METHOD FOR ESTABLISHING ENERGY NETWORK COMMUNICATION USING OPC UA

Description

[0001] The invention relates to a method for user-specific retrieval of information stored on a cloud-enabled database, wherein the information on the database is available as different information types and / or in different data formats, wherein the user has an OPC UA client that is in communication with an OPC UA server, wherein the OPC UA server has a configuration module that is designed to create, aggregate and adapt information models, wherein the OPC UA server interacts with an application programming interface for the database, which application programming interface defines requirements and commands for accessing the database

[0002] Server-client systems that use the OPC UA ("Open Platforms Communication Unified Architecture") standard are known from the state of the art. This standard comprises an industrial machine-to-machine protocol that can be used across platforms. An OPC UA server using this standard provides data as structured information, which can be queried by an OPC UA client using this standard and used in a wide variety of applications.

[0003] With the buzzwords "Industrial Internet of Things (IIoT)" and "Industry 4.0," data from industrial plants is increasingly being stored in so-called cloud-enabled databases. A cloud-enabled database is defined as one that is compatible with cloud computing technology. In this case, cloud computing refers to the storage of information and access to the stored information via the internet.

[0004] Application programming interfaces (APIs) are used to access such a database and exchange data. These define the permitted commands and access types to a database. The API may require user authentication before access. This authentication is typically implemented using a key (a so-called "API key").

[0005] Field devices used in industrial plants are already known from the state of the art. Field devices are widely used in process automation technology as well as in manufacturing automation technology. Field devices essentially refer to all devices used close to the process and that provide or process-relevant information. Field devices are used to record and / or influence process variables. Measuring devices or sensors are used to record process variables. These are used, for example, for pressure and temperature measurement, conductivity measurement, flow measurement, pH measurement, level measurement, etc. and record the corresponding process variables such as pressure, temperature, conductivity, pH value, level, flow, etc. Actuators are used to influence process variables.These include, for example, pumps or valves that can influence the flow of a fluid in a pipe or the fill level in a container. In addition to the previously mentioned measuring devices and actuators, field devices also include remote I / Os, wireless adapters, and generally devices located at the field level.

[0006] A large number of such field devices are produced and distributed by the Endress+Hauser Group.

[0007] DE 10 2010 029 952 A1 describes a method and a system for integrating a field device into an automation technology network, comprising a plurality of field devices distributed in an automation system, which are connected to one another via at least one data bus on which a bus protocol runs, wherein access to the field devices is via a field access unit that communicates with at least one automation / integration platform and at least one web server of a service provider.

[0008] The publication by GHAZIVAKILI MOHAMMAD ET AL: "Industrial data-collector by enabling OPC-UA standard for Industry 4.0", 2018 14TH IEEE INTERNATIONAL WORKSHOP ON FACTORY COMMUNICATION SYSTEMS (WFCS), IEEE, June 13, 2018 (2018-06-13), pages 1–8, XP033369584, DOI: 10.1109 / WFCS.2018.8402364 describes the development of an OPC-UA-based architecture with a "collector" capable of collecting data from the shop floor and converting it into the OPC-UA standard to enable agile and effective vertical integration. A parallel communication mechanism is used.

[0009] US 2018 / 088548 A1 describes a method for process control of plants and plant control systems in an OPC UA-based machine-to-machine (M2M) network. A plant connected to the plant control system contains a plurality of interlocked elements of one or more operating units of the plant. The operation of an operating unit is controlled by the plant control system using the elements interlocked with the plant control system. The plant control system is accessible to an independent process control system in the machine-to-machine (M2M) network via one or more network interfaces, with messages containing signaling data and control commands being transmitted between the process control system and the plant control system.

[0010] The document "IEC TR 62541-1 ED3: OPC unified architecture - Part 1: Overview and Concepts", 65E / 605 / CD, IEC, 3, RUE DE VAREMBE, PO BOX 131, CH-1211 GENEVA 20, SWITZERLAND, June 29, 2018 (2018-06-29), pages 1-27, XP082014625, URL: http: / / www.iec.ch / cgibin / restricted / qetfile.pl / 65E 605e CD.pdf?dir=65E&format=pdf&tvpe= CDMile=605e.pd f describes the unified UPC architecture.

[0011] As of today, there is no simple way for a user to access granular cloud data via an OPC UA system.

[0012] Based on this problem, the invention is based on the object of presenting a method which allows data from a cloud-enabled database to be retrieved via an OPC UA system.

