous transmission code in which a clock component is lost when 1 continues, such as NRZI, during communication. By performing bit stuffing (zero insertion) in the zero insert circuit 20222 in accordance with the established rule, the data nature output from the transmission serial data generation circuit 2022 and the NRZI are combined, and a complete self-synchronous system with a guaranteed clock component The transmission signal is output.

FIG. 4 is a diagram showing an example of zero insertion performed by the zero insert circuit 20222, and is configured to insert 0 data when 1 is continuous for 5 bits in the output signal from the parallel / serial converter 20221. At this time, an edge is generated by inserting 0 data in the signal waveform.
In this way, during communication, the signal waveform has a signal edge within the time T _{A due} to the zero insertion function that inserts 0 data when 1 of 5 bits in the HDLC standard is continuous.

Further, during idle, preamble data as shown in FIG. 5 is output from the preamble data generation circuit 2023. Thus, the idle time is for continuously outputting the HDLC flag data as preamble data, within the signal waveform time T _B is the signal of the edge occurs.
The transmission data format of the master control device 20a includes data A to C as shown in FIG. Here, data A is data indicating broadcast communication, data B is data designating a slave control device number (any one of 30a to 30c) requesting a response, and data C is command data to the slave control devices 30a to 30c. .

  The transmission data format of the slave control devices 30a to 30c includes data D and E. Here, data D is data indicating the slave control device number that has responded, and data E is response data. As shown in FIG. 6, when there is a response request from the master control device 20a, the slave control devices 30a to 30c receive response data when the master control device 20a is idle, that is, during the output of preamble data (HDLC flag data). Send.

That is, the switching timing of the signal switching unit 307 of the slave control devices 30a to 30c is when the master control device 20a is idle, that is, preamble data is being output. In this way, the output signal can be switched at an appropriate timing to output a response signal to the response request from the master control device.
An edge is generated in the signal output from the transmission controller 202 within a predetermined time during communication and idle time. By utilizing this fact, the edge of the signal within a predetermined time is monitored, and the optical fiber is detected. Detect abnormalities such as disconnection.

Specifically, the signal edge is generated within the time T _A during communication, the signal edge is generated within the time T _B during idle, since in the case of HDLC is T _B> T _A, time T _B By monitoring whether or not there is a signal edge within a time T _ERR obtained by adding the switching time and margin of the signal switching unit 307 of the slave control devices 30a to 30c, an abnormality such as an optical fiber breakage is detected. .

Therefore, the master control device 20a and the slave controller 30a~30c received signal edge monitoring circuit 206 and 306, monitors whether there is a signal edge at time T within _ERR, a signal edge at time T in the _ERR If it is detected, the optical fiber is determined to be in a normal state, and if the signal edge cannot be detected within the time _TERR , it is assumed that the optical signal does not reach due to an abnormality such as disconnection of the optical fiber. The disconnection detection signals 209 and 309 are output to the CPUs 201 and 301 based on the determination.

  Therefore, now, it is assumed that the slave control devices 30a to 30c are operating in cooperation based on a command from the master control device 20a. FIG. 7 is a diagram schematically illustrating the communication state of the end of the optical fibers 40a to 40d (outputs of the reception O / Es 205 and 305) and the operations of the CPUs 201 and 301 of the master control device 20a and the slave control devices 30a to 30c. It is. In the upper part of the time axis, a signal surrounded by a bold line is a transmission from the master control device, and when there is a response request to the slave control device, a corresponding slave control device number is given. In the lower part of the time axis, a signal surrounded by a thin line is a transmission from the slave control device, and a slave control device number that has transmitted response data in response to a response request from the master control device is attached.

Responding request is output to the master control device 20a from the slave controller 30c at time t ₀ in FIG. 7, when idle master controller 20a, i.e., at time t ₁ is in the preamble data output, FIG. 7 ( As shown in d), response data is transmitted from the slave control device 30c.
When the response request from the master controller 20a to the slave controller 30a at time t ₂ is outputted, idling of the master control device 20a, i.e., at time t ₃ is in the preamble data output, FIG. 7 (b Response data is transmitted from the slave control device 30a as shown in FIG.

