JP7692748B2 - Redundant Systems and Controllers - Google Patents

Description

This invention relates to a redundant system that provides redundancy to network paths, and to a controller that constitutes the redundant system.

In recent years, the open protocol BACnet (Building Automation and Control Network) communication has become widespread in building automation systems. Known communication protocols used in BACnet communication are the "BACnet IP" protocol for communicating BACnet services over Ethernet, and the "BACnet MS/TP (Master Slave Token Passing)" protocol, which uses RS485 for the physical layer of data transmission. Of these, the "BACnet MS/TP" protocol is a protocol that performs communication by combining two communication methods, the master-slave communication method and the token passing communication method. An example of a conventional system configuration to which this BACnet MS/TP protocol is applied is shown in FIG. 17.

In the system shown in FIG. 17, a general-purpose controller 1000, which is a master node, and a secondary device (field device) 50, which is a slave node, are connected in a daisy chain manner (so-called daisy chain) via a serial communication line (MSTP line) 30 according to the RS485 communication protocol, which is a physical layer. The general-purpose controller 1000 has two ports (a first port 1011 and a second port 1012) to which the serial communication line 30 can be connected, and the serial communication line 30 is connected to each port. The general-purpose controller 1000 monitors the status of the secondary device 50 connected to each serial communication line 30 via each serial communication line 30.

Specifically, in this system, a token (communication right) circulates on the network in the order of serial addresses, and a node that acquires this token can communicate with other nodes. When the general-purpose controller 1000 acquires a token, it acquires (scans) status information of the secondary devices 50 connected to each serial communication line 30, thereby monitoring the status of the secondary devices 50. In FIG. 17, reference numeral 80 denotes an integrated controller 80, which is a higher-level controller of the general-purpose controller 1000, and reference numeral 70 denotes a communication line that connects the general-purpose controller 1000 and the integrated controller 80.

If a break occurs along the serial communication line 30, the general-purpose controller 1000 may not be able to access the secondary device 50 connected beyond the point where the break occurred in the serial communication line 30, and may not be able to obtain status information for the secondary device 50.

Meanwhile, various technologies have been proposed to solve problems caused by such line failures. For example, Patent Document 1 discloses a ring network system that quickly switches paths when a line failure occurs.

JP 2006-245780 A

However, the technology described in Patent Document 1 is a technology for providing path redundancy in a system that uses a standard RTP (Resilient Packet Ring) ring network. The network configuration to which this technology is applied is fundamentally different from a network configuration in which secondary devices 50 are connected to serial communication lines 30 in a daisy chain manner. Therefore, it has been difficult to apply the technology described in Patent Document 1 to a network configured with a serial communication line 30 as shown in FIG. 17.

This invention has been made to solve the above problems, and aims to provide a redundant system that can provide redundancy to the paths of a network in which devices are daisy-chained via serial communication lines.

The redundant system of the present invention is composed of a first controller and one or more devices daisy-chained in a ring shape to the first controller by serial communication lines, and the first controller has a first port to which one end of the serial communication line is connected, a second port to which the other end of the serial communication line is connected, and a communication unit capable of serial communication by accessing the devices in a first direction from the first port to the second port, or in a second direction from the second port to the first port.
The communication unit includes a status information acquisition unit that acquires status information of the device through serial communication, and if the status information of each device cannot be acquired from any of the devices as a result of sequentially accessing the devices in either the first direction or the second direction, the status information acquisition unit switches the direction of access to the other of the first direction or the second direction to sequentially access the devices and acquire the status information, and the first controller includes a break determination unit that determines whether or not a break has occurred in the serial communication line based on the result of the status information acquired by the status information acquisition unit, and the break determination unit determines that a break has occurred in the serial communication line when the result of the status information acquired by the status information acquisition unit when the state information acquisition unit accesses the device in either the first direction or the second direction and the result of the status information acquired when the state information acquisition unit accesses the device in the other direction are mutually inverted, and the inverted acquisition result has been acquired continuously a predetermined number of times.

With the above-mentioned configuration, this invention makes it possible to provide redundancy to the network paths in which devices are daisy-chained via serial communication lines.

FIG. 1 is a diagram illustrating a configuration example of a redundant system according to a first embodiment; FIG. 2 is a diagram illustrating a configuration example of a general-purpose controller according to the first embodiment. 11 is a diagram showing an example of a case where no break occurs in the serial communication line in the first embodiment; 4 is a diagram showing an example of an acquisition result of state information in FIG. 3. 11 is a diagram showing an example in which a break occurs in a serial communication line in the first embodiment; 6 is a diagram showing an example of an acquisition result (around a first direction) of state information in FIG. 5 . 6 is a diagram showing an example of an acquisition result (around a second direction) of state information in FIG. 5 . 6 is a diagram showing an example of the result of acquiring state information after the disconnection in FIG. 5 is restored; 4 is a diagram illustrating an example of the operation of the general-purpose controller according to the first embodiment; FIG. FIG. 11 is a diagram illustrating a configuration example of a general-purpose controller according to a second embodiment. 13 is a diagram illustrating an example in which multiple breaks occur in a serial communication line in the second embodiment. FIG. 12A is a diagram showing an example of the state information acquisition result in FIG. 11, where FIG. 12A is a diagram showing an example of the state information acquisition result around a first direction, and FIG. 12B is a diagram showing an example of the state information acquisition result around a second direction. FIG. 13 is a diagram illustrating a configuration example of a general-purpose controller according to a third embodiment. FIG. 13 is a diagram illustrating a configuration example of an operating device according to a third embodiment. FIG. 13 is a diagram illustrating a configuration example of a redundant system according to a fourth embodiment. FIG. 1 is a diagram illustrating a conventional duplexing technique for a heat source controller. FIG. 1 is a diagram showing an example of a conventional system configuration to which the BACnet MS/TP protocol is applied.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
Embodiment 1.
FIG. 1 is a diagram showing an example of the configuration of a redundant system 100 according to the first embodiment.

The redundant system 100 includes a general-purpose controller (first controller) 1 and one or more secondary devices 50 connected in a ring shape to the general-purpose controller 1 via a serial communication line 30. The secondary devices 50 are connected to the general-purpose controller 1 in a daisy chain manner via the serial communication line 30.

