CN105812253A - OPC UA data service gateway device and implementation method thereof - Google Patents

Abstract

The present invention relates to an OPC UA data service gateway device and its implementation method. The method and device are used to implement an embedded OPC UA server under the application of the industry standard communication protocol OPC UA, and can periodically collect instruments, PLCs, etc. Relevant information data of different types of field devices, map these devices into the OPC UA address space, establish corresponding device models and device relationship models, and realize the identification and management of field devices. At the same time, in order to enable the OPC UA client Interact with the server and apply the OPC UA transaction management mechanism, so that the OPC UA server can provide services such as monitoring, reading and writing, and querying for the client. The gist of the present invention is to use the OPC UA protocol to realize a device interface that supports multiple wireless communication protocol standards technology, and has low power consumption and easy-to-extend service adapter hardware as the carrier, so that you don't need to care about the underlying protocol and implementation when performing automatic control.

Description

An OPC UA data service gateway device and its implementation method

technical field

The invention relates to an OPCUA data service gateway, in particular to an OPCUA data service gateway device and an implementation method thereof, which are used to design an embedded service adapter according to the standard protocol OPCUA.

Background technique

With the rapid development of today's industry, the continuous improvement of production efficiency requirements, and the rapid development and integration of control technology, information technology and network technology, the demand for data collection and long-distance transmission in different industrial fields is also increasing. Due to the large number of manufacturers of industrial equipment, the data formats and types generated by the equipment produced by different manufacturers and applied in different industrial occasions are also very different. Most of the existing data gateways complete data acquisition through bus technologies such as RS485/CAN/ModBus, and only support a single type of acquisition terminal, and the compatibility of multiple types of metering devices is poor or even incompatible; A microprocessor with a clock frequency of less than 100MHz can support fewer bus interfaces, so the number of metering terminal devices supported by a single gateway cannot meet the needs of use. To sum up, on the basis of satisfying the basic data collection functions, the data gateway should add more functions and designs for continuous improvement.

OPCUA is a supplement to the already used OPC industry standard, providing more important features, including platform independence, scalability, high reliability and the ability to connect to the Internet. OPCUA no longer relies on DCOM, but is based on a service-oriented architecture (SOA). OPCUA is easier and more flexible to use, and realizes the transmission of raw data and preprocessed information from the manufacturing level to the production planning or ERP level. Now, OPCUA has become a bridge between the enterprise layer and embedded automatic components independent of Microsoft, UNIX or other operating systems.

In the prior art, the service adapter designed according to the standard protocol OPCUA is implemented by a host computer, which has poor flexibility in use, is difficult to integrate with field devices, and consumes a lot of energy.

The objects and related information provided by the OPCUA server in the host computer to the client are related to the address space of the server, providing a consistent and complete address space and service model. This allows a single OPCUA server to unify data, alarms and events, and historical information into its address space, and provide interfaces for them with a set of unified services, which also include a unified security model. The OPCUA server integrates independent address spaces into a unique address space. The client accesses real-time data, historical data, etc. are all accessed in an integrated address space, and at the same time realizes data access, historical data access, control commands, Interactive communication of complex data.

The upper computer provides a large storage space for the OPCUA server, and the main frequency of the upper computer also provides a higher processing speed for the OPCUA server, and the system platform of the upper computer greatly reduces the workload of developers. However, since the upper computer cannot be integrated with the equipment, it cannot process the field equipment information data in real time. Moreover, the compilation process has undergone different levels of evolution, and the embedded hardware environment allows the server to directly interact with the underlying field devices through high-speed C compilation, and the cost of its implementation is also very low compared to the upper computer, which is more suitable for industrial occasions The large-scale production can improve the production efficiency of the production line in an all-round way.

For the needs of real-time data processing of field devices, it has great advantages to realize the OPCUA service adapter in an embedded way.