Then, at time t ₄ is the response data transmission of the slave control device 30a, as shown in FIG. 1, it is assumed that disconnection of the optical fiber 40c (figure × mark) occurs. In this case, the optical signal does not reach the end of the optical fibers 40c and 40d on the downstream side of the disconnection point, and communication is interrupted as shown in FIGS. 7 (c) and 7 (d).
For this reason, the reception signal edge monitoring circuits 306 and 206 of the slave control device 30c and the master control device 20a cannot detect the edge of the signal waveform, and disconnection detection signals 309 and 209 are output to the CPUs 301 and 201. As a result, the drive pulse output from the drive pulse generator 308 is stopped in the slave control device 30c, and the master control device 20a, as shown in FIGS. 7 (a) and 7 (b), is located upstream of the broken portion of the optical fiber. A signal stop command 210 is repeatedly output to the slave control devices 30a and 30b.

Then, the slave control devices 30a and 30b receive the signal stop command 210 output from the master control device 20a, and the drive pulse output from the drive pulse generation unit 308 is stopped.
As described above, in the first embodiment, in a simple optical communication system in which optical communication stations are connected in a loop using an optical fiber cable, the master control device transmits a command to the slave control device by broadcast communication. When the slave control device operates to move one load in cooperation with the command, it detects the disconnection of the optical fiber without increasing the CPU processing of the master control device and the slave control device, and outputs the output. A predetermined protection operation such as stopping can be performed.

  In addition, during communication, in the case of an incomplete self-synchronous transmission code, bit stuffing is performed to output a complete self-synchronous transmission code with a guaranteed clock component, and during idle, preamble data is output. It is possible to output a signal in which an edge occurs within a predetermined time during communication and idle time, and by using this fact, it is possible to reliably monitor the optical fiber by monitoring the edge within a predetermined time of the received signal. Abnormalities such as disconnection can be detected.

Furthermore, a reception signal edge monitoring circuit that monitors the presence or absence of an edge of a reception signal within a predetermined time can be realized by a simple digital circuit and can be easily incorporated into an LSI together with a communication controller.
In the first embodiment, the case of including the reception controller 204 of the master control device, the transmission controller 302 of the slave control device, and the signal switching unit 307 has been described. However, the present invention is not limited to this, and FIG. An optical communication control device as shown in FIG. In this case, the slave control device is connected so that the signal output from the reception O / E 305 is input to the transmission E / O 303, the reception controller 304, and the reception signal edge monitoring circuit 306. Then, the received signal edge monitoring circuit 206 and 306, it is possible to detect an abnormality of the optical fiber by monitoring whether there is a signal edge at time T within the time obtained by adding T _ERR1 the margin to _B.

Next, a second embodiment of the present invention will be described.
In the second embodiment, the transmission controller has a no-signal state, and when a disconnection detection signal is output from the reception signal edge monitoring circuit, the transmission controller is switched to the no-signal state.
FIG. 9 is a diagram illustrating the transmission controller 202 in the second embodiment. In the transmission controller 202 in the first embodiment illustrated in FIG. 3, the disconnection detection signal 209 is output from the reception signal edge monitoring circuit 206 to the CPU 201. 3 has the same configuration as that of FIG. 3, except that it is configured to output a no-signal state, and the same parts as those in FIG. To do.

Therefore, now, it is assumed that the slave control devices 30a to 30c are operating in cooperation based on a command from the master control device 20a. FIG. 10 is a diagram schematically illustrating the communication state of the end of the optical fibers 40a to 40d (outputs of the reception O / Es 205 and 305) and the operations of the CPUs 201 and 301 of the master control device 20a and the slave control devices 30a to 30c. It is. When the response request from the master controller 20a to the slave controller 30a at time t ₂ is outputted, idling of the master control device 20a, i.e., at time t ₃ is in the preamble data output, in FIG. 7 (b) As shown, response data is transmitted from the slave control device 30a.