The general-purpose controller 1 monitors the status of the secondary devices 50 via the serial communication line 30. As described above, in the redundant system 100, a token (communication right) circulates on the network in the order of serial addresses, and the node that acquires this token communicates with other nodes. When the general-purpose controller 1 acquires a token, it acquires (scans) status information (life/death information) of each secondary device 50 connected to the serial communication line 30, thereby monitoring the status of each secondary device 50. When the general-purpose controller 1 acquires a token, it accesses the secondary device 50 and acquires various information other than the status information held by the device 50 (hereinafter referred to as held information). The serial addresses are assigned to the general-purpose controller 1 and each secondary device 50 in advance by an engineer.

The secondary device 50 is a field device from which status information or retained information is acquired by the general-purpose controller 1. The secondary device 50 is composed of, for example, a controller that controls a variable air volume control device (VAV) in air conditioning control, a controller that controls a fan coil unit (FCU) in air conditioning control, etc.

The integrated controller 80 is a higher-level controller that comprehensively manages lower-level controllers including the general-purpose controller 1, and is connected to the general-purpose controller 1 via a communication line 70 that is different from the serial communication line 30. The integrated controller 80 holds schedule information for the secondary devices 50 (such as air conditioners) that the general-purpose controller 1 monitors. The integrated controller 80 instructs the general-purpose controller 1 to turn the secondary devices 50 ON/OFF (start/stop) according to this schedule information. The communication line 70 is a communication line that allows Ethernet communication using the "BACnet IP" protocol, and the integrated controller 80 and the general-purpose controller 1 can communicate via Ethernet via the communication line 70.

Next, an example of the configuration of the general-purpose controller 1 will be described. As shown in FIG. 2, the general-purpose controller 1 includes a first port 11, a second port 12, a communication unit 13 (a state information acquisition unit 131 and a retained information acquisition unit 132), and a memory unit 14.

The first port 11 is a physical port (terminal) to which one end of the serial communication line 30 is connected. The second port 12 is a physical port (terminal) to which the other end of the serial communication line 30 is connected.

The communication unit 13 accesses the secondary device 50 in a first direction from the first port 11 to the second port 12, or in a second direction from the second port 12 to the first port 11, and performs serial communication with the device 50.

The engineer may set in advance which of the first port 11 and the second port 12 is to be used preferentially. For example, if the engineer sets the first port 11 as the port to be used preferentially, the communication unit 13 will access the secondary device 50 preferentially in the first direction from the first port 11 to the second port 12.

The communication unit 13 includes a state information acquisition unit 131 and a retained information acquisition unit 132. Of these, the state information acquisition unit 131 sequentially accesses the secondary devices 50 in one of the first direction or the second direction, and acquires state information of each device 50. As a result, if state information cannot be acquired from any of the secondary devices 50, the state information acquisition unit 131 switches the access direction to the other of the first direction or the second direction, sequentially accesses the secondary devices 50, and acquires state information of the remaining devices 50, including the device 50 from which state information could not be acquired.

The retained information acquisition unit 132 accesses the secondary device 50 in the first direction or the second direction based on the state information acquired by the state information acquisition unit 131, and acquires information (retained information) that the secondary device 50 retains other than the state information.

The functions of the communication unit 13 (the state information acquisition unit 131 and the retained information acquisition unit 132) are realized, for example, by a central processing unit (CPU) (not shown) provided in the general-purpose controller 1 executing a predetermined program deployed in memory.

The storage unit 14 stores various information used by the general-purpose controller 1. For example, the storage unit 14 stores the results of state information acquisition by the state information acquisition unit 131, the results of retained information acquisition by the retained information acquisition unit 132, and serial address information assigned to each device. The storage unit 14 is composed of, for example, a HDD (Hard Disc Drive), an SSD (Solid State Drive), or a memory. Note that while FIG. 2 shows a case in which the storage unit 14 is provided inside the general-purpose controller 1, the storage unit 14 may also be provided outside the general-purpose controller 1.

Next, an overview of an example of the operation of the general-purpose controller 1 will be described. As described above, the general-purpose controller 1 has a first port 11 and a second port 12 as physical ports to which the serial communication line 30 is connected. In the general-purpose controller 1, the first port 11 and the second port 12 correspond to channels (1CH and 2CH) for performing serial communication with the secondary device 50.

In addition, in the general-purpose controller 1, an engineer assigns a serial address to each channel in advance. For example, the engineer assigns serial address "0" to the first port 11 (1CH) and serial address "127" to the second port 12 (2CH). Similarly, the engineer assigns serial addresses "1" to "126" to the secondary device 50 in accordance with the daisy chain arrangement.

In the redundant system 100, the token circulates along the serial communication line 30 in the order of serial addresses according to the BACnet MSTP protocol specifications. That is, the token circulates from the device with serial address 0 (here, the first port 11) to the devices with serial addresses 1, 2, ..., 126, and finally reaches the device with serial address 127 (here, the second port 12).

When the general-purpose controller 1 acquires the token, it acquires (scans) the status information of the secondary device 50. For example, if the first port 11 (1CH) is set by an engineer as the port to be used preferentially, the status information acquisition unit 131 of the general-purpose controller 1 first sequentially accesses the secondary devices 50 around the first direction from the first port 11 (1CH) to the second port 12 (2CH) based on the serial address information stored in the memory unit 14, and acquires the status information of the secondary devices 50.

This status information is acquired from devices with serial addresses ranging from "1" to "126". The status information acquisition unit 131 may store the status information acquisition result in the storage unit 14. For example, when the status information acquisition unit 131 is able to acquire status information from the device 50 (when there is a response to the scan), the status information acquisition unit 131 stores in the storage unit 14 an acquisition result indicating that status information was acquired for the device 50. On the other hand, when the status information acquisition unit 131 is unable to acquire status information from the device 50 (when there is no response to the scan), the status information acquisition unit 131 stores in the storage unit 14 an acquisition result indicating that status information was unable to be acquired for the device 50.

As an example, consider the case where there is no break in the serial communication line 30, as shown in FIG. 3. The status information acquisition unit 131 accesses the secondary device 50 in the first direction (symbol P in FIG. 3) from the first port 11 (1CH) to the second port 12 (2CH), and acquires status information of that device 50. At this time, since there is no break in the serial communication line 30 in FIG. 3, it is assumed that the status information acquisition unit 131 can acquire status information of all secondary devices 50.

