PLC control system and method for providing object communication

Abstract

The present invention relates to a PLC control system and method for providing object communication. The PLC control system includes at least one user terminal and multiple dictionaries, includes a PLC for performing generation, deletion, or modification of an object including at least one item according to an object write signal received from the user terminal during operation on the basis of at least one pre-generated object, and is also applicable to other embodiments.

Description

PLC control system and method providing object communication

[0001] The present invention relates to a PLC control system and method for providing object communication.

[0002] CAN (control area network) communication is a message-based multiplex protocol designed to enable microcontrollers and various devices to communicate with each other without a host computer, and is a serial communication that is an industrial standard used in various fields such as automobiles, various industrial machinery, and medical devices.

[0003] Among them, CANOpen communication is one of the many advanced CALs (CAN application layers) that support the CAN specification and extend the functionality of CAN, and as a protocol that supports CAN communication, it is also used for network management and monitoring of PLC (programmable logic controller) devices in various industrial settings.

[0004] In CAN-based communication, including CANOpen, a single object dictionary is used according to the object communication mechanism, but there is complexity in that incoming PDOs (process data objects) and outgoing PDOs must be distinguished and managed. Consequently, there is the inconvenience of having to configure and manage objects separately depending on the type of service, and communication flexibility is limited. In particular, since the configuration and modification of PDO mapping information are only possible in the pre-operational state, there is a constraint that new types of PDOs cannot be added or existing PDOs modified while the system is actually in operation.

[0005] In other words, if you want to process data that is not predefined while in operation, you must switch the device to a non-operational state to change the PDO mapping, which increases the downtime of the device and significantly reduces system availability. Therefore, the existing CAN-open communication method has the disadvantage of limiting flexibility in application environments requiring high availability because it does not support real-time changeable object management and mapping settings.

[0006] Embodiments of the present invention for solving these conventional problems provide a PLC control system and method that provide object communication capable of enabling the dynamic creation and modification of new objects while ensuring continuous operation of the PLC while the PLC is in operation.

[0007] A PLC control system providing object communication according to an embodiment of the present invention is characterized by including at least one user terminal and a plurality of dictionaries, and including a PLC that performs the creation, deletion, or modification of an object including at least one item according to an object write signal received from the user terminal during operation based on at least one previously created object.

[0008] In addition, the PLC is characterized by transmitting data related to the created or modified object to the user terminal according to a read signal received from the user terminal.

[0009] In addition, the plurality of dictionaries is characterized by including an item dictionary and an object dictionary.

[0010] In addition, the object dictionary is characterized as being a collection of at least one previously created object and objects created or modified by the user terminal.

[0011] In addition, the objects included in the object dictionary are characterized by including item containers.

[0012] In addition, the item container is characterized by including storage location information of at least one item connected to an object included in the object dictionary.

[0013] In addition, the item dictionary is characterized by mapping each of the multiple data identified in the PLC to the storage location information of the corresponding item.

[0014] In addition, the item dictionary is characterized by extracting data mapped to the storage location information of at least one item.

[0015] In addition, a PLC control method providing object communication according to an embodiment of the present invention is characterized by comprising the steps of: receiving an object write signal from at least one user terminal during operation based on at least one object created by a PLC including a plurality of dictionaries; and the PLC performing the creation, deletion, or modification of an object including at least one item according to the object write signal.

[0016] As described above, the PLC control system and method for providing object communication according to the present invention can maximize the availability of the PLC and secure flexibility to provide various forms of data in real time according to user requests by enabling the dynamic creation and modification of new objects while ensuring continuous operation of the PLC while the PLC is in operation.

[0017] FIG. 1 is a drawing showing a PLC control system providing object communication according to an embodiment of the present invention.

[0018] FIG. 2 is a flowchart for explaining a PLC control method that provides object communication according to an embodiment of the present invention.

[0019] FIG. 3 is an illustrative diagram for explaining a method of performing a read operation of a pre-generated object for object communication according to an embodiment of the present invention.

[0020] FIGS. 4 and FIGS. 5 are exemplary diagrams for explaining object frames of an object generated according to a write signal according to an embodiment of the present invention.

