AT14531U1 - Device and method for controlling a fieldbus system - Google Patents

Abstract

The invention relates to a device for controlling a fieldbus system (2), in particular a heating system having a plurality of components, wherein a first interface (3) for communication with the fieldbus system (2) and a second interface (4) for communication with a server (5) is provided, wherein the device (1) for bidirectional, encrypted communication between the server (5) and the field bus system (2) is executed. The invention further relates to a method for controlling such a device.

Description

description

DEVICE AND METHOD FOR CONTROLLING A FIELDBUS SYSTEM

The invention relates to a device and a method for controlling a fieldbus system, in particular a heating system with several components connected thereto.

In particular, in the field of heating technology, it is common to connect multiple devices via a fieldbus system, such as a CAN bus or a Modbus, to a large system. The devices are, for example, log wood boilers, thermal solar systems, buffer storage and one or more heating circuits that are supplied with it. To control the entire system usually local control devices are used in the art, which are only on site, and not remotely, in particular not via the Internet, controllable. One of the reasons for this is that each component of the system typically uses proprietary protocols and commands.

The object of the invention is to overcome this drawback and to provide a device which makes it possible to control a fieldbus system with multiple components from a distance, especially via the Internet. In this case, it should allow the device in particular to be able to control a wide variety of components with proprietary and independent protocols, without the end user having to know the protocols required for each.

These and other objects are achieved by a device for controlling the fieldbus system, in which a first interface for communication with the fieldbus system and a second interface for communication with a server is provided, wherein the device for bidirectional, encrypted communication between the Server and the fieldbus system is executed.

The device can be embodied, in particular, as a protocol converter or gateway, which is set up to receive encrypted messages from the server via an interface, to decrypt them, to convert messages readable for the components of the fieldbus system and to the fieldbus system via a further interface in the reverse direction, receive messages from the components of the fieldbus system via an interface, convert them into server-readable messages, encrypt them, and send them to the server via another interface.

This makes it possible for the user who only communicates with the server, the proprietary protocols of the components connected to the fieldbus need not be known. The protocol converter receives the data packets sent by the components of the fieldbus system and translates them into a separate protocol that is used to communicate with the server. This makes it possible to make all the data of the connected components uniformly accessible to the user via the server and the Internet. A direct communication between the server or the user and the individual components of the fieldbus system is neither provided nor required and according to the invention not even possible.

The device allows the customer to view, for example, the degree of charge (the temperature) of a buffer connected to the fieldbus to change the desired living room temperature of a heating circuit or to release the automatic ignition of the boiler and thus start the boiler. Unlike prior art controllers, the user does not have to adjust anything on the components of the system itself.

Also, the security of the system is increased, since the device prevents that can be accessed directly via the Internet to the field bus system itself. According to the invention it can be provided that the fieldbus system comprises further components, such as a boiler control, a solar controller, a buffer memory sensor, a temperature sensor and / or other components. According to the invention, it can further be provided that the first interface of the protocol converter is designed as a fieldbus interface, in particular a CAN or ModBus interface, the second interface is designed as a network interface, in particular an Ethernet interface and preferably further interfaces, in particular a USB interface, are provided.

The invention further extends to a server for controlling a device according to the invention, comprising a protocol server for encrypted communication with the protocol converter, a database interface for communication with a database server and / or a database, and a control server for receiving Commands for the fieldbus system. The dedicated control server makes it possible to receive proprietary messages from the components of the fieldbus. By querying the database, these messages can be converted into a uniform format and forwarded to the user.

The invention further extends to a system comprising a protocol converter according to the invention and a server according to the invention.

The invention further extends to a method for controlling a fieldbus system, in particular a heating system with a plurality of components, by an external server via a protocol converter connected to the fieldbus system, wherein the method comprises the following steps: In a first step, the authentication takes place and the establishment of an encrypted connection between the server and the protocol converter.

In a second step, the identification of the components connected to the fieldbus system and storage of this information in a database, for example by assigning a unique identifier.

In a third step, the query of the current measured values, parameters and cycles of the fieldbus system and storage in the database. If necessary, a change of one or more parameters of the fieldbus system takes place. Finally, the measured values, parameters and cycles of the fieldbus system in the database are updated at periodic intervals.

Measured values are values measured by the components of the fieldbus system (e.g., buffer temperature, outside temperature, oxygen content). Parameters designate all the settings on the components of the fieldbus system that can be changed by the user or set based on specific measurements or other parameters (e.g., wood-fired mode, various setpoint temperatures). Cycles are time programs such as the heating times or the ignition times. By defining the cycles, it can be defined, for example, which heating circuit should regulate when and at what temperature.

According to the invention it is further provided that the measured values, parameters and cycles are interrogated periodically in preferably different intervals, wherein the intervals are preferably taken from the type of connected components of the database.