Contents of the invention

Aiming at the above-mentioned deficiencies in the prior art, the technical problem to be solved in the present invention is to overcome the defects of existing gateways, provide an OPCUA data service gateway device and its implementation method, which can not only integrate different formats and types of industrial sites The data is collected and transmitted in real time, and the data can also be encapsulated into an OPCUA information model, and transmitted to the upper computer OPCUA client through Ethernet in real time, so as to store, access and analyze the data, and then achieve the purpose of real-time monitoring of the industrial site ; Implemented with embedded OPCUA technology, it provides a data acquisition technology that does not depend on the underlying communication protocol, and provides WebService services to users, so that different types of OPCUA clients can access the server. Compared with traditional OPC, it has more High scalability and flexibility

The technical scheme that the present invention adopts for realizing the above object is: a kind of OPCUA data service gateway device, comprises:

Serial port to network server unit, one end is connected to the main control unit, and the other end is used to connect to the field device, which is used to realize the two-way conversion between the serial port data and Ethernet data of the main control unit, and then realize the data transmission between the field device and the main control unit ;

The Ethernet interface unit is connected with the Ethernet control unit and the upper computer, and is used to establish a communication connection between the main control unit and the upper computer, and provides a channel for data transmission between the two;

The Ethernet control unit is connected with the Ethernet interface unit and the main control unit, controlled by the main control unit, and used to control the work of the Ethernet interface and the data transmission between the main control unit and the upper computer;

The externally expanded SRAM storage unit is connected with the main control unit to store OPCUASDK and provide storage space for the collected data;

The main control unit, integrated in the communication module of the field device, is used to control the work of the serial port to network server unit, Ethernet control unit, external SRAM storage unit, control buttons and indicator lights, and its internal SRAM and FLASH are used as the first level Cache and flash memory, used to provide support for the operation of the program;

Control button, connected with the main control unit, used to wake up the gateway in standby mode or reset the gateway when the internal program encounters problems;

The indicator light unit is connected with the main control unit and is used to indicate the working state of the gateway;

The power supply unit is used to convert the 220V AC voltage into the 3.3V DC working voltage required by all the above units.

The serial port-to-network server unit includes a TCP/IP serial port protocol conversion module, its peripheral circuits, and an Ethernet interface.

The Ethernet control unit is composed of an Ethernet PHY controller chip and its peripheral circuits.

The main control unit is composed of STM32F407 series MCU chip and its peripheral circuits.

The power supply unit includes a power connector, a step-down switching power supply module, a filter circuit, a circuit protection, and a linear voltage regulator, and the power connector is located at the edge of the circuit board.

A method for realizing an OPCUA data service gateway device, comprising the following steps:

Set the node name of the connected field device through the main control unit, and describe the static attribute and address ID of each field device;

When the host computer OPCUA client initiates the monitoring service, the main control unit obtains the dynamic attributes of the field device through the serial port/Ethernet;

The serial port/Ethernet outputs the obtained dynamic attributes to the corresponding node of the OPCUA server;

The OPCUA client calls the read service inside the OPCUASDK to obtain the attributes of the corresponding nodes in the OPCUA server.

A method for realizing an OPCUA data service gateway device, comprising the following steps:

Set the node name of the connected field device through the main control unit, and describe the static attribute and address ID of each field device;

The main control unit outputs the obtained dynamic attributes to the cache of the OPCUA server through the serial port/Ethernet, and waits for the OPCUA client to initiate the service;

When the host computer OPCUA client initiates the monitoring service, the main control unit assigns the data in the cache to the attributes of the corresponding node of the OPCUA server;

The OPCUA client calls the read service inside the OPCUASDK to obtain the attributes of the corresponding nodes in the OPCUA server.

Also includes:

When the attribute value of the field device exceeds the threshold set by the OPCUA server, stop the reading service inside OPCUASDK, and transmit the attribute value to the OPCUA client through the alarm mechanism inside OPCUASDK.

The dynamic data obtained by the OPCUA client is inserted into a pre-configured database for historical information query of field device data.

It also includes: the OPCUASDK generates the unique serial number of the OPCUA server and provides it to the OPCUA client to identify the uniqueness of the OPCUA server.