[0021] FIG. 6 is an illustrative diagram for explaining a method of modifying an object for object communication according to an embodiment of the present invention.

[0022] The national research and development projects that supported this invention are as follows.

[0023] [Project ID] 2410004419

[0024] [Assignment No.] 20022994

[0025] [Ministry Name] Ministry of Trade, Industry and Energy

[0026] [Name of Project Management (Specialized) Agency] Korea Institute of Industrial Technology Planning and Evaluation

[0027] [Research Project Name] Development of Technology for the Machinery and Equipment Industry

[0028] [Research Project Title] Standard-based Controller Advancement and Digital Twin-based Controller Performance Verification

[0029] Technology development

[0030] [Executing Organization Name] Korea Electronics & Technology Institute / Joint R&D Organization Name: LS ELECTRIC

[0031] [Research Period] 2023.04.01 ~ 2025.12.31

[0032] Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. The detailed description disclosed below, together with the accompanying drawings, is intended to describe exemplary embodiments of the present invention and is not intended to represent the only embodiment in which the present invention can be practiced. In order to clearly explain the present invention in the drawings, parts unrelated to the description may be omitted, and the same reference numerals may be used for identical or similar components throughout the specification.

[0033] FIG. 1 is a drawing showing a PLC control system providing object communication according to an embodiment of the present invention.

[0034] Referring to FIG. 1, the PLC control system (10) according to the present invention includes a PLC (100) and a plurality of user terminals (200), and the PLC (100) may include an object dictionary (110) and an item dictionary (120).

[0035] The PLC (100) creates, deletes, or modifies an object according to a write signal received from a user terminal (200) through communication with a plurality of user terminals (200), and transmits data corresponding to the created or modified object to the user terminal (200) according to a read signal received from the user terminal (200). At this time, the PLC (100) and the user terminal (200) can perform Ethernet communication such as CAN-Open, EtherCAT, RAPIEnet, etc.

[0036] The PLC (100) uses a dual dictionary including an object dictionary (110) and an item dictionary (120). The object dictionary (110) represents a collection of service processing units according to the purpose of the user terminal (200), and the item dictionary (120) may represent a collection of data of minimum information units obtained from the PLC (100).

[0037] The user terminal (200) communicates with the PLC (100) through the object dictionary (110), and the item dictionary (120) is accessible from the PLC (100) itself and is used to manage data obtained from the PLC (100).

[0038] At this time, if there are multiple user terminals (200), the object dictionary (110) can be implemented as many times as the number of user terminals (200). In addition, if the object dictionary (110) is implemented as a single unit, all objects corresponding to write signals received from multiple user terminals (200) can be created, and tagging can be performed on the objects for each user terminal (200) in order to classify the objects corresponding to multiple user terminals (200). Furthermore, in the embodiment of the present invention, the case where there is only one user terminal (200) will be described as an example.

[0039] The object dictionary (110) may include a first object (110a) through an nth object (110n), and each object may include object configuration information and an item container. The object configuration information may include information regarding an object ID, data type, offset, length, the number of items connected to the object, etc. The item container may include storage location information for each item connected to the object.

[0040] The item dictionary (120) can map data of the minimum information unit obtained from the PLC (100) to the first to nth items, respectively. At this time, the first to nth items each have different storage locations. When the item dictionary (120) receives storage location information of an item from the item container, it extracts the data mapped to the storage location corresponding to the storage location information and transmits it to the item container.

[0041] More specifically, the item container checks the storage location information of at least one item connected to each of the multiple objects. The item container checks the storage location of the item corresponding to the storage location information in the item dictionary (120) and requests the extraction of data mapped to the storage location. The item dictionary (120) extracts the data mapped to the storage location in accordance with the request and transmits it to the item container, and the item container performs the role of mapping the data received from the item dictionary (120) to the item connected to the object.

[0042] The object dictionary (110) of the PLC (100) may have at least one object already created. When the object dictionary (110) receives a read signal for an object already created from a user terminal (200), it checks the item container included in the object according to the read signal. The item container checks the storage location information for at least one item connected to the object, and receives data corresponding to the checked storage location information from the item dictionary (120) and maps it to the item.