[0013] The object is achieved by a method for user-specific retrieval of information stored on a cloud-enabled database, wherein the information on the database is available as different information types and / or in different data formats, wherein the user has an OPC UA client that is in communication with an OPC UA server, wherein the OPC UA server has a configuration module that is designed to create, aggregate, and adapt information models, wherein the OPC UA server interacts with an application programming interface for the database, which application programming interface defines requirements and commands for accessing the database, comprising: Creating and loading a user-specific information model onto the OPC UA server using the configuration module, wherein the user-specific information model defines at least one piece of information or a plurality of pieces of information to be queried from the database; querying the information defined in the user-specific information model from the database using the application programming interface and transferring the information from the application programming interface to the OPC UA server; converting the queried information into OPC UA-compliant structural data; and transmitting the structural data from the OPC UA server to the OPC UA client.

[0014] The advantage of the method according to the invention is that structured, user-defined information from a cloud-based database can be made available to a user via their OPC UA system. The OPC UA server communicates with the database via the application programming interface. A provided information model informs the OPC UA server which information it should retrieve from the cloud. This retrieved information is then provided in structured information models (structural data) in standardized OPC UA format. The user connects to the OPC UA server via their OPC UA client and can retrieve the structural data provided.

[0015] It may be provided that the OPC UA server has several different application programming interfaces, whereby such an application programming interface enables communication with one or more databases.

[0016] The cloud-enabled database can be any type of database that can store any type of information.

[0017] It may be provided, but is not required, that during the creation of the user-specific information module, the availability of at least one of the information to be queried is checked in the database by means of a ping request to the database. H

[0018] According to the invention, during the creation of the user-specific information module, the availability of at least one of the pieces of information to be queried in the database is checked by means of a query telegram sent to the database via the application programming interface (API). After one of the pieces of information to be queried has been defined, a query telegram is sent via the application programming interface relating to the information to be queried. If the database contains information of the appropriate type, a positive response telegram is sent from the database. If no information of the appropriate type is stored in the database, a negative response telegram, or no response telegram, is sent from the database.

[0019] According to an advantageous embodiment of the method according to the invention, it is provided that the information to be queried is compiled as nodes in the user-specific information model according to the OPC UA specification NodeSet 2.0.

[0020] According to a preferred embodiment of the method according to the invention, the user-specific information model is created in a spreadsheet file format. For example, the specific information model is available in an Excel file format.

[0021] According to an advantageous embodiment of the method according to the invention, the information stored in the database is information generated by components of an automation system. This is a production automation or process automation system in which at least one product of a predetermined quality and quantity is automatically produced from at least one reactant.

[0022] Alternatively, any information of any type can be stored in the database, for example weather data, inventory data, etc.

[0023] According to a preferred embodiment of the method according to the invention, it is provided that the components are field devices and the information is at least information from at least one of the following categories: Process values ​​collected by the field devices; status or diagnostic information of the field devices; information regarding the geographical location of the field devices; device identifications of the field devices; order status of the field devices with the respective device manufacturer.

[0024] According to an advantageous embodiment of the method according to the invention, it is provided that before querying the information defined in the user-specific information model from the database, a key is sent to the application programming interface by means of the OPC UA server and checked for validity, and wherein the information defined in the user-specific information model is only queried if the validity of the key can be successfully checked. The invention is explained in more detail with reference to the following figures.

[0025] Fig. 1 : an embodiment of the method according to the invention.

[0026] Shown is an OPC UA system consisting of an OPC UA server SE (hereinafter referred to as "server") and several OPC UA clients CL (hereinafter referred to as "clients"), which communicate via a TCP / IP network. The clients CL are located on the user side and are each part of user-specific applications AW. These applications include, for example, a user database, one or more application programs, particularly designed for information processing, and / or a human-machine interface (HMI) or a SCADA system.

[0027] The user is the operator of an automation system A. In such a modern system A, field devices F1, F2, F3, F4 are usually connected to higher-level PLC units via communication networks such as field buses FB (Profibus ®< , Foundation ®< Fieldbus, HART ®< , etc.). The higher-level units are control units such as a programmable logic controller or a PLC (Programmable Logic Controller). The higher-level PLC units are used, among other things, for process control and for commissioning the field devices F1, F2, F3, F4. The measured values ​​recorded by the field devices F1, F2, F3, F4, in particular by sensors, are transmitted via the respective field bus FB to one (or possibly several) higher-level PLC units, which may further process the measured values ​​and forward them via a data network D1 to the control center, consisting of several workstation PCS WS1, WS2, of system A.The control center serves for process visualization, process monitoring, and process control via the higher-level PLC units. In addition, data transmission from the higher-level PLC unit via the fieldbus (FB) to the field devices F1, F2, F3, and F4 is required, particularly for configuring and parameterizing field devices F1, F2, F3, and F4, as well as for controlling actuators.