The present invention has the following advantages and beneficial effects:

1. The wireless communication device based on the WIA-PA protocol is used for data reception and collection, which is suitable for complex industrial environments. Its comprehensive flexibility in time, frequency and space makes this relatively simple and effective The protocol has embedded self-organization and self-healing capabilities, which greatly reduces the complexity of installation and ensures long-term and predictable performance of the wireless network; it can realize point-to-point, point-to-multipoint, and multipoint-to-multipoint devices Transparent transmission of data between them; it can form a star, tree and cellular mesh network structure, and the networking method is very flexible;

2. It can truly realize the compatibility of multi-type data. The gateway has a built-in OPCUA server, which can encapsulate different types of data collected from different nodes into a unified OPCUA information model, and send it to the upper computer for storage through Ethernet in real time, and the OPCUA client will analyze the model and analyze the data to achieve fast The process of data collection-transmission-encapsulation-transmission-storage-analysis;

3. A group of KB-level data can be collected at a frequency that can be set. The data is immediately transmitted to the host computer for storage through Ethernet, so subsequent data can overwrite the previous data at any time. This mechanism only needs to be stored in the gateway. Create a space for storing data as a cache, without worrying about insufficient data storage space.

4. The present invention can realize the function of communicating with various field bus devices, including Profibus devices, Modbus bus devices, Can bus devices, and HART bus devices.

5. The present invention can be applied to most of the data communication environments, and adopts the heterogeneous bus mode to carry out hierarchical identification on the field devices through the OPCUA address space, establish a hierarchical relationship model between the devices, and use the data model to carry out data processing Analytical processing.

6. The present invention can also connect multiple host devices through Ethernet, provide OPCUA service to the host, and at the same time, perform periodic data collection work through the Modbus bus.

7. The present invention establishes a relational model for field devices through embedded OPCUA technology, and provides a unified interface data model externally.

Description of drawings

Fig. 1 is a block diagram of an embodiment of the present invention;

Fig. 2 is the composition block diagram of communication interface conversion module;

Figure 3 is a block diagram of the power supply unit;

Fig. 4 is the working principle diagram of the embodiment of the present invention;

Fig. 5 is a schematic diagram of software provided by the present invention;

Fig. 6 is a schematic diagram of the application provided by the present invention.

detailed description

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, the example of the present invention consists of a WIA-PA wireless transceiver unit, a WIA-PA network manager unit, an Ethernet interface unit, an Ethernet control unit, an externally expanded SRAM storage unit, a main control unit, and a serial port to a network server Unit, control button, indicator light unit, and power supply unit are composed of ten units. These ten units are divided into two parts: data acquisition unit and data processing unit according to their functions. These two parts are connected by Ethernet interface and network cable. The acquisition unit includes a WIA-PA wireless transceiver unit and a WIA-PA network manager unit, which are powered by the Ethernet interface; the main control unit and the Ethernet control unit in the data processing unit, the externally expanded SRAM storage unit, the serial port to the network server unit, The control button and indicator light units are connected in a star shape; the power supply unit supplies power to all other units in the data processing unit.

Wherein, the structural block diagram of the serial port-to-network server unit is shown in FIG. 2 . The serial port-to-network server unit includes pins, a TCP/IP serial port protocol conversion module and its peripheral circuit, and an Ethernet interface; the serial port-to-network server unit is connected to the main control unit and the power supply unit through pins, and the TCP The /IP serial port protocol conversion module can realize the conversion of single-chip serial port data and Ethernet data, and realize transparent data transmission between the WIA-PA network manager unit and the single-chip computer;

Described main control unit is made up of STM32F407 series microcontroller and its peripheral circuit that ST company produces;

The externally expanded SRAM memory unit is made up of an IS61WV102416BLL chip produced by ISSI and its peripheral circuits;

Described Ethernet control unit is made up of DP83848CVV chip and peripheral circuit thereof produced by TI company;

The indicator light unit is composed of patch LEDs;

