Ethernet-based safety control PLC device

Abstract

The present invention relates to a PLC device related to functional safety. The safety control PLC device according to the present invention comprises a plurality of communication modules and a safety control module for controlling same, wherein: the safety control module satisfies a predetermined standard for functional safety and controls the plurality of communication modules; and the communication modules support a RAPIEnet network and constitute each network as a ring network, thereby facilitating adding or expanding of a conventional PLC network, and implementing a stable safety control function.

Description

Ethernet-based safety control PLC device

[0001] The present invention relates to a PLC device configured as a communication network, and in particular to safety control network technology that provides safety functions.

[0002] A PLC (Programmable Logic Controller) is a control device used for automatic control or monitoring in factories. It receives sensor values, performs logical operations according to a user's pre-set program, and controls externally connected devices based on the results.

[0003] Recent control systems tend to utilize network-based distributed control systems to enable flexible responses to installation, management, and expansion. Consequently, PLC systems are configured with various communication modules to allow connection to multiple networks.

[0004] Recently, such network-based distributed control is widely used in the field of in-line control for finished vehicles. In-line control for finished vehicles is characterized by being composed of four main lines—press, body, painting, and assembly—and being modularized by field.

[0005] Control of each line is performed by a high-performance PLC responsible for main functions, and each I / O and sub-PLC is interconnected via a network.

[0006] Manufacturing sites configured with such PLC networks require the use of safety equipment for the safety of workers. The safety equipment must satisfy safety standards (IEC 61508, IEC 62061, ISO13849-1) and can be configured using a safety network (IEC 61784-3).

[0007] Conventional safety controllers have limitations in that they are connected to safety equipment only through safety I / O connected to the controller, or even if they provide network functions, they operate with only a single network, making expansion impossible even when the system grows.

[0008] The inventors of the present invention have been making research efforts to solve the problems of safety control devices of conventional PLC devices. Through extensive efforts to provide a safety control device capable of network expansion and division according to user needs by using a RAPIEnet network, the present invention has been completed.

[0009] The objective of the present invention is to provide a safety controller having a flexible network environment capable of network expansion and division.

[0010] In addition, another objective of the present invention is to provide a safety controller that allows a safety network to be added to a system using an existing RAPIEnet network without additional network installation or changes to network lines by using the RAPIEnet network as the black channel of the safety network.

[0011] Meanwhile, other unspecified objectives of the present invention will be further considered to the extent that they can be easily inferred from the following detailed description and effects.

[0012] The safety control PLC device according to the present invention is,

[0013] It includes a plurality of communication modules supporting an Ethernet network; and a safety control module for controlling the plurality of communication modules to perform a safety control function of a predetermined standard, wherein each of the plurality of communication modules forms an independent network.

[0014] The above safety control module is characterized by being provided in a plurality of units to control each of the plurality of communication modules.

[0015] The above communication module is characterized as being a RAPIEnet (Real-time Automation Protocols for Industrial Ethernet) network support module.

[0016] The independent network formed by the above communication module is characterized as being a ring network.

[0017] The above safety control module is characterized by further including a RAPIEnet network support function.

[0018] The above safety control module is characterized by transmitting the same functional safety message multiple times when transmitting a functional safety message through the communication module.

[0019] A safety control PLC device according to the present invention, according to another embodiment of the present invention, is,

[0020] It is characterized by including a plurality of safety control modules that perform safety control functions of predetermined specifications and include network communication functions, wherein each of the plurality of safety control modules forms an independent network.

[0021] A safety control PLC device according to the present invention, according to another embodiment of the present invention, is,

[0022] A communication module supporting an Ethernet network; a first safety control module for controlling the communication module to perform a safety control function of a predetermined standard; and a second safety control module for performing a safety control function of a predetermined standard that includes a network communication function, wherein each of the communication module and the second safety control module forms an independent network.

[0023] According to the present invention, there is an effect of being able to expand or add configurations related to functional safety without adding separate network facilities or lines while satisfying standards regarding functional safety.

