Control device, control system, and control method

Abstract

A CPU unit (10) is provided with: an auxiliary power supply (12); a power-receiving unit (11); a storage unit (14); an abnormality detection unit (101) that detects an abnormality occurring in at least one device from among the CPU unit (10) and a plurality of external devices including a main power supply unit (20), and saves, in the storage unit (14), abnormality data including data indicating the device in which the abnormality has occurred; a reporting control unit (102) that, on the basis of the abnormality data, reports, using a reporting unit (15), information indicating the device in which the abnormality has occurred; and a power-feeding unit (13) that supplies power to the storage unit (14) and the reporting control unit (102). The storage unit (14) and the reporting control unit (102) operate on the basis of the power supplied by the power-feeding unit (13). The power-feeding unit (14) supplies power from the main power supply unit (20) when the power-receiving unit (11) is capable of receiving power from the main power supply unit (20), and supplies power from the auxiliary power supply (12) when the aforementioned power cannot be received.

Description

Control device, control system, and control method

[0001] The present disclosure relates to a control device, a control system, and a control method.

[0002] In a control system, a technique for indicating the location of an abnormality is known to support maintenance work when an abnormality occurs. For example, Patent Literature 1 discloses a programmable logic controller (PLC) that notifies the location of the abnormality when a system abnormality is detected.

[0003] JP 2011-008496 A

[0004] However, maintenance work to deal with abnormalities may be performed with the power supply to the equipment from the main power supply cut off. For example, the main power supply may be turned off during inspection of the equipment to prevent electric shock or abnormal operation. Alternatively, the power supply to the equipment may be cut off due to a malfunction of the main power supply unit.

[0005] The technology described in Patent Document 1 has a problem in that when the power supply from the main power source is cut off, the location where the abnormality has occurred is not notified, and maintenance work cannot be sufficiently supported.

[0006] In view of the above circumstances, an object of the present disclosure is to provide a control device and the like that can notify the location of an abnormality even when the power supply from the main power source is cut off.

[0007] To achieve the above object, a control device according to the present disclosure includes an auxiliary power source, a power receiving means for receiving power from a main power supply, a memory means, an abnormality detection means for detecting an abnormality occurring in at least one of a plurality of external devices including the main power supply and the control device, and storing abnormality data in the memory means, the abnormality-related data including data indicating which device has the abnormality, an alarm control means for alarming, via a first alarm means, information indicating which device has the abnormality based on the abnormality data stored in the memory means, and a power supply means for supplying power to the memory means and the alarm control means. The memory means and the alarm control means operate based on the power supplied by the power supply means. The power supply means supplies power from the main power supply when the power receiving means is able to receive power from the main power supply, and supplies power from the auxiliary power source when the power receiving means is unable to receive power from the main power supply.

[0008] According to the present disclosure, even when the power supply from the main power source is cut off, it is possible to notify the location where an abnormality has occurred.

[0009] FIG. 1 is a diagram illustrating the overall configuration of a control system according to a first embodiment of the present disclosure; FIG. 2 is a flowchart illustrating an example of a power supply operation by a CPU unit according to the first embodiment of the present disclosure; and FIG. 3 is a diagram illustrating the overall configuration of a control system according to a second embodiment of the present disclosure.

[0010] Hereinafter, a control system according to an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, the same or equivalent parts are denoted by the same reference numerals.

[0011] (First embodiment) A control system 1 according to a first embodiment will be described with reference to Fig. 1. Note that thick dashed arrows in Fig. 1 indicate the connection relationships of power supply lines and the flow of power, and thin dashed lines indicate the connection relationships of communication lines.

[0012] The control system 1 is a control system realized by a programmable logic controller (PLC) including various units. The control system 1 controls sensors, actuators, etc. (not shown). The control system 1 includes a CPU (Central Processing Unit) unit 10, a main power supply unit 20, and one or more expansion units 30. The main power supply unit 20 supplies power to the CPU unit 10 and the expansion units 30. The CPU unit 10 is communicatively connected to the main power supply unit 20 and the expansion units 30. The CPU unit 10, the main power supply unit 20, and the expansion units 30 constitute a PLC. The control system 1 is an example of a control system according to the present disclosure.