The power supply unit is composed of a power connector, a primary step-down unit and a secondary voltage stabilization unit. As shown in Figure 3, the primary step-down unit is composed of a step-down switching power supply module produced by Jinshengyang Company and its peripheral protection and filter circuits. , 220V AC is connected through the power connector, and after passing through the anti-surge protection circuit, it is used as the input of the step-down switching power supply module. The anti-surge protection circuit makes the gateway have the performance of anti-lightning and impact; the step-down switching power supply module outputs 5V DC voltage , after the protection and filtering circuit, it is used as the input of the secondary voltage stabilizing unit; the secondary voltage stabilizing unit is composed of AS1117 linear voltage regulator and its peripheral filter and indicator circuit. The linear voltage regulator reduces the 5V DC voltage to the above units The required operating voltage is 3.3V, and the output of the linear voltage regulator is supplied to each unit after passing through a layer of filter circuit. An indicator light circuit is also connected at the end of the secondary voltage stabilizing unit to indicate whether the power supply unit is working normally.

Fig. 4 shows the working principle flow chart of the embodiment of the present invention, as shown in Fig. 4, the hardware device of the OPCUA data service gateway is arranged at the industrial site, and it is connected to 220V alternating current. The transceiver unit accesses the nodes arranged on the industrial site, and forwards the collected data to the WIA-PA network manager unit in real time; the WIA-PA network manager unit has a real-time operating system to collect data and temporarily store it, and then transmit it through the serial port. The network server unit transmits the data to the main control unit, and the main control unit transfers the data to the externally expanded SRAM for storage; in addition, the externally expanded SRAM storage unit is also used to store OPCUASDK; since the collected data may be in different formats and types, the main control unit The control unit encapsulates the received data in different formats into a unified OPCUA service through OPCUASDK, that is, the information model of OPCUA, and then transmits it to the host computer through the Ethernet control unit and Ethernet interface for storage, and the OPCUA client on the host computer The information model can be accessed, browsed and operated through the general service set, and the user can then analyze the data, monitor the operation of the industrial field equipment in real time, discover the possible problems of the industrial field equipment, and finally solve the problem.

The invention uniformly maps field-based equipment information to the constructed unified address space and service concentration, and provides users with a unified access interface through the WebService service.

The invention establishes a relational model for field devices through embedded OPCUA technology, and provides a unified interface data model to the outside, including device objects, attribute sets and attributes. The device object is the mapping of the physical device in the program; the attribute set includes common attribute set, dynamic attribute set and static attribute set. The general attribute set includes device type, device manufacturer, device function, etc. The static attribute set includes device rated voltage, rated current, rated power, etc. The dynamic attribute set includes device status, device current voltage, current, power, device running time, etc.

With reference to Fig. 5, the software specific embodiment of the present invention adopts following specific scheme: a kind of service adapter based on embedded OPCUA technology, it comprises: 1, OPCUASDK, 2, FreeRTOS embedded real-time operating system, 3, STM32F407 peripheral hardware drive, 4. Ethernet hardware driver module, 5. OPCUA server. Described OPCUASDK provides for OPCUA server: the library function used for development, the basic configuration of TCP network connection, the basic configuration of address space; The described FreeRTOS embedded real-time operating system can support the CortexM4 framework of STM32F407 chip; Described STM32F407 The peripheral driver includes timer driver, Modbus driver, GPIO driver, and FSMC driver, which provide the required peripheral driver functions for the OPCUA server; the Ethernet hardware driver module provides the required peripheral driver for Ethernet communication The function realizes the network communication function of the OPCUA server, so that the OPCUA client can access the OPCUA server through TCP; the OPCUA server provides a standard OPCUA access interface and a device data model for the OPCUA client.

Referring to Figure 6, the present invention can be directly embedded in different types of devices, and communicate directly with the OPCUA client in the host computer through Ethernet, and the client can display the relationship between field devices and the status of each device for the user. data model.