[0043] The object dictionary (110) receives data from the item dictionary (120) and transmits it to the user terminal (200) which is mapped to an item connected to an object by an item container, so that the user terminal (200) can check the data corresponding to at least one item connected to an object.

[0044] In this way, the user terminal (200) can use the object dictionary (110) to check only the data corresponding to the item connected to the object created or modified by the user terminal (200) as needed, thereby ensuring flexibility to provide various forms of data to the user terminal (200) in accordance with user requests.

[0045] Additionally, while the PLC (100) is transmitting data corresponding to at least one item connected to an object created in the user terminal (200) by means of a read signal received from the user terminal (200), if an object write signal is received from the user terminal (200), the object dictionary (110) performs the creation of an object, deletion of an object created in the user terminal (200), or modification of an object created in the user terminal (200) according to the write signal.

[0046] After the creation, deletion, or modification of an object is performed, when the object dictionary (110) receives a read signal from the user terminal (200), it transmits data corresponding to an item connected to the created or modified object to the user terminal (200) so that the user terminal (200) can check the data corresponding to at least one item connected to the object. Additionally, when a read signal for a deleted object is received from the user terminal (200), it may transmit a message to the user terminal (200) indicating that the object has been deleted.

[0047] The user terminal (200) transmits an object write signal to the PLC (100) connected to the user terminal (200), and when the creation, deletion, or modification of an object corresponding to the object write signal is completed in the PLC (100), it transmits an object read signal to the PLC (100) to receive data from the PLC (100) corresponding to the object read signal, thereby allowing the operation of the PLC (100) to be verified.

[0048]

[0049] FIG. 2 is a flowchart for explaining a PLC control method that provides object communication according to an embodiment of the present invention.

[0050] Referring to FIG. 2, in step 201, the object dictionary (110) included in the PLC (100) receives an object write signal from a user terminal (200) connected to the PLC (100). At this time, the object write signal is a signal for creating an object composed of at least one item in the object dictionary (110), deleting an existing object, or modifying an existing object, and may be a signal transmitted by the user terminal (200) to the PLC (100). Additionally, the object write signal may be received during the operation of the PLC (100).

[0051] In step 203, the object dictionary (110) creates an object based on an object write signal received from the user terminal (200). At this time, the object dictionary (110) can create an object frame based on the write signal, including an object ID, the number of items included in the object, and an item container.

[0052] In step 205, the object dictionary (110) checks the storage location information of at least one item connected to the object from the item container. At this time, the storage location information may be storage location information for the storage location of the item stored in the item dictionary (120).

[0053] In step 207, the item dictionary (120) extracts data corresponding to the item corresponding to the requested storage location information from the item container and performs step 209. For example, if there are two items connected to an object, the item dictionary (120) can extract data corresponding to each item.

[0054] In step 209, the item dictionary (120) transmits the two extracted data to the item container, the item container maps the two received data to the storage location information of each item, and the object dictionary (110) completes the creation of the object based on this. That is, the two data extracted from the item dictionary (120) can be mapped to and stored in two items connected to the object, respectively.

[0055] In step 211, when the object dictionary (110) receives an object read signal from the user terminal (200) after the creation of the object is completed, it checks the data mapped to the object created in step 209. In step 213, the object dictionary (110) transmits the checked data to the user terminal (200).

[0056] In this way, the present invention enables the dynamic creation, deletion, or modification of a new object while ensuring continuous operation of the PLC (100) by having the user terminal (200) transmit an object write signal to the PLC (100) during operation of the PLC (100). Additionally, after the dynamic creation, deletion, or modification of the new object is completed, the user terminal (200) transmits an object read signal to the PLC (100) during operation of the PLC (100) to verify the data corresponding to the object that has been created, deleted, or modified. As a result, the availability of the PLC (100) can be maximized, and the flexibility to provide various forms of data in real time according to the user's request can be secured.

[0057] FIG. 3 is an illustrative diagram for explaining a method of performing a read operation of a pre-generated object for object communication according to an embodiment of the present invention.

[0058] Referring to FIG. 3, the object dictionary (110) may be a collection of service processing units according to the purpose of the user terminal (200), including a first object (110a) and a second object (110b) that have already been created. For example, the first object (110a) with object ID 0xC000 may be a Manage Communication Object, and the second object (110b) with object ID 0xC001 may be a Manage communication Item.