An example of the acquisition result in this case is shown in Figure 4. In Figure 4, the status information acquisition result is stored in the memory unit 14 in table format. In the table in Figure 4, "OK (1)" is entered in the "Current check result" column. This indicates that the status information acquisition unit 131 succeeded in acquiring the status information. Note that "1" is entered in the "Priority scan use CH" column, which indicates that the channel to be used when acquiring the held information of each device is 1CH (first port 11).

Next, consider the case where a break occurs in the serial communication line 30, as shown in FIG. 5. In FIG. 5, a break occurs in the serial communication line 30 at the location indicated by the symbol A. In this case, the status information acquisition unit 131 accesses the secondary device 50 in the first direction (symbol P in FIG. 5) from the first port 11 (1CH) to the second port 12 (2CH) and acquires status information of the device 50. However, it is assumed that while it is possible to acquire status information of the device 50 located before the break in the first direction, it is not possible to acquire status information of the device 50 located beyond the break.

An example of the results obtained in this case is shown in Figure 6. In the table in Figure 6, for the device 50 before the break, "OK (1)" is entered in the "Current check result" column, but for the device 50 beyond the break, "NG (0)" is entered in the "Check result" column. This "NG (0)" indicates that the status information acquisition unit 131 failed to acquire status information. Note that the "NG duration" column in the table in Figure 6 records the time during which the status information acquisition unit 131 has failed to acquire status information.

In this way, if there is even one device for which the acquisition of status information in the first direction has failed, the status information acquisition unit 131 switches the direction of access to the secondary device 50. That is, the status information acquisition unit 131 accesses the secondary device 50 in the second direction (symbol Q in FIG. 5 ) from the second port 12 (2CH) to the first port 11 (1CH), which is opposite to the first direction, and acquires the status information of that device 50.

An example of the results obtained in this case is shown in Figure 7. In the table in Figure 7, it can be seen that the entries in the "Check Results" column are reversed compared to the table in Figure 6. Furthermore, if a device 50 fails to obtain status information in the first direction but succeeds in obtaining status information in the second direction, then "2" is entered in the "Priority Scan CH Used" column for that device 50. This indicates that the channel to be used when obtaining the retained information of that device 50 is CH2 (second port 12).

When the disconnection that occurred at the location A in FIG. 5 is restored, and a device 50 that failed to acquire status information in the first direction before the restoration succeeds in acquiring status information in the first direction after the restoration, the status information acquisition unit 131 rewrites the acquisition result as shown in FIG. 8. That is, the status information acquisition unit 131 clears the "NG duration" for the device 50 that succeeded in acquiring status information in the first direction, and changes the "priority scan available CH" from "2" to "1".

Next, with reference to FIG. 9, an example of the operation of the general-purpose controller 1 according to the first embodiment will be described in detail. It is assumed that the general-purpose controller 1 executes the following process each time it acquires a token. It is assumed below that the first port 11 has been set in advance by an engineer as the port to be preferentially used. It is assumed below that an example is described in which the status information acquisition unit 131 stores the results of acquiring the status information in the storage unit 14, but the status information acquisition unit 131 does not necessarily have to store the results of acquiring the status information in the storage unit 14.

First, the status information acquisition unit 131 accesses the secondary device 50 in the first direction from the first port 11 (1CH) to the second port 12 (2CH) and acquires status information of the device 50 (step ST901).

Next, the state information acquisition unit 131 stores the state information acquisition result when accessing around the first direction in the memory unit 14 (step ST902).

Next, the state information acquisition unit 131 refers to the state information acquisition result stored in step ST902, and checks whether there is any device for which acquisition of state information has failed (step ST903). As a result, if there is no device for which acquisition of state information has failed (step ST903; NO), the general-purpose controller 1 ends the process.

On the other hand, if there is a device for which acquisition of status information has failed (step ST903; YES), the status information acquisition unit 131 accesses the secondary device 50 in the second direction from the second port 12 (2CH) to the first port 11 (1CH) and acquires the status information of that device 50 (step ST904).

Next, the state information acquisition unit 131 stores the state information acquisition result when accessing around the second direction in the storage unit 14 (step ST905), and ends the process.

As described above, according to the first embodiment, the redundant system 100 includes a general-purpose controller 1 and one or more devices 50 daisy-chained in a ring shape to the general-purpose controller 1 by the serial communication line 30. The general-purpose controller 1 includes a first port 11 to which one end of the serial communication line 30 is connected, a second port 12 to which the other end of the serial communication line 30 is connected, and a communication unit 13 capable of accessing the device 50 and performing serial communication around a first direction from the first port 11 to the second port 12, or around a second direction from the second port 12 to the first port 11. This allows the redundant system 100 to make the path of a network in which the devices 50 are daisy-chained by the serial communication line 30 redundant. The redundant system 100 is also effective in terms of cost. For example, in the above-mentioned Patent Document 1, two ring node devices are used to make the path redundant, but in the first embodiment, a redundant system can be realized with one general-purpose controller 1, and a redundant system can be constructed at a lower cost than in the above-mentioned Patent Document 1.

The communication unit 13 also includes a status information acquisition unit 131 that acquires status information of the devices 50 through serial communication. When the status information acquisition unit 131 acquires status information of each device 50 by sequentially accessing the devices 50 in either the first direction or the second direction and fails to acquire status information from any of the devices 50, the access direction is switched to the other direction of the first direction or the second direction to sequentially access the devices 50 and acquire status information. As a result, even if the general-purpose controller 1 fails to acquire status information of a device 50 in either one direction, it can access the device 50 in the other direction, and can continuously acquire status information and monitor the device 50 based on the acquired status information.

The general-purpose controller 1 also includes a first port 11 to which one end of a serial communication line 30 in which one or more devices 50 are daisy-chained in a ring shape is connected, a second port 12 to which the other end of the serial communication line 30 is connected, and a communication unit 13 capable of accessing and communicating serially with the device 50 in a first direction from the first port 11 to the second port 12 or in a second direction from the second port 12 to the first port 11. This allows the general-purpose controller 1 to continuously communicate serially with the device 50.

Embodiment 2.
In the first embodiment, an example has been described in which the general-purpose controller 1 accesses the secondary device 50 in the first direction or the second direction and communicates with the device 50. In addition, in the second embodiment, an example will be described in which the general-purpose controller 1 determines whether or not a break has occurred in the serial communication line 30 based on the result of acquisition of status information of the secondary device 50.