[0024] In addition, by enabling multiple functional safety sub-networks to be processed in a single functional safety system, there is an advantage in that management, including the installation and maintenance of functional safety networks, can be carried out efficiently.

[0025] Meanwhile, it should be added that even if an effect is not explicitly mentioned here, the effects described in the following specification and the provisional effects expected by the technical features of the present invention are treated as described in the specification of the present invention.

[0026] FIG. 1 is a schematic structural diagram of a safety control PLC device according to a preferred embodiment of the present invention.

[0027] FIG. 2 is a schematic structural diagram of a safety control PLC device according to another preferred embodiment of the present invention.

[0028] FIG. 3 is a schematic structural diagram of a safety control PLC device according to another preferred embodiment of the present invention.

[0029] FIG. 4 is a schematic structural diagram of a safety control PLC device according to another preferred embodiment of the present invention.

[0030] FIG. 5 is a schematic flowchart of a safety message transmission method of a safety control PLC device according to a preferred embodiment of the present invention.

[0031] Figure 6 is a schematic diagram of a safety function network according to the prior art.

[0032] ※ It should be noted that the attached drawings are provided as examples for reference to help understand the technical concept of the present invention, and the scope of the rights of the present invention is not limited by them.

[0033] The national research and development projects that supported this invention are as follows.

[0034] [Project ID] 2410004419

[0035] [Assignment No.] 20022994

[0036] [Ministry Name] Ministry of Trade, Industry and Energy

[0037] [Name of Project Management (Specialized) Agency] Korea Institute of Industrial Technology Planning and Evaluation

[0038] [Research Project Name] Development of Technology for the Machinery and Equipment Industry

[0039] [Research Project Title] Advanced Standard-Based Controllers and Development of Digital Twin-Based Controller Performance Verification Technology

[0040] [Executing Organization Name] Korea Electronics & Technology Institute / Joint R&D Organization Name: LS ELECTRIC

[0041] [Research Period] 2023.04.01 ~ 2025.12.31

[0042] Hereinafter, with reference to the drawings, we will examine the configuration of the present invention as guided by various embodiments thereof and the effects derived therefrom. In describing the present invention, detailed descriptions of related known functions are omitted if they are deemed obvious to a person skilled in the art and could unnecessarily obscure the essence of the invention.

[0043] Terms such as 'first' and 'second' may be used to describe various components, but said components should not be limited by said terms. These terms may be used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, 'first component' may be named 'second component,' and similarly, 'second component' may be named 'first component.' Furthermore, singular expressions include plural expressions unless the context clearly indicates otherwise. Unless otherwise defined, terms used in the embodiments of the present invention may be interpreted in the sense commonly known to those skilled in the art.

[0044] Hereinafter, with reference to the drawings, we will examine the configuration of the present invention as guided by various embodiments of the present invention and the effects derived therefrom.

[0045] Figure 6 shows an example of a functional safety network configuration according to the prior art.

[0046] The safety control PLC device (500) that performs safety control functions is a PLC device capable of performing safety functions that satisfy safety standards.

[0047] Safety functions must be implemented in compliance with safety regulations of each country or according to on-site requirements for a safe working environment. To implement safety functions, safety controllers and safety I / O interfaces must be installed.

[0048] Safety controllers and I / O are limited to products developed based on a separate safety function development methodology and that have obtained safety certification. To satisfy the Safety Integrate Level, safety controllers and I / O must be merged into existing devices to form a separate network or require additional wiring. This is because it is difficult to prove if the failure rate fluctuates due to the influence of existing networks or wiring.

[0049] The safety control PLC device (500) is connected to safety function-related PLC modules, such as a safety input module (510) and a safety output module (520), to implement safety functions using network functions such as EtherCAT.

[0050] The safety control PLC device (500) can perform not only safety-related functions but also general PLC device functions. Since network expansion is not possible, safety-related functions and general functions must be managed together in a single network.

[0051] In this case, if the safety control PLC device (500) can only operate one network, there is a problem in that it is difficult to handle situations where the system needs to be expanded according to the user's needs, or where the network needs to be separated and operated by work unit or function.