According to the invention it is further provided that desired queries are collected by the server and transmitted at periodic intervals via the protocol converter to the fieldbus system. This has the particular advantage that certain measured values with high latency (for example the buffer temperature) are not queried in too short intervals, so that meaningful values are obtained in any case.

According to the invention, it is further provided that the encrypted communication of the server with the fieldbus system via the protocol converter comprises the following steps: First, the receipt of commands at a control server of the server takes place. Thereafter, the query of the database to determine the corresponding, the identified components of the fieldbus system associated control instructions, for example, under

Turn a unique identifier.

After that, the encryption of the now component-specific control instructions by a protocol server. Finally, the encrypted control instructions are forwarded to the protocol converter, possibly via the Internet. Furthermore, a receipt of the control instructions at the protocol converter, a decryption and forwarding of the component-specific instructions to the fieldbus system, if necessary in turn using a unique identifier of the addressed component.

The encrypted communication of the server with the fieldbus system via the protocol converter can according to the invention comprise the following steps: First, the receipt and encryption of data of the components of the fieldbus system takes place at the protocol converter. Thereafter, the encrypted data is forwarded to the server, possibly via the Internet. After that, the data is decrypted by a protocol server on the server. Thereafter, the query of the database to determine the meaning of the decrypted data. Finally, the decrypted data is stored in the database. If appropriate, then a query of the database by any, connected to the server or the Internet terminal.

According to the invention may further be provided that the protocol converter is not designed as a dedicated device, but is integrated into one of the components connected to the fieldbus.

The invention further extends to a computer program for carrying out the method according to the invention.

Further embodiments of the invention will become apparent from the description, the claims and the drawings. In the following the invention will be explained in more detail with reference to non-limiting embodiments.

Fig. 1 shows a schematic representation of a Proto kollumsetzers invention, which is connected to a field bus system; 2a-2e show sequence diagrams of various applications of an exemplary embodiment of the method according to the invention; FIGS. 3a-3e show exemplary embodiments of the transmission packets used by the protocol converter.

Fig. 1 shows a schematic representation of a protocol converter 1 according to the invention, which is connected to a fieldbus system 2, which is designed in the specific embodiment as a CAN bus or Modbus. In other embodiments, not shown, other fieldbus systems may be provided.

On the field bus system 2 are a boiler control 6, which is connected to a buffer memory sensor 8, a sensor 17 and an actuator 18, a temperature sensor 10 and a solar control 7 with a buffer memory sensor 8 and another sensor 17. All components are over the fieldbus system controllable, but each component uses a proprietary protocol.

The protocol converter 1 comprises a first interface 3, which is designed as a CAN or Modbus interface, and is connected via this with the fieldbus system 2. The communication via this interface 3 takes place in each case using the control commands required by the components.

Furthermore, the protocol converter 1 has a USB interface 9, which can be used for example for importing updates or for other maintenance tasks. In non-illustrated embodiments of the protocol converter is performed without a USB interface, as this is not mandatory for the function.

In addition, the protocol converter 1 via a second interface 4, which is designed as an Ethernet or WLAN interface, connected to the Internet. Protocol converter 1 and fieldbus system 2 are usually located in the same place.

In another location is a server 5, which includes several dedicated components: a protocol server 11, a database interface 12 and a control server 13. The protocol server 11 is used for communication with the Internet and the associated protocol converter 1. The communication with the protocol converter 1 is encrypted. The database interface 12 is used for communication with its own database server 14, which accesses a database 15. Finally, the control server 13 serves to receive commands for the components of the fieldbus system 2 from the Internet.

The control server 13 provides for the forwarding of messages of the components of the fieldbus system 2 to the Internet. Respective terminals 16 are also connected to the Internet.

Fig. 2a shows a sequence diagram of the process of authentication of the protocol converter 1 on the server 5. Once the Prokollumsetzer 1 is connected to the network, the protocol converter tries to connect to the server.

Other fieldbus participants are not involved. The server 5 determines whether or not a protocol converter is allowed to connect. This is decided on the basis of various criteria (such as the protocol version used). If the protocol version of the protocol converter is deprecated and does not support the encryption algorithm currently in use, the server can deny logon of this protocol converter - or it will approve the connection despite the outdated protocol version, and then communicate with this protocol converter using this protocol version. Which protocol versions are supported can be set in a configuration file.

2b shows a sequence diagram of the sequence of polling the identity of the boiler controller 6 and the solar control 7 on the fieldbus system 2. The server 5 sends an "Identify Request" to the protocol converter 1. This is then placed on the field bus 2, whereupon all components by sending back an " Identify Response " identify. This information is sent back to the server 5 by the protocol converter 1. The server then enters the information in the database 15. The server 5 executes an "Identify Request" every time a protocol converter 1 is logged on in order to find out which components are on the fieldbus system 2, so that the server can later inquire corresponding measured values and parameters.