Figure 10 is a diagram showing an example of the configuration of a general-purpose controller 1b according to the second embodiment. The general-purpose controller 1b according to the second embodiment is obtained by adding a disconnection determination unit 15 to the general-purpose controller 1 according to the first embodiment. The other configuration of the general-purpose controller 1b is similar to that of the general-purpose controller 1 according to the first embodiment, so the same reference numerals are used and the description thereof is omitted.

The disconnection determination unit 15 determines whether or not a disconnection has occurred in the serial communication line 30 based on the state information acquired by the state information acquisition unit 131.

For example, when the state information acquisition result by the state information acquisition unit 131 is as shown in FIG. 4, that is, when the state information acquisition unit 131 accesses the secondary device 50 around the first direction and there is no device from which acquisition of state information has failed, the disconnection determination unit 15 determines that no disconnection has occurred in the serial communication line 30.

On the other hand, when the state information acquisition results by the state information acquisition unit 131 are in an inverted relationship as shown in Figures 6 and 7, and these acquisition results are obtained a predetermined number of times in a row, the disconnection determination unit 15 determines that a disconnection has occurred in the serial communication line 30. In other words, the disconnection determination unit 15 determines that a disconnection has occurred in the serial communication line 30 when the acquisition result of the state information when accessed around the first direction and the acquisition result of the state information when accessed around the second direction are in an inverted relationship, and the inverted acquisition result is obtained a predetermined number of times in a row. This prevents the disconnection determination unit 15 from erroneously determining that a disconnection has occurred in the serial communication line 30 due to a temporary restart of the device 50 or the influence of noise.

The disconnection determination unit 15 may determine whether or not a disconnection has occurred in the serial communication line 30 using the above method after the state information acquisition unit 131 acquires state information such as that shown in FIG. 4, or after the state information acquisition unit 131 acquires state information such as that shown in FIGS. 6 and 7.

The disconnection determination unit 15 may determine whether or not a disconnection has occurred at multiple locations on the serial communication line 30 as follows.

For example, as shown in FIG. 11, if breaks occur in multiple locations (here, two locations, marked A and B) in the serial communication line 30, it is expected that the status information acquisition unit 131 will not be able to acquire status information for the device 50 located between the breaks, regardless of whether the device 50 is accessed in the first direction or the second direction.

An example of the information acquisition result in this case is shown in Fig. 12. Fig. 12A shows the state information acquisition result around the first direction, and Fig. 12B shows the state information acquisition result around the second direction.
As shown in Figures 12A and 12B, for two devices 50 (device E) with serial addresses "31" and "32", acquisition of status information fails in both directions when accessed. The "NG duration" indicating the time during which the state of failure to acquire status information of each device 50 continues is 60 seconds. In this way, when the "NG duration" is a predetermined time or more (e.g., 60 seconds or more) and there are a predetermined number or more (e.g., two or more) of devices 50 with the same "NG duration", the disconnection determination unit 15 determines that disconnections have occurred at multiple points in the serial communication line 30. In this case, the predetermined time and the predetermined number can be set to appropriate values by an engineer.

As described above, according to the second embodiment, the general-purpose controller 1 includes a disconnection determination unit 15 that determines whether or not a disconnection has occurred in the serial communication line 30 based on the result of acquisition of status information by the status information acquisition unit 131. This allows the general-purpose controller 1 to determine whether or not a disconnection has occurred in the serial communication line 30.

The disconnection determination unit 15 determines that a disconnection has occurred in the serial communication line 30 when the state information acquisition result obtained when the state information acquisition unit 131 accesses the serial communication line 30 in either the first direction or the second direction is inverted from the state information acquisition result obtained when the state information acquisition unit 131 accesses the serial communication line 30 in the other direction, and the inverted acquisition result is obtained a predetermined number of times in succession. This prevents the disconnection determination unit 15 from erroneously determining that a disconnection has occurred in the serial communication line 30 due to a temporary restart of the device 50 or the influence of noise.

The disconnection determination unit 15 also determines that multiple disconnections have occurred in the serial communication line 30 when the duration of the state in which the state information acquisition unit 131 fails to acquire state information regardless of whether the state information acquisition unit 131 accesses the serial communication line 30 in the first direction or the second direction is equal to or longer than a predetermined time, and there are a predetermined number or more devices with the same duration. This allows the disconnection determination unit 15 to appropriately determine whether multiple disconnections have occurred in the serial communication line 30, even if multiple disconnections have occurred.

Embodiment 3.
In the third embodiment, an example of communication between an operating device and a general-purpose controller in a case where a part of the secondary device 50 is configured with the operating device will be described.

The controller is a device that is composed of at least one of the secondary devices 50, and is capable of accepting operations from an engineer (user) and accessing the general-purpose controller 1 and the integrated controller 80 by itself in response to the operations.

For example, the controller accesses the general-purpose controller 1 (sends an access request) to obtain information held by the general-purpose controller 1 and displays it on the display unit, or updates the information held by the general-purpose controller 1, thereby indirectly operating the secondary device 50. The controller also accesses the integrated controller 80 via the general-purpose controller 1 to change the settings of schedule information for various devices such as air conditioners that is stored in the integrated controller 80. For example, when the controller receives an instruction from a user to extend the operating time of the air conditioner, it sends an access request to the integrated controller 80 to change the schedule information for the air conditioner that is stored in the integrated controller 80.

On the other hand, the controller cannot determine by itself whether or not a break has occurred in the serial communication line 30. Therefore, the general-purpose controller 1c according to the third embodiment generates information (gateway device information) indicating which of its own first port 11 and second port 12 is the gateway device based on the determination result by the break determination unit 15, and transmits the information to the secondary device 50 including the controller. By receiving the gateway device information, the controller recognizes which of the first port 11 and second port 12 is the usable gateway device. Then, the controller transmits an access request to the general-purpose controller 1c and the integrated controller 80 to the gateway device indicated by the gateway device information.

Figure 13 is a diagram showing an example of the configuration of a general-purpose controller 1c according to the third embodiment. The general-purpose controller 1c according to the third embodiment is obtained by adding a transmitting unit 16, a receiving unit 17, a responding unit 18, and a transferring unit 19 to the general-purpose controller 1b according to the second embodiment. The other configuration of the general-purpose controller 1c is similar to that of the general-purpose controller 1b according to the second embodiment, so the same reference numerals are used and the description thereof is omitted.

The transmission unit 16 generates the above-mentioned gateway device information based on the determination result by the disconnection determination unit 15, and transmits the information to the secondary device 50 including the controller.