[0013] The CPU unit 10 is a unit that performs overall control of the control system 1 as a PLC. The CPU unit 10 normally operates on power supplied from the main power supply unit 20. The CPU unit 10 executes programs to communicate with the expansion unit 30, obtains sensor values ​​obtained from sensors (not shown), and controls actuators (not shown).

[0014] The CPU unit 10 communicates with the main power supply unit 20 and the expansion unit 30 and detects abnormalities in the main power supply unit 20 and the expansion unit 30. When the CPU unit 10 detects an abnormality in the main power supply unit 20 or the expansion unit 30, it notifies the user of information related to the abnormality. The information related to the abnormality includes information indicating at least which unit is abnormal. This notification is also made even when the power supply from the main power supply unit 20 is cut off. The functional configuration of the CPU unit 10 and details of abnormality detection, notification, etc. will be described later. The CPU unit 10 is an example of a control device according to the present disclosure.

[0015] The main power supply unit 20 supplies power to the CPU unit 10 and the expansion unit 30. The main power supply unit 20 is communicatively connected to the CPU unit 10. Through this communication, the CPU unit 10 can detect an abnormality in the main power supply unit 20. The power supply by the main power supply unit 20 can be stopped by the user as appropriate. For example, during maintenance work, the user can stop the power supply by the main power supply unit 20 by turning off a power switch (not shown) provided on the main power supply unit 20 to prevent electric shock, abnormal operation, etc. The main power supply unit 20 is an example of a main power supply device and external device according to the present disclosure.

[0016] The expansion unit 30 operates using power supplied from the main power supply unit 20. The expansion unit 30 is communicably connected to the CPU unit 10. The expansion unit 30 operates under the control of the CPU unit 10. Furthermore, through communication, the CPU unit 10 can detect abnormalities in the expansion unit 30. The expansion unit 30 is a unit such as an input / output unit or a network communication unit. The expansion unit 30 is an example of an external device according to the present disclosure.

[0017] Next, a description will be given of the functional configuration of the CPU unit 10. The CPU unit 10 includes a power receiving unit 11, an auxiliary power supply 12, a power supply unit 13, a storage unit 14, a notification unit 15, and a control unit 100.

[0018] The power receiving unit 11 receives power supplied by the main power supply unit 20. The power receiving unit 11 supplies the received power to the power supply unit 13. When the power receiving unit 11 is unable to receive power from the main power supply unit 20, the supply of power from the power receiving unit 11 to the power supply unit 13 naturally stops. For example, when an abnormality occurs in the main power supply unit 20 and the power supply is cut off, or when the power switch of the main power supply unit 20 is turned off, the supply of power from the power receiving unit 11 to the power supply unit 13 stops. The power receiving unit 11 is an example of a power receiving means according to the present disclosure.

[0019] The auxiliary power supply 12 includes a power supply source such as a dry battery, a rechargeable battery, or a supercapacitor (not shown). The auxiliary power supply supplies power obtained from the power supply source to the power supply unit 13. The auxiliary power supply 12 is an example of an auxiliary power supply according to the present disclosure.

[0020] The power supply unit 13 supplies power to the memory unit 14, the notification unit 15, and the control unit 100. When there is power supply from the power receiving unit 11, that is, when the power receiving unit 11 is able to receive power from the main power supply unit 20, the power supply unit 13 supplies power from the power receiving unit 11 to the memory unit 14, the notification unit 15, and the control unit 100. When there is no power supply from the power receiving unit 11, that is, when the power receiving unit 11 is not able to receive power from the main power supply unit 20, the power supply unit 13 supplies power from the auxiliary power supply 12 to the memory unit 14, the notification unit 15, and the control unit 100. In other words, the power supply unit 13 switches the power supply source for supplying power to the memory unit 14, the notification unit 15, and the control unit 100 depending on whether the power receiving unit 11 is able to receive power from the main power supply unit 20. The power supply unit 13 is an example of a power supply means according to the present disclosure.

[0021] The storage unit 14 stores abnormality data created by the abnormality detection unit 101 (described later). The storage unit 14 operates using power supplied from the power supply unit 13. The storage unit 14 is realized by, for example, a flash memory. The storage unit 14 is an example of a storage means according to the present disclosure.

[0022] The notification unit 15 notifies the user of information regarding an abnormality occurring in the control system 1 based on a notification by the notification control unit 102 described below. The notification unit 15 particularly notifies information indicating which unit has the abnormality. The notification unit 15 operates using power supplied from the power supply unit 13. The notification unit 15 is, for example, a display capable of displaying information regarding the abnormality as an image. Alternatively, the notification unit 15 may be a plurality of lamps that indicate the unit in which the abnormality has occurred and the type of abnormality. Alternatively, the notification unit 15 may be a speaker that can notify information regarding the abnormality by voice. The notification unit 15 is an example of a first notification means according to the present disclosure.

[0023] The control unit 100 controls the CPU unit 10. The CPU unit 10 operates using power supplied from the power supply unit 13. The CPU unit 10 includes an abnormality detection unit 101 and a notification control unit 102.

[0024] The abnormality detection unit 101 communicates with the main power supply unit 20 and the expansion unit 30 and detects abnormalities in the main power supply unit 20 and the expansion unit 30. The abnormality detection unit 101 also detects abnormalities in the CPU unit 10 itself. When the abnormality detection unit 101 detects an abnormality in the main power supply unit 20, the expansion unit 30, or the CPU unit 10, it creates abnormality data, which is data related to the abnormality, and stores it in the memory unit 14. The abnormality data includes data indicating at least which unit has experienced the abnormality. The abnormality detection unit 101 operates using power supplied from the power supply unit 13. The abnormality detection unit 101 is an example of an abnormality detection means according to the present disclosure.

[0025] For example, when communication with one of the main power supply unit 20 and one or more expansion units 30 becomes impossible, the abnormality detection unit 101 detects that a communication abnormality exists in the unit that has lost communication. At this time, the abnormality detection unit 101 creates abnormality data including data indicating that an abnormality has occurred in the unit that has lost communication, and stores the data in the storage unit 14. Alternatively, for example, the abnormality detection unit 101 may communicate with each unit for diagnosis and detect an abnormality based on whether or not an abnormality exists in the diagnosis results. Furthermore, for example, the abnormality detection unit 101 detects that an abnormality exists in a circuit of the CPU unit 10 when a signal that should be emitted from that circuit is interrupted. At this time, the abnormality detection unit 101 creates abnormality data including data indicating that an abnormality has occurred in that circuit, and stores the data in the storage unit 14.

[0026] When the anomaly detection unit 101 does not detect any particular anomaly and past anomaly data is stored in the storage unit 14, the anomaly detection unit 101 deletes the anomaly data.

[0027] The notification control unit 102 refers to the abnormality data stored in the memory unit 14 and notifies information about the abnormality based on the abnormality data by controlling the notification unit 15. The notification control unit 102 particularly notifies information indicating which unit has experienced the abnormality by the notification unit 15. The notification control unit 102 operates using power supplied from the power supply unit 13. The notification control unit 102 is an example of a notification control means according to the present disclosure.

[0028] The notification control unit 102 does not issue any notification when no abnormality data is stored in the storage unit 14. As a result, when no abnormality is detected, no notification is issued from the CPU unit 10.

[0029] Next, an example of the power supply operation by the CPU unit 10 will be described with reference to Fig. 2. The operation shown in Fig. 2 continues to be executed while the CPU unit 10 is running.

[0030] The power supply unit 13 of the CPU unit 10 determines whether the power receiving unit 11 is receiving power from the main power supply unit 20 (step S101). As described above, this is determined by whether power is being supplied from the power receiving unit 11 to the power supply unit 13.

[0031] If power is being received from main power supply unit 20 (step S101: Yes), power supply unit 13 supplies the power received from power receiving unit 11, i.e., the power from main power supply unit 20, to storage unit 14, notification unit 15, and control unit 100 (step S102). Then, the operations from step S101 are repeated.

[0032] If power is not received from the main power supply unit 20 (step S101: No), the power supply unit 13 supplies power from the auxiliary power supply 12 to the storage unit 14, the notification unit 15, and the control unit 100 (step S103). Then, the operations from step S101 are repeated.

[0033] With these operations, even when the power supply from the main power supply unit 20 is cut off, the memory unit 14, the notification unit 15, and the control unit 100 operate using power from the auxiliary power supply 12, so that the abnormality detection unit 101 detects an abnormality and stores the abnormality data in the memory unit 14, and the notification control unit 102 and the notification unit 15 notify information about the abnormality, particularly information indicating which unit has the abnormality. In other words, the CPU unit 10 can notify the location of the abnormality even when the power supply from the main power supply is cut off.

[0034] (Embodiment 2) A control system 1 according to embodiment 2 will be described with reference to Fig. 3. The control system 1 according to embodiment 2 is generally similar to embodiment 1 shown in Fig. 1, except that the CPU unit 10 is communicably connected to a terminal 40. According to the control system 1 according to embodiment 2, information related to an abnormality can be reported not only by the reporting unit 15 of the CPU unit 10 but also by the terminal 40.

[0035] Notification control unit 102 of control unit 100 according to the second embodiment outputs information related to the abnormality to terminal 40 via communication, thereby notifying terminal 40 of the information related to the abnormality. When power receiving unit 11 is able to receive power from main power supply unit 20, power feeding unit 13 supplies power from main power supply unit 20 to control unit 100 and storage unit 14, and therefore notification control unit 102 can output information related to the abnormality to terminal 40. Furthermore, when power receiving unit 11 is not able to receive power from main power supply unit 20, power feeding unit 13 supplies power from auxiliary power supply 12 to control unit 100 and storage unit 14, and therefore notification control unit 102 can similarly output information related to the abnormality to terminal 40.

[0036] The terminal 40 is communicatively connected to the CPU unit 10 and notifies a user of information related to an abnormality based on communication with the notification control unit 102. The terminal 40 is a terminal device such as an industrial personal computer, a display, or a smartphone. The terminal 40 is an example of a second notification means according to the present disclosure.

[0037] (Modifications) In each embodiment, the control system 1 is realized by a PLC, but the control system 1 may be realized by something other than a PLC. For example, the control system 1 may be a master-slave system including one master that receives power from a main power supply and multiple slaves. In this case, the master is an example of a control device according to the present disclosure, and the slaves and the main power supply are examples of external devices according to the present disclosure.

[0038] In each embodiment, the auxiliary power supply 12 has an internal power supply source such as a dry cell battery, a rechargeable battery, or a supercapacitor. However, the power supply source for the auxiliary power supply 12 may be external to the CPU unit 10. For example, in the second embodiment shown in FIG. 3 , the auxiliary power supply 12 may use the terminal 40 as its power supply source and receive power from the terminal 40. In this case, when the power supply from the main power supply unit 20 is cut off and the terminal 40 is not connected to the CPU unit 10, information regarding an abnormality will not be reported. However, this is not a major problem as long as the terminal 40 is always connected to the CPU unit 10 during maintenance work.

[0039] In each embodiment, the control unit 100 of the CPU unit 10 includes an abnormality detection unit 101, which operates using power from the power supply unit 13. However, the abnormality detection unit 101 does not necessarily operate using power from the power supply unit 13, and may operate only when power is being supplied from the main power supply unit 20. Even in this case, if abnormality data is saved while power is being supplied from the main power supply unit 20, even if the power supply from the main power supply unit 20 is subsequently cut off, the memory unit 14, the notification unit 15, and the notification control unit 102 will operate using power from the auxiliary power supply 12, and the CPU unit 10 will be able to notify information related to the abnormality.

[0040] In each embodiment, the abnormality detection unit 101 of the control unit 100 of the CPU unit 10 detects abnormalities in the main power supply unit 20, the expansion unit 30, and the CPU unit 10 itself. Alternatively, the abnormality detection unit 101 may detect abnormalities in only some of these units. For example, the abnormality detection unit 101 may not detect abnormalities in the CPU unit 10 itself. In this case, no notification is given even if an abnormality occurs in the CPU unit 10. However, this configuration may be adopted, for example, if it is obvious to the user that an abnormality has occurred in the CPU unit 10 without the need for notification. Also, for example, the abnormality detection unit 101 may detect only abnormalities in the CPU unit 10 itself.

[0041] In the second embodiment, the CPU unit 10 includes the notification unit 15, and the notification control unit 102 notifies information related to the abnormality through both the notification unit 15 and the terminal 40. Alternatively, the CPU unit 10 may not include the notification unit 15, and the notification control unit 102 may notify information related to the abnormality only through the terminal 40. In this case, the terminal 40 is an example of a first notification means according to the present disclosure.

[0042] In each embodiment, the power supply unit 13 of the CPU unit 10 always supplies power from the auxiliary power supply 12 to the memory unit 14, the notification unit 15, and the control unit 100 when the power supply from the main power supply unit 20 is cut off. However, the power supply unit 13 may switch between supplying and not supplying power from the auxiliary power supply 12 when the power supply from the main power supply unit 20 is cut off based on a user setting. For example, if the power switch of the main power supply unit 20 is often left off for long periods of time during normal operation, there is a possibility that power stored in the power supply source of the auxiliary power supply 12 will be unnecessarily consumed. Therefore, it is convenient if the switching setting can be made by a user setting. This switching setting may be made, for example, by providing a dip switch in the CPU unit 10 and using this dip switch. Alternatively, in the case of the second embodiment shown in FIG. 3 , an engineering tool program may be installed on the terminal 40 and the setting may be made via the engineering tool.

[0043] Furthermore, when configuring the CPU unit 10 via an engineering tool, it may be possible to configure not only the power supply switching settings but also the type of information to be reported as information related to an abnormality. For example, it may be configured to display only the unit in which an abnormality has occurred, or to display the details of the abnormality.

[0044] The present disclosure allows various embodiments and modifications without departing from the broad spirit and scope of the present disclosure. Furthermore, the above-described embodiments are intended to explain the present disclosure and do not limit the scope of the present disclosure. In other words, the scope of the present disclosure is defined by the claims, not the embodiments. Various modifications made within the scope of the claims and the meaning of equivalent disclosures are considered to be within the scope of the present disclosure.

[0045] REFERENCE SIGNS LIST 1 control system, 10 CPU unit, 11 power receiving unit, 12 auxiliary power supply, 13 power supply unit, 14 memory unit, 15 alarm unit, 20 main power supply unit, 30 expansion unit, 40 terminal, 100 control unit, 101 abnormality detection unit, 102 alarm control unit.

Claims

1. A control device comprising: an auxiliary power source; a power receiving means for receiving power from a main power supply; a memory means; an abnormality detection means for detecting an abnormality occurring in at least one of a plurality of external devices including the main power supply and the control device, and storing abnormality data in the memory means which is data related to the abnormality and includes data indicating which device has the abnormality; an alarm control means for notifying by a first alarm means information indicating which device has the abnormality based on the abnormality data stored in the memory means; and a power supply means for supplying power to the memory means and the alarm control means, wherein the memory means and the alarm control means operate based on the power supplied by the power supply means, and the power supply means supplies power from the main power supply when the power receiving means is able to receive power from the main power supply, and supplies power from the auxiliary power source when the power receiving means is unable to receive power from the main power supply.

2. The control device according to claim 1, further comprising the first notification means, wherein the power supply means further supplies power to the first notification means.

3. The control device according to claim 2, wherein the notification control means further notifies via a second notification means external to the control device.

4. A control device as claimed in any one of claims 1 to 3, wherein the power supply means switches between supplying or not supplying power from the auxiliary power source when the power receiving means is unable to receive power from the main power supply device based on a user setting.

5. A control system comprising the control device according to any one of claims 1 to 4 and a plurality of external devices.

6. A control method for a control device, comprising: an auxiliary power source; a power receiving means for receiving power from a main power supply; a memory means; an abnormality detection means for detecting an abnormality occurring in at least one of a plurality of external devices including the main power supply and the control device, and storing abnormality data in the memory means which is data related to the abnormality and includes data indicating which device has experienced the abnormality; and an alarm control means for notifying information indicating which device has experienced the abnormality by a first alarm means based on the abnormality data stored in the memory means; and when the power receiving means is able to receive power from the main power supply, the control method supplies power from the main power supply to the memory means and the alarm control means, and when the power receiving means is unable to receive power from the main power supply, the control method supplies power from the auxiliary power source to the memory means and the alarm control means.

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