[0028] In addition, a so-called Edge Device ED is connected to the fieldbus FB. The Edge Device ED is designed to listen to the information transmitted via the fieldbus FB by the field devices F1, F2, F3, and F4, process it if necessary, and transmit it via the internet to a cloud-enabled database DB. The database DB stores this information along with other field device-relevant information. Examples of field device-relevant information stored in the database include: Process values ​​collected by the field devices F1, F2, F3, F4; status or diagnostic information of the field devices F1, F2, F3, F4; information regarding the geographical location of the field devices F1, F2, F3, F4; device identifications of the field devices F1, F2, F3, F4, for example, their serial number, their manufacturer, or their order code; order status of the field devices with the respective device manufacturer, as well as additional information calculated from this information, which is calculated in particular by applications running on the database DB.

[0029] In order for the user to be able to use the information stored in the database DB on their OPC UA system, it must be retrieved from the database DB in an OPC UA-compliant manner. For this purpose, the server SE has a configuration module KM into which one or more user-specific information models IM can be loaded. Such an information model IM is typically available in a spreadsheet file format and defines which information IN should be queried from the database DB by the server SE. The connection between the server SE and the database DB is controlled by an application programming interface, which defines access and the permitted operator control telegrams to or for the database DB.

[0030] After the user has authenticated to the database DB, the server SE processes the information model successively and receives the information defined in it from the database DB. The information model IN is populated with the retrieved information and made available as OPC UA-compliant structural data. This structural data can then be retrieved by the clients CL and further processed or used via the applications IG.

[0031] The Fig. 1 The process shown is intended as an example. In addition to the described database, which contains information about an automation system A, any database with any information type can be used. List of reference symbols

[0032] AAutomation technology system APIApplication programming interface CLOPC UA Client D1Data network DBDatabase EDEdge Device F1, F2, F3, F4Field devices FBFieldbus AWUser applications (OPC UA Client) INInformation inUser-specific information model KMConfiguration module SEOPC UA Server PLCHigher-level unit WS1, WS2Workstation PC

Claims

1. Method for user-specific acquisition of information (IN) which is stored on a cloud-capable database (DB), the information (IN) being present on the database (DB) as different types of information and / or in different data formats, the user having an OPC UA client (CL) which is in a communication link with an OPC UA server (SE), the OPC UA server (SE) has a configuration module (KM), which configuration module (KM) is designed to create, aggregate and adapt information models, the OPC UA server (SE) interacting with an application programming interface (API) of the database (DB), which application programming interface (API) defines requests and commands for accessing the database (DB), comprising: - creating and loading a user-specific information model (IM) onto the OPC UA server (SE) by means of the configuration module (KM), the user-specific information model (IM) defining at least one information item (IN) or a plurality of information items (IN) which are to be queried from the database (DB); - Querying the information (IN) defined in the user-specific information model (IM) from the database (DB) by means of the application programming interface (API) and passing the information (IN) from the application programming interface (API) to the OPC UA server (SE); - Converting the queried information (IN) into OPC UA-compliant structural data; and - transmitting the structure data from the OPC UA server (SE) to the OPC UA client (CL), characterized in that, in the course of creating the user-specific information module (IM), the availability of at least one of the items of information (IN) to be queried on the database (DB) is checked by means of a request telegram sent to the database (DB) via the application programming interface (API).

2. Method accordingto claim 1, wherein the information (IN) to be queried is compiled as nodes in accordance with the OPC UA specification NodeSet 2.0 in the user-specific information model (IM).

3. Method according to at least one of the previous claims, wherein the user-specific information model (IM) is created in a spreadsheet file format.

4. Method according to at least one of the previous claims, wherein the information (IN) stored on the database (DB) is information that is created by components of a plant (A) of automation technology.

5. Method according to claim 5, wherein the components are field devices (F1, F2, F3, F4) and wherein the information (IN) is information from at least one of the following categories: - process values collected by the field devices (F1, F2, F3, F4) - status or diagnostic information of the field devices (F1, F2, F3, F4) - information regarding the geographical location of the field devices (F1, F2, F3, F4) - device identifications of the field devices (F1, F2, F3, F4) - Order status of the field devices (F1, F2, F3, F4) from the respective device manufacturer.

6. A method according to at least one of the previous claims, wherein, before the information (IN) defined in the user-specific information model (IM) is queried from the database (DB), a key is sent to the application programming interface (API) by means of the OPC UA server (SE) and checked for validity, and wherein the information (IN) defined in the user-specific information model (IM) is queried only if the validity of the key can be successfully checked.