Specifically, when the disconnection determination unit 15 determines that there is no disconnection in the serial communication line 30, the transmission unit 16 generates gateway device information indicating that either the first port 11 or the second port 12 is a gateway device by the "I-AM-ROUTER" service defined in BACnet, and transmits the generated information simultaneously to the secondary devices 50 by broadcasting it. If a preferential port is set, the transmission unit 16 may generate information indicating that the preferential port is a gateway device.

When the disconnection determination unit 15 determines that a disconnection has occurred in the serial communication line 30, the transmission unit 16 generates information indicating that the first port 11 is a gateway device (first gateway device information) and information indicating that the second port 12 is a gateway device (second gateway device information) by the "I-AM-ROUTER" service defined in BACnet. The transmission unit 16 then broadcasts the first gateway device information from the first port 11 to the secondary devices 50 from which the status information acquisition unit 131 was able to acquire status information when it accessed in the first direction, and broadcasts the second gateway device information from the second port 12 to the secondary devices 50 from which the status information acquisition unit 131 was able to acquire status information when it accessed in the second direction.

The generation and transmission of the gateway device information by the transmission unit 16 may be performed after the disconnection determination unit 15 has determined whether or not a disconnection has occurred in the serial communication line 30.

The receiving unit 17 receives an access request to the controller itself or to the integrated controller 80, which is sent from the access unit 62 of the controller, which will be described later.

When the access request received by the receiving unit 17 is a request for the device itself, the responding unit 18 responds to the access request. For example, when the access request received by the receiving unit 17 is a request to acquire temperature, humidity, CO2 concentration, etc. for the device itself, the responding unit 18 transmits the requested information such as temperature, humidity, and CO2 concentration to the controller 60 in response.

When the access request received by the receiving unit 17 is directed to the integrated controller 80, the transfer unit 19 transfers the access request to the integrated controller 80 via the communication line 70.

Next, an example of the configuration of the controller is shown in FIG. 14. In FIG. 14, reference numeral 60 indicates the controller. As shown in FIG. 14, the controller 60 includes a receiving unit 61, an access unit 62, a storage unit 63, and a display unit 64.

The receiving unit 61 receives gateway device information transmitted from the transmitting unit 16 of the general-purpose controller 1c. The receiving unit 61 also receives information transmitted from the responding unit 18 of the general-purpose controller 1c, i.e., information transmitted in response to an access request from the accessing unit 62 (e.g., information on temperature, humidity, and CO2 concentration). The receiving unit 61 may store the received gateway device information and information received in response to an access request from the accessing unit 62 in the memory unit 63.

The access unit 62 generates an access request in response to an instruction received from a user via, for example, the display unit 64, and transmits the generated access request to the general-purpose controller 1c. At that time, the access unit 62 transmits the access request to the gateway device of the general-purpose controller 1c indicated by the gateway device information received by the receiving unit 61. The transmitted access request is received by the receiving unit 17 of the general-purpose controller 1c via the gateway device of the general-purpose controller 1c.

The storage unit 63 stores various information used by the controller 60. For example, the storage unit 63 stores the gateway device of the general-purpose controller 1c indicated by the gateway device information received by the receiver 61, and information received by the receiver 61 from the response unit 18 of the general-purpose controller 1c. The storage unit 63 is composed of, for example, a hard disc drive (HDD), a solid state drive (SSD), or a memory. Note that while FIG. 14 shows a case where the storage unit 63 is provided inside the controller 60, the storage unit 63 may be provided outside the controller 60.

The display unit 64 displays information (e.g., temperature, humidity, and CO2 concentration) received by the receiver 61 from the response unit 18 of the general-purpose controller 1c. The display unit 64 also displays various screens, such as a screen for turning the air conditioner on and off, or a screen for changing the schedule information for the air conditioner.

In this way, when the access unit 62 sends an access request, it sends the access request to the gateway device indicated by the gateway device information received by the receiving unit 61. In other words, even if the gateway device indicated by the gateway device information changes, the access unit 62 can appropriately switch the access path to the general-purpose controller 1c in response to the change. This allows the controller 60 to continue operation by appropriately switching the access path even if a break occurs in the serial communication line 30.

As described above, according to the third embodiment, the general-purpose controller 1 c is provided with a transmitting unit 16 that generates information indicating which of the first port 11 or the second port 12 is a gateway device based on the determination result by the disconnection determination unit 15, and transmits the information to the device 50.
At least one of the devices 50 is configured with an operator 60 including a receiving unit 61 that receives information transmitted from the transmitting unit 16, and an access unit 62 that transmits an access request for the general-purpose controller 1c to a gateway device indicated by the information received by the receiving unit 61. The general-purpose controller 1c receives the access request transmitted from the access unit 62 via the gateway device.
This allows the general-purpose controller 1c to notify the device 50 of which of the first port 11 or the second port 12 is the gateway device. Even if the gateway device indicated by the gateway device information changes, the operation unit 60 can appropriately switch the access path to the general-purpose controller 1c in response to the change, and can continue operation even if a break occurs in the serial communication line 30.

The access unit 62 also transmits an access request for the integrated controller 80 connected to the general-purpose controller 1c to the gateway device indicated by the information received by the receiving unit 61 via a communication line 70 different from the serial communication line 30, and the general-purpose controller 1c includes a transfer unit 19 that transfers the access request to the integrated controller 80 via the different communication line 70 when the access request transmitted to the gateway device is an access request for the integrated controller 80. This allows the general-purpose controller 1c to appropriately transfer the access request for the integrated controller 80 from the operation device 60 to the integrated controller 80.

Embodiment 4.
In the first to third embodiments, an example has been described in which the paths of a network configured by the serial communication line 30 are made redundant. In the fourth embodiment, in addition to making the paths redundant, an example in which the general-purpose controller itself is made redundant (dualized) will be described.

Figure 15 is a diagram showing an example of the configuration of a redundant system 100 according to embodiment 4. The redundant system 100 according to embodiment 4 includes two general-purpose controllers 1d and 1e. These controllers are connected by serial communication lines 40 and 45. The general-purpose controllers 1d and 1e are also connected to each other and to an integrated controller 80 via a communication line 70.