Fig. 2c shows a sequence diagram of the interrogation of measured values, parameters and cycles. As soon as the server has received an "Indentify Request", it queries all measured values, parameters and cycles of this component.

This ensures that with every new connection all measured values, parameters and cycles with the current values are stored in the database. The server 5 can interrogate any measured value (e.g., living room temperature, boiler status, ...), parameters (e.g., room temperature setpoint, mode, ...), as well as cycle (e.g., heating times, firing times, ...). This is done by sending out a " Measured Request " Message sent by the server 5 to the protocol converter 1. The protocol converter 1 forwards the request to the respective component of the fieldbus system 2, which then uses a " measured value response " responds. Which measured values / parameters / cycles of which component should be queried and how many times can be set on the server in a database. Here, both global settings and specific settings can be made (for example, there may be a problem with a particular installation and therefore the boiler temperature must be queried more often). For example, every 17 seconds it is queried whether the hot water tank is currently active, but its temperature is only polled every 61 seconds (since this measured value is much sluggish).

Fig. 2d shows a sequence diagram of the collected query of measured values. Simultaneously with the initialization, the timers for the measured values, parameters and cycles start to run as soon as the server has received an "Identify Response". This means that a wide variety of measured values, parameters and cycles are polled periodically at different intervals. The server can change any parameter (e.g., oil burner ON, room temperature setpoint, ...) and each cycle (e.g., heating times, ...). For this purpose, it sends a "set parameter request" to the protocol converter 2, which is translated to the specific protocol and placed on the bus and interpreted and executed by the corresponding component.

Which measured values, parameters and cycles are queried and in which periods are queried can be adjusted by means of the controller type in a database. In particular, it may be the boiler temperature, the hot water temperature, the exhaust gas temperature, or a fault message.

These requests are sent from the server to the protocol converter, so it is sent a packet which may include one or more "measured value request" (or "Parameter Request", ...). Thus, e.g. summarized every 17 seconds timer.

Fig. 2e shows a sequence diagram of the process of changing a parameter. If the user wants to change a parameter, a command is stored in the database (e.g., Bus No. 1 should change parameter number 0x9102 (Housing temperature setpoint) to 22 ° C). Thereafter, the control server 13 is informed that a new command exists ("SET PARAM"). This now causes the database interface 12 to take the command from the database and to send via the protocol server 11 to the protocol converter 1. Once this has been done, the command is deleted from the database again.

In a preferred embodiment, the protocol used by the protocol converter 1 comprises two components: a crypto protocol, which is used for encryption and authentication, and a data protocol, which is used for data exchange. Each data packet (19) is embedded in a specific crypto packet (20). In addition, the protocol version is transmitted with every package sent.

Fig. 3a shows a typical transmission packet used for communication of the server 5 with the protocol converter 1. It comprises a crypto header and a cryp-to-tail as crypto packet 19, which include the actual data packet (20). The transmission packet shown instructs the protocol converter to set the parameter with the number 0x9102 (housing temperature setpoint) of the controller with the bus number 0x01 to the value 22.

3b shows in its upper part an example of an Identify Request packet which is sent to the protocol converter. The Identify Request is used to identify all controllers on the bus. The protocol converter translates the identification request for the components on the bus and, as shown in the lower part of FIG. 3b, forwards it to the fieldbus system 2 in a different, proprietary form.

After that, all components report with an Identify Response in their respective proprietary protocol. As soon as an Identify Response is received on the bus, it is received by the protocol converter, translated and encrypted forwarded to the server.

Fig. 3c shows an example of an "Identify Response" translated by the protocol translator. The Identify Response comes from the protocol converter in response to an Identify Request. The Identify Response shown reports a controller with the BusNr 1 of the controller type OxOBOO (LambdaControl 2 Plant) with the serial number 01234567 and the software version 17.17 (HEX 0x10. 0x10). As the server sends out an Identify Request for each component, it is possible to save in the database which components are present. Thereafter, the initialization or the periodic query is started.

Fig. 3d shows an example of a measured value request. With the aid of a measured value request, the server can query measured values of individual controllers on the bus. This packet causes the protocol converter 1 to send three measured value requests on the bus. And always for the

BusNr 1: 0x0001 Boiler status, 0x0003 Actual temperature boiler, 0x0607 Lambda.

Fig. 3e shows an example of a measured value response. For each measured value Response, the protocol converter sends its own measured value Response to the server. The presented packet responds to the server that Knife 0x0001 (Boiler status) of the controller with BusNr 1 has the value 1 (Boiler ON). As described above, e.g. three measured values requested by the server, the server also gets 3 measured value responses from the protocol converter. These are not summarized like the measured value requests from the server.