[0052] In addition, installing additional networks or wiring to install safety controllers and safety I / O presents not only cost issues but also the problem of having to accept reduced productivity because it causes the control lines that are already installed and operating normally to be shut down for a long time.

[0053] FIG. 1 is a schematic structural diagram of a safety control PLC device according to a preferred embodiment of the present invention for solving the problems of such prior art.

[0054] The safety control PLC device (100) according to the present invention may be composed of a base module (110) and modules mounted thereon.

[0055] Modules mounted on the base module (110) may include a power module (120), a CPU module (130), a safety control module (140), and a plurality of communication modules (150, 160).

[0056] The power module (120) supplies power to the modules mounted on the base module (110).

[0057] The power module (120) converts AC or DC power and provides power of a size and shape suitable for the module mounted on the base module (110). Depending on the function and capacity, it may be configured as an internal or external module.

[0058] The CPU module (130) is responsible for the overall control of the modules mounted on the base module (110).

[0059] The CPU module (130) executes a user program (LD, etc.), inputs conditions and data of input data (sensor data, etc.) into the user program, and transmits the result to the output module. It performs operations on all control data, and thus determines the performance of the system.

[0060] The safety control module (140) controls the communication modules (150, 160) to implement and control safety functions.

[0061] The safety control module (140) must satisfy safety standards (IEC 61508, IEC 62061, ISO13849-1) to implement safety functions and can be configured using network standards (IEC 61784-3) to implement safety functions.

[0062] The safety control module (140) can process or compute safety data and can receive only safety data as input and output it through the safety output module. The safety data is not mixed with non-safety data. In addition, it is equipped with a function to switch to a safety mode in an emergency according to safety standards.

[0063] The communication module (150, 160) forms a network to transmit safety data to the safety control module (140) or transmits it from the safety control module (140) to the safety input / output module.

[0064] The safety network standard IEC 61784-3 can be implemented using the Black channel approach, which means that no specific channel (White channel) is defined to implement the safety network standard. In other words, it means that any network can be used.

[0065] Accordingly, the communication module (150, 160) of the safety control PLC device according to the present invention can use the RAPIEnet (Real-time Automation Protocols for Industrial Ethernet) network as a network standard.

[0066] Since the RAPIEnet network is characterized by being connected to all control elements, when adding RAPIEnet network-based safety function devices, new safety function devices or general devices can be added without the need for a separate network or wiring.

[0067] The safety control module (140) can implement safety functions by controlling the first communication module (150) and the second communication module (160).

[0068] Unlike conventional technology, the safety control module (140) is connected to a plurality of communication modules (150, 160), and since the first communication module (150) and the second communication module (160) can each form a network, there is an advantage in that the network can be operated separately by function or by work unit.

[0069] Network expansion, that is, when an additional network is required, can be achieved by adding a communication module to configure a new network, thereby enabling network expansion without affecting the existing network. This is because the safety control PLC device (100) according to the present invention uses a RAPIEnet network to connect all control elements to each other.

[0070] The first communication module (150) may be a master RAPIEnet controller.

[0071] The first communication module (150) transmits output data of the CPU module (130) to remote devices via PLC I / O (1, 2) or, conversely, transmits data from remote devices to the CPU module (130). It monitors the operating status of remote devices and monitors the RAPIEnet network to generate alarms and events, and these alarms and events can be transmitted to the CPU module (130) or sent to a user monitoring device such as an HMI or SCADA.

[0072] The first communication module (150) can distinguish between safety data and non-safety data and provide services. In the case of safety data, it can be transmitted to the safety control module (140) without interpreting or analyzing the value, and manages a report function regarding service quality related to the function of transmitting to the RAPIEnet remote device that manages safety I / O.

[0073] The first communication module (150) can provide multiple transmission options for safety data, which can provide a more robust communication environment in a noisy environment.

[0074] Figure 5 is a schematic flowchart of this safety message multiplexing method.

[0075] The safety control module (140) transmits a safety message request through the first communication module (150) (S110), and the first communication module (150) transmits it multiple times (S120).