One of the general-purpose controllers 1d and 1e operates as the active system, and the other operates as the standby system. For ease of understanding, it is assumed here that the general-purpose controller 1d operates as the active system, and the general-purpose controller 1e operates as the standby system. The general-purpose controller 1d operating as the active system is referred to as the "active system controller 1d," and the general-purpose controller 1e operating as the standby system is referred to as the "standby system controller 1e." The information held by the active system controller 1d and the standby system controller 1e is synchronized with each other, for example, via a communication line 70.

The configuration examples of the active controller 1d and the standby controller 1e are the same as the configuration example of the general-purpose controller 1 according to the first embodiment shown in FIG. 2, but here, the configuration examples of the controllers 1d and 1e are explained by adding d or e to the names of the parts shown in FIG. 2.

The active system controller 1d has a first port 11d, a second port 12d, a communication unit 13d (a status information acquisition unit 131d and a retained information acquisition unit 132d), and a memory unit 14d.

The standby controller 1e includes a first port 11e, a second port 12e, a communication unit 13e (a status information acquisition unit 131e and a retained information acquisition unit 132e), and a memory unit 14e.

As shown in FIG. 15, in the redundant system 100, one end of the serial communication line 30 (first serial communication line) is connected to the first port 11d of the active controller 1d, and the other end of the serial communication line 30 is connected to the first port 11e of the standby controller 1e. In other words, in the redundant system 100, the first ports of the general-purpose controllers are connected to each other by the serial communication line 30.

The second port 12d of the active controller 1d and the second port 12e of the standby controller 1e are connected by a serial communication line 40 (second serial communication line). As a result, in the redundant system 100, one large ring-shaped network is formed by the two controllers 1d and 1e, the secondary device 50, and the serial communication lines 30 and 40.

The serial communication line 45 is used to check whether the two controllers 1d, 1e are operating normally. The serial communication line 45 connects the communication port of the active controller 1d to the communication port of the standby controller 1e, and each of the controllers 1d, 1e checks whether the other is operating normally (whether any abnormalities have occurred) via this serial communication line 45.

In the redundant system 100, serial addresses are assigned to the active controller 1d and the standby controller 1e as follows. That is, a serial address "1" is assigned to the first port 11d (1CH) of the active controller 1d, and a serial address "0" is assigned to the second port 12e (2CH) of the standby controller 1e . A serial address "127" is assigned to the second port 12d (2CH) of the active controller 1d, and a serial address "126" is assigned to the first port 11e (1CH) of the standby controller 1e. In this way, different serial addresses are assigned to the channels of the two controllers. The active controller 1d has two channels (1CH and 2CH) as described above, and each channel has two connection ports, and these two connection ports are physically bridge-connected inside the device. Similarly, the standby controller 1e also has two connection ports for each channel, and these two connection ports are physically bridge-connected inside the device. As in the first embodiment, the secondary devices 50 are assigned serial addresses "2" to "125" in advance by an engineer in accordance with the arrangement of the daisy chain.

In the redundant system 100, the first and second directions as viewed from the active controller 1d are as follows. That is, the direction from the first port 11d of the active controller 1d to the second port 12d of the active controller 1d via the first port 11e of the standby controller 1e, the second port 12e of the standby controller 1e, and the serial communication line 40 is the first direction (symbol P in FIG. 15).

Conversely, the direction from the second port 12d of the active controller 1d via the serial communication line 40, the second port 12e of the standby controller 1e, and the first port 11e of the standby controller 1e toward the first port 11d of the active controller 1d is the second rotation direction (symbol Q in FIG. 15). Note that although the standby controller 1e operates as the standby system, it is possible to send and receive information to and from the active controller 1d.

In the redundant system 100, the active controller 1d normally operates as the active system as described above. In this case, the communication unit (active system communication unit) 13d of the active controller 1d accesses the device 50 in the first direction or the second direction and performs serial communication with the device 50. If an abnormality occurs in the active controller 1d, the active controller 1d notifies the standby controller 1e of the occurrence of an abnormality in itself via the serial communication line 45.

The standby controller 1e that receives this notification quickly switches from the standby controller to the active controller, and thereafter operates as the active controller. That is, the communication unit (standby controller communication unit) 13e of the standby controller 1e accesses the device 50 in the second direction (symbol Q in FIG. 15) from its own first port 11e via the first port 11d of the active controller 1d, the second port 12d of the active controller 1d, and the serial communication line 40 toward its own second port 12e, or in the first direction (symbol P in FIG. 15) from its own second port 12e via the serial communication line 40, the second port 12d of the active controller 1d, and the first port 11d of the active controller 1d to its own first port 11e, and performs serial communication with the device 50. As a result, in the redundant system 100d, even if an abnormality occurs in the active controller 1d, the system as a whole can continue to operate, improving system reliability.

The redundant system 100 according to the fourth embodiment is an application of the duplication technology used in conventional heat source controllers to a general-purpose controller. The heat source controller is a controller for controlling heat source equipment in particular, and can be duplicated by connecting an active heat source controller 200a and a standby heat source controller 200b with an I/O module 250 for high-speed communication via Ethernet, as shown in FIG. 16, for example.

The redundant system 100 according to the fourth embodiment applies the concept of the heat source controller duplication technology to a general-purpose controller. In the redundant system 100 according to the fourth embodiment, the duplicated general-purpose controllers 1d and 1e are connected by a serial communication line 40, so that the duplication function can be realized with a less expensive configuration without adding a device such as an I/O module 250 for high-speed communication.

As described above, according to the fourth embodiment, the redundant system 100 includes an active controller 1d, a standby controller 1e, and one or more devices 50 connected to the serial communication line 30. The active controller 1d includes a first port 11d to which one end of the serial communication line 30 is connected, and a second port 12d to which one end of a serial communication line 40 different from the serial communication line 30 is connected. The standby controller 1e includes a first port 11e to which the other end of the serial communication line 30 is connected, and a second port 12e to which the other end of the serial communication line 40 is connected. The active system controller 1d is equipped with an active system side communication unit 13d that can access a device 50 in a first direction from its own first port 11d, via the first port 11e of the standby system controller 1e, the second port 12e of the standby system controller 1e, and the serial communication line 40, toward its own second port 12d, or in a second direction from its own second port 12d, via the serial communication line 40, the second port 12e of the standby system controller 1e, and the first port 11e of the standby system controller 1e, toward its own first port 11d, and can communicate serially with the device 50. The standby controller 1e has a standby communication unit 13e that can access the device 50 in a second direction from its first port 11e to its second port 12e via the first port 11d of the active controller 1d, the second port 12d of the active controller 1d, and the serial communication line 40, or in a first direction from its second port 12e to its first port 11e via the serial communication line 40, the second port 12d of the active controller 1d, and the first port 11d of the active controller 1d, and can communicate serially with the device 50. As a result, the redundant system 100 can make the network path formed by the serial communication lines 30 and 40 redundant, and can continue to operate as a whole system even if an abnormality occurs in the active controller 1d, improving the reliability of the system.