The invention is not limited to the illustrated embodiments, but includes all devices and methods within the scope of the following claims.

REFERENCE SYMBOLS 1 Protocol converter 2 Fieldbus system 3 First interface 4 Second interface 5 Server 6 Boiler controller 7 Solar controller 8 Buffer sensor 9 USB interface 10 Temperature sensor 11 Log server 12 Database interface 13 Constroll server 14 Database server 15 Database 16 Terminal 17 Sensor 18 Actuator 19 Data packet 20 Crypto packet

Claims (14)

Device for controlling a fieldbus system (2), in particular a heating system with several components, characterized in that a first interface (3) for communication with the fieldbus system (2) and a second interface (4) for communication with a server ( 5) is provided, wherein the device (1) for bidirectional, encrypted communication between the server (5) and the fieldbus system (2) is executed. 2. Apparatus according to claim 1, characterized in that the device (1) is designed as a protocol converter (1) or gateway, which is adapted to a. to receive encrypted messages from the server (5) via the interface (4), to decrypt them, to convert messages readable for the components of the fieldbus system (2) and to send them via the interface (3) to the fieldbus system (2), and b. Receive messages of the components of the fieldbus system (2) via the interface (3) to implement in messages readable for the server (5), encrypt and send via the interface (4) to the server (5). 3. Apparatus according to claim 1 or 2, characterized in that the field bus system (2) further components, such as a boiler control (6), a solar controller (7), a buffer memory sensor (8) and / or a temperature sensor (10). 4. Device according to one of claims 1 to 3, characterized in that the first interface (3) is designed as a fieldbus interface, in particular CAN or ModBus interface, the second interface (4) as a network interface, in particular Ethernet interface is executed and preferably further interfaces, in particular a USB interface (9) are provided. 5. Device according to one of claims 1 to 4, characterized in that the device in one of the field bus connected components (6, 7, 8, 10) is integrated. 6. server (5) for controlling a device according to one of claims 1 to 5, comprising a. a protocol server (11) for encrypted communication with the protocol converter (1), b. a database interface (12) for communicating with a database server (14) and / or a database (15), and c. a control server (13) for receiving commands for the fieldbus system (2). 7. System of a device according to one of claims 1 to 5 and a server according to claim 6. 8. A method for controlling a fieldbus system (2), in particular a heating system with a plurality of components, by an external server (5) via a protocol converter (1) connected to the fieldbus system (2), characterized in that the method comprises the following steps: a. Authenticating and establishing an encrypted connection between the server (5) and the protocol converter (1); b. Identification of the components connected to the fieldbus system (2) and storage in a database (15); c. Query of the current measured values, parameters and cycles of the fieldbus system (2) and storage in the database (15); d. if necessary, changing one or more parameters of the fieldbus system (2); e. Periodic updating of the measured values, parameters and cycles of the fieldbus system (2) in the database (15). 9. The method according to claim 8, characterized in that the measured values, parameters and cycles are polled periodically preferably in each case different intervals, which are preferably taken on the basis of the type of connected components of the database (15). 10. The method according to claim 8 or 9, characterized in that desired queries collected by the server (5) and transmitted at periodic intervals via the protocol converter (1) to the fieldbus system (2). 11. The method according to any one of claims 8 to 10, characterized in that the encrypted communication of the server (5) with the fieldbus system (2) via the protocol converter (1) comprises the following steps: a. Receiving commands at a control server (13) of the server (5); b. Querying the database (15) for determining the corresponding control instructions associated with the identified components of the fieldbus system (2); c. Encryption of the control instructions by a protocol server (11); d. Forwarding the encrypted control instructions to the protocol converter (1), optionally via the Internet; e. Receipt of the control statements at the protocol converter (1), decryption and forwarding to the fieldbus system (2). 12. The method according to any one of claims 8 to 10, characterized in that the encrypted communication of the server (5) with the fieldbus system (2) via the protocol converter (1) comprises the following steps: a. Receiving and encrypting data of the components of the fieldbus system (2) at the protocol converter (1); b. Forwarding the encrypted data to the server (5), optionally via the Internet; c. Decryption of the data by a protocol server (11) on the server (5); d. Query the database (15) to determine the meaning of the data; e. Storage of the decrypted data in the database (15). 13. The method according to any one of claims 8 to 12, characterized in that the protocol converter (1) for communication with the server (5) uses a generic protocol, wherein data packets (19) are embedded in crypto packets (20). 14. The method according to any one of claims 8 to 13, characterized in that the protocol converter (1) in one of the fieldbus connected components (6, 7, 8, 10) is integrated. For this 6 sheets of drawings