Claims (10)

1. an OPCUA data, services gateway apparatus, it is characterised in that including:

Serial ports turns webserver unit, and one end is connected with main control unit, and the other end is used for field equipment connecting, for realizing the bi-directional conversion of main control unit serial data and Ethernet data, and then realizes the data transmission between field apparatus and main control unit；

Ethernet interface unit, is connected with Ethernet control unit and host computer, for setting up the communication connection between main control unit and host computer, transmits for data therebetween and provides passage；

Ethernet control unit, is connected with Ethernet interface unit and main control unit, is controlled by main control unit, is used for the data transmission controlling between work and main control unit and the host computer of Ethernet interface；

Extend out SRAM memory cell, be connected with main control unit, be used for storing OPCUASDK, and the data for collecting provide memory space；

Main control unit, it is integrated in the communication module of field apparatus, turn webserver unit, Ethernet control unit for controlling serial ports, extend out SRAM memory cell, control the work of button and display lamp, its internal SRAM and FLASH, as level cache and flash memory, supports for providing for the operation of program；

Control button, is connected with main control unit, be used for waking gateway up in the standby state or reset gateway when internal processes encounters problems；

Indicator unit, is connected with main control unit, for indicating the duty of gateway；

Power supply unit, for converting the 3.3V direct-current working volts needed for all above unit to by 220V alternating voltage.

2. a kind of OPCUA data, services gateway apparatus according to claim 1, it is characterised in that described serial ports turns webserver unit and includes TCP/IP serial port protocol modular converter and peripheral circuit thereof and Ethernet interface.

3. a kind of OPCUA data, services gateway apparatus according to claim 1, it is characterised in that described Ethernet control unit is made up of ethernet PHY controller chip and peripheral circuit thereof.

4. a kind of OPCUA data, services gateway apparatus according to claim 1, it is characterised in that described main control unit is made up of MCU chip and the peripheral circuit thereof of STM32F407 series.

5. a kind of OPCUA data, services gateway apparatus according to claim 1; it is characterized in that; said supply unit includes power connection, step-down switching power module, filter circuit, circuit protection, linear voltage regulator, and described power connection is positioned at the edge of circuit board.

6. an OPCUA data, services gateway apparatus realize method, it is characterised in that comprise the following steps:

The node name of the field apparatus of its connection is set by main control unit, and describes static attribute and the address ID of each field apparatus；

When host computer OPCUA client initiates monitoring service, main control unit obtains the dynamic attribute of field apparatus by serial ports/Ethernet；

The dynamic attribute got is exported the node corresponding to OPCUA server by serial ports/Ethernet；

Reading service within OPCUA client call OPCUASDK, gets the attribute of respective nodes in OPCUA server.

7. an OPCUA data, services gateway apparatus realize method, it is characterised in that comprise the following steps:

The node name of the field apparatus of its connection is set by main control unit, and describes static attribute and the address ID of each field apparatus；

The dynamic attribute got is exported in the buffer memory to OPCUA server by main control unit by serial ports/Ethernet, waits that OPCUA client initiates service；

When host computer OPCUA client initiates monitoring service, data in buffer memory are assigned to the attribute of the corresponding node of OPCUA server by main control unit；

Reading service within OPCUA client call OPCUASDK, gets the attribute of respective nodes in OPCUA server.

8. the OPCUA data, services gateway apparatus according to claim 6 or 7 realize method, it is characterised in that also include:

When the property value of field apparatus is more than the threshold value of OPCUA server settings, stops the reading service within OPCUASDK, this property value is transferred in OPCUA client by the alarm mechanism within OPCUASDK.

9. the OPCUA data, services gateway apparatus according to claim 6 or 7 realize method, it is characterised in that the dynamic data that described OPCUA client gets is inserted in the data base being pre-configured with, and the historical information for field equipment data is inquired about.

10. the OPCUA data, services gateway apparatus according to claim 6 or 7 realize method, it is characterized in that, also include: described OPCUASDK produces the unique serial number of OPCUA server, and is supplied to OPCUA client, for identifying the uniqueness of OPCUA server.