Note that, within the scope of the present invention, the embodiments may be freely combined, any of the components of each embodiment may be modified, or any of the components of each embodiment may be omitted. For example, the redundant system according to embodiment 4 may be combined with the configurations described in embodiments 2 and 3.

1, 1b, 1c General-purpose controller (first controller)
1d General-purpose controller (current system controller)
1e General-purpose controller (standby controller)
11, 11d, 11e First port 12, 12d, 12e Second port 13 Communication unit 13d Active system communication unit 13e Standby system communication unit 14 Memory unit 15 Disconnection determination unit 16 Transmission unit 17 Reception unit 18 Response unit 19 Transfer unit 30, 40, 45 Serial communication line 50 Secondary device 60 Operation unit 61 Reception unit 62 Access unit 63 Memory unit 64 Display unit 70 Communication line 80 Integrated controller (second controller)
100 Redundancy system 131 Status information acquisition unit 132 Retention information acquisition unit P First direction Q Second direction

Claims (8)

A first controller;
one or more devices daisy-chained in a ring shape to the first controller by a serial communication line;
The first controller includes:
a first port to which one end of the serial communication line is connected;
a second port to which the other end of the serial communication line is connected;
a communication unit capable of accessing the device and performing serial communication in a first direction from the first port to the second port or in a second direction from the second port to the first port;
Equipped with
the communication unit includes a status information acquisition unit that acquires status information of the device through serial communication;
The state information acquisition unit
When status information of each device is acquired by sequentially accessing the devices in either the first direction or the second direction, status information cannot be acquired from any of the devices,
a direction of access is switched to another direction around the first direction or the second direction to sequentially access the devices and acquire state information;
The first controller includes:
a disconnection determination unit that determines whether or not a disconnection has occurred in the serial communication line based on a result of acquisition of the status information by the status information acquisition unit;
The disconnection determination unit is
A redundancy system characterized in that the status information acquisition result when the status information acquisition unit accesses around either the first direction or the second direction is inverted to the status information acquisition result when the status information acquisition unit accesses around the other direction, and when the inverted acquisition result is obtained continuously a predetermined number of times, it is determined that a break has occurred in the serial communication line . A first controller;
one or more devices daisy-chained in a ring shape to the first controller by a serial communication line;
The first controller includes:
a first port to which one end of the serial communication line is connected;
a second port to which the other end of the serial communication line is connected;
a communication unit capable of accessing the device and performing serial communication in a first direction from the first port to the second port or in a second direction from the second port to the first port;
Equipped with
the communication unit includes a status information acquisition unit that acquires status information of the device through serial communication;
The state information acquisition unit
When status information of each device is acquired by sequentially accessing the devices in either the first direction or the second direction, status information cannot be acquired from any of the devices,
a direction of access is switched to another direction around the first direction or the second direction to sequentially access the devices and acquire state information;
The first controller includes:
a disconnection determination unit that determines whether or not a disconnection has occurred in the serial communication line based on a result of acquisition of the status information by the status information acquisition unit;
The disconnection determination unit is
A redundancy system characterized by determining that multiple breaks have occurred in the serial communication line when the duration of a state in which the status information acquisition unit fails to acquire status information regardless of whether it accesses the status information acquisition unit in the first direction or the second direction is greater than or equal to a predetermined time, and when there are a predetermined number or more devices with the same duration. A first controller;
one or more devices daisy-chained in a ring shape to the first controller by a serial communication line;
The first controller includes:
a first port to which one end of the serial communication line is connected;
a second port to which the other end of the serial communication line is connected;
a communication unit capable of accessing the device and performing serial communication in a first direction from the first port to the second port or in a second direction from the second port to the first port;
Equipped with
the communication unit includes a status information acquisition unit that acquires status information of the device through serial communication;
The state information acquisition unit
When status information of each device is acquired by sequentially accessing the devices in either the first direction or the second direction, status information cannot be acquired from any of the devices,
a direction of access is switched to another direction around the first direction or the second direction to sequentially access the devices and acquire state information;
The first controller includes:
a disconnection determination unit that determines whether or not a disconnection has occurred in the serial communication line based on a result of acquisition of the status information by the status information acquisition unit;
The first controller includes:
a transmission unit that generates information indicating which of the first port and the second port is a gateway device based on a determination result by the disconnection determination unit, and transmits the generated information to the device;
At least one of the devices
a receiving unit for receiving the information transmitted from the transmitting unit;
an access unit that transmits an access request for the first controller to a gateway device indicated by the information received by the receiving unit,
The first controller includes:
A redundant system, comprising: a gateway device that receives an access request transmitted from the access unit; The access portion of the controller includes:
Transmitting an access request for a second controller connected to the first controller via a communication line different from the serial communication line to a gateway device indicated by the information received by the receiving unit;
The first controller includes:
4. The redundant system according to claim 3, further comprising a transfer unit that, when an access request transmitted to the gateway device is an access request for the second controller, transfers the access request to the second controller via the different communication line. The system includes a current system controller, a standby system controller, and one or more devices connected to a first serial communication line,
The current system controller includes:
a first port to which one end of the first serial communication line is connected;
a second port to which one end of a second serial communication line different from the first serial communication line is connected;
The standby controller includes:
a first port to which the other end of the first serial communication line is connected;
a second port to which the other end of the second serial communication line is connected;
The active system controller includes:
an active system side communication unit that accesses the device in a first direction from a first port of the own device, via a first port of the standby controller, a second port of the standby controller, and the second serial communication line, toward a second port of the own device, or in a second direction from the second port of the own device, via the second serial communication line, the second port of the standby controller, and the first port of the standby controller, toward the first port of the own device, and is capable of serial communication with the device;
The standby controller includes:
a standby system side communication unit that accesses the device in a second direction from a first port of the device via a first port of the active controller, a second port of the active controller, and the second serial communication line toward the second port of the device, or in a first direction from the second port of the device via the second serial communication line, the second port of the active controller, and the first port of the active controller toward the first port of the device, and is capable of serial communication with the device;
the active system communication unit and the standby system communication unit each include a status information acquisition unit that acquires status information of the device through serial communication;
A state information acquisition unit included in the active system communication unit and a state information acquisition unit included in the standby system communication unit,
When status information of each device is acquired by sequentially accessing the devices in either the first direction or the second direction, status information cannot be acquired from any of the devices,