[0076] Generally, periodic data (data updated at fixed intervals) is transmitted during the next transmission cycle, so multiple transmissions are not performed. Similarly, for retransmittable data—for example, when a timeout is used to determine whether retransmission is necessary—multiple transmissions are not performed.

[0077] However, since safety data cannot be retransmitted due to safety standards, multiple transmissions can be performed to compensate for this, thereby providing a robust communication environment.

[0078] Therefore, such multiple transmissions are recommended by manufacturers of devices that implement safety functions and can be selected by considering the influence of the control environment (noise, communication load, etc.).

[0079] To transmit a safety message multiple times, information identifying that the safety message has been transmitted multiple times must be included. This information may be included in the header of the Ethernet frame or in the safety message itself.

[0080] The PLC I / O (1) that receives multiple safety messages receives response messages from connected remote devices and transmits them to the first communication module (150) (S130), and the first communication module (150) transmits the safety message response to the safety control module (140) (S140).

[0081] However, even if the first message is not delivered while multiple messages are being transmitted, the second message can be delivered (S160), and the safety message is normally delivered to the safety control module (140) (S180).

[0082] Therefore, it is effective in maintaining a robust communication environment even in environments where message transmission is not smooth, such as noisy environments. This is because the probability of all multiple Ethernet frames failing due to noise is not high.

[0083] Figure 5 illustrates an example of sending a safety message in duplicate, but it may also be possible to send it in triple or more multiple times.

[0084] The second communication module (160) transmits output data received from the first communication module (150) to the generic output module and transmits data received from the generic input module to the first communication module (150). It can be responsible for controlling generic I / O and can maintain and manage generic I / O control results to provide them to the first communication module (150) when needed.

[0085] The second communication module (160) can also provide services by distinguishing between safety data and non-safety data. In the case of safety data, it can be transmitted to the safety control module (140) or the first communication module (150) without interpreting or analyzing the value, and manages a report function regarding the service quality related to the function of transmitting to the RAPIEnet remote device that manages safety I / O.

[0086] The second communication module (160) can also provide multiple transmission options for safety data.

[0087] The first communication module (150) and the second communication module (160) both form a ring network with the PLC I / O modules (1, 2, 3, 4), and the network can use the RAPIEnet network as previously described.

[0088] Both safety function I / O and general I / O can be connected to the PLC I / O modules (1, 2, 3, 4).

[0089] The safety function I / O is used to output data requested from the safety control module (140) or to respond to the safety control module (140) with safety data. The safety function I / O satisfies safety standards and can support safety network functions. Additionally, it can switch to a safety mode in an emergency according to the functional safety standards.

[0090] General I / O performs the general input / output functions of a PLC device, carrying out various electrical, electronic, and physical input / output functions, including digital and analog input / output.

[0091] The first communication module (150) and the second communication module (160) can form a ring network while supporting the RAPIEnet network.

[0092] When configured as a ring network, even if a problem occurs with the first PLC I / O (1), the second PLC I / O (2) can be accessed through the opposite path, so there is an advantage in that the stability of the network is increased.

[0093] FIG. 2 is a schematic structural diagram of a safety control PLC device according to another preferred embodiment of the present invention.

[0094] A safety control PLC device (200) according to another embodiment of the present invention may be composed of a base module (210) and modules mounted thereon.

[0095] Modules mounted on the base module (210) may include a power module (220), a CPU module (230), a first safety control module (240), a second safety control module (250), and a plurality of communication modules (260, 270).

[0096] Unlike the example in Fig. 1, the safety control module is composed of multiple modules and can control each of the communication modules.

[0097] The first safety control module (240) controls the first communication module (260), and the second safety control module (250) can control the second communication module (270).

[0098] By using multiple safety control modules to control each of the multiple communication modules, it is possible to manage and control each sub-network separately.

[0099] The first communication module (260) and the second communication module (270) may both be communication modules that support a RAPIEnet network, and each communication module may configure a separate sub-network as a ring network.

[0100] FIG. 3 is a schematic structural diagram of a safety control PLC device according to another preferred embodiment of the present invention.

[0101] A safety control PLC device (300) according to another embodiment of the present invention may be composed of a base module (310) and modules mounted thereon.