Then, at time t ₄ is the response data transmission of the slave control device 30a, as shown in FIG. 1, it is assumed that disconnection of the optical fiber 40c (figure × mark) occurs. In this case, the optical signal does not reach the end of the optical fibers 40c and 40d on the downstream side of the disconnected portion, and communication is interrupted as shown in FIGS. 10 (c) and 10 (d).
For this reason, the reception signal edge monitoring circuits 306 and 206 of the slave control device 30c and the master control device 20a cannot detect the edge of the signal waveform, and disconnection detection signals 309 and 209 are output to the CPUs 301 and 201. As a result, in the slave control device 30c, the drive pulse output from the drive pulse generation unit 308 is stopped and the transmission controller 302 is switched to the no-signal state, and in the master control device 20a, the transmission controller 202 is switched to the no-signal state.

  When the transmission controller 202 of the master control device 20a is switched to the no-signal state, there is no signal edge. Therefore, in the slave control device 30a, the reception signal edge monitoring circuit 306 outputs the disconnection detection signal 309, and the transmission controller 302 While switching to the no-signal state, the CPU 301 stops the drive pulse output command.

As a result, the response transmission of the slave control device 30a is interrupted and no signal is generated. Therefore, also in the slave control device 30b, the reception signal edge monitoring circuit 306 outputs the disconnection detection signal 309, and the transmission controller 302 is in the no signal state. The CPU 301 stops the drive pulse output command.
As described above, in the second embodiment, when the optical fiber is disconnected, the transmission controller is set to a no-signal state so that no edge is generated. Therefore, the disconnection is detected in the slave control device and a predetermined protection operation is appropriately performed. be able to.

Next, a third embodiment of the present invention will be described.
In the third embodiment, a bidirectional module in which transmission E / O and reception O / E are included in one module and a bidirectional optical fiber are applied.
As shown in FIG. 15, when the control devices are separately housed in the panels 10 to 13, the lengths of the optical fibers 40a to 40d are substantially equal if the panels 10 to 13 can be arranged as shown in FIG. Can be. However, as shown in FIG. 12, there are many cases in which the panels 10 to 13 are arranged in a line, and in such a case, the line length of the optical fiber 40d becomes extremely long, and communication cannot be performed due to attenuation of the optical signal. Sometimes.

Therefore, using a bidirectional module in which transmission E / O and reception O / E are contained in one module as a set, the panels 10 to 13 are arranged in a line as shown in FIG. The fibers 41a to 41c are connected.
FIG. 14 is a configuration diagram when the bidirectional module shown in FIG. 13 is used, in which the bidirectional module 701 of the master controller 70a and the bidirectional module 801a of the slave controller 80a are connected by an optical fiber 41a. The bidirectional module 802a of the control device 80a and the bidirectional module 801b of the slave control device 80b are connected by an optical fiber 41b, and the bidirectional module 802b of the slave control device 80b and the bidirectional module 801c of the slave control device 80c are optical fibers. 41c is connected.

In the slave control devices 80a and 80b, the output of the reception O / E of the bidirectional module 801 is connected to the transmission E / O of the bidirectional module 802, and the output of the reception O / E of the bidirectional module 802 is the signal switching unit 308. To the bi-directional module 801 transmitting E / O.
Further, in the slave control device 80c that is the terminal, the output of the reception O / E of the bidirectional module 801c is connected to the transmission E / O of the bidirectional module 801c via the signal switching unit 308.

Thereby, the communication path of the master control apparatus 70a and the slave control apparatuses 80a-80c can be comprised similarly to the 1st and 2nd embodiment mentioned above.
Therefore, as shown in FIG. 14, when the optical fiber 41b is disconnected (indicated by a cross in the figure), the edge of the signal waveform is received by the received signal edge monitoring circuits 306 and 206 of the slave controller 80a and the master controller 70a. Cannot be detected, and an optical fiber abnormality is detected, and disconnection detection signals 309 and 209 are output. Thereby, each control apparatus can perform a predetermined protective operation.

  As described above, in the third embodiment, by applying the bidirectional module in which the transmission E / O and the reception O / E are included in one module, the line length of the specific optical fiber is extremely long. The boards 10 to 13 can be arranged in a linear form without suppressing the attenuation of the optical signal and stable communication can be performed, and the optical fiber without increasing the CPU processing of the master controller or slave controller It is possible to appropriately perform a predetermined protection operation such as detecting disconnection of the power supply and stopping the output.