a direction of access is switched to another direction around the first direction or the second direction to sequentially access the devices and acquire state information;
The current system controller includes:
a disconnection determination unit that determines whether or not a disconnection has occurred in the first serial communication line based on a result of acquisition of state information by a state information acquisition unit included in the active system side communication unit;
The standby controller includes:
a disconnection determination unit that determines whether or not a disconnection has occurred in the first serial communication line based on a result of acquisition of state information by a state information acquisition unit included in the standby system side communication unit,
The disconnection determination unit included in the active system controller includes:
determining that a break has occurred in the first serial communication line when a state information acquisition unit included in the active system side communication unit accesses the active system side communication unit in either the first direction or the second direction and when the state information acquisition unit accesses the active system side communication unit in the other direction are inverted to each other and the inverted acquisition results are continuously obtained a predetermined number of times;
The disconnection determination unit included in the standby controller includes:
A redundant system characterized in that the status information acquisition unit provided in the standby system side communication unit determines that a break has occurred in the first serial communication line when the status information acquisition result when the standby system side communication unit accesses the standby system side communication unit in either the first direction or the second direction is inverted from the status information acquisition result when the standby system side communication unit accesses the standby system side communication unit in the other direction, and when the inverted acquisition result is obtained continuously a predetermined number of times. The system includes a current system controller, a standby system controller, and one or more devices connected to a first serial communication line,
The current system controller includes:
a first port to which one end of the first serial communication line is connected;
a second port to which one end of a second serial communication line different from the first serial communication line is connected;
The standby controller includes:
a first port to which the other end of the first serial communication line is connected;
a second port to which the other end of the second serial communication line is connected;
The current system controller includes:
an active system side communication unit that accesses the device in a first direction from a first port of the own device, via a first port of the standby controller, a second port of the standby controller, and the second serial communication line, toward a second port of the own device, or in a second direction from the second port of the own device, via the second serial communication line, the second port of the standby controller, and the first port of the standby controller, toward the first port of the own device, and is capable of serial communication with the device;
The standby controller includes:
a standby system side communication unit that accesses the device in a second direction from a first port of the device via a first port of the active controller, a second port of the active controller, and the second serial communication line toward the second port of the device, or in a first direction from the second port of the device via the second serial communication line, the second port of the active controller, and the first port of the active controller toward the first port of the device, and is capable of serial communication with the device;
the active system communication unit and the standby system communication unit each include a status information acquisition unit that acquires status information of the device through serial communication;
A state information acquisition unit included in the active system communication unit and a state information acquisition unit included in the standby system communication unit,
When status information of each device is acquired by sequentially accessing the devices in either the first direction or the second direction, status information cannot be acquired from any of the devices,
a direction of access is switched to another direction around the first direction or the second direction to sequentially access the devices and acquire state information;
The active system controller includes:
a disconnection determination unit that determines whether or not a disconnection has occurred in the first serial communication line based on a result of acquisition of state information by a state information acquisition unit included in the active system side communication unit;
The standby controller includes:
a disconnection determination unit that determines whether or not a disconnection has occurred in the first serial communication line based on a result of acquisition of state information by a state information acquisition unit included in the standby system side communication unit,
The disconnection determination unit included in the active system controller includes:
determining that a plurality of breaks have occurred in the first serial communication line when a duration of a state in which a status information acquisition unit included in the active system side communication unit fails to acquire status information even when accessed in either the first direction or the second direction is equal to or longer than a predetermined time and there are a predetermined number or more devices with the same duration;
The disconnection determination unit included in the standby controller includes:
A redundant system characterized in that it determines that multiple breaks have occurred in the first serial communication line when the duration of a state in which a status information acquisition unit provided in the standby system side communication unit fails to acquire status information when accessed in either the first direction or the second direction is greater than a predetermined time, and when there are a predetermined number or more devices with the same duration. a first port to which one end of a serial communication line in which one or more devices are daisy-chained in a ring shape is connected;
a second port to which the other end of the serial communication line is connected;
a communication unit capable of accessing the device and performing serial communication in a first direction from the first port to the second port or in a second direction from the second port to the first port;
Equipped with
the communication unit includes a status information acquisition unit that acquires status information of the device through serial communication;
The state information acquisition unit
When status information of each device is acquired by sequentially accessing the devices in either the first direction or the second direction, status information cannot be acquired from any of the devices,
a direction of access is switched to another direction around the first direction or the second direction to sequentially access the devices and acquire state information;
a disconnection determination unit that determines whether or not a disconnection has occurred in the serial communication line based on a result of acquisition of the status information by the status information acquisition unit;
The disconnection determination unit is
A controller characterized in that when the status information acquisition unit accesses the serial communication line in either the first direction or the second direction and the status information acquisition result when the status information acquisition unit accesses the serial communication line in the other direction are inverted, and when the inverted acquisition result is obtained continuously a predetermined number of times. a first port to which one end of a serial communication line in which one or more devices are daisy-chained in a ring shape is connected;
a second port to which the other end of the serial communication line is connected;
a communication unit capable of accessing the device and performing serial communication in a first direction from the first port to the second port or in a second direction from the second port to the first port;
Equipped with
the communication unit includes a status information acquisition unit that acquires status information of the device through serial communication;
The state information acquisition unit
When status information of each device is acquired by sequentially accessing the devices in either the first direction or the second direction, status information cannot be acquired from any of the devices,
a direction of access is switched to another direction around the first direction or the second direction to sequentially access the devices and acquire state information;
a disconnection determination unit that determines whether or not a disconnection has occurred in the serial communication line based on a result of acquisition of the status information by the status information acquisition unit;
The disconnection determination unit is
A controller characterized by determining that multiple breaks have occurred in the serial communication line when the duration of a state in which the status information acquisition unit fails to acquire status information regardless of whether it accesses the status information acquisition unit in the first direction or the second direction is greater than or equal to a predetermined time, and when there are a predetermined number or more devices with the same duration.

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