[0059] When looking at the object dictionary (110), it can be seen that the first object (110a) has an object ID of 0xC000 and that there are 3 items connected to the first object (110a), and the storage location information of the 3 items connected to the first object (110a) can be seen in the item container. That is, the storage location information of the 3 items identified in the item container can be seen as 0xC023-01, 0x100A-00, and 0x100D-00, respectively.

[0060] Additionally, it can be confirmed that the second object (110b) has an object ID of 0xC001 and that there are 5 items connected to the second object (110b), and the storage location information of the 5 items connected to the second object (110b) can be confirmed in the item container. That is, the storage location information of the 5 items confirmed in the item container can be confirmed as 0xC023-01, 0x100A-00, 0x100E-00, 0x100F-00, and 0x100C-00, respectively.

[0061] Accordingly, when the object dictionary (110) receives a read signal for the first object (110a) and the second object (110b) from the user terminal (200), it checks the object ID connected to the first object (110a) and the number of items connected to the first object (110a), and checks the location storage information of each item from the item container. The item container can retrieve data stored at a storage location corresponding to the identified storage location information among the multiple items stored in the item dictionary (120). In this way, when the retrieved data is mapped to the storage location information of each item included in the item container of the first object (110a), the object dictionary (110) transmits the corresponding data to the user terminal (200).

[0062] Likewise, after transmitting data related to the first object (110a) to the user terminal (200), the object dictionary (110) checks the object ID connected to the second object (110b) and the number of items connected to the second object (110b), and checks the location storage information of each item from the item container. The item container can retrieve data stored at a storage location corresponding to the identified storage location information among the multiple items stored in the item dictionary (120). In this way, when the retrieved data is mapped to the storage location information of each item included in the item container of the second object (110b), the object dictionary (110) transmits the corresponding data to the user terminal (200).

[0063] FIGS. 4 and FIGS. 5 are exemplary diagrams for explaining object frames of an object generated according to a write signal according to an embodiment of the present invention.

[0064] Referring to FIGS. 4 and FIGS. 5, FIG. 4a shows a frame of an object used to create a new object (hereinafter referred to as the third object) in a user terminal (200), and FIG. 4b shows the shape of the third object.

[0065] In the present invention, since the first object (110a) and the second object (110b) must be used to create a new object, the user terminal (200) can sequentially select the first object (110a) and the second object (110b) to create an object frame of the third object (110c).

[0066] At this time, the first object (110a) is an object that provides a service to manage communication objects as shown in Table 2 below, and the second object (110b) is an object that provides a service to manage communication items, so the user terminal (200) can create a third object (110c) using the first object (110a) and the second object (110b).

[0067] As shown in FIGS. 3 and 4b, the user terminal (200) can input 0x00001000, 0x25EA, and 0x0002, respectively, to offset 0, offset 1, and offset 2, which are three items connected to the first object (110a), in order to create a new third object with an object ID of 0x25EA and two items.

[0068] And, since the user terminal (200) has two items of the third object, it can input information for each item by using the second object (110b) that manages the items twice, such as reference numerals 110b-1 and 110b-2. For example, information related to the first item among the items to be included in the third object can be input by sequentially inputting 0x00001100, 0x25EA, 0x1100, 0x00, and 0x00 into offsets 0 to 4, which are five items connected to the second object corresponding to reference numeral 110b-1. In addition, information related to the second item among the items to be included in the third object can be entered by sequentially entering 0x00001100, 0x25EA, 0x1101, 0x00, and 0x01 into offsets 0 to 4, which are five items connected to the second object corresponding to drawing reference numeral 110b-1.

[0069] In this way, when a third object is created using the first object (110a) and the second object (110b) at the user terminal (200), the object dictionary (110) can be updated as shown in FIG. 5.

[0070] As shown in FIG. 5, when a read signal is received from a user terminal (200) after a third object (110c) is created in the object dictionary (110), the object dictionary (110) can retrieve data corresponding to the items connected to the corresponding objects in the order of the first object (110a) to the third object (110c) from the item dictionary (120) and then transmit it to the user terminal (200).