It is a block diagram which shows the 1st Embodiment of this invention. It is a table | surface explaining the transmission code NRZI. It is a figure explaining the transmission controller of FIG. 1 in 1st Embodiment. It is a figure explaining the example of zero insert. It is a figure explaining the example of preamble data. It is a figure explaining a transmission format and a communication state. It is a figure which shows the communication state at the time of the optical fiber disconnection in 1st Embodiment, and operation | movement of CPU. It is a block diagram which shows the other example in 1st Embodiment. It is a figure explaining the transmission controller of FIG. 1 in 2nd Embodiment. It is a figure which shows the communication state at the time of the optical fiber disconnection in 2nd Embodiment, and operation | movement of CPU. It is a figure which shows the cyclic | annular arrangement | positioning of the board using a unidirectional module. It is a figure which shows the linear arrangement | positioning of the board using a unidirectional module. It is a figure which shows the linear arrangement | positioning of the board using a bidirectional | two-way module. It is a block diagram which shows the 3rd Embodiment of this invention. It is a figure explaining the prior art. It is a figure explaining the prior art using an optical fiber.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Power converter device which applied power electronics technology 2 Load 10-13 board 20a Master controller 30a-30c Slave controller 201,301 CPU
202, 302 Transmission controller 203, 303 Transmission E / O
204,304 Reception controller 205,305 Reception O / E
206, 306 Received signal edge monitoring circuit 307 Signal switching unit 308 Drive pulse generation unit 40a-40d Unidirectional optical fiber 41a-41c Bidirectional optical fiber 70a Master controller 80a-80c Slave controller

Claims (6)

A plurality of optical communication units comprising: an optical transmission unit that converts an electrical signal into an optical signal corresponding thereto and transmits the optical signal; and an optical reception unit that receives the optical signal and converts the optical signal into an electrical signal corresponding to the optical signal to obtain a reception signal. In an optical communication control apparatus that has a station, connects each optical communication station using the optical transmission path via the optical transmission means and the optical reception means, and performs data transmission between the optical communication stations,
Of the plurality of optical communication stations, one optical communication station is a master station, the other optical communication stations are slave stations, and the optical communication stations are connected in a loop. The master station is based on a predetermined rule. Transmission signal output means for outputting a transmission signal with an edge added to the electrical signal, and detecting an abnormality in the optical transmission line by monitoring the edge of the reception signal, and detecting an abnormality detection signal when an abnormality in the optical transmission line is detected. Monitoring means for outputting, and when an abnormality detection signal is output by the monitoring means of the local station, the slave station is urged to protect the slave station, and the slave station monitors the edge of the received signal to detect an optical transmission line abnormality. And monitoring means for outputting an abnormality detection signal when an abnormality in the optical transmission line is detected, and a protective operation is performed when the abnormality detection signal is output by the monitoring means of the local station. Communication control device.   The slave station has a transmission signal output means for outputting a transmission signal with an edge added to an electrical signal based on a predetermined rule, and a transmission signal of the own station when the transmission signal output means of the master station is in a standby state. 2. The optical communication control apparatus according to claim 1, further comprising switching means for switching between a signal from the output means and a signal from the optical receiving means.   The transmission signal output means uses a self-synchronous signal in which a clock component is guaranteed by performing bit stuffing based on a predetermined rule in a communication state, and a preamble signal as a transmission signal in a standby state. The optical communication control device according to claim 1, wherein the optical communication control device is an optical communication control device.   4. The optical communication control apparatus according to claim 1, wherein the monitoring unit detects an abnormality in the optical transmission path based on whether or not an edge of the received signal is generated within a predetermined time.   The master station, when an abnormality detection signal is output by the monitoring means of its own station, outputs a protection operation command to the slave station upstream from the location where the abnormality occurred in the optical transmission path, and receives the protection operation command 3. The optical communication control apparatus according to claim 1, wherein the slave station performs a protection operation when receiving the protection operation command.   The optical communication control device according to claim 1 or 2, wherein the transmission signal output means puts the transmission signal in a no-signal state when an abnormality detection signal is output by the monitoring means of the local station.

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