[0102] Modules mounted on the base module (310) may include a power module (320), a CPU module (330), a first safety control module (340), a second safety control module (350), etc.

[0103] Unlike the examples in Fig. 1 or Fig. 2, in the example in Fig. 3, the safety control module and the communication module are configured as separate modules, but in the example in Fig. 3, the safety network is configured only by the safety control module without the communication module.

[0104] To this end, the safety control module (340, 350) may include communication functions, and in particular, may support RAPIEnet network functions.

[0105] The safety control module (340, 350) has the advantage of being able to simplify the PLC device by including the function of the communication module.

[0106] The safety control modules (340, 350) include communication functions so that each safety control module can form a network, and in particular, by forming a ring network, there is an advantage of being able to operate more stably in the event of an error or failure.

[0107] FIG. 4 is a schematic structural diagram of a safety control PLC device according to another preferred embodiment of the present invention.

[0108] A safety control PLC device (400) according to another embodiment of the present invention may be composed of a base module (410) and modules mounted thereon.

[0109] Modules mounted on the base module (410) may include a power module (420), a CPU module (430), a first safety control module (440), a second safety control module (450), and a first communication module (460).

[0110] Unlike the example in FIG. 3, the safety control PLC device (400) of FIG. 4 may include a first safety control module (440) that includes a communication function and a second safety control module (450) that does not include a communication function.

[0111] As previously discussed, the first safety control module (440) can form an independent network by supporting RAPIEnet network functions, and in particular, when configured as a ring network, it can form a network that can respond more reliably to errors or failures.

[0112] The second safety control module (450) can control the first communication module (460). The first communication module (460) may be a communication module that supports a RAPIEnet network and may also form a ring network.

[0113] By configuring the PLC device with a safety control module that requires a separate communication module in addition to the safety control module that includes communication functions, safety functions can be added without interrupting the network by simply adding the safety control module without replacing the configuration of the network composed of communication modules that support the conventional RAPIEnet network.

[0114] In other words, it has the advantage of being able to expand the network by adding safety functions without modifying the existing network.

[0115] According to the safety control PLC device of the present invention including the safety functions as described above, by including a RAPIEnet communication module capable of configuring a ring network, control modules and I / Os including safety control functions can be expanded and added to existing systems without installing separate network facilities or lines, and accordingly, there is an advantage in that different sub-networks required by the user can be configured into a single safety system.

[0116] The scope of protection of the present invention is not limited to the description and expression of the embodiments explicitly described above. Furthermore, it is added once again that the scope of protection of the present invention cannot be limited by obvious changes or substitutions in the technical field to which the present invention belongs.

Claims

1. Multiple communication modules supporting Ethernet networks; and A safety control module for controlling the above plurality of communication modules to perform a safety control function of a predetermined standard; Includes, A safety control PLC device characterized in that each of the above plurality of communication modules forms an independent network.

2. In Paragraph 1, A safety control PLC device characterized in that the safety control module is provided in a plurality of units to control each of the plurality of communication modules.

3. In Paragraph 1, A safety control PLC device characterized in that the communication module is a RAPIEnet (Real-time Automation Protocols for Industrial Ethernet) network support module.

4. In Paragraph 1, A safety control PLC device characterized in that the independent network formed by the above communication module is a ring network.

5. In Paragraph 1, A safety control PLC device characterized by the above safety control module further including a RAPIEnet network support function.

6. In Paragraph 1, A safety control PLC device characterized in that the above safety control module transmits the same functional safety message multiple times when transmitting a functional safety message through the communication module.

7. A plurality of safety control modules that perform safety control functions of predetermined specifications and include network communication functions; Includes, A safety control PLC device characterized in that each of the above plurality of safety control modules forms an independent network.

8. Communication module supporting Ethernet network; A first safety control module for controlling the above communication module to perform a safety control function of a predetermined standard; and A second safety control module that includes network communication functions and performs safety control functions of predetermined specifications; Includes, A safety control PLC device characterized in that each of the above communication module and the second safety control module forms an independent network.

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