[0071] FIG. 6 is an illustrative diagram for explaining a method of modifying an object for object communication according to an embodiment of the present invention.

[0072] Referring to FIG. 6, the object ID of the fourth object (110d) created in the object dictionary (110) may be 0xC010 and may include five items. The five items connected to the fourth object (110d) may be 0x1010-00, 0x1011-00, 0x1012-00, 0x1013-00, and 0x1015-00.

[0073] When a write signal is received at the user terminal (200) to modify the fourth object (110d) with a fifth object (110e) which is connected only to three items, 0x1012-00, 0x1013-00, and 0x1015-00, out of the five items connected to the fourth object (110d), the object dictionary (110) can delete the fourth object (110d) and create a fifth object (110e) with an object ID of 0x245A.

[0074] The object dictionary (120) checks the storage location information of at least one item included in the item container according to the read signal of the user terminal (200). Based on the checked storage location information, the object dictionary (120) checks the data mapped to the storage location corresponding to the storage location information of the item connected to the fifth object (110e) among the items stored in the item dictionary (120). The object dictionary (120) maps the checked data to the storage location information of the corresponding item in the item container, 0x1012-00, 0x1013-00, and 0x1015-00, respectively. When data related to the item is mapped, the object dictionary (110) transmits the data to the user terminal (200).

[0075] At this time, the data, which is the minimum unit of information obtained from the PLC (100) mapped to the item ID constituting the item dictionary (120) shown in FIGS. 3 to 6, is as shown in Table 1 below, and the service processing name related to the object ID generated by the user terminal (200) is as shown in Table 2 below. Furthermore, it is to be clarified that Tables 1 and 2 are provided only for the purpose of explaining the present invention and are not necessarily limited thereto.

[0076] Item ID Data Item ID Data 0x1003-00Number of registered objects0x1011-00Subnet ID0x100A-00Communication object ID0x1012-00Station No0x100C-00Communication item Offsets0x1013-00IPv4 address0x100D-00Communication item Count0x1015-00MAC address0x100E-00Communication item ID0x1100-00Operation mode0x100F-00Communication sub ID0x1101-00Operation status0x1010-00Protocol version0xC023-01Command

[0077] Object ID Service Processing Name 0xC000Manage communication object 0xC001Manage communication item 0xC010Communication identifier

[0078] The embodiments of the invention disclosed in this specification and drawings are provided merely as specific examples to facilitate the explanation of the technical content of the invention and to aid in understanding the invention, and are not intended to limit the scope of the invention. Accordingly, the scope of the invention should be interpreted to include all modifications or variations derived based on the technical concept of the invention, in addition to the embodiments disclosed herein.

Claims

1. At least one user terminal; and A PLC comprising a plurality of dictionaries and performing the creation, deletion, or modification of an object including at least one item according to an object write signal received from the user terminal during operation based on at least one previously created object; A PLC control system providing object communication characterized by including 2. In Paragraph 1, The above PLC is, A PLC control system providing object communication characterized by transmitting data related to the created or modified object to the user terminal according to a read signal received from the user terminal.

3. In Paragraph 2, The above plurality of dictionaries are, A PLC control system providing object communication characterized by including an item dictionary and an object dictionary.

4. In Paragraph 3, The above object dictionary is, A PLC control system providing object communication characterized by being at least one previously generated object and a collection of objects generated or modified by the user terminal.

5. In Paragraph 4, The objects included in the above object dictionary are, Item container; A PLC control system providing object communication characterized by including 6. In Paragraph 5, The above item container is, A PLC control system providing object communication characterized by including storage location information of at least one item connected to an object included in the object dictionary above.

7. In Paragraph 6, The above item dictionary is, A PLC control system providing object communication characterized by mapping each of the multiple data identified in the above PLC to the storage location information of the corresponding item.

8. In Paragraph 7, The above item dictionary is, A PLC control system providing object communication characterized by extracting data mapped to storage location information of at least one item.

9. A PLC including multiple dictionaries receiving an object write signal from at least one user terminal during operation based on at least one pre-generated object; and A step in which the PLC performs the creation, deletion, or modification of an object including at least one item according to the object write signal; A PLC control method